Power Quality and

Renewables

2007 PCEA Conference

S&C Electric Company

Presentation OverviewPresentation Overview

Overview of Large Inverter Technology How Large Inverters Work Overview of Large Inverter Applications Specific Applications for Large Inverters

Overview of Large Inverter Technology How Large Inverters Work Overview of Large Inverter Applications Specific Applications for Large Inverters

Powerful Mega-Watt Size InverterPowerful Mega-Watt Size Inverter

IGBT Technology

High Frequency

PWM

Produces and/or alters an AC Sine Wave

S&C TWO +1 MVAR Inverter BlocksS&C TWO +1 MVAR Inverter BlocksCommon Inverter can be Utilized for various Power Quality Applications:

Real Power Reactive Power (Capacitive or Inductive) Reactive & Real

Power Voltage Sag

Mitigation Power Factor

Correction Convert DC to AC

Inverter to provide capacitive & reactive VARS:Inverter to provide capacitive & reactive VARS:

Through inverter function (DC to AC), the Through inverter function (DC to AC), the AC Inverter AC Inverter VoltageVoltage can be controlledcan be controlled

If Vinverter If Vinverter > VutilityVutility then then DSTDSTATCOM looks like a ATCOM looks like a capacitor on systemcapacitor on system

Vary Vary VacVac to control reactive power to control reactive power Vary phase angle to control real powerVary phase angle to control real power

Inverter for Voltage Boost:Inverter for Voltage Boost:

Injects capacitive reactive current to boost voltage at the facility during a utility sag

Voltage is boosted across the source impedance

Injects capacitive reactive current to boost voltage at the facility during a utility sag

Voltage is boosted across the source impedance

Load CurrentLoad CurrentDSTATCOM Capacitive CurrentDSTATCOM Capacitive Current

Inverter to provide voltage boost:Inverter to provide voltage boost:

Sag conditions Load at unity pf

Sag conditions Load at unity pf

DSTATCOM TWO +1 MVAR Blocks

Utilized for various MV applications:C&I PQ

- MV UPS- Voltage Sags- Power Factor- Voltage Flicker

Wind- Power Factor- Voltage Mode- LVRT-ZVRT

SolarUtility Peak ShavingUtility Voltage Support

PureWave Inverter Based SolutionsPureWave Inverter Based Solutions

Uninterruptible Power Supply (UPS) Distribution Static Compensator

(DSTATCOM) for Voltage Sags, Power Factor and Flicker Mitigation

DSTATCOM for Distributed Voltage Support Distributed Energy Storage System (DESS)

DSTATCOM + NaS DSTATCOM for Wind Farm Interconnect DSTATCOM for Photo Voltaic Interconnect DSTATCOM with Ultra Caps for Island Wind

Farms

Uninterruptible Power Supply (UPS) Distribution Static Compensator

(DSTATCOM) for Voltage Sags, Power Factor and Flicker Mitigation

DSTATCOM for Distributed Voltage Support Distributed Energy Storage System (DESS)

DSTATCOM + NaS DSTATCOM for Wind Farm Interconnect DSTATCOM for Photo Voltaic Interconnect DSTATCOM with Ultra Caps for Island Wind

Farms

Medium-Voltage PureWave UPS Systems for C&I ApplicationsMedium-Voltage PureWave UPS Systems for C&I Applications

System from at 5 to 34.5 kV

Ratings from 2.0 to 16 MW

System from at 5 to 34.5 kV

Ratings from 2.0 to 16 MW

Pharmaceutical 5 MVA to 7.5 MVA UPS at 4,160 VPharmaceutical 5 MVA to 7.5 MVA UPS at 4,160 V

FAB Manufacturer15.0-MVA @12.47 kVFAB Manufacturer15.0-MVA @12.47 kV

Rating: 2 x 10,000 kVA UPS @12.47 kVWith Source Transfer and Back-up Generation

4 2.1 MW Diesel Generators

Critical Power SystemCritical Power System

S&C DSTATCOM for Dynamic VAR Support, PF, Flicker & Sag MitigationS&C DSTATCOM for Dynamic VAR Support, PF, Flicker & Sag MitigationWhy Inverter Based Compensator ?

DSTATCOM has fastest speed of response

DSTATCOM transient overload allows it to deliver > nameplate rating even for reduced system voltages

DSTATCOM operates down to 15% retained system voltage

DSTATCOM will operate at 0 voltage with external energy source

An inverters MVAR output decreases linearly with voltage

Why Inverter Based Compensator ?

DSTATCOM has fastest speed of response

DSTATCOM transient overload allows it to deliver > nameplate rating even for reduced system voltages

DSTATCOM operates down to 15% retained system voltage

DSTATCOM will operate at 0 voltage with external energy source

An inverters MVAR output decreases linearly with voltage

DSTATCOM Dynamic Capability DSTATCOM Dynamic Capability

-100

-50

0

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100

150

200

250

300

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00

Seconds

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Ouput Comparison SVC vs DSTATCOM with 330% Short Term Overload

0.00

0.50

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1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3

Voltage (p.u.)

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DSTATCOM

SVC

DSTATCOM Dynamic Voltage Support DSTATCOM Dynamic Voltage Support

DSTATCOM MVAR Output

when needed most via high short termoverload capability

For transient / dynamicevents when needed most, the comparison is remarkable

DSTATCOM MVAR Output

when needed most via high short termoverload capability

For transient / dynamicevents when needed most, the comparison is remarkable

SVC vs. DSTATCOMSVC vs. DSTATCOM

Range of Operation

Distributed Energy Storage System (DESS) PUREWAVE DSTATCOM & NaS BatteryDistributed Energy Storage System (DESS)

PUREWAVE DSTATCOM & NaS Battery

Utility energy storage for peak shaving applications Ability to inject MWs of medium voltage energy

into grid during Peak Loading Ability to inject energy for up to 8 hours Recharge system during off peak hours Full cycle efficiencies of over 75% 15 year battery life

Utility energy storage for peak shaving applications Ability to inject MWs of medium voltage energy

into grid during Peak Loading Ability to inject energy for up to 8 hours Recharge system during off peak hours Full cycle efficiencies of over 75% 15 year battery life

PureWave DESS Installation1.2Mw, 7.2MwH NAS BatteryPureWave DESS Installation1.2Mw, 7.2MwH NAS Battery

Dynamic VARs from DESSDynamic VARs from DESS

VARs Available All the Time

Maximum Available VARs from a 1.2 MW DESS

-1,400-1,200-1,000

-800-600-400-200

0200400600800

1,0001,2001,400

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Time of Day (example)

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kWATTS+/- kVARS

xCharge Period

Available VARS

Discharge Period

Distributed Energy Storage System - NaSBattery Project 1 MW for 8 HoursDistributed Energy Storage System - NaSBattery Project 1 MW for 8 Hours

TransmissionSubstation

Commercial

Industrial

Wind Generation

DistributionSubstations

11stst Peak ShavingPeak Shaving22ndnd Load SeparationLoad Separation33rdrd Power QualityPower Quality

DSTATCOM for Wind PlantDSTATCOM for Wind Plant

DSTATCOM for Wind Farm Dynamic VARs and LVRT DSTATCOM for Wind Farm Dynamic VARs and LVRT

Feeder Feeder collectorscollectors

Sub station collection busSub station collection bus

HighHigh--voltage voltage gridgrid

DSTATCOMDSTATCOM

VISTAVISTA

VISTAVISTA

VISTAVISTAVISTAVISTA

VISTAVISTA

VISTAVISTA

S/CS/C

9 MVAR

S/CS/C

9 MVAR

S/CS/C

Wind Farm +/-12/39 MVARWind Farm +/-12/39 MVAR+/-12/39 MVAR DSTATCOM-LV

Pad-mount transformers (2 MVA)MV Vista Feeding transformers

+/-6 MVAR Follower Enclosure

+/-6 MVAR Lead Enclosure (with control room)

DSTATCOM Arrangement in ISO Enclosure

Operation with Switched Capacitor BanksOperation with Switched Capacitor Banks

+16+16

00

--1616

DSTATCOM Output (MVAR)DSTATCOM Output (MVAR)

Switched Cap BanksSwitched Cap Banks

+60+60

+40+40

+20+20

00 Cap Bank 1Cap Bank 1

Cap Banks (All 20 MVARCap Banks (All 20 MVAR))Cap Bank 3Cap Bank 3

Total Continuous Output Total Continuous Output

DSTATCOM Short DSTATCOM Short Term Overload of Term Overload of 330% can be used 330% can be used instantaneously, instantaneously, anywhere along anywhere along curve to boost or curve to boost or buck VARs for 2 buck VARs for 2 seconds then backs seconds then backs down over the next down over the next 2 seconds to 100% 2 seconds to 100% outputoutput

Note: Cap Bank size Note: Cap Bank size must be less than the must be less than the range of the range of the DSTATCOM DSTATCOM (~75%)(~75%)

Cap Bank 2Cap Bank 2

ESA Electronic Shock AbsorberESA Electronic Shock Absorber

DSTATCOM with real energy source Smooth out sudden power increases and decreases from the

wind farm to the utility grid Utilizes Ultra-capacitors to absorb or deliver power Ultra-capacitors are at 50% charge level Continuously manages power Injects real energy for up to 15 seconds Performs as a DSTATCOM for power factor and voltage

support providing capacitive or inductive reactive power Typically sized to be 15% to 25% of the wind farm MW

DSTATCOM with real energy source Smooth out sudden power increases and decreases from the

wind farm to the utility grid Utilizes Ultra-capacitors to absorb or deliver power Ultra-capacitors are at 50% charge level Continuously manages power Injects real energy for up to 15 seconds Performs as a DSTATCOM for power factor and voltage

support providing capacitive or inductive reactive power Typically sized to be 15% to 25% of the wind farm MW

ESA Electronic Shock AbsorberESA Electronic Shock Absorber

ESA Trailer LayoutESA Trailer Layout Energy StorageUltracapacitors

DSTATCOM for Photovoltaic ApplicationsDSTATCOM for Photovoltaic Applications Photovoltaic devices use semiconducting materials to

convert sunlight directly into electricity. Solar radiation, which is nearly constant outside the

Earth's atmosphere, varies with changing atmospheric conditions (clouds and dust) and the changing position of the Earth relative to the sun.

Almost all U.S. regions have useful solar resources that can be accessed.

Photovoltaic devices use semiconducting materials to convert sunlight directly into electricity.

Solar radiation, which is nearly constant outside the Earth's atmosphere, varies with changing atmospheric conditions (clouds and dust) and the changing position of the Earth relative to the sun.

Almost all U.S. regions have useful solar resources that can be accessed.

Photovoltaic ProjectPhotovoltaic Project

One major US developer is projecting 250MW of PV within three years.

The output of these large PV systems will be 600V tp 1000V DC

Small systems will be in the 300KW to 1 MW range Systems exist that are 40MW. Required output will be 480V 3 Phase AC

One major US developer is projecting 250MW of PV within three years.

The output of these large PV systems will be 600V tp 1000V DC

Small systems will be in the 300KW to 1 MW range Systems exist that are 40MW. Required output will be 480V 3 Phase AC

10 MW Solar Park10 MW Solar Park

12 MW Solar Park 12 MW Solar Park

First Automatic Electric WindmillFirst Automatic Electric Windmill

Charles F. Brush built 1887-1888 Cleveland, Ohio 12,000 watt 144 blades - cedar 50Ft diameter charged batteries in

basement of house ran for 20 years Scientific American

Dec. 20, 1890

Charles F. Brush built 1887-1888 Cleveland, Ohio 12,000 watt 144 blades - cedar 50Ft diameter charged batteries in

basement of house ran for 20 years Scientific American

Dec. 20, 1890