American Electric Power Service Corporation

Jan 26, 2010 1

Coordinating Controls across CREZ

What dials are available to the operators?

What are the hand-offs between the ISO and TO?

What does it take to implement controls in the field?

American Electric Power Service Corporation

Jan 26, 2010 2

What dials are available to the operators? Reactive Resources

Static vs Dynamic

Inductive vs Capacitive

Power Flow control

Line switching

Phase Shift Transformers

Series Capacitors

American Electric Power Service Corporation

Jan 26, 2010 3

-0.06-0.05

-0.04-0.03

-0.02-0.01

00.01

0.020.03

0.040.05

-60-50-40-30-20-1001020304050

Syncro-Phasor Voltage (high wind production)

DFW

Angle Magnitude

Houston

Valley

Mid/Ods

GenerationPower Flow

American Electric Power Service Corporation

Jan 26, 2010 4

What are the hand-offs between the ISO and TO?

Traditional

Automatic Voltage Regulator with target kV

Power Flow Controller with target MW

Alternative Approach

Reactive Reserve targets

Real Power limits

American Electric Power Service Corporation

Jan 26, 2010 5

What does it take to the implement controls?Reserves

Local real and reactive systems must have head room to respond to disturbances

Anticipation

State Estimator predicts post-contingency conditions

Preemptive scheduling of set points, so that local control can regulate back into secure positions

American Electric Power Service Corporation

Jan 26, 2010 6

Definitions for Reactive Reserve ControllerDRCS

Dynamic Reactive Compensation System

— Automation to control static and variable reactive power devices as an integral system

SSD

Static Shunt Device

— Fixed capacitor or reactor bank

American Electric Power Service Corporation

Jan 26, 2010 7

DRCS Block Diagram – SVC/STATCOM

SSD CONTROLLER

DYNAMIC VAR DEVICE(DSTATCOM or SVC)

SSD 1

SSD 2

SSD 3

SSD 4

SSD 5 SSD States

SSD Trip/Close

VSSD

SSD Bus

DRCS Bus

QDRCS

VDRCS

SCADA

Enable/Disable

Increment/Decrement

Q and V Midpoints

Scheduled V

American Electric Power Service Corporation

Jan 26, 2010 8

SSD Controller TermsVDRCS

Voltage on bus regulated by dynamic device

VSSD

Voltage on bus with SSDs

QDRCS

Reactive power output (± MVAR) of dynamic device

Increment Increase reactive power to grid (e.g. close cap or trip reactor)

Decrement Decrease reactive power to grid (e.g. trip cap or close reactor)

American Electric Power Service Corporation

Jan 26, 2010 9

SSD Controller Terms (continued)

Scheduled Voltage

Regulation setting for dynamic reactive device

Midpoint

Setting by operator for voltage or reactive power operation band

Bandwidth

Setting in the DRCS defining the high and low points of the band

+MVAr-MVAr Q_SSMPQLO QHI

Q_BW

CapacitiveInductive

set

American Electric Power Service Corporation

Jan 26, 2010 10

What Determines SSD Switching?

Dynamic reactive output (QDRCS) outside of operating band for a set time (typically minutes)

+MVAr-MVAr Q_SSMPQLO QHI

Q_BW

CapacitiveInductive

QDRCS

Increment

set

American Electric Power Service Corporation

Jan 26, 2010 11

SSD Switching Pattern in McCamey area

Three DRCSs at Crane, Rio Pecos and Friend Ranch operate locally to switch capacitors and reactors, compensating for reactive power consumption caused by intermittent power from wind

0

50

100

150

200

250

300

350

-3000 2000 7000 12000 17000 22000 27000 32000

STEP

SSD MVAR

0

200

400

600

800

1000

1200

GEN MW

CRANE RIO_PECOS FRIEND_RANCH TTL_MVAR GenMW

American Electric Power Service Corporation

Jan 26, 2010 12

Implementation of Real Power ControllersPhase Shift Transformers

Bandwidth control around a set point

Series Capacitors

Bypass controller based on target range of power flow