Generating Unit Model Validation
Policy
approved by WECC BOT
WECC Generator Testing Task Force
History
August 10, 1996 WSCC Outage
4600
Observed COI Power (Dittmer Control Center)
4400
Real event
4200
4000
Simulated COI Power (initial WSCC base case)
4600
4400
Dynamic
simulations
4200
4000
0
10
20
30
40
50
60
Time in Seconds
No confidence in dynamic database
70
80
90
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
- grid frequency
System simulations of June 14, 2004
Malin Frequency, June 14 2004 West Wing event
60.1
- COI power
60
COI Power, June 14 2004 West Wing Disturbance
6000
5500
Actual
Malin Freq
59.8
5000
59.7
4500
Power [MW]
Frequency [Hz]
59.9
59.6
Actual
COI
4000
3500
59.5
0
5
10
15
20
25
30
35
40
45
Time [sec]
Real event
50
55
60
65
70
75
3000
2500
2000
Simulations
0
5
10
15
20
25
30
35
40
Time [sec]
45
50
55
60
65
70
75
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 Force
Objectives
• 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 event
Simulations
Baseline Generator Testing
Examples of (d)
Real Power
Reactive Power
-670
400
5
10
15
20
25
30
35
40
-690
350
Q (MVar)
-710
P (MW)
300
-730
38MW
250
-750
200
55MW
-770
Q4_ref
P4_ref
-790
t (s)
Real event
Simulations
P4_sim
Q4_sim
150
5
10
15
20
t (s)
25
30
35
40
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 response
disturbance monitoring or
voltage step tests or
frequency scans
• Validate governor response
from observed behavior as implemented by
WECC Governor Modeling Task Force
Generator Response Validation
BPA Project - 2000
GE PSLF Simulations
Inject Recorded
Voltage and
Frequency
Compare Recorded
and Simulated Power:
MW and MVAR
~
Disturbance “playback” is a standard feature in PSLF-14
Generating Capacity
Disturbance Monitoring
BPA Control Area
25000
20000
15000
10000
5000
0
1996:
1 plant
2006:
15 plants
Disturbance Monitoring
The Dalles – Original Model
Disturbance Monitoring
The Dalles – Revised Model
Revised turbine-governor model structure to represent Kaplan turbines
Disturbance Monitoring
Grand Coulee – Good Model
Disturbance Monitoring
Centralia – Good Model
- real power
- reactive power
-Recording
-Simulations
Disturbance Monitoring
Benefits
• 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
WECC
NERC
Data Requirements
Standardized
Required, but
not standardized
Reference Model Data
Baseline Test
None
Periodic Model
Validation
MOD-026, -027 in
Specific
guidelines for test field tests
and re-validation
Reactive Limit
Verification
MOD-025 approved