Transcript Instructions

VRT Study
Update
José Conto
ERCOT System Planning
Voltage Ride-Through Boundaries For WTG
Ref.: ERCOT Op. Guides, Section 3.1.4.6.1
May 2010
2
Dynamic Studies
System Planning
Wind Turbine Generator Types
Type I
Type II
Type III
Type IV
NEG Micon NM72
0.7 MW
Vestas V47
660 kW
GE
1.5 MW
Kennetech 33-MVS
400kW
Mitsubishi
MWT1000A
1 MW
Vestas V66
1.75 MW
Vestas V90
1.8 /3 MW
Siemens
2.3 MW
Bonus
1.3 MW
Vestas V80
1.8 MW
Gamesa G80, G83 &
G87
2.0 MW
Clipper C93
2.5 MW
Vestas V82
1.65 MW
Suzlon S88
2.1 MW
Mitsubishi MWT-92/95
2.4 MW
Vestas NM72
1.65 MW
1404 MW
16.5 %
Nordex N80
2.5 MW
463 MW
5.5 %
5042 MW
59.3 %
1598 MW
18.7 %
* 2009 Fall case
May 2010
3
Dynamic Studies
System Planning
The VRT Study
Identify system reliability risks associated with existing wind plants
that do not have full VRT capabilities.
– Phase I
• Dynamic simulations utilizing existing ERCOT model data set (PSS®E
ver. 30)
– Phase II
• Verify wind plant modeling and develop model improvements as
necessary
• Collect modeling data directly from wind plant owners
– Phase III
• Dynamic simulations utilizing updated models based on model
verification (PSS®E ver. 31)
May 2010
4
Dynamic Studies
System Planning
Phase II
• Wind plant modeling outcome –
– Collection of actual field data needed for plant modeling of all the wind plants
in ERCOT
– Methodology to develop a collector system equivalent
and wind turbine aggregation
 Steady State test
• Active and Reactive Power Loss of wind plant
• Active and Reactive Power Exchange at POI
 Short-Circuit test
• Short-Circuit Current Levels at POI for 3-Phase Faults
 Dynamic Response test
• Electrical Power Output Response
• Terminal Voltage Response
• System Frequency and Voltage Response
May 2010
5
Dynamic Studies
System Planning
Phase III
 Dynamic simulations utilizing updated models. HWHL and HWLL cases
rerun.
 Scenarios:
1. HWLL case w/no conventional generation in West Texas
2. HWHL case w/dynamic motor load modeled in West Texas
3. HWLL case w/no conventional generation and w/dynamic motor
load modeled in West Texas
4. Investigation of the impact of wind generator terminal and/or POI
voltage set point on VRT response
5. Investigation of problematic contingencies to develop potential
solutions that ensure an operational margin
6. Application of the updated wind models to an ERCOT 2010 base
case
May 2010
6
Dynamic Studies
System Planning
Phase III Status
• Simulations for HWHL and HWLL cases completed.
• Simulations for scenarios 1,2 and 3 completed. Results are being
finalized.
• Scenarios 4 and 5 are under investigation.
• Scenario 6 has not started.
• Final Report outline has been developed and certain sections are
currently under documentation. Presentation scheduled for June
ROS meeting.
May 2010
7
Dynamic Studies
System Planning
No Conventional Generation in West Texas – Stability Limit?
• Currently, no small signal stability limit on West to North when no
conventional generation is on-line in the West; thermal limits only
• Based on study with updated models, voltage stability limit has
potential to bind before thermal limits with no conventional
generation on-line
• The critical contingencies: double circuit with and without fault and
line-to-ground fault with breaker failure.
• Reduction in output at any of the units west of the West-to-North
interface eliminate the non-convergence problem.
• ERCOT Operations will implement this new conditional stability limit
ASAP.
May 2010
8
Dynamic Studies
System Planning
Far West Texas – Stability Limit?
• Far West interface composed of three 345 kV lines west of Morgan
Creek substation.
• West-North interface flow kept at ~1976 MW.
• A stability limit is reached when the Far West interface flow is about
1300 MW (~ 1150 MW Far West wind output.)
• Thermal overload binding before reaching the stability limit.
• ERCOT PI data for the period 7/1/2009 to 5/1/2010 indicates that
the highest flow on the interface into Morgan Creek was 1140 MW
and that the W-N stability limit was constraining most of the time
when high transfer into Morgan Creek was observed.
• A stability limit will not be implemented for the Far West.
May 2010
9
Dynamic Studies
System Planning
José Conto
Supervisor, Dynamic Studies
System Planning
Electric Reliability of Texas, Inc.
512-248-3141
[email protected]
May 2010
10
Dynamic Studies
System Planning