Generating Unit Model ValidationPolicy

approved by WECC BOT

WECC Generator Testing Task Force

History

August 10, 1996 WSCC Outage

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Simulated COI Power (initial WSCC base case)

Observed COI Power (Dittmer Control Center)

Real event

Dynamicsimulations

No confidence in dynamic database

Generator Testing

• 1997: WSCC BOT required all generators greater than 10 MVA be tested for model data validation

• Modeling and Validation WG and Control WG developed Test Guidelines

• WECC conducted two Generator Testing Workshops

• Today about 80% of generators have complied with the original testing requirement

Power System Model

Confidence today

Malin Frequency, June 14 2004 West Wing event

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COI Power, June 14 2004 West Wing Disturbance

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ActualCOI

- grid frequency

- COI power

System simulations of June 14, 2004

Real event

Simulations

Periodic Model Validation

• 1997: WSCC required periodic re-testing every 5 years

• A few generator owners have proceeded with the re-testing

• 2004: A letter from PCC and OC reiterate the need for testing, and informs about the GTTF effort of “reviewing and possibly updating generator testing requirements, in anticipation of members undertaking the 5-year retesting required by NERC.”

Generator Testing Task ForceObjectives

• Ensure and maintain the quality of the data used in power system studies

• Reduce direct costs and risks of testing to generator owners

WECC Generator Testing Policy

• Responds to emerging NERC Standards• Continues a program that has:

– Greatly improved quality and credibility of system studies

– Shown that costs are reasonable and controllable– Shown that risks are minimal and controllable– Has demonstrated substantial secondary benefits

Timeline

• Posted for comments March 8-May 8, 2005

• Re-posted for comments with technical guides September 30-November 30, 2005

• Presented to PCC and OC on March 3, 2006

• Approved by PCC and OC in June 2006

• Implementation plan approved in November 2006

Generating Unit Model Validation Policy

Generating Unit Model Validation Policy

• Applies to all generators – synchronous and induction

• Single Generator > 10 MVA or Generating Facility > 20 MVA

• Connected to WECC transmission at 60-kV and higher

Generator Owner Responsibilities

• Generating Facility Data

• Baseline Generator Testing

• Periodic Model Validation

Generating Facility Data

• The data requirements are in line with interconnection agreements: – Principal one-line diagram– Synchronous machine parameters– Excitation data (exciter, voltage regulator, PSS)– Reactive capabilities– Turbine-Governor Data– Transformer/line data

Baseline Generator Testing

Perform baseline testing and validation by simulations in PSLF or PSS/E

a) If not certified by WECC since 1997

b) Within 180 days after the new Generating Facility is released for Commercial Operation

c) Within 180 days after the existing Generating Facility restarts Commercial Operation with modified equipment

d) Within 180 days after the Generator Owner is notified by WECC that the modeled response does not match observed behavior

Baseline Generator Testing

Examples of (d)

Real eventSimulations

Baseline Generator Testing

Examples of (d)

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Real eventSimulations

Real Power Reactive Power

Model Performance Validation

Instead of full re-testing, Generator owner will perform model data validation at least every 5 years.

Performance Validation can be done by:• Performance tests (reduced scope as

compared with the baseline tests)• On-line monitoring and validation

Model Performance Validation

• Validate excitation responsedisturbance monitoring orvoltage step tests orfrequency scans

• Validate governor responsefrom observed behavior as implemented by WECC Governor Modeling Task Force

Generator Response ValidationBPA Project - 2000

~

Inject RecordedVoltage andFrequency

Compare Recordedand Simulated Power:MW and MVAR

GE PSLF Simulations

Disturbance “playback” is a standard feature in PSLF-14

Disturbance MonitoringBPA Control Area

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erat

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acity

1996:1 plant

2006:15 plants

Disturbance MonitoringThe Dalles – Original Model

Revised turbine-governor model structure to represent Kaplan turbines

Disturbance MonitoringThe Dalles – Revised Model

Disturbance MonitoringGrand Coulee – Good Model

Disturbance MonitoringCentralia – Good Model

- real power

- reactive power

-Recording-Simulations

Disturbance MonitoringBenefits

• Improved modeling

• Early detection of operational problems

• Generation performance monitoring

Relation to NERC Standards

MOD-025 – Verification of Generator Gross and Net Reactive Power Capability (– static test)

MOD-026 – Verification and modeling of Generator Excitation Systems and Voltage Controls - (under field test by NERC, expect completion by 2008)

MOD-027 – Verification and Status of Generator Frequency Response (under field test by NERC)

Relation to NERC Standards

MOD-026, -027 in field tests

Specific guidelines for test and re-validation

Periodic Model Validation

NoneBaseline TestReference Model Data

Required, but not standardized

StandardizedData Requirements

NERCWECC

MOD-025 approvedReactive Limit Verification