Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 ....
Transcript of Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 ....
![Page 1: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/1.jpg)
Lecture #2
Introduction to Power System Operation and Control using ARISTO
Davood Babazadeh
2015-09-04
![Page 2: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/2.jpg)
2
Outline
Power system basics
Operational states
Power system control
– Active power and frequency
– Reactive power and voltage
Lab session
![Page 3: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/3.jpg)
3
Course road map
![Page 4: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/4.jpg)
Transport of electric power
Apparent power (Complex power) (S) [VA] – S=VI*=P+jQ – Electric power P [W] – Reactive Power Q [VAR]
Two ways to increase the transported power – Increase current I
• Larger conductor cross-section – Increase voltage U
• More insulation
Two ways to transport electricity – Alternating current (AC) – Direct current (DC)
4
![Page 5: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/5.jpg)
Power network structure
Transmission system – all major generating stations and main
load centers – voltage levels (typically, 230 kV and
above).
Sub-transmission system – transmits the transmission substations
to the distribution substations. – Large industrial customers
Distribution system – power to the individual customers – between 4.0 kV and 34.5 kV
5
![Page 6: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/6.jpg)
6
Operational states
Normal state, all system variables are within the normal range
Alert state, security level falls below a certain limit of adequacy because of a disturbance • generation shifting (security dispatch) , Increased reserve
Emergency state, severe disturbance • fault clearing, generation tripping, load curtailment
In extremis, cascading outages • load shedding and controlled system separation
Restorative state, control action is being taken to reconnect all the facilities and to restore system load.
Emergency
Alert
Normal
In Extremis
Restorative
![Page 7: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/7.jpg)
Operational requirement
Follow the change in the load demands
Supply energy at minimum cost and environmental impact.
Power quality
– Frequency
– Voltage
– Level of reliability.
7
![Page 8: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/8.jpg)
Why constant frequency
Frequency fluctuations are harmful to electrical appliances.
– Speed of three phase ac motors proportional to the frequency. (N=120f/p)
– The blades of steam and water turbines are designed to operate at a particular speed. Frequency variation leads to speed variation and results in mechanical vibration
8
![Page 9: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/9.jpg)
Why constant voltage
Over voltage and under voltage
– Electric motors will tend to run on over speed when they are fed with higher voltages resulting vibration and mechanical damage.
– Over voltage may also cause insulation failure.
– For a specified power rating, lower voltage results in more current and this results in heating problems. (P=VI)
9
![Page 10: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/10.jpg)
Control parameters
Active Power and Frequency – Balance of load and generation
– Load-Frequency Control
Reactive Power and Voltage – Automatic voltage regulator
– capacitors and reactors
– Tap-changing transformers
10
![Page 11: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/11.jpg)
Load & generation balance
Match between electric load and generation Frequency is an indication Balanced system, 50/60 Hz Net power surplus , frequency increases Net power shortage, frequency decreases
Generation Load
ΔP Δf
11
![Page 12: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/12.jpg)
Generator
Generation side Control Demand side control
Governor Δf
Primary Control
Δf
Secondary Control
AGC/LFC ΔPtie
Connection and Tripping of power
Operator
UFLS
UCT
UUFLS
USec
U pri
dfdt
Emergency Control
Power System
f
Frequency control actions
12
![Page 13: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/13.jpg)
13
Primary Frequency Control
• Generation is controlled by mechanical output of the prime mover
• The speed governor senses the change in speed (frequency)
• Actions taken within 5 – 30 seconds by generator droop control
![Page 14: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/14.jpg)
14
Need of primary control reserves
UCTE 3000 MW (Continental Europe) – 3000 MW or equivalent of two 1500 MW nuclear plants or
lines trip at the same time
Eastern Interconnection (USA) – 3000 MW = largest interconnection
NORDEL (North Europe) – Continuous control = 600 MW/0.1 Hz – Frequency response = 1000 MW, if frequency drop to
49,5 – 49,9 Hz
![Page 15: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/15.jpg)
15
Secondary control reserves Should reset the primary control reserves in 5 – 15 minutes to be ready for next disturbance Should correct the frequency deviation within allowable limit
• +/- 0.1 Hz in Nordel • +/- 0.2 Hz in UCTE
![Page 16: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/16.jpg)
16
Supplementary/Secondary Control
Frequency deviation feedback PI or I controller Connected to economic dispatch system
![Page 17: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/17.jpg)
Under frequency Load Shedding (UFLS)
To prevent extended operation of separated areas at low frequency, load shedding schemes are employed. A typical scheme for USA:
• 10% load shed when frequency drops to 59.2 Hz • 15% additional load shed when frequency drops to 58.8 Hz • 20% additional load shed when frequency reaches 58.0 Hz
17
![Page 18: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/18.jpg)
Example
18
![Page 19: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/19.jpg)
Voltage Control
Control of voltage levels is carried out by controlling the production, absorption, and flow of reactive power
Generating units provide the basic means of voltage control. synchronous generators
– can generate or absorb Q depending on excitation
– automatic voltage regulator continuously adjusts excitation
to control armature voltage
– primary source of voltage support
19
![Page 20: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/20.jpg)
Voltage Control
Additional means are usually required to control voltage throughout the system:
– sources or sinks of reactive power, such as shunt capacitors, shunt reactors, synchronous condensers, and static var compensators (SVCs)
– line reactance compensators, such as series capacitors
– regulating transformers, such as tap-changing transformers and boosters
20
![Page 21: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/21.jpg)
Example: Shunt Compensation
21
a) shunt compensation
b) phasor diagram without compensation
c) phasor diagram with compensation
![Page 22: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/22.jpg)
Introduction to LAB 1
Using ARISTO
22
![Page 23: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/23.jpg)
Aim of Lab1
To introduce – Basic operational phenomena in a typical power system
– Corresponding countermeasures
– Real time simulations
– Dynamic behaviour of power system
23
![Page 24: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/24.jpg)
What is ARISTO
The ARISTO system is a fast, interactive power system dynamics simulator for learning and analysis.
The simulator is capable of real-time simulation of large systems.
Simulation of very large systems is possible with a slower simulation speed.
The phenomena to be simulated are:
• Transient stability. • Long term dynamics. • Voltage stability.
24
![Page 25: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/25.jpg)
System Overview
25
![Page 26: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/26.jpg)
26
What can be modeled?
1 s 10 -2 10 -3 10 -4 10 10 -1 10 2 10 3
Load Frequency Control
Turbine & Boiler Control
Generator Excitation Control
Special Protection Systems
Protective Relay Systems
HVDC & SVC
Surge
Harmonics
Frequency Variations
Power Swing
Sub Synchronous Resonance
Equipment
Phenomena
![Page 27: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/27.jpg)
27
Exercises - Scenarios
Task 1: Voltage Support • Injection / Consumption of reactive power
Task 2: Voltage Collapse in a power system (N-1 Operation) • Operation of Line Distance Protection (LDP) relays
• Islanding of power system due to voltage instability
Task 3: Frequency control along with load shedding • Primary Frequency Control (Governor Droop Characteristics)
• Secondary Frequency Control (Manual)
• Under Frequency Load Shedding
![Page 28: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/28.jpg)
28
Exercises - Model • Simulations are performed with NORDIC 32 test system
![Page 29: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/29.jpg)
29
Nordic 32 system description
Buses 32 Buses 21 PV buses, 10 PQ buses, 1 Slack bus 19 buses 400kV, 11 buses 135kV, 2 buses 220kV Transmission lines 52 Lines 33 Lines in 400kV, 17 Lines in 135kV and 2 Lines in 220kV Loads 21 buses have loads connected to them Generators 39 Generators 23 Hydro stations, 15 Thermal Stations and 1 Synchronous compensator 21 buses have generators Shunts 22 buses have shunts connected 3 buses have both shunt reactors and shunt capacitors 11 buses have shunt reactors alone, 8 buses have shunt capacitors alone
MittSV
Norr ExternActive Production: 3778 MWActive Load: -1181 MW
Active Production: 3429 MWActive Load: -6084 MW
Active Production: 2301 MWActive Load: -2300 MW
Active Production: 1753 MWActive Load: -1391 MW
2412 MW
1 MW
340 MW
![Page 30: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/30.jpg)
30
Exercises - Outcome
• Getting started with ARISTO real time simulator
• Operation and control of a typical power system
• Voltage stability
• Operation of Line Distance Protection (LDP) relays
• Primary and Secondary Frequency control
![Page 31: Introduction to Power System Operation and Control · Introduction to LAB 1 . Using ARISTO . 22 . Aim of Lab1 . To introduce – Basic operational phenomena in a typical power system](https://reader030.fdocuments.us/reader030/viewer/2022040914/5e8b5a985b5e2e5c3d0233b9/html5/thumbnails/31.jpg)
Question?
31