Turbogenerator Fundamentals

November 6th 2006

Brush Electrical Machines Ltd. PO Box 18, Loughborough, Leicestershire, LEI1 lHJ, England Telephone: +44 (1509) 61 1511 Telefax: +44 (1509) 610440

E-Mail: sales@bem.fkiet.com Web Site: http:llwww.fki-et.com/bem

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TRAINING MANUAL CONTENTS

........................................................................................................................................ 1 INTRODUCTION 3 ............................................................................................................... 2 GUIDE TO TRAINING MANUAL 3

................................................................................................................. 3 PROJECT DOCUMENTATION 3 ............................................................................................................................... 4 TRAINING MODULES 4

ITraining Manual CJ Brush Electrical Machines Lld . 2006

I INTRODUCTION

This Training Manual is intended to provide Operators with an understanding of the concepts and procedures used in the design and manufacture of generators and ancillary equipment.

In addition to general background information, the Training Manual incorporates details of basic design concepts and project specific information as appropriate. A schedule of the training modules provided, and a summary of their content is given in Section 4.

2 GUIDE TO TRAINING MANUAL

Electronic copies of the Training Manual are provided in Adobe Acrobat format (PDF files), which includes bookmarks or links to enable the user to navigate between the various Sections within the manual. To move to the required Section, 'click' on the bookmark in the left hand portion of the screen.

3 PROJECT DOCUMENTATION

The Training Manual is designed to supplement the information given in other project documentation

9 Operating & Maintenance Manual comprising Installation 8 Commissioning procedures, Operation & Maintenance procedures, Drawings. Control & Monitoring Equipment and Suppliers Data.

9 Instruction ManualslHandbooks for Brush ancillary equipment 9 Quality Dossier incorporating as shipped equipment settings and, where B ~ s h has an involvement,

as commissioned settings.

ITraining Manual Q Brush E lecth l Machines Ltd. 2006

4 MODULES

GENERAL Introduction To Brush Electrical Machines Ltd.

Warning Symbols; Health & Safety At Work Act (1974); Control Of Substances Hazardous To Health (COSHH Regulations 1999); Operation & Maintenance; Protection & Monitoring Maintenance Philosophies Maintenance; Machine Deterioration; Maintenance Philosophies; Sensory Perception Principles Of AC Generation Faraday's Law Of Electromagnetic Induction; Three Phase Generation; Generator Excitation Control Systems

GENERATORS DAX Generators Introduction; Stator; Rotor; Ventilation System; Bearings Open Ventilation Systems Internal Air Circuit; External Air Circuit Closed Air Water Cooling Systems Introduction; Maintenance; Pipework Systems Bearings -Fixed Profile Fixed Profile Bearings; Bearing Lubrication; Pressure Oil Seal Jacking Oil Panel Requirement For Jacking Oil; Jacking Oil Panel; Pipework Systems Generator EnclosurelCanopy

Generator Line And Neutral Cublcles Line Cubicles; Neutral Cubicles; Combined Line & Neutral Cubicles Generator Line Cublcles Generator Neutral Cubicles Generator Cleaning Cleaning A Seriously Contaminated Machine; Cleaning By Hand; COz Shot Blasting; Jet Water-Wash; Post Insulators Generator Rotor Removal Introduction; Precautions; Site Requirements; Rotor Removal Kit Components; Rotor Removal Procedure; Rotor Removal Illustrations; Rotor Threading Procedure; Rotor Transportation; Rotor Balancing GENERATOR INSTRUMENTATION Resistance Temperature Detectors And Thermocouples General; Recommended Alarm & Trip Settings; Resistance Temperature Detectors; Ovewoltage Protection; RTD Calibration Bently Nevada Vibration Monitoring Vibration Monitoring; Velocity & Acceleration Transducers; Measurements On Rotating Machinery

04 GENERATOR SYSTEMS 04.01 . O l Power Generation Systems

Prime MoverlGenerator; Generator . Operation; Automatic Voltage Control; Parallel Operation; Governor Droop; Generator Output

04.02.01 Generator Synchronislng Introduction; DC Generators; AC Generators; Synchronising AC Generators; Lamp Synchronising; Synchroscope; Synchronising At The Switchboard/Control Panel; Automatic Synchronising; Check Synchronising; Closing Onto Dead Busbar

04.03.01 Capability Diagrams Introduction; Stator Current; Power Output; Rotor Current; Stability Of The Rotor; Temporary Limitation; Use Of Capability Diagram; Capability Diagram For Synchronous Motor; Capability Diagram For Synchronous Condenser

(Training Manual O Brush Electrical Machines Ltd. 2006

Connection Of Generating Plant Introduction; G59 Recommendations Electrical Device Numbers 8 Functions Introduction; Device Numbers Equipment 8 Switchgear Labelling (853939) Introduction; General; Prefix Letter; Wire Numbers; Suffix Letters; Numbering Table High Voltage Phasing Checks Introduction; Phasing Out Of HV Systems; Phasing Sticks Electrical Power Resistance, Inductance & Capacitance; Current 8 Voltage; Active Power; Reactive Power; Power Factor & Apparent Power; Three Phase Power, Tariffs 8 Power Factor Correction. GENERATOR EXCITATION CONTROL EQUIPMENT Modular Automatic Voltage Regulator (MAVR) - Principles The Brushless Generator; Generator Operation; Principles Of Automatic Voltage Control; Parallel Operation; The Generator Capability Diagram

ITralnlng Manual 0 Brush EWrlcal Machines Ltd 2006

INTRODUCTION - 0 . ..

-BRUSH B E M Ltd.- rraining Module: 01.01.01 I Issue A I Date September 2002 Page. I of 12

INTRODUCTION TO BRUSH ELECTRICAL MACHINES LTD.

l l . O l . O l (A) Introduction To BEM.doc Q Brush Electrical Machines Ltd. 2002

-1 I INTRODUCTION C TO BRUSH ELECTRICAL MACHINES LTD . I . - .. -BRUSH B E M Ltd.- Training Module: 01.01.01 1 Issue: A 1 Date: September 2002 I Page: 2 of 12 CONTENTS 1 FKI PLC ...................................................................................................................................................... 3

1.1 Introduction ........ ... ........................................................................................................................... 3 ........................................................................................................ ......... 1.2 FKI Energy Technology .. 3

............................................................................. 1.3 Companies In The FKI Energy Technology Group 4 2 BRUSH ELECTRICAL MACHINES LTD . -HISTORY ......................................................................... 6

2.1 Charles Francis Bmsh ................... .... ............................................................................................. 6 2.2 Development ....................... .. ............................................................................................................ 6

.......................................................................................................................... 2.3 Other Brush Products 7 2.4 Generators ........................................................................................................................................ 7 2.5 Diversification ...................................................................................................................................... 8 2.6 Development ..................................................................................................................................... 8

................................................................................................................. 2.7 Brush Loughborough Site 9 3 BRUSH ELECTRICAL MACHINES LTD ................................................................................................. 10

3.1 introduction ............... ... .................................................................................................................. 10 3.2 Products ......................................................................................................................................... 10 3.3 Industries Served ....................... .. ................................................................................................ 11 3.4 Quality ............................................................................................................................................. 11

. . 3.5 Aiter-Sales Service B Tralnlng ........................................................................................................ 11

01.01.01 (A) Introduction To BEM.doc 0 B ~ s h Electrical Machines Ltd . 2002

[-imm/ INTRODUCTION C TO BRUSH ELECTRICAL MACHINES LTD. 1 - . - . . -BRUSH B E M Ltd.- Training Module: 01.01.01 I Issue: A I Date: September 2002 I Page: 3 of 12

1 FKI PLC

1.1 Introduction

FKI plc is a major international engineering group. FKI has world leading positions in its specialised business areas of automated logistic solutions, lifting products and sewices, hardware and energy technology products.

FKI was incorporated on 6 March 1920 in England under the companies Acts 1908 to 1917 and was re-registered on 3 June 1982 as a public limited company under the Companies Acts 1948 to 1980. The Group has operations in more than 30 countries and in the year ended 31 March 2002. its turnover amounted to f 1.6 billion. and employs just under 16.000 people. b

1.2 FKI Enerav Technoloqy

C WKI PIC I I I C I

.t)&~~ll+t.,, Lifting Products L Switchgear & Transformers Rotat~ng Machines Companies Traction &Control

Companies I Companies I I HAWXI . 110011c1 < ! - WRIC.. .OU"*l

-A.7... .SOD,.I, .Owl. f- r+$i - eri~tor bbcock Baur.

SOYTW WALLS

-8RU6H S E Y "a- * , 1 . 1 , .

* ~ ( l lndustrinl D r iw

@@a WFroude Consine n a f ~ \ b F r n Trihnologr WFroude liofmann

rn -%I. Yd" .UlcmmtD*L.m @ Mala(iMotori

FKI Electrical Engineering Group was established in 1996 following the acquisition of the Hawker Siddeley Electric Power Group and Marelli Motori. These acquisitions, added to the existing presence of Whipp & Bourne, Laurence Scott & Electromotors and Froude Consine within FKI, made up a Group of world class stature with synergies of technology, manufacturing, purchasing and sales. FKI Electri&l Engineering, along with the Measurement and Controls Division, formed FKI plc's Engineering Group. In July 2001, this became FKI Energy Technology.

01.01.01 (A) Introduction To BEM.doc O Bwsh Eklrical Machines Lld. 2002

p m i m # q INTRODUCTION TO BRUSH ELECTRICAL MACHlNES LTD.

-BRUSH B E M Ltd.-

@ - . - ...

Training Module: 01.01.01 I Issue: A 1 Date: September 2002 I Page: 4 of 12 FKI Energy Technology is a leading independent supplier of rotating machines, particularly turbogenerators, switchgear and transformers; measurement and control products and is a significant supplier of other electrical products. Products and systems are sold to manufacturers of turbines, pumps, compressors, fans and other machines and to a wide variety of Customers in industry, power generation, oil and gas supply, air separation, petrochemical and contracting.

Main businesses in the FKI Energy Technology group are:

Rotating Machines: High, medium and low voltage electric motors; turbo, medium and low voltage generators; industrial drives, control equipment, frequency changers, engine and vehicle test systems. Switchgear: Indoor switchgear, outdoor circuit breakers, ring main units, pole mounted reciosers and DC switchgear. Transformers: Power, system and distribution transformers, pole mounted transformers and on load tap changers. Traction: Rail locomotive manufacture and refurbishment. Measurement and Control : Measurement and control devices and systems. b

1.3 Comoanies In The FKI Enerav Technoloav Grouo

Many of the individual companies have histories going back over 100 years. These companies include:

Brush Electrical Machines Ltd.: Located at Loughborough in the UK and is designated as FKl's Centre of Excellence for the design and manufacture of power management systems and air cooled 2-pole turbogenerators up to 150MVA.

Brush HMA bv: The company, formerly known as 'HMA Power Systems' and before that 'Holec Machines and Apparaten', has been established for over 115 years and became part of FKI Energy Technology at the beginning of 2000. Brush HMA is FKl's Centre of Excellence for the design and manufacture of Cpole generators with ratings between 10MVA and 65MVA.

Brush SEM sro: Located at Plzen in the Czech Republic and designated as FKl's Centre of Excellence for the design and manufacture of air cooled 2-pole turbogenerators above 150MVA, hydrogen cooled generators and hydrogenlwater cooled generators up to 1100MVA and the refurbishment of hydro generators up to 355MVA.

Brush Transformers: Based in Loughborough, UK, Brush Transformers is a major international manufacturer of transformers. With over a century of experience, Brush Transformers manufacture a wide range of distribution, power, dry type, cast resin and traction transformers, along with flameproof transformers and switchgear.

FKI Industrial Drives: Formed by the merger of Heenan Drives and Brush Industrial Controls, and now provide state of the art variable speed drive products from a new centrally located facility in Loughborough. Products also include AC sensorless flux vector inverters, synchronous motor drives and DC thyristor drives covering a power range from 0.37kW to 20MW. Fully engineered drive systems designed to customer specifications are available..

Hawker Siddeley Power Transformers: Based in Walthamstow. London, Hawker Siddeley Power Transformers is a major international manufacturer of power transformers including generator transformers for steam, hydro, nuclear and gas turbine power stations.

Hawker Siddeley Switchgear: Based in Blackwood in South Wales, Hawker Siddeley Switchgear are an international producer of Switchgear. The Blackwood site is a centre of excellence for switchgear manufacture, producing a range of indoor and outdoor distribution switchgear.

01.01.01 (A) Introduction To BEM.doc O Brush Electrical Machines Ltd. 2002

Laurence Scott And Electromotors: Are the UK's premier manufacturer of electric motors (high and low voltage, ac and dc) and electro-mechanical power transmission product! (gearboxes, geared motors, eddy current variable speed drives, electro-pneumatic clutch/brakes). Brand names include LSE, NECO, EPG. TASC, NORAC. HEENAN. PSS GLENPHASE, EDC, SLENDAUR, CENTAUR.

Marelli Motori: Produce a range of low and medium voltage asynchronous motors, DC motors and synchronous generators in a large variety of designs and power ranges up tc 3,000 kW. The factory is situated in Vicenza in the north of Italy, and has more than one hundred years of experience in the production of rotating electrical machines.

South Wales Transformers: Based in Blackwood, South Wales, South Wales Transformer! is a major international manufacturer of distribution transformers and substations. Thr Blackwood site is a centre of excellence for distribution transformer manufacture, producing z wide range of liquid-filled distribution transformers, both pole- and ground-mounted, anc packaged substations.

Whipp 8 Bourne: Established in 1903, and based in Rochdale. Lancashire, Whipp anc Bourne has long been a leader in heavy duty electrical switchgear. Products include a range of DC Circuit Breakers, Switchgear and Auto Reclosers. b

1.01.01 (A) Introduction To BEM.doc Q Brush Electrical Machines Ltd. 2002

2 BRUSH ELECTRICAL MACHINES LTD. -HISTORY

2.1 Charles Francis Brush

TO BRUSH ELECTRICAL MACHINES LTD.

Figure 1: Charles Francis Brush

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C . . ..

The original company was the Anglo-American Brush Electric Light Corporation which was established in 1879 in Lambeth, London, to exploit the inventions of Charles Francis Brush (1849-1929). Brush, born in Cleveland, Ohio, had developed his first dynamo in 1876 and founded the American Brush Company in 1881. This American company lasted until about 1891. b

issue A I Date September 2002 I Page 6 of 12

Lighting equipment (both arc lamps and incandescent lights) was the main product at first, expanding with the formation of lighting supply companies throughout the country. After an early boom in the promotion of lighting companies, the Electric Lighting Act of 1882 laid down new and onerous conditions of operating so that a general period of stagnation followed in the newiy-born electrical industry.

However, there were some developments prior to the repeal of the Act in 1888, mainly in the field of industrial electrification. Thus the company was able to thrive on the manufacture of dynamos, motors, switchgear and small transformers. Trade again increased after 1888 and the works in Lambeth were no longer adequate for the vast increase in orders. New premises were required and, in the following year, the Falcon Engine and Car Works in Loughborough was purchased.

Figure 2: Brush Works (Early)

01.01.01 (A) lntmduction To BEM.dcc 0 B ~ s h Electrical Machines Ltd. 2002

The title of the company was changed soon after the movement to Loughborough. At first, only the heavier manufacturing was transferred from Lambeth, but by 1895 most of the production was concentrated in the Falcon Works which by now incorporated large extensions. t

2.3 Other Brush Products

- - -

Figure 3: Brush 'Products' Prior to the First World War, tramcars and electrical engineering were the mainstays 01 production. The works employed about 2,000 men around 1910. Wartime, production was mainly concerned with munitions although vehicle bodies and even aircraft were constructed t

2.4 Generators

Figure 4: 5000kW Brush-Ljungstrom Turbogenerator

I1 .O1 .O1 (A) Introduction To BEM.doc c3 Brush Electrical Machines Ltd. 2W:

Electrical equipment sales remained steady during the period after World War 1. Turbine production experienced a great boom after 1918 when some 20 complete turbines with the attendant equipment were delivered each year. The size of these machines was in the 1.500 kW, 3,000 kW and 5,000 kW ranges, and they were well suited to the small municipal and company electricity works then in vogue. b

2.5 Diversification

Employment in the works fell from a peak in 1925 when about 2,500 were employed to 1,500 some ten years later. The area of the works altered little. from 33 acres in 1924 to 35 acres in 1935 when the workshops covered about five acres.

The first heavy oil engine made its appearance in 1935 and three years later in an attempt to diversify the range of products and to cater for an increasingly important line of business, the firm of Petters Ltd was taken over. Petters had been established in Yeovil. Somerset since the mid-19th century and had developed their first internal combustion engine in 1895. All the production was transferred to Falcon Works and remained there until 1948~when the former Lagonda Works at Staines, Middlesex were bought.

After World War II the demand for heavy electrical equipment, dormant for many years. returned to the company making good the damage of wartime losses, and also encouraging renewal of large-scale capital investment in power generation. The new companies in the Brush Group were now more competitive in modern conditions and the two branches. ABOE (Associated British Oil Engines) and Brush, were complimentary in engine building and electrical equipment. Four-wheeled battery electric vehicles first appeared in 1947 and in the same year the Company returned to railway work after a lapse of many years, when diesel and diesel-electric locomotives were built in conjunction with W.G Bagnall Ltd of Stafford. Further companies joined the Group in 1950 when the National Gas & Oil Engine Company Ltd, Hopkinson Electric Company Ltd and the Vivian Diesels & Munitions Company Ltd of Canada were taken over. The title was changed to the "Brush - ABOE Group'of Companies".

This was a period of great expansion with a large export drive and increasing capital investment in the industry. The 40 million of orders in 1951 were more than twice those of 1950. b

2.6 Develooment

In April 1957 an offer of 22 million from the Hawker Siddeley Group was adopted and amalgamation took place. The Brush Group of companies was incorporated into the Hawker Siddeley Group under the name of Brush Electrical Engineering Co., Ltd. and had offices in Dukes Court, Duke Street, St James's, London S.W.1.

In November 1991, the Hawker Siddeley Group was taken over by BTR plc in a f 1.5 billion bid. In the subsequent re-organisation Brush Electrical Machines Ltd became a major company within the BTR Electric Power Group, and the company's Traction Division became a separate company. Brush Traction Ltd.

In November 1996, the FKI Group of Companies acquired the Hawker Siddeley Electric Power Group from BTR, Brush Electrical Machines and the other Brush companies joining the Group's Engineering Division. Following this, BrushTraction Ltd reverted to being a division of Brush Electrical Machines Ltd, and the Company's Industrial Controls Division became part of FKl's LSE Division.

Brush Electrical Machines Ltd. is now one of FKI Energy Technology's Rotating Machines companies and is designated as the Centre of Excellence for the design and manufacture manufacture of power management systems and air cooled 2-pole turbogenerators up to 150MVA. Bmsh BEM joined with sister companies Brush HMA and Brush SEM to found the Brush Turbogenerators organisation. b

.Ol .Ol (A) Introduction To BEM.doc @ Bmsh Electrical Machines Ltd. 2002

INTRODUCTION TO BRUSH ELECTRICAL MACHINES LTD.

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2.7 Brush Louahborouah Site

Figure 5: Brush Works, Loughborough In October 1960 the Falcon Works employed about 4,300 workers in the 40 acres ol workshops in a total site area of 59 acres. A majority of workers, 3.700, were employed or heavy electrical work whilst 500 were in the Traction Division and 100 on electric vehicle construction. The main production of the works still centred on electrical engineering witb heavy transformers, generators, motors, switchgear etc.

In 1970 Hawker Siddeley Power Engineering, a project engineering group, was formed as a separate company with an office at a nearby site in Burton-on-the-Wolds and another at Chelmsford in Essex. Twelve months or so later, in 1971, the product divisions of the Brush Electrical Engineering Company Ltd were formed into separate manufacturing companies, Initially these comprised Brush Electrical Machines Limited, Brush Switchgear Ltd and Brush Transformers Limited, with Brush Switchgear taking on the responsibility of the Fusegea~ Division until January 1973 when Brush Fusegear Ltd was formally constituted.

By this time there were approximately 5,000 workers on the Loughborough site. F

1.01.01 (A) Introduction To BEM.doc GI Brush Electrical Machines Ltd. 200;

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3 BRUSH ELECTRICAL MACHINES LTD.

3.1 Introduction

- BRUSH B E M Ltd. - Figure 6: Brush Electrical Machines Ltd. Logo

Brush Electrical Machines Ltd. is now one of FKI Energy Technology's Rotating Machines companies and is designated as the Centre of Excellence for the design and manufacture manufacture of power management systems and air cooled 2-pole turbogenerators up to I50MVA. Brush BEM joined with sister companies Brush HMA and Brush SEM to found the Brush Turbogenerators organisation.

Company turnover for the financial year 2001/2002 was approximately 90 million. Over 90% of production was exported.

The company employs approximately 770 people. of whom 500 are in production. b

3.2 Products

Our product portfolio, including relevant FKI Energy Technology products, includes:

9 CONTROLS PRlSMlC PMS power management systems for marine power and propulsion, offshore and onshore oil and gas applications, industrial and dockland installations. A range of automatic voltage regulators and excitation control equipment for generators and synchronous motors.

9 GENERATORS Air cooled 2-pole turbogenerators for gas and steam turbine drive up to 200MVA, 15kV. Hydrogen and combined cooled 2-pole turbogenerators up to 1 IOOMVA, 25kV. Air cooled 4-pole turbogenerators up to 65MVA, 15kV. Multi-pole synchronous types for diesel engine drive up to 30MVA, 15kV..

9 MOTORS Multi-pole synchronous single, multiple and variable speed types up to ZOMW, 15kV. 20-pole induction types up to 20MW, 15kV. LV cage induction types up to 1.5MW. DC types up to 120kW. Traction types up to 1000kW. Flameproof types.

9 SWITCHGEAR Withdrawablelfixed vacuum circuit breakers, rated up to ISkV, 3150A, 40kA. Withdrawable fused vacuum contactors, rated up to 7.2kV, 400A, 40kA.

9 TRANSFORMERS Distribution transformers 315kVA to 2500kVA. Power Transformers 2.5MA to 6OMVA up to 145kV. System transformers up to IEOMVA, 150kV.

9 VARIABLE SPEED DRIVES . - AC inverters up to 7MW, 1800V. AC synchroconverters up to 20MW. DC drive systems up to 3.5MW b

0 1 . O l . O l (A) Introduction To BEM.doc Q Brush Electrical Machines Ltd. 2002

6 R\U;SH INTRODUCTION f l 1 TO BRUSH ELECTRICAL MACHINES LTD. I - . - .. -BRUSH B E M Ltd.- Training Module: 01.01.01 I Issue: A I Date: September 2002 I Page: 1 1 of 12

3.3 Industries Served

Bmsh provides a complete electrical service to all sectors of the power industry. From a product portfolio encompassing generators, including control systems, for base load or intermittent duty, synchronous motors, power management systems and fully co-ordinated packages of electrical equipment. Brush can provide equipment and services to meet the most demanding specifications.

Bmsh is renowned for the kind of robust yet versatile designs of generators and motors weli suited to the harsh operating environments encountered at oil and gas installations both onshore and offshore. This has led to Brush gaining an excellent reputation as a world class supplier to this demanding market.

Brush also provides a complete electrical service to the marine industry. From generators and control systems, to complete electrical propulsion and auxiliary power system packages for naval, merchant and special purpose vessels.

In addition, Bmsh can select and configure systems built from components sourced from throughout FKI Energy Technology group and elsewhere, including generators, motors, control systems, variable speed drives, switchgear and transformers, etc. h

3.4 Qualitv

I S 0 9001 Cem?icate No FM 12096

Figure 7: QA Registration Since 1991, the Company has been registered to IS0 9001 standard, which governs the quality of design, manufacture and service. Maintaining this registration, has become a cornerstone of management policy. All equipment complies with relevant European. American and International standard specifications. h

3.5 After-Sales Service 8 Training

A comprehensive service is offered by the Service Department, located at Loughborough, dealing with the commissioning, service, repair and maintenance requirements on a world- wide basis. In addition, service centres in the USA, Malaysia. The Netherlands and Canada, along with local service partners in many other countries, can offer on-the-spot assistance. Comprehensive operator training courses for all products and systems are available either at the factory or at site. h

01.01.01 (A) Introduction To BEM.doc 0 Brush Electrical Machines Ltd. 2002

INTRODUCTION @ -BRUSH B E M Ltd.- TO BRUSH ELECTRICAL MACHINES LTD. 1 - . . ... Training Module: 01.01.01 I Issue: A I Date: September 2002 I Page. lZof l2

BLANK PAGE

SAFETY

SAFETY

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SAFETY -BRUSH B E M Ltd.- Training Module: 01.02.01 I Issue A I Date September 2002 Page 2 of 6

1 CONTENTS I .................................................................................................... .................... WARNING SYMBOLS .. 3

............................................................................................ HEALTH 8 SAFETY AT WORK ACT (1974) 3 CONTROL OF SUBSTANCES HAZARDOUS TO HEALTH (COSHH REGULATIONS 1999) ............... 4

....................................................................................................................................... 3.1 Introduction 4 .............................................. ................................... 3.2 COSHH Data For Standard Components .. 5

OPERATION 8 MAINTENANCE ............................................................................................................... 6 PROTECTION AND MONITORING DEVICES .......................................................................................... 6

I WARNING SYMBOLS

Warning symbols used in manuals are as follows:

8 Mandatory Notice - Instruction to be followed. A Danger, General - Caution to be exercised. Appropriate safety measures to be taken, A Danger. Electricity - Caution to be exercised. Appropriate safety measures to be taken

Danger. Harmful or Irritating Substance - Caution to be exercised. Appropriate safety measures to be taken. +

2 HEALTH (L SAFETY AT WORK ACT 119741

The information hereunder is supplied in accordance with Section 6 of the Health and Safety at Work Act 1974 with respect to the duties of manufacturers, designers and installers in providing health and safety information to Customers. The information advises of reasonably foreseeable risks involved with the safe installation, commissioning, operation, maintenance, dismantling, cleaning or repair of products supplied by Brush Electrical Machines Ltd.

I Every precaution should be taken to minimise risk. When acted upon, the following precautions should considerably minimise the possibility of hazardous incidents. I Delivery Checks: Check for damage sustained during transport. Damage to packing cases must be investigated in the presence of an Insurance Surveyor. Handling: Sling packing cases where indicated. Equipment not in a packing case, or removed from a packing case must only be lifled by the lifting points provided. Do not lifl complete machines by lugs on heat exchangers or air silencers etc.

Storage: Unless the equipment has been designed for outside use or specifically packed for outside storage, store inside in a dry building, in line with the manufacturer's recommendations.

Installation: Where installation is made by engineers other than Brush Electrical Machines Ltd. personnel, the equipment should be erected by suitably qualified personnel in accordance with relevant legislation, regulations and accepted rules of the industry. In particular, the recommendations contained in the regulations with regard to the earthing must be rigorously followed.

Electrical Installation:

A IMPROPER USE OF ELECTRICAL EQUIPMENT IS HAZARDOUS. It i s important to be aware that control unit terminals and components may be live to line and supply voltages.

Before working on a unit, switch off and isolate it and all other equipment within the confines of the same control cubicle. Check that all earth connections are sound.

WARNING: Suitable signs should be prominently displayed, particularly on switches and isolators, and the necessary precautions taken to ensure that power is not inadvertently switched on to the equipment whist work is in progress, or is not yet completed.

01.02.01 (A) Salely.doc 0 Bwsh Electrical Machines Ltd. 2002

C SAFETY

Training Module: 01.02.01 1 lssue: A I Date: September 2002 1 Page: 4 of 6 Adjustment and fault finding on live equipment must be by qualified and authorised personnel only, and should be in accordance with the following rules: D Read the Instruction Manual. D Use insulated meter probes. > Use an insulated screwdriver for potentiometer adjustment where a knob is not provided. > Wear non-conducting footwear. D Do not attempt to modify wiring. > Replace all protective covers, guards, etc. on completion.

Operation (L Maintenance: Engineers responsible for operation and maintenance of equipment should familiarise themselves with the information contained in the Operation & Maintenance Manual and with the recommendations given by manufacturers of associated equipment. They should be familiar also with the relevant regulations in force. 9 It is essential that all covers are in place and that all guards andlor safety fences to protect any

exposed surfaces andlor pits are fitted before the machine is started. D Ail adjustments to the machine must be carried out whilst the machine is stationary and isolated

from ail electrical supplies. Replace ail covers and/or safety fences before restarting the machine. 9 When maintenance is being carried out, suitable WARNING signs should be prominently displayed

and the necessary precautions taken to ensure power is not inadvertently switched on to the equipment whilst work is in progress, or is not yet complete.

D When power is restored to the equipment, personnel should not be allowed to work on auxiliary circuits, eg. Heaters, temperature detectors, current transformers etc.

Lifting Procedures: Ensure that the recommendations given in the manual are adhered to at all times. I I 3 CONTROL OF SUBSTANCES HAZARDOUS TO HEALTH lCOSHH REGULATIONS 1999)

3.1 Introduction I The data provided hereafter satisfies the responsibilities detailed in the COSHH Regulations 1999, and includes details of substances commonly used on standard components supplied by Brush Electrical Machines Ltd. This data is not contract specific, and therefore may include substances not used Contract specific information can be obtained from our Service Department.

ALWAYS USE SUBSTANCES IN ACCORDANCE WITH MANUFACTURERS INSTRUCTIONS.

IF AFTER APPLYING THE SUGGESTED FIRST AID PROCEDURES, SYMPTOMS PERSIST, SEEK IMMEDIATE ADVICE FROM QUALIFIED MEDICAL STAFF. NEVER INDUCE VOMITTING, OR GIVE ANYTHING BY MOUTH TO AN UNCONSCIOUS PERSON.

01.02.01 (A) Safety.doc (Q B ~ s h Electrical Machines Ltd. 2002

4 OPERATION 8 MAINTENANCE

a When working on this equipment it is important that a safe environment is achieved i.e 9 Isolate all electrical supplies including heaters. 9 Ensure adequate ventilation and lighting. 9 Use proper support for heavy items. 9 Maintain access ways. 9 Wear suitable protective clothing.

Safety guards and covers must be fitted, unless the equipment has been made safe behind the guard or cover.

I On-site safety procedures are to be followed as appropriate, in particular 'Permit To Work' type systems are be followed rigorously. Attention should be given to the advice given in Clause 2 (Health 8 Safety At Work Act (1974)) and Clause 3 (Control Of Substances Hazardous to Health (COSHH Regulations 1999)) Details of substances used on equipment that are potentially hazardous to health are detailed in Clause 3.2 and the Suppliers Data that forms part of the Operation & Maintenance Manual.

IMPROPER USE OF ELECTRICAL EQUIPMENT IS HAZARDOUS. F

PROTECTION AND MONITORING DEVICES

A WARNING: It is essential that any protection or monitoring device for use with generators or ancillary equipment should be connected and operational at all times unless specifically stated otherwise. It should not be assumed that all necessary protection and monitoring devices are supplied as part of Brush Electrical Machines Ltd. scope of supply.

Unless otherwise agreed, it is the responsibility of others to verify the correct operation of all protection and monitoring equipment, whether supplied by Brush Electrical Machines Ltd. or not. It is necessary to provide a secure environment that ensures operator safety and limits potential damage to the generator and ancillary equipment. If requested, Brush Electrical Machines Ltd. would be pleased to provide advice on any specific protection application issues or concerns.

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I GENERATOR MAINTENANCE PHILOSOPHIES I -BRUSH 8 E M Ltd.- Training Module: 01.03.01 I Issue: A I Date: September 2002 Page: 1 of 4 .

GENERATOR MAINTENANCE PHILOSOPHIES

01.03.01 (A) Generator Maintenance Philosophies.doc D Brush Electrical Machines Ltd. 2002

-1 I GENERATOR MAINTENANCE PHILOSOPHIES - nuusti B E M ~ t d . - Training Module: 01.03.01 1 issue: A CONTENTS 1 MAINTENANCE ........................................................................................................................... 3 2 MACHINE DETERIORATION ................................................................................................................... 3 3 MAINTENANCE PHILOSOPHIES ..................................... ... .................................................................. 3

3.1 Curative Maintenance 3 3.2 Preventive Maintenance 4

3.2.1 Time-Based Maintenan 4 3.2.2 Condition-Based Mainte 4

4 SENSORY PERCEPTION ...................................................................................................................... 4

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1 I MAINTENANCE I The term maintenance can be applied to a broad range of activities. in general, maintenance includes all activities necessary to enable the safe and efficient functioning of a machine or system, throughout its working life.

1 Maintenance can be said to encompass the following activities: I 1) Maintain Proper Condition

Prevent the malfunction of the machine or system. 2) Judge The Current Condition

Obtain information of the actual condition of the machine or system. 3) Recondition To The Original Condition

Maintenance must be performed to repair a fault.

Recommendations for the implementation of these activities are detailed in the Operating & Maintenance Manual, but the actual maintenance programme should be determined by the end user (or his representative) in order to reflect local site conditions e.g. operating regime, site location, operation B maintenance staff skills and availability, etc. b

2 MACHINE DETERIORATION

The factors that cause machine deterioration include: 9 When Running

9 Outgoing Load 9 Thermal Load 9 Internal Magnetic Load 9 Internal Mechanical Load, including imbalance or misalignment. 9 External Mechanical Factors, including forces exerted by the prime mover, and external

vibrations. 9 Ambient Conditions, including dust, water, corrosive atmospheres

9 At Standstill 9 External Mechanical Factors, including external vibrations. 9 Ambient Conditions, including dust, water, corrosive atmospheres

From the above it can be concluded that the machine is 'subject to wear and tear' during its entire life. irrespective of the number of hours run. Any machine will therefore need to undergo a maintenance inspection or check from time to time. The purpose of this inspection is to detect possible abnormalities that, sooner or later, may d i s ~ p t its operation, or in the case of a breakdown, determine the extent of the damage. b

3 MAINTENANCE PHILOSOPHIES

The availability of a machine has a direct influence on the wellbeing of a company. An unexpected breakdown can cause considerable inconvenience and financial loss. To keep a machine functioning efficiently throughout its working life can often cost more than the original cost of the machine itself, consequently the way in which maintenance is carried out is important. The objective is high reliability with minimum interruption of machine operation, with minimum outlay.

There are two basic maintenance philosophies that can be adopted: b

3.1 Curative Malntenance

With curative maintenance (or run-to-breakdown maintenance) a major overhaul is only performed after a breakdown. Overhauls cannot be planned and interruptions in operation occur unexpectedly.

This policy is thus only appropriate when the machine's condition is likely to deteriorate abruptly, which is not usually the case with electrical machines. Certain components can, of course, always breakdown suddenly. b

01.03.01 (A) Generator Maintenance Philosophies.doc O Brush Electrical Machines Ltd. 2002

C 1 GENERATOR MAINTENANCE PHILOSOPHIES 1 'r 1 3.2 Preventive Maintenance

With preventive maintenance, overhauls are planned ahead and take place in time to preven a breakdown. This means that the machine's condition should only be expected to deterioratt in a steady and predictable manner. For instance, the longer the machine is in operation the more likely the chance of a breakdown.

In practice, particularly for electrical machines, preventive maintenance is preferred because i is more likely to ensure dependable plant operation.

Preventive maintenance can be divided into two sub-categories, but in practice a combinatior of the two philosophies is used:

3.2.1 Time-Based Maintenance

With time-based maintenance the machine is overhauled on the basis of calenda~ time andlor hours of operation e.g. once a month, year, etc. or every so man) hours.

In most cases this is acceptable, however there is the disadvantage that some components will be replaced before the are completely worn out. For example, thc bearing would still be functioning correctly.

3.2.2 Condltion-Based Maintenance

With condition-based maintenance, the time when preventive action must bc undertaken is determined by the machine's condition. The assessment of the machine's condition must be carried out by means of monitoring equipment and skilled engineers who know how to interpret the measurements. b

SENSORY PERCEPTION

Sensory perception means: P Looking P Touching P Smelling P Listening

Sensory perception plays an Important part in maintenance, since it is often possible to detect abnormal behaviour or an abnormal situation at an early stage, without the use of any measuring equipment. b

I .03.01 (A) Generator Maintenance Philosophies.doc O Bmsh Electrical Machines Ltd. 2W2

PRINCIPLES OF AC GENERATION -BRUSH B E M Ltd.- rraining Module: 01.04.01 I Issue: A I Date: September 2002 I Page: 1 of 10

PRINCIPLES OF AC GENERATION

)1.04.01 (A) Principles Of AC Generation.doc 0 Bwsh Electrical Machines Ltd. 200:

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PRINCIPLES OF AC GENERATION -BRUSH B E M Ltd.-

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:ONTENTS I FARADAY'S LAW OF ELECTROMAGNETIC INDUCTION ............... ... ............................................. : ! THREE PHASE GENERATION ................................................................................................................. ; I GENERATOR EXCITATION CONTROL SYSTEMS .............................................................................. f

3.1 Conventional Excitation System (DC Generator Commutator Exciter) t 3.2 Static Excitation System 3.3 Brushless Excitation System E

.04.01 (A) Principles Of AC Generation.doc O B ~ s h Electrical Machines Ltd. 2002

# PRINCIPLES OF AC GENERATION I 'm A

0

Motion

Figure I: Electromagnetic Induction I Faraday's Law Of Electromagnetic Induction, illustrated in Figure 1, states that, if a conductor is moved in a magnetic field, then an electromotive force (emf) - or simply, a voltage - is induced in that conductor.

it follows that, if the ends of the conductor are connected to an external load, then an electric current, driven by that voltage, will flow from the conductor, through the load and back again.

Faraday showed that if a wire moves in a magnetic field, an artificial charge, or voltage, will be created in that wire. Faraday also showed that the magnitude of the voltage induced in the moving conductor depends on the strength of the magnetic field and the speed of movement, and on nothing else. These two laws form the whole basis of electrical power generation, both AC and DC. t

Fleming's Right Hand Rule for generators determines how this is achieved. Figure '2 illustrates the relationship between the magnetic field (North to South), direction of motion and direction of emf (voltage) induced in the conductor.

Induced emf

Figure 2: Fleming's Right Hand Rule t

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Figure 3 shows a loop of stiff wire on a shaft which can be turned. Suppose each end of the wire I connected to a slipring, insulated from the shaft, upon which there are brushes that are connected to load.

Figure 3: AC Generation - Fixed Field As the shaft is turned, one bar passes the N-pole as the other passes the S-pole. Voltage is inducec one way in one bar and the opposite way in the other. b Figure 4 illustrates how an alternating curren waveform (sine wave) IS induced in the rotating coil as it passes the fixed magnetic field.

(a) ELECTROMAGNETIC INDUCTION

Figure 4: Alternating Current b

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1 04 01 (A) Pnnc ples 01 AC Generatmn doc Q Brush Eleclncal Machines Lld 2&

Faraday's theory required only that the conductor should be moving through a magnetic field i.e. tha there should be relative motion between conductor and field. It would work just as well if the magnetic field moved past the conductor. In the arrangement shown in Figure 5 this is just what's happening.

Figure 5: Rotating Field (Permanent Magnet) In the above diagram, the stiff wire loop is fixed, and Me permanent magnet is rotated past it and inside it. As a pole passes a fixed conductor a maximum voltage is induced in it, opposite voltages on opposite sides, and they add up to give double voltage at the terminals or at the voltmeter.. In this arrangemenl no sliprings or brushes are needed which would be advantageous for a number of reasons, not leasl the reduced maintenance requirement. b

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So far only permanent magnets have been considered for producing the magnetic field. Far bette, results can be achieved by using an electromagnet, which can produce much stronger fields anc therefore much higher induced voltages (See Figure 6).

Figure 6: Rotating Field (Electromagnet) In this case however DC power must be provided to the coil which magnetises it. This can come from a battery or other DC source, but a pair of sliprings and brushes must be used to bring the battery currenl to the moving magnetising coil - called the 'field coil'. This coil is said to 'excite' the field and the whole process is called 'excitation'.

Because the field magnet is not permanent but is an electromagnet, it is possible to vary the coil currenl by a resistance and so vary the strength of the magnetic field itself. This in turn will vary the amount ol the induced voltage. b

Using this principle, it is possible for an Operator to control the machine's voltage (remotely) by varying the excitation. This is illustrated in the following diagram.

Figure 7: Voltage Control b

I .04.01 (A) Principles Of AC Generation.doc 0 Brush Electrical Machines Ltd. 2W2

2 THREE PHASE GENERATION

Figure 8: Three Phase Generation -Windings t The above diagram illustrates how the basic AC generator principles are applied to produce the three phase generation waveforms shown in Figure 9.

Figure 9: Three Phase Generation -Waveforms t

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PRINCIPLES OF AC GENERATION r 4

3 GENERATOR EXCITATION CONTROL SYSTEMS

Figure 7 showed how it would be possible (for an Operator) to control the main machine's voltage b) adjustment of the resistance which in turn varies the excitation i.e. If the Operator knows the voltage hc wants to see on a voltmeter connected to the generator output, he can adjust the resistance until the required value is achieved. This is called 'excitation control'.

To make the process automatic, an electronic device called an Automatic Voltage Regulator (AVR) 01 Excitation Controller is used to sense the output voltage and compare it with a datum which has previously been set by hand. The AVR decides whether the output voltage is correct, too high or toc low.

There commonly used types of excitation control systems for ac generators output control are:

3.1 Conventional Excitation Svstem fDC Generator Commutator Exciter)

Figure 10: Excitation System - Conventional In this system, a dc control signal is fed from the excitation control to the stationary field of the dc exciter. The rotating element of the exciter then supplies a direct current to the field winding of the main ac generator. The rotating armature of the dc exciter is either driven from the same shaft as the rotating main field of the generator, or can be on a separate motor driven shaft. In both cases, a dc commutator is required on the exciter, and brushes and sliprings (collector rings) are required on the rotating generator field to carry the main generator field current. This system is sometimes used on smaller or older machines. b

3.2 Static Excitation Svstem

Figure 11: Static Excitatioh System

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Sensing And

Main AC Exdter

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Static excitation systems obtain power from the electrical output of the generator or from the connected system to feed rectifiers in the regulating system, which in turn supply direct current to the main field winding of the generator through brushes and sliprings. b

3.3 Brushless Excitation System

Brush generators are now almost exclusively fitted with 'brushless' excitation systems in which the exciter shares a common shaft thus doing away with the need for sliprings and brushes. Since a DC generator used as an exciter would require the brushgear to rotate, the main exciter is another, but smaller, AC generator with stationary field and rotating armature. The AC output from this armature is taken converted to DC through 'rectifiers' rotating with the shaft, and then fed to the rotating field winding of the main generator.

Figure 12: Brushless Excitation System In this system the ac armature of the exciter, the rotating three phase diode bridge rectifier, and the main field of the ac generator are all mounted on the same rotating shaft system. All electrical connections are made along or through the centre of the shaft. b .

It is common to add a small second, or 'pilot' exciter (or permanent magnet generator - PMG) to excite the main exciter.

Sensing Pilot

Exciter

Main AC Exdter

Figure 13: Brushless Excitation sys temwi th Pilot Exciter b

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Figure 14: Brushless Excitation System (Without Pilot Exciter) Some Customers prefer a brushless excitation system that does not use a pilot exciter. This arrangement is illustrated in the above diagram. b

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C DAX GENERATORS

-BRUSH B E M Ltd.- rraining Module: 02.01.01 I Issue A I Date September 2002 Page 1 of 18

DAX GENERATORS

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Training Module: 02.01.01 I issue: A 1 Date: September 2002 I Page: 2 of 18 CONTENTS

........................................................................................................................................ 1 INTRODUCTION 3 .......................................................................................................... .............................. 1 . 1 Features .. 3

.................................................................................................. .......................... 1.2 Specifications .... 3 ..................................................................................................... ..................... 1.3 Configurations .... 4

2 STATOR ..................................................................................................................................................... 5 2.1 Stator Frame ...................................................................................................................................... 5 2.2 Stator Core ...................... .... ...................................................................................................... 6

..................................................................................................................................... 2.3 Stator Winding 7 ................................................................................................. ................... 2.3.1 Insulation System .. 7

2.3.2 Coil Manufacture .......................................................................................................................... 8 ............................................................................................................ 2.3.3 Winding And Connections 9

............................... ........................................................................................ 2.3.4 Winding Tests .. 9 2.4 Heaters .............................................................................................................................................. 10

3 ROTOR ..................................................................................................................................................... 11 3.1 Rotor Forging And Machining ........................................................................................................... 11 3.2 Rotor Winding ................................................................................................................................. 12 3.3 Rotor Endcaps (Retaining Rings) .................................................................................................... 12

.............................................. 3.4 Rotor Earthing Brush ...................................................................... .. 13 3.5 Rotating Rectifier Assembly ............................................................................................................ 13

................................................................ 3.6 Rotor Tests ................................................................... .. 14 I VENTILATION SYSTEM ........................................................................................................................ 16

4.1 Internal Air Circuit .............................................................................................................................. 16 4.2 Stator ................................................................................................................................................. 16 4.3 Rotor .................................................................................................................................................. 17

5 BEARINGS ............................................................................................................................................ 18 5.1 Bearings ............................................................................................................................................ 18 5.2 Monitoring Equipment .................... .. .............................................................................................. 18

2.01.01 (A) DAX Generatan.doc O Brush Electrical Machines Ltd . 2002

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1 INTRODUCTION I

I ' Figure 1: DAX Type Generator I I . I Features

Wide experience gained from the long established Brush 'DAX range of air cooled, two pole, cylindrical rotor turbogenerators has provided the following features: 9 Simple foundation design for economic and speedy civil work. > Minimum number of individual power station components, offering substantial savings on

expensive site time. % All units are fully factory tested, reducing commissioning to proving interconnections and

combined turbinelgenerator testing. > Modular construction giving a fine balance between design flexibility and standardisation

of components for fast economic production. 9 Fully developed system readily adapted to any turbine design. 9 Endframe or pedestal bearing machines available for all ratings. b

1.2 Specifications

The DAX range of turbogenerators fully complies with the provisions of the relevant British. American and International Standard Specifications. The more common standards are: 9 BS 5000 Part 2 P IEC 34.1 and 34.3 > ANSl C50.13 (Steam Turbine Drive) 9 ANSl C50.13 (Gas Turbine Drive) b

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1.3 Confiaurations

In order to accommodate various turbinelgenerator arrangements, a variety of generator driv, configurations are available which include:

Figure 2: Single End Direct Drive - Endframe Bearings

Figure 3: Double End Direct Drive - Endframe Bearings For information, DAX generators complete with basepiate, gearbox(es) and clutch(es) can also be provided.

Figure 4: Single End Drive With Baseplate, Gearbox And Clutch - Pedestal Bearings b

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? STATOR

2.1 Stator Frame

Figure 5: Stator Frame The stator frame is fabricated from mild steel plate, forming a rigid structure. Stators for endframe bearing generators have substantial mounting pads at suitable points on the underside. Holes are provided in each pad for foundation bolts and dowels. F

Afler the fabrication process is complete, the stator frame is machined concentric throughout.

Figure 6: Stator Frame Machining For Concentricity All end faces are machined at the same time to ensure correct mechanical alignment during assembly. b

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2.2 Stator Core

r6RUSH1 -BRUSH B E M Ltd.-

Figure 7: Stator Core Build

DAXGENERATORS c I 'r - ..

The core is built up from segmental laminations of low-loss, high permeability, high silicon content electrical steel.

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The laminations of the core are located by means of dovetail key bars, bolted to suitably placed members of the stator frame.

All laminations are deburred and coated with insulating varnish to minihise interlaminar contact and restrict eddy current losses.

Radial ventilation ducts are formed at intervals along the core by 'H' section steel spacers. On each side of the spacer is a thicker lamination to prevent core distortion. The spacers extend to the end of the slot teeth to increase tooth rigidity.

The core is hydraulically pressed at predetermined stages during the building operation to ensure uniform compaction, the pressure being carefully monitored.

The finished core is cramped between heavy steel end plates which are located by keys inserted in slots in the key bar lands whilst the core is under pressure. Substantial non- magnetic tooth supports transmit the pressure from the endplates to the stator teeth.

On large units the end plate and tooth supports are formed in a single integral cast unit using nonmagnetic alloy.

The core is subjected to a magnetising test prior to the insertion of the winding to check for soundness of interlaminar insulation and adequate tightness. b

'.01.01 (A) DAX Generaton.doc O Brush Electrical Machines Ltd. 2002

I DAX GENERATORS I h

2.3 Stator Windinq

The stator winding is of the two layer diamond type, half coils being used for ease of handling during manufacture and winding.

To satisfy the electrical design requirements, the winding may be of the single or multiple conductor type with parallel connections where necessary.

In order to minimise eddy current losses, each conductor is subdivided into appropriately sized laminations which are insulated from each other by a resin impregnated woven glass braid and fully transposed to minimise circulating currents. Transpositions of the endwinding or Roebel type are used as appropriate.

Figure 8: Roebel Method Of Conductor Transposition The former transposes one or more laminations at each coil nose, the connection being arranged so that, over the complete winding, a complete transposition is achieved. This is particularly suited to multi-turn coils.

On large single turn coils, it is not possible to match the number of laminations with the total number of turns per phase, and a Roebel system of transposition within the slot is used. b

2.3.1 Insulation System

The insulation system is based on a resin rich mica glass tape which, when processed, results in a high performance insulation capable of continuous operation at temperatures up to 155% (Class F). The insulation possesses high dielectric strength and low internal loss and can meet all current specifications. The resin system is thermosetting so that the resulting insulated coil sides are dimensionally stable. Additionally, it is highly resistant to most of the common electrical machine contaminants such as hydrocarbons, acids, alkalis and tropical moulds.

? . O l . O l (A) DAX Generaton.doc @ Brush Electrical Machines Ltd. 2002

C DAXGENERATORS

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I 2.3.2 Coil Manufacture

I I

Figure 9: Stator Coil Construction (Simplified) The insulated copper laminations are cut to length, stacked together and the coil ends formed into the required endwinding shape on a jig. They are then clamped tightly together, taped with an initial layer of tape and hot pressed to consolidate the conductor stack. Following this, the main insulation is applied and pressed to size. The amount of the compression is carefully controlled to ensure correct resin flow and produce a consistent high standard of void free insulation.

Flgure 10: Stator Coils I Each finished half coil is subjected to dimensional checks to ensure a correct fit in the stator slot is achieved.

To prevent corona discharge in the slot and resultant insulation damage, the surface of the coil in contact with the core is made conductive by the application of a graphite impregnated polyester tape. A silicon carbide impregnated polyester tape is applied to the coil surface immediately outside the slot to control the voltage gradient in this region. b

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2.3.3 Winding And Connections

The half coils are placed in the stator slots in two layers and wedged securely in position by synthetic resin bonded wedges prior to connection of the endwinding.

Figure 11: Inserting Wedges To Retain Stator Winding In Slots In order to withstand the forces which could arise in the event of an accidental short-circuit, the endwinding is security braced to insulated brackets supported from the stator frame. Spacer blocks are fitted between adjacent coil sides to produce a strong arch-bound, yet resilient, composite structure.

Figure 12: Stator Endwlnding Finally, the completed stator is 'baked' in an oven to fully cure the insulation.

Resistance temperature detectors and thermocouples are embedded in tht windings at selected points, and anti-condensation heaters are fitted into the Stat0 frame.

2.3.4 Winding Tests

Graded high voltage tests are carried out at stages during manufacture of the coil: and assembly of the winding. This ensures a high standard of insulation and alsl that any faults are detected at the earliest possible stage. F

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Heaters are located in the generator and exciter frames. The purpose of the heaters is to prevent moisture condensation on the windings and metal parts, which could lead to low insulation resistance or corrosion.

Access plates to the generator heaters, mounted at the ends of the stator, are provided. Exciter heaters mounted between poles at the bottom of the exciters, are accessible by removing the exciter endframe.

Prior to energising the heaters, normal safety precautions should be adopted. When the heaters are energised, it is advisable to leave a small gap (say 5mm) behind some of the access covers to allow warmed air to be replaced by cool air, thus maintaining dry air inside the machine. Rain, dust, rodents, etc. should not be allowed to enter via this gap.

A WARNING: Before energising the heaters, ensure that there ale no flammable materials in their vicinity. The heaters should always be energised when the machine is not in service. p I

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L DAX GENERATORS H

3.1 Rotor Forqina And Machininq

The rotor is manufactured from an integral forging of nickel chromium molybdenum alloy steel which is de-gassed and vacuum poured to obtain a uniform material which has excellent tensile properties.

The manufacture of the forging is closely supervised with the forgemaster to an agreed quality control procedure, including checks for freedom from porosity and for mechanical and thermal stability.

The standard forging material is suitable for use in ambient temperatures down to minus 20'C. In situations where the rotor may be subjected to lower temperatures, special materials are available.

Axial slots, to cany the winding and for ventilation, are milled on the periphery of the body of the rotor.

Figure 14: Rotor Slot Machining Axial grooves are milled along the top of both winding and ventilation slots to hold the slot closing wedges. At the exciter end, a hole is bored along the axis of the shaft to take the leads from the main exciter to the rotor field winding.

The connections to the rotor winding are brought out from the bore by radial connections. b

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1 3.2 Rotor Windinq I The rotor winding conductor material is high conductivity copper silver alloy strip.

The preformed coils are inserted into the slots, each turn being insulated from the next. Th class 'F' insulation system is moisture resistant, shockproof and capable of withstanding th high mechanical forces to which it will be subjected.

I Figure 15: Wound Rotor, 1 3.3 Rotor Endcaps (Retaininn Rinasl I After completion of the winding, the conductors are heated electrically and pressed to tht correct depth using pressing rings.

A fully interconnected damper winding is fitted into the tops of the slots and the retainin5 wedges are inserted. The rotor endwinding is braced with packing blocks between the conductors, after which the rotor endcaps are fitted. The endcaps, which retain the rotor end. winding are manufactured from austenitic nonmagnetic 18-18 manganese chromium stee which is cold expanded during manufacture to produce the high mechanical strength required.

Figure 16: Rotor End Caps The endcaps are shrink fitted to spigots at each end of the rotor body.

I Figure 17: Rotor End Caps (Fltted) b 02.01.01 (A) DAX Generators.doc 0 Brush Electrical Machines Ltd. 2W2

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3.4 Rotor Earthinq Brush

Current flowing across the oil film in a bearing can lead to the destruction of the by arc erosion in a comparatively short time. To overcome this problem a carbon rotor shaft earthing brush is fitted. The standard rotor earthing brush is approximately 25mm x 12.5mm x 40mm long, and should be changed when it has worn to approximately 14mm long.

Figure 18: Rotor Earthing Brush

Standard DAX generators have both bearings insulated. The (main) exciter end bearing earth link wire should be left disconnected (bearing bush insulated) and the non-(main)-exciter end bearing earth link connected (bearing bush uninsulated). b

3.5 Rotating Rectifier Assembly

Figure 19: Rotating Rectifier Assembly (With REFM Transmitter) Brush generators are now almost exclusively fitted with 'brushiess' excitation systems in which the exciter shares a common shafl thus doing away with the need for sliprings and brushes. Since a DC generator used as an exciter would require the brushgear to rotate, the main exciter is another, but smaller. AC generator with stationary field and rotating armature. The AC output from this armature is taken converted to DC through 'rectifiers' rotating with the shaft, and then fed to the rotating field winding of the main generator.

In this system the ac armature of the exciter, the rotating three phase diode bridge rectifier. and the main field of the ac generator are ail mounted on the same rotating shaft system. All electrical connections are made along or through the centre of the shaft

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The risk of diode failure is very remote. However, if a diode does break down, a heavy revers current will flow which is interrupted by the fuse. The adjacent diode and fuse would then be called upon to carry the whole current that was previously divided between two parallel paths Each path is designed with sufficient surplus capacity to carry the full current continuously The generator will therefore continue running as if nothing had happened.

If the more heavily loaded diode should subsequently fail, its fuse will blow, thus isolating the faulty arm completely. Again the generator can continue operating, but in this case a ripple is induced in the exciter field current which is detected by the diode failure indicator unit.

In this event, the set should be shutdown at the earliest opportunity so that the failed diodes and blown fuses can be located and replaced as follows:

Locate blown diodes and fuses using a low voltage continuity checker. It may be necessary tc separate the diodes and fuses to do this. Always replace both the blown fuse and the associated diode even if one is apparently healthy. Re-assemble any diodes that have been replaced or disturbed, ensuring proper contact with the heat sinks. Refer to the instructions on the drawings. Good joints are essent1ai.b

3.6 Rotor Tests

Figure 20: Overspeed Test Pit All completed rotors are tested in the Company's rotor overspeed test facility, which is equipped with comprehensive monitoring equipment.

The rotor is first given a low speed balance and is oversped to 20% above its normal operating speed for two minutes. The rotor is then heated to its maximum operating temperature, check balanced and the overspeed test is repeated. Finally, the balance at normal running speed is checked.

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Balance adjustment planes are provided in the rotor body itself, in the ventilating fan rings, in special balance rings, and in the main exciter diode carrier fan hub. owing overspeed testing. the rotor is subjected to high voltage tests to prove the integrity of the insulation system. t

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4 VENTILATION SYSTEM

4.1 Internal Air Circuit

Figure 22: DAX Generator Cooling air is forced around the generator by means of two axial flow fans mounted on the rotor shaft. b

4.2 - Stator

Figure 23: Basic Ventilation System I The stator core has radial ventilating ducts at intervals along the core. Most DAX units are too long for the stator cooling air requirements to be supplied by simple air gap flow, and this is overcome by arranging radial inward flow of air over sections of the stator to provide adequate airflow over the entire core length.

In this case, the space behind the stator core is divided into five compartments. I The first, third and fifth compartments are open at the top, forming the air exhaust flange. The second and fourth compartments are sealed at the outside, but are connected to the stator endwinding compartments by ducts through which they are fed with cool air in parallel with the airgap. b

02.01 .O1 (A) DAX Generaton.doc @Brush Electrical Machines Lld. 2002

DAX GENERATORS ., . . a . -BRUSH B E M Lid.- Training Module: 02.01.01 I Issue: A I Date: September 2002 1 Page:17of18

1 4.3 - Rotor The rotor is cooled by air flowing under the rotor endcap, past the endwinding and through axial cooling slots (interslots) between the winding slots.

Figure 24: Rotor Ventilation With lnterslot Cooling Only Exhaust ducts in the closing wedges of the interslots allow the air to escape at the centre 01 the rotor.

In addition to the interslots, the rotors of larger machines also incorporate cooling slots (subslots) beneath the winding slots. The cooling air escapes from the subslots through radia exhaust ducts along the length of the winding.

Figure 25: Rotor Ventilation With Subslot . And - Interslot Cooling Rotors with subslot cooling have independent cooling air paths over the endwinding tc minimise the temperature gradient across the winding. b

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02 01 01 (A) DM Generators doc 0 Brush Electrical Machlnes LtO 200

DAX GENERATORS -BRUSH B E M Ltd.- Training Module: 02.01.01 I Issue: A I Date: September 2002 I Page:IBof18

5 BEARINGS

5.1 Bearinas

Various types of bearing, including fixed profile and tilting pad, are used depending on the application.

Figure 26: Endframe Bearlng I Endframe bearing generators have specially stiffened and reinforced stator frames. A detachable solid ribbed steel plate, split on the bearing horizontal centreline incorporates the lower half bearing housing. The upper bearing housing is bolted and doweled to the bottom half housing.

The endframe is completed by a steel plate bolted'on as the upper part of the endplate. This is arranged in sections capable of easy removal to give access to the bearing. t

5.2 Monitorinq Eaui~ment

Provision is made on all bearings for temperature detectors in the bearing metal and in the oil drain.

Most types of vibration detector can be accommodated. t

02.01.01 (A) DAX Generaton.doc 0 Brush Electrical Machines Ltd. 2002

OPEN VENTILATION SYSTEMS -BRUSH B E M Ltd.- Training Module: 02.02.02 I Issue A I Date September 2002 Page 1 of 6

OPEN VENTILATION SYSTEMS

02.02.02 (A) Open Ventilationdoc Q Brush Electrical Machines Ltd. 2W3

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OPEN VENTILATION SYSTEMS -BRUSH B E M Ltd.- Training Module: 02.02.02 I Issue A I Date September 2002 Page 2 of 6 CONTENTS

......................................................................................................................... 1 INTERNAL AIR CIRCUIT 3 1.1 Stator .................................

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2.3 Filter Type 2.4 Maintenance .......... .. .......... .. ...................................................................................................... 6

I I I * OPEN VENTILATION SYSTEMS B 3

1 INTERNAL AIR CIRCUIT

DAX turbogenerators are cooled by air, either in open circuit, filter ventilated, or closed air circuit water cooled configuration.

I The generator internal air system is similar in all cases. I I Cooling air is forced around the generator by means of two axial flow fans mounted on the rotor shaft.

Flgure I: Basic Ventilation System The stator core has radial ventilating ducts at intervals along the core. Most DAX units are too long for the stator cooling air requirements to be supplied by simple air gap flow, and this is overcome by arranging radial inward flow of air over sections of the stator to provide adequate aifflow over the entire core length.

In this case, the space behind the stator core is divided into five compartments. I The first, third and fifth compartments are open at the top, forming the air exhaust flange. The second and fourth compartments are sealed at the outside, but are connected to the stator endwinding compartments by ducts through which they are fed with cool air in parallel with the airgap

02.02.02 (A) Open Ventilation.doc 0 Brush Electrical Machines Ltd. 2003

ff OPEN VENTILATION SYSTEMS

-BRUSH B E M Ltd.- Training Module: 02.02.02 I Issue: A I Date: September 2002 Page: 4 of 6

I The rotor is cooled by air flowing under the rotor endcap, past the endwinding and througi axial cooling slots (interslots) between the winding slots.

Figure 2: Rotor Ventilation With lnterslot Cooling Only Exhaust ducts in the closing wedges of the interslots allow the air to escape at the centre oi the rotor.

In addition to the interslots, the rotors of larger machines also incorporate cooling slots (subslots) beneath the winding slots. The cooling air escapes from the subslots through radial exhaust ducts along the length of the winding.

I Figure 3: Rotor Ventilation With Subslot And lnterslot Cooling I Rotors with subslot cooling have independent cooling air paths over the endwinding to minimise the temperature gradient across the winding.

02.02.02 (A) Open Ventilation.doc 0 Brush Electrical Machines Ltd. 2003

IBRUSHI I C OPEN VENTILATION SYSTEMS - a *.. -BRUSH B E M Ltd.-

Date: September 2002 Page: 5 of 6

1 2 EXTERNAL AIR CIRCUIT I I Open ventilated generators are cooled by ambient air drawn into the machine through filters and exhausted through an outlet duct connected to the stator air outlet flange.

Figure 4: External Air Clrcuits

2.1 Indoor Units

Indoor units usually have the inlet filter mounted in the wall of the power station building, the filtered air being ducted to the generator air inlet flanges.

The hot exhaust air is ducted from the generator to the outside of the building.

Air silencers are fitted into the inlet and exhaust ducts. The silencers are of the splitter type and are constructed from heavy gauge galvanised steel with a sound absorbing infil which is non-hygroscopic, vermin proof and non combustible.

2.2 Outdoor Units

Outdoor packaged units have the inlet filters supported in racks in the enclosure walls or housed in a separate air treatment module, which can be mounted above or beside the generator package.

The exhaust air is ducted through the roof of the enclosure or through the air treatmenl module. Stainless steel gravity closing louvres at the outlet inhibit the ingress of rain or snow whilst the machine is shut down.

The inlet and exhaust silencers are incorporated in the enclosure or the air treatment module.

2.3 Filter Tvues

Replaceable media filter pads or washable filter bags, protected on the outside by angled louvres, are suitable for most environments. However, certain severe climatic conditions require additional filtration or slight modifications to the air circuit.

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Inertial separators can be fitted on the air inlets to remove excessive sand or large dusl particles.

in marine environments, coalescer filters can be used to remove salt laden moisture droplets.

In areas subjected to heavy rainfall, hoods are fitted to protect the air inlets and, if necessary, the exhaust.

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In drifting snow or freezing fog, there is a danger of filter blockage. To overcome this, a temperature sensitive, motor operated recirculation system located in the inlet hood recirculates some of the hot exhaust air over the inlet filters.

Where extended filter life is desirable, self cleaning filters of the 'pulse clean' type can be provided. These are housed in a free standing module connected to the generator air inlets.

2.4 Maintenance

Generator air intake filters must be properly maintained so that the total pressure drop external to the generator taking into account all ducting, filters (maximum dirty pressure drop), silencers, louvres etc., at the inlet and outlet, must not exceed the specified system design pressure drop.

A differential pressure switch is usually connected across the filters to give a signal to notify the Operator when filter renewal is necessary.

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02.02.02 (A) Open Ventilation.doc @Brush Electrical Machines Ltd. 2003

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SH] I CLOSED AIR WATER COOLING - SYSTEMS --F ; 1 CLOSED AIR WATER COOLING SYSTEMS

12.02.03 (13) CACW Coolin~.doc @Brush Electrical Machines Ltd. 200:

:ONTENTS I INTRODUCTION ........................................................................................................................................ ? ! MAINTENANCE ......................................................................................................................................... I I PIPEWORK SYSTEMS .............................................................................................................................. I

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1- 1 CLOSED AIR WATER COOLING SYSTEMS I -BRUSH B E M Ltd.- Training Module: 02.02.03 I Issue: B I Date: October 2002 Page: 3 of 6

/ 1 INTRODUCTION I Site conditions, such as severe desert conditions, extremely salty atmosphere or unsuitably contaminated environments may necessitate the use of a closed air circuit machine.

Hot exhaust air from the generator is cooled before being returned to the generator inlet. Cooling is accomplished by means of water cooled heat exchangers containing tube nests which are arranged to permit cleaning in situ, but which can be easily removed for maintenance if required.

Figure 1: Airflow TolFrom Top Mounted Heat Exchanger I

Flgure 2: Heat Exchanger Construction b

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02.02.03 (6) CACW Cooling.doc O Brush Eleclrical Machines Ltd. 2002

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The heat exchanger is usually mounted in a sheet steel housing on top of the machine but the desigr and position of the heat exchanger assembly can be arranged to suit any specific application.

The heat exchanger tube nests are complete with flanges for connection to the water supply, and arc arranged to permit part load operation with one or more tube nests inoperative.

Figure 3: Typical Top Mounted Heat Exchanger Generators fitted with multi-section coolers can be operated at reduced load (generally 67%) with one cooler section isolated for maintenance. Care should be taken not to operate the generator with two, series connected, tube nests inoperative.

The cooler is designed to provide long and efficient service at the specified water flow rate. Reduction of water flow rate through the cooler, even if the generator is operating at part load, is no1 recommended, since low water velocity may result in tube blockage.

On units fitted with emergency doors, the generator may be operated on open-air circuit for a limited time in the event of water circulation failure. In these circumstances ALL emergency doors in the cooler and enclosure are to be open to ensure maximum air flow. If doors are opened with the generator running, outlet doors should be opened first. t

Water leaks from the heat exchanger into the generator are extremely rare. Those leaks as do Occur are invariably 'weeping' leaks at the joint between heat exchanger tubes and tubeplates. To ensure that any water released by a 'weeping' leak cannot be carried into the generator by the cooling air stream, it is usual for the 'top mounted' cooler design incorporate tube end spray baffles on each cooler nest. In addition, the tubes nests are located in deep drip trays which are drained through leak detectors.

Figure 4: Water Leak Detectors t

!.02.03 (B) CACW Coolingdoc D Brush El~tr ical Machines Lld. 2002

I 2 MAINTENANCE I I The system should be bled of air every month, or as experience dictates, to ensure that trapped air does not accumulate in the system. I It is recommended that tube bores should be inspected, by removing water boxes, at the following intervals: Sea Water: 2 years Fresh Water: 3 years WaterIGlycol: 5 years

Care is required to ensure that the fins are not damaged during the cleaning process. Normal precautions to prevent ground contamination, drain contamination and vapour build-up should be observed.

I The make-up air filter should be cleaned every 12 months. The filter should allowed to dry before refitting, ensuring that air gaps (leakage) between the filter and frame are minimised.