WECC Criterion – TPL-000-WECC-CRT-3Page 1 of 17
Criterion Development Timeline
This section is maintained by the drafting team during the development of the document and will be removed when the document is approved by the WECC Board of Directors (Board).
Description of Current Draft
Current Status
This is the second posting for comment of WECC Criterion TPL-001-WECC-CRT-3, Transmission System Planning Performance.
Document Scope
This document is designed to address the substance of TPL-001-WECC-CRT-2.1 (TPL), Requirement WR3 and the requirements imposed by NERC TPL-001-4, Requirements R5 and R6. Standard Authorization Request (SAR) WECC-0100 also provides for review and disposition of Table W-1 associated with the WECC TPL. Once the Requirements of this document are more fully developed the drafting team will revisit the need to edit, modify, or delete the table.
Criterion as Proposed
This document is designed to facilitate coordinated transmission planning for the Western Interconnection, and to facilitate the exchange of the associated planning information for normal and abnormal conditions. This document applies to studies conducted in both the near-term and the long-term planning horizons.
Applicability
- Planning Coordinator
- Transmission Planner
Facilities
The document applies to:
- Bulk Electric System (BES) substation buses with specified exclusions.
- Studies conducted in both the near-term and the long-term planning horizons.
- This document applies to all transmission planning studies conducted at the Western Interconnection level.
- Bulk-Electric System (BES) substations buses.
- Each of the following elements is specifically excluded from this Criterion:
- Line side series capacitor buses
- Line side series reactor buses
- Shunt capacitor buses
- Shunt reactor buses
- Metering, fictitious, or other points of interconnection modeled solely for measuring electrical quantities; and,
- Other buses specifically excluded by each Planning Coordinator or Transmission Planner internal to their system.
Effective Date
An Effective Date for the proposed document is targeted for January 1, 2016, to coincide with the Effective Date of NERC Standard TPL-001-4, Transmission System Planning Performance Requirements.
Requirements and Measures
As stated.
Compliance
WECC Criteria do not have a Compliance section.
Procedural Background
On September 5, 2012, the WECC Board of Directors (Board) adopted a recommendation by the Regional Criteria Work Group (RCWG) changing the designation of this document from a WECC Criterion (CRT) to a WECC Regional Business Practice (RBP). On June 24, 2014, the Board reversed that decision and designated this document as a CRT.
In further keeping with the September 5, 2012 recommendation, on November 28, 2012, a Standard Authorization Request (SAR) was submitted to evaluate whether this document should be drafted as a WECC Regional Reliability Standard (RRS).
On December 19, 2012, the WECC Standards Committee (WSC) accepted the SAR as drafted with specific approval to assign an evaluation team to review the subject matter and return a recommendation to the WSC as to whether the document should be redrafted as an RRS.
On June 26, 2013, the WSC approved the evaluation team’s recommendation to ballot the retirement of TPL-001-WECC-RBP-2.1, WR1, WR2, WR4 and WR5. If approved the retirement would become effective coincident with the Effective Date of NERC’s TPL-001-4, because the content of the WECC Requirements will be resident in the NERC TPL-001-4.
On August 8, 2013, the WSC assigned the original drafting team, augmenting the team during later weeks.
On October 8, 2013, a WECC Ballot Pool voted to retire TPL-(012 through 014)-WECC-RBP-2.1, WR1, WR2, WR4 and WR5 of the Effective Date of NERC TPL-001-4. (The Effective Date is projected for approximately January 1, 2016. It should be noted that the TPL has a staggered Effective Date.)
On November 1, 2013, the WECC-0100 Drafting Team (DT):
- Reported completion of the tasks assigned in the WECC-0100 Standard Authorization Request (SAR);
- Requested the WECC Standards Committee (WSC) deem the WECC-0100 SAR complete; and,
- Requested the WSC accept the DT’s recommendation to proceed with informal drafting in support of an iterative SAR tailored to the remedial needs of TPL-001-WECC-RBP-2.1, System Performance, WR3 as well as a more granular implementation plan of TPL-001-4, Transmission System Planning Performance Requirements Requirement R5 and R6.
In light of the retirement of the TPL-001-WECC-RBP-2’s Requirements WR1, WR2, WR4 and WR5, the drafting team reported that an update of the associated Table W-1 was underway by the Reliability Subcommittee.
The WSC agreed to expand the WECC-0100 drafting team to include the entire Reliability Subcommittee, and accept the drafting team’s recommendation that further drafting continue on remedial language for:
- TPL-001-WECC-RBP-2.1. WR3;
- Table W-1; and,
- TPL-001-4, Requirements R5 and R6.
On December 5, 2013, the Board approved the decision to retire portions of the WECC TPL upon the Effective Date of the NERC TPL.
During June 2014, the Planning Coordinating Committee (PCC) conducted a straw poll concluding the most appropriate document categorization for this document should be that of a WECC Regional Criterion.
On June 24, 2014, the Board changed the designation of this document from that of a RBP to that of CRT.
Completed Actions / Date- SAR Filed.
- Review Team files Preliminary Recommendation.
- WSC approves ballot to retire WR1, WR2, WR4 and WR5.
- Notice of Joint Session to discuss retirement.
- Ballot Pool open asking for retirement of WR1, WR2, WR4 and WR5.
- WSC approves Drafting Team.
- Ballot Pool closed asking for retirement of WR1, WR2, WR4 and WR5.
- Joint Session to discuss retirement.
- Ballot open asking for retirement of WR1, WR2, WR4 and WR5.
- Drafting Team – First Meeting – Orientation.
- Ballot closed asking for retirement of WR1, WR2, WR4 and WR5. Retirement approved.
- Version 1 Posted – Open 45-Day Comment Period.
- Version 1 Posted – Closed.
14.Version 2 Posted – Open 30-Day Comment Period / February 4, 2015
15.Version 2 Posted – Closed / March 6, 2015
16. Version 2 Responses to Comments posted / March 17, 2015
Anticipated Actions / Date
- Version 3 Posted – Open 30-Day Comment Period
- Version 3 Posted – Closed
- DT meets for final Comments / Forward to WSC
- WSC Meets
- Open Ballot Pool
- Joint Session – Notice
- Close Ballot Pool
- Joint Session
- Open Ballot
- Ballot Closed
- WSC Meets
- Notice to WECC Board of Directors
- Board
Implementation Plan
To Be Announced.
New or Modified Term(s) Used in the WECC Glossary for WECC Criteria and Naming Conventions (WECC Glossary).
This section includes all new or modified terms used in the proposed criterion that will be included in the WECC Glossary upon applicable approval. The new or revised terms listed below will be presented for approval with the proposed document. Upon WECC Board of Director (Board) adoption, this section will be removed and the approved terms will be moved to the WECC Glossary.
Term(s): None proposed
NOTE: When this document receives Board approval, the rationale boxes will be moved to the Supplemental Material Section of the standard.
A.Introduction
1.Title:Transmission System Planning Performance
2.Number:TPL-001-WECC-CRT-3
3.Purpose:To facilitate coordinated transmission planning for the Western Interconnection, and to facilitate the exchange of the associated planning information for normal and abnormal conditions.
4.Applicability:
4.1.Functional Entities:
4.1.1.Planning Coordinator
4.1.2.Transmission Planner
4.2.Facilities:
4.2.1.This document applies to studies conducted in both the near-term and the long-term planning horizons.
4.2.2.This document applies only to Bulk-Electric System (BES) substations buses.
4.2.3.This document applies to all transmission planning studies conducted at the Western Interconnection level.
4.2.4.Each of the following elements is specifically excluded from this Criterion:
4.2.4.1.Line side series capacitor buses
4.2.4.2.Line side series reactor buses
4.2.4.3.Shunt capacitor buses
4.2.4.4.Shunt reactor buses
4.2.4.5.Metering, fictitious, or other points of interconnection modeled solely for measuring electrical quantities; and,
4.2.4.6.Other buses specifically excluded by each Planning Coordinator or Transmission Planner internal to their system.
5.Effective Date:The Effective Date is the later of January 1, 2016 or the Effective Date of TPL-001-4, Transmission System Planning Performance, Requirements R2-R6 and R8.
6.Background:
(Optional)
B.Requirements and Measures
Rationale for Requirement WR1:Requirement WR1 recognizes that each system has its own unique characteristics that need to be addressed. Rather than lock each entity to a specific study parameter this Requirement sets a base study parameter coupled with a unique nominal value, established by the Transmission Planner and the Planning Coordinator, to be used in the absence of either a more stringent or less stringent study parameter.
In the context of this document the word “nominal” carries its common definition and could be, for example, either the base voltage or the operatingvoltage as established in the entity’s Planning Assessment. This voltage will vary from entity to entity.
Requirement WR1 does not preclude an entity from using either a more stringent or less stringent criteria. However, when an entity uses a study criteria other than that required in requirement WR1, it must make available its criteria upon request.
WR1.Each Transmission Planner and Planning Coordinator shall use the following base criteria in its Planning Assessment, unless otherwise specified in accordance with Requirements WR2 and WR3: [Addresses NERC TPL R5 and R6]
1.1.Steady-state voltages at all applicable Bulk-Electric System (BES) buses shall stay within each of the following limits:
1.1.195 percent to 105 percent of nominal for P0[1] event (system normal[s1]),
1.1.2 90 percent to 105 percent of nominal for P1-P7[2] events (post-contingency).
Rationale for Requirement WR1.2:Requirement WR1.2 establishes a target that could be met by each entity without incurring costs that would outweigh the benefits. Many legacy systems were not designed to meet a more stringent threshold. The eight percent target of Requirement WR1.2 is established not by a technical study; rather, it is established based on sound engineering judgment. Further, certain entities are bound by state tariffs that establish the percentage rate specifically at eight percent.
By default, only automatic post-contingency actions including capacity or reactor switching are considered when calculating voltage deviation. There is no low voltage requirement for P2-P7. There is no high voltage deviation for P1 through P7.
1.2.Post-Contingency steady-state low voltage deviation at each applicable BES bus serving load (having no intermediate connection) shall not exceed eight percent for P1 events. [Addressing TPL R5]
1.3.Transient stability voltage response at applicable BES buses serving load (having no intermediate connection) shall recover to 80 percent of pre-contingency voltage within 10 seconds of the initiating event for all P1-P7 category events.
1.4Following the initial recovery, subsequent voltage dips at each applicable BES bus serving load (having no intermediate buses) shall not remain below 60% for more than 1 second or below 70% for more than 5 seconds for all P1-P7 category events.
Rationale for Requirement WR1.4:For purposes of Requirement WR1.4, positive damping in stability analysis is demonstrated by showing that the amplitude of power angle or voltage magnitude oscillations after a minimum of 10 seconds is less than the initial post-contingency amplitude. In any case, results that do not show positive damping within a 30-second time frame shall be deemed undamped.
Requirement 1.4 is not intended to require that transient stability simulations be run out to 30-seconds all the time in order to ensure the system is stable and positively damped. Shorter runs are permissible.
1.4.Oscillations that do not show positive damping within a 30-second time frame shall be deemed unacceptable.
WM1. TBD
Rationale for Requirement WR2:Planning Assessment is a NERC defined term. For purposes of Requirement R2, the requirement applies to all planning studies applied at the Western Interconnection level.
The rationale for Requirement R2 is to ensure that planning entities do not impose more stringent requirements on systems other than their own. It may use more stringent criteria on its own system but may not impose more stringent criteria on others.
Planning entities may mutually agree to use study criteria that is more stringent than that described in this document.
WR2. Each TP and PC that uses more stringent criteria in its Planning Assessment than that stated in Requirement WR1 shall apply that criteria only to its own system, except where otherwise agreed upon by all planning entities included in the Planning Assessment.
WM2. TBA
Rationale for Requirement WR3:The rationale for requirement WR3 is to ensure that where study criteria different from that required in Requirement WR1 is used, the study criteria are made available to any entity in need of it. The intent of the requirement is not to mandate “how” that information is published or exchanged – only that it be made available. “How” the information is exchanged is business function left open to the affected entities.
WR3.Each Transmission Planner and Planning Coordinator that uses less stringent criteria in its Planning Assessment than that stated in Requirement WR1 shall allow other Transmission Planners and Planner Coordinators to have the same impact on that part of the system for the same category of planning events (e.g., P1, P2).
WM3. TBA
Rationale for Requirement WR4:Requirement WR4 is designed to establish precautionary markers that when discovered warrant investigation. The Requirement is not intended to implythat the presence of any one of more of the bulleted conditions creates a de facto negative impact on reliability.
The term “cascading” in Requirement WR4 is not used as the NERC defined term “Cascading.”
The specific amounts addressed in WR4, numbered section 3, have not been specified. The drafting team suggests that due to the breadth of the possible permutations, the amount should be left to the sound engineering judgment of the planning entity.
WR4. Each Transmission Planner and Planning Coordinator shall use the following indicators to identify the potential for cascading or uncontrolled islanding requiring further investigation:
(Option 1 – two bullets – numbering to be corrected)
1)When a contingency analysis results in post-contingency loading that is in excess of a known BES facility trip setting;
2)When a contingency analysis results in post-contingency loading of 125% of the highest applicable facility rating for the BES facility studied;
(Option 2 – one bullet – numbering to be corrected)
3)(Option 2) When a contingency analysis results in post-contingency loading in excess of a facility trip setting for the facility studied if known. If the facility trip setting is not known, when a contingency analysis results in 125% of the highest applicable facility rating.
4)Transient stability voltage response at any applicable BES bus outside of the criteria that is defined in Requirement WR1.3 of this document.
5)If successive load or generation loss occurs outside of the studied area that is not restrained.
6)(Do we need to address “sequentially spreading” outages, or cascading or….???)
WM4. TBD
Rationale for Requirement WR5:Requirement WR5 addresses “what” must be achieved and does not “how” to do it.
For a review of “how’ to achieve the goals, please refer to:
- “The WECC Voltage Stability Assessment Methodology”
- “WECC Guide to WECC/NERC Planning Standards I.D: Voltage Support and Reactive Power, Prepared by:Reactive Reserve Working Group (RRWG), Under the auspices ofTechnical Studies Subcommittee (TSS); Approved byTSS, March 30, 2006.
- Additional guidance is contained in Section 2.2 Voltage Stability of the Guide to WECC/NERC Planning Standards 1.D, Voltage Support and reactive Power, March 30, 2006.
Power flow solutions refer to post contingency conditions where the actions of reactive devices should be modeledfor the appropriate time frame being studied.
WR5.Each Transmission Planner and Planning Coordinator shall identify voltage stability bymaintaining positive reactive power margin at the real power flow defined through the following criteria:
5.1All P0-P1 eventsshall demonstrate a positive reactive power margin at a minimum of 105 percent of transfer path flow.
5.2All P0-P1 eventsshall demonstrate a positive reactive power margin at a minimum of 105 percent of forecasted peak load.
5.3All P2-P7 eventsshall demonstrate a positive reactive power margin at a minimum of 102.5 percent of transfer path flow.
5.4All P2-P7 eventsshall demonstrate a positive reactive power margin at a minimum of 102.5 percent of forecasted peak load.
WM5. TBD
Rationale for Requirement WR6:RELOCATE THIS IF NEEDED.Requirement WR6 ensures the free flow of information between entities.
WR6. Each Transmission Planner and Planning Coordinator that uses study criteria different from the base criteria in Requirement WR1 shall make its criteria available upon request.
WM6. TBA
Version History
Version / Date / Action / Change Tracking1 / March 6, 2008 / WECC Planning Coordination Committee (PCC) approved TPL-(001 thru 004)-WECC-1-CR. / Reliability Subcommittee translates existing WECC components of NERC/WECC Planning Standards into a CRT.
1 / April 16, 2008 / WECC Board of Directors (Board) approved / No substantive changes
2 / October 13, 2011 / PCC approves / Clarifies “corridor”
2 / December 1, 2011 / Board approves / No substantive change
2 / September 5, 2012 / Board approves / Approved a nomenclature change from “CRT” to “RBP”
2.1 / August 6, 2013 / Errata / WM2 Measure moved to WM3. WM3 Measure moved to WM4. WM4 Measure moved to WM2.
2.1 / December 5, 2013 / Board approves / On October 8, 2013, the Ballot Pool voted to retire WR1, WR2, WR4 and WR5 of TPL-(012 through 014)-WECC-RBP-2 as of the Effective Date of NERC TPL-001-4. On December 5, 2013, the Board ratified that decision.
2.1 / June 24, 2014 / Board changed the RBP designation to that of CRT / No substantive change, only designation.
3 / Pending
Disclaimer
WECC receives data used in its analyses from a wide variety of sources. WECC strives to source its data from reliable entities and undertakes reasonable efforts to validate the accuracy of the data used. WECC believes the data contained herein and used in its analyses is accurate and reliable. However, WECC disclaims any and all representations, guarantees, warranties, and liability for the information contained herein and any use thereof. Persons who use and rely on the information contained herein do so at their own risk.