Dynamic VAR’s [D-VAR]

What are D-VAR Devices?

• Dynamic VARs… Fully integrated modular STATCOM

with proprietary 3X overload

• Instantaneously injects precise amounts of reactive

power into a network

• Can be seamlessly integrated with static shunt devices

as part of a larger solution

Ref. American Superconductors

Transmission Problems That D-VAR Can Solve:

•Voltage Stability / Voltage Collapse -•Uncontrolled rapid decline in system voltage

• Steady State Voltage Regulation -• Wind farms, radial lines, etc...

• Import/ Transfer Capability Restrictions -• Limited ability to reliably import, export, or transfer power

• Mitigate voltage flicker/ power quality -• Wind farms, industrial facilities

Ref. American Superconductors

Single Phase DC/AC Inverter

• Devices 1A, 1B, 2A and 2B are IGBT’s acting as fast switches

• Capacitors hold DC charge

• Lf and Cf are AC smoothing filter components

Lf

Cf

1A

1B

2A

2B

ACDC

+

-

Ref. American Superconductors

Each D-VAR system has continuous reactive power… with temporary overload capability up to 3 times its continuous rating. Each phase is individually controlled.

Proprietary Power Electronics Technology

Ref. American Superconductors

D-VAR Unit

Southold

Tiana

Southampton

Bridgehampton

Riverhead

Buell

Generating

Hero

Orient Point

Tuthill

Mattituck

Peconic

East HamptonAmagansett

Installation SiteDouble Circuit 69kV fault

Areas of Voltage Collapse Concerns

East End of Long Island

Ref. American Superconductors

To East Hampton Diesels

8 MVAD-VAR Inputs to DVAR

for Voltage Control

VT

480-13800 VPadmount

Transformers

69 kV

13.8 kVLoad

Load

VT

13.8 kV

To BuellTo Bridgehampton

Easthampton

Proposed Solution for the East End Voltage Issues 8 MVA D-VAR Installed at Bridgehampton

Ref. American Superconductors

Stony Hill

Plumtree

RockyRiver

WestBrookfield

BatesRock

Shepaug

CarmelHill

LongMountain

FrostBridge

G

G

G

345 kV115 kVHydro GeneratorSubstation

Trans. CapacitorDistrib. Capacitor

D-VAR TM

Northeast Utilities Danbury AreaD-VAR solution by American Superconductors

SW Connecticut Imports

Pe

r U

nit V

olta

ge

s

Problem

Solution

Northeast Utilities Danbury AreaComparison of Load-flow Results

Ref. American Superconductors

D-VAR™ Solution’s Dynamic Voltage Support Provides a total of -48 MVAR/+84 MVAR

28 MW

26 MW

600V

600V 115 kV34.5 kV

T160/90 MVAwith LTC

28 units

26 units

97% Lagging PF

97% Lagging PF

26 MW

600V

26 units

34.5 kV UDGcollectorsystem

97% Lagging PF

UtilityInterconnection

Point

8/24 MVARD-VAR

VTs

8/24 MVARD-VAR

Dynamic Capacitor Banks 2 x 18 MVAR = 36 MVAR

D-VARs . Dynamic 2 x 8 x 3 = 48 MVAR

1200 AmpBreaker

4x2500 KVA 34500-480Vpadmount

transformers

JoslynVBM

Switch

JoslynVBU

Switch

The dynamic MVARs are sized to prevent the wind farm from tripping off-line for the faults that the utility specified.

9 X 3.6 MVAR

Caprock Wind Farm, New Mexico; D-VAR built by American Superconductors