OWG UFLS Survey and Power Factor review
Download
Report
Transcript OWG UFLS Survey and Power Factor review
UFLS Survey &
Power Factor Review
April 23rd OWG
2014 UFLS Survey – Summary of Changes
Previous Surveys
2014 Survey
PRC -007
Op Guides 2.6.1 (2)
TRE
ERCOT & TSPs
Reported by pss/e
Bus number
Mid April
Submit 30 days after
survey date
Threshold summary
Bus Detail Not Required
5/13 11:00 (OBO – time)
Submit No Later Than
6/13/14
Update TAC when
compliance is achieved.
2
PRC 006-01 & PRC-007-0
NERC PRC Standards 6&7
PRC-007-0
Effective 4/1/05, Inactive 9/30/13
Replaced with PRC-006-1
PRC-006-1 Enforceable 10/1/13
PRC-006-0 NERC approved
FERC did not remand or approve Version 0
ERCOT Planning Functions & Dynamics WG Processes
ERCOT 5 year Review of UFLS Program
Data Collection & Retention
Planning Guide §6.2.3 Dynamics Data Requirements for T/DSP
Dynamics Working Group Procedures
3.4.1 UFLS Relay Data collection
4.2.2 Stability Book
3
Operating Guides Section 2.6 UFLS Requirements
2.6.1(1) at least 25%...
2.6.1(2)
With the assistance of applicable Transmission Service Providers
(TSPs), ERCOT will, prior to the peak each year, survey each
Distribution Service Provider’s (DSP’s) compliance with the
automatic Load shedding steps above, and report its findings to the
Technical Advisory Committee (TAC). For minimum compliance,
DSPs are obligated to meet the prescribed percent values at all
times. It is not permitted to use rounding to meet the minimum.
ERCOT will direct a review of the automatic firm Load shedding
program whenever warranted by conditions. At a minimum, this
review will follow the Reliability and Operations Subcommittee
(ROS) directed dynamic simulations of automatic firm Load
shedding conducted at five-year intervals beginning in the Summer
of 2001.
4
UFLS Program 2015
Additional Information
Incorporate tenets in other sections of 2.6.1
Location / Zone
Rolling / Re -arming
Responsibility Transfers (Limited to Compliance)
Limited
Attestation Only
Less
Remove Survey
Monitor Performance
5
Power Factor Load Flow Studies
Annual Load Data Request
Distribution Power Factors Submitted to ERCOT Via ALDR
Expressed on high side
Drawing VARs is positive, providing VARs negative
Incorporated in SSWG /Planning Base Cases
Confirmation
Every study preformed on the ERCOT System
Assumes Appropriateness & Accuracy in Load Forecasting
Operations Horizon – less likely
ICCP data
Estimated
Existing ICCP
Default PF (CIM, ALDR) ?
Confirmation
6
Power Factor Requirements –ERCOT
§3.15.1 ERCOT Responsibilities Related to Voltage Support
(4) For any Market Participant’s failure to meet the Reactive Power voltage control requirements
of these Protocols, ERCOT shall notify the Market Participant in writing of such failure and, upon
a request from the Market Participant, explain whether and why the failure must be corrected.
(6)
Annually, ERCOT shall review Distribution Service Provider (DSP) power factors using the
actual summer Load and power factor information included in the annual Load data request to
assess whether DSPs comply with the requirements of this subsection. At times selected by
ERCOT, ERCOT shall require manual power factor measurement at substations and POIs that
do not have power factor metering. ERCOT shall try to provide DSPs sufficient notice to perform
the manual measurements. ERCOT may not request more than four measurements per calendar
year for each DSP substation or POI where power factor measurements are not available.
(7) If actual conditions indicate probable non-compliance of TSPs and DSPs with the
requirements to provide voltage support, ERCOT shall require power factor measurements at the
time of its choice while providing sufficient notice to perform the measurements.
(8) ERCOT shall investigate claims of TSP and DSP alleged non-compliance with Voltage
Support requirements. The ERCOT investigator shall advise ERCOT and TSP planning and
operating staffs of the results of such investigations.
7
Power Factor Requirements –DSP & PUN §3.15.2
Or at their option, may meet alternative requirements specifically approved by ERCOT
a) PF > .97(lagging) for Max Net Active (MW)
Low side of .97
Unless Tariff says it is not a requirement
b) Load >10 MW require Watt/VAR metering
Za ≠ Zb
c)
d)
ALDR
High Side
Confirmation
ALDR
See a) & c)
8
NERC Power Factor Requirements
Version 0 Standards found lacking
The Commission believes that Reliability Standard VAR-001-1 is an appropriate place
for the ERO to take steps to address these concerns by setting out requirements for
transmission owners and LSEs to maintain an appropriate power factor range at their
interface. We direct the ERO to develop appropriate modifications to this Reliability
Standard to address the power factor range at the interface between LSEs and the BulkPower System.
VAR-001-3 (R5) Addressed the Directive:
R5. Each Purchasing-Selling Entity and Load Serving Entity shall arrange for (selfprovide or purchase) reactive resources – which may include, but is not limited to,
reactive generation scheduling; transmission line and reactive resource switching;, and
controllable load– to satisfy its reactive requirements identified by its Transmission
Service Provider.
9
NERC VAR -001-3 Current Language
R5. Each Purchasing-Selling Entity and Load Serving Entity shall arrange for
(self-provide or purchase) reactive resources – which may include, but is not
limited to, reactive generation scheduling; transmission line and reactive resource
switching;, and controllable load– to satisfy its reactive requirements identified by
its Transmission Service Provider.
(Retirement approved by FERC effective January 21, 2014.)
VAR-001-4 Standard is not approved and It will not address the power factor when
finalized
NERC indicates this standard wa retired as part of the Paragraph 81 Project
The Redundancy (FERC, below) may also reference OATT
PER FERC:
‘Retired …………, and VAR-001-2, Requirement R5 because those requirements were
found redundant with other requirements’ – Federal Register V78. #235 (12/6/13)
10
Low Power Factors in Load Flow and Load Flow
approximations
As Power Factors become more Lagging,
Circulating Currents Increase
Power Consumed by load Increases
System Efficiency Decreases
Lines with higher current carrying capacity are Required
More Generation is Required
Available Transfer Capacity Decreases
Loads with Significantly lagging Power Factors
attribute Reduced Available Transfer Capability into
load pockets and other constrained flowgates, and
may lead to Voltage Instability and Voltage Collapse.
This is a problem under peak conditions
11