Comment Report Form for WECC-01001
Posting #5
The WECC-0100, TPL-001-WECC-CRT-3, System Performance Drafting Team (DT) thanks everyone who submitted comments on the proposed documents.
Posting
This document was last posted for a 30-day public comment period fromDecember 18, 2015 through January 18, 2016.
WECC distributed the notice for the posting onDecember 18, 2015. The DT asked stakeholders to provide feedback on the proposed document through a standardized electronic template. WECC received comments from two companies representing four of the eight Industry Segments, as shown in the following table.
Location of Comments
All comments received on the document can currently be viewed in their original format on the project page under the “Submit and Review Comments” accordion.
Changes in Response to Comment
After review and consideration of all comments received the drafting team opted to make no further changes to the document.
Effective Date
The proposed 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, subject to required approvals.
Justification
The effective date is targeted to coincide with the effective date of TPL-001-4, Transmission System Planning Performance.
Consideration of Early Compliance
The DT foresees no reliability-related issues if an entity chooses to implement the document early; however, entities should continue to adhere to approved WECC Criteria until they are retired.
Retirements
This document will replace TPL-001-WECC-CRT-“2” that is to be retired as of the Effective Date of this project.
Action Plan
On February 11, 2016, the DT agreed by consensus of those DT members present to forward the project to the WECC Standards Committee (WSC) with a request for ballot and disposition. The WSC is scheduled to meet on March 8, 2016.
Documents for review are located at the WECC-0100 Project Page on the Posted for Comment accordion.
Contacts and Appeals
If you feel your comment has been omitted or overlooked, please contact the Manager, WECC Standards Processes, W. Shannon Black, at . In addition, there is a WECC Reliability Standards Appeals Process.
The WECC Standards Voting Sectors are:
1 — Transmission Sector
2 — Generation Sector
3 — Marketers and Brokers Sector
4 — Distribution Sector
5 — System Coordination Sector
6 — End Use Representative Sector
7 — State and Provincial Representatives Sector
8 — Other Non-Registered WECC Members and Participating Stakeholders Sector
Sector1 / 2 / 3 / 4 / 5 / 6 / 7 / 8
1 / Jeff Watkins / NV Energy / X / X / X / X
2 / Rikin Shah / PacifiCorp / X / X / X / X
Index to Questions, Comments, and Responses
Question
- The Drafting Team welcomes comments on all aspects of the document.
Summary Consideration: / Changes to the document along with an action plan are provided in the Summary section of this document’s preamble.
Commenter / Yes / No / Comment
NV Energy / NV Energy has the following questions/comments:
WR1 1.1.2:
This requirement applies to both single and multiple contingencies. The main point of maintaining .90 pu voltage is to provide acceptable voltage to loads on the system. Has there been any thought to applying this criteria to P0-P7 contingencies only where non-consequential load loss is not allowed?
In the contingency scenarios where non-consequential load loss is allowed, other schemes would trip load such as Under Voltage Load Shedding. Does it really make sense to apply these criteria to contingency situations where non-consequential load loss is allowed when the main point of the .90 pu minimum voltage is specified to keep non-consequential load online?
WR1 1.2
The above post-contingency steady-state voltage criteria (deviation shall not exceed 8%) applies to each applicable BES bus serving load. When conducting transmission planning studies to evaluate meeting the criteria, automatic devices such as voltage regulators are allowed to operate. For example, a 230/138 kV Load Tap Changing Transformer would be allowed to operate prior to measuring the voltage deviation. However, in the case of a 138/12 kV Load Tap Changing Transformer it appears that if the voltage deviation on the 138 kV buss were greater than 8%, it would be a violation of the proposed criteria even though the LTC would operate and bring the 12 kV voltage to within specification.
The requirements for WR1 1.2 should not apply in this situation.
WR1 1.3:
Understanding that this requirement is specific to Fault Induced Voltage Recovery, are system load models accurate enough to simulate this phenomenon? Could it be argued that after 3 or 4 seconds after an even in a transient run, that the system has reached a steady state level? What is the justification behind the 20 second criteria? Even after 10 seconds, a system should reach post-transient steady state voltages.
WR1 1.4:
Similar to the comments above regarding 1.1.2, does it make sense to apply the 1.4 criteria to all contingencies, including those that allow non-consequential load loss? The main point of the criteria specified after the voltage reaches 80% of pre-contingency voltage is to keep sensitive loads online after a fault occurs. For more severe contingencies, where non-consequential load loss is acceptable, does it make sense to apply this criteria? It seems that this criteria should only be applied to P1 – P7 contingencies where non-consequential load loss is not allowed.
For PSLF, the most commonly used tool for analyzing voltage and frequency is WCA. Currently, WCA has an option to specify the time to begin monitoring the voltage, but it does not have an option to specify when a voltage reaches a percentage of the pre-contingency voltage. Have any discussions been initiated with GE to provide this capability in upcoming versions of the PSLF software? If not, how will violations be identified with this new criteria?
WR1 1.1.2
Please see the Rationale box for WR1.2 that states: “For purposes of this document, a BES bus that is serving load is the bus with direct transformation from BES-level voltage to distribution-level voltage that serves load.” The language does not apply to all load buses in general; rather, it applies only to those Facilities determined in the Facilities section, and the acceptable voltage limits referenced in WR1. Parts 1.1.1 and 1.1.2. The reason for this approach is to maintain the integrity of the grid.
WR1.1.2.
In the described scenario, if the 138kv bus has a voltage deviation greater than 8%, that deviation could be allowed in the specific entity’s own criteria per WR3. Beyond a general description of the intent of the language, a DT is not in a position to advise on adherence.
WR1 1.3
The DT believes the question is covered in its white paper, WECC-0100 TPL-001-WECC-CRT-3 (CRT), Transmission System Planning Performance, Proposed Transient Voltage Response Rationale for CRT Requirements R1.3 and R1.4, July 24, 2015, as posted on the WECC-0100 project page on the Posted for Comment accordion. Recovery before 20 seconds would not result in a violation of the Fault Induced Delayed Voltage Recovery, criteria as drafted in WECC Requirement WR1.1.3 (see adherence qualifier above)
WR1 1.4:
The DT knows of no discussions with GE. It should be noted that adherence is required of a WECC Criterion. How adherence is determined is outside of the scope of the DT. The DT believes it makes sense to apply 1.4 criteria to all contingencies and not just the P1 through P7 contingencies where non-consequential load loss is not allowed. The goal is to maintain the integrity of the system and minimum non-consequential load loss in neighboring systems.
PacifiCorp / The TPL001-4 R5 requires each Transmission Planner (TP)and Planning Coordinator (PC) to have their own criteria for acceptable System performance with respect to voltage under different System conditions and R6 requires each TP and PC to document how they will analyze and identify System instability for conditions such as Cascading, voltage instability, or uncontrolled islanding. PacifiCorp's questions is related to the recommendation made by Planning Coordination Committee (PCC) at its October meeting which is:
Has the drafting team considered only to include criteria on the allowable effects on neighboring system (WR2 and WR3)in the proposed WECC criterion “WECC Criterion - TPL-001-4 WECC-CRT-3" and to move the steady state voltage limits and other transient stability response present in WR1 to a guideline document.
(1) Whether or not the above mentioned recommendation has been considered or not?
(2) What is the rationale not to implement this recommendation? Categorization?
Development of WECC Guidelines falls outside of the scope of the DT. Guidelines are created at the Standing Committee level. There is an ongoing dialogue with the PCC to ensure that information deleted from the Version 2 of this document can be addressed elsewhere.
The decision to categorize the project as a WECC Criterion and not a WECC Guideline was vetted at the PCC during the early stages of this project and a number of times thereafter. In each case, the majority opinion was to classify the project as a WECC Criterion. When the WECC Ballot Pool agreed to retire all but WR3 of Version 2 of the related document there was no prohibition against the PCC picking up the substance of the rest of Version 2 and addressing it as a WECC Guideline.
For more details, please see the Response to Comments, Posting 3, Western Area Power Administration, Issue 7.
“7. Guideline versus Category
The DT continues to be aware that a segment of the stakeholders would prefer categorization as a WECC Guideline and not a WECC Criterion. Although Western provides a sound argument for re-categorization the DT notes that the category assignment was vetted at the Planning Coordinating Committee (PCC) early in the drafting process and approved by the WECC Standards Committee. A straw poll taken at a regularly held PCC meeting indicated that the bulk of those in attendance believed the document should be categorized as a Criterion. The DT continues to stay active at the PCC keeping the PCC informed of its approach to meeting the scope of the Standard Authorization Request (SAR). The DT encourages all stakeholders to participate in the PCC forum in order to remain apprised on the DT’s efforts and also to provide input on possible substantive changes. “