Reliability Subcommittee Report Vishal C. Patel (RS Chair) PCC Meeting La Jolla, CA- March 22, 2015 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

Agenda Approval Item: – BES Inclusion Guideline Informational Items: – RAWG Update – BES Exception Processes – WECC-0100 Update 2 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

Approval Item: BES Inclusion Guideline RS sought approval of its’ proposed changes to the existing BES Inclusion Guideline at the July 2015 PCC meeting – PCC requested RS to re-evaluate proposed changes and take into consideration further comments based on the discussion RS received comments and has developed a proposal which has been sent out for review and is presented here for approval – RS has incorporated all of the comments/clarifications to the best of its’ ability while adhering to the intent of the guideline. Latest version has been posted for PCC review – Approval Item: Approve the document titled: BES Inclusion Guideline, dated February 16, W ESTERN E LECTRICITY C OORDINATING C OUNCIL

RAWG Update RAWG continues to work on activities related to the following issues: – Power Supply Assessment – Long Term Reliability Assessment – NERC Transmission Availability Data System Data Access for committee members at a granular level is no longer available due to the transition to NERC’s hosting of TADS (formerly TRD) 4 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

BES Exception Processes Planning Coordination Committee Informational Item

BES Exceptions Some of the comments on the Inclusion Guideline are regarding NERC BES Exception process. – RS held a robust discussion about issues the industry is facing and is presenting some initial thoughts here for informational purposes 6 W ESTERN E LECTRICITY C OORDINATING C OUNCIL Bulk Electric System (“BES”) Inclusion and Exclusions – NERC Self Determined process – NERC Exceptions process FERC distribution designation – Uses the “Seven Factor Test” Processes available for BES Exclusions

Processes 7 BES Definition Self determined Inclusion/Exclusion Meets the “bright line” definition BES Definition Self determined Inclusion/Exclusion Meets the “bright line” definition Exceptions Request Does not quite meet the “bright line” BES definition Can be used to add and remove BES designation Exceptions Request Does not quite meet the “bright line” BES definition Can be used to add and remove BES designation FERC Petition to Exclude distribution elements based on the application of the “Seven Factor Test” FERC Petition to Exclude distribution elements based on the application of the “Seven Factor Test” NERCFERC

Need Clarify ambiguity in the NERC BES Exception Request Evaluation Guideline – Ultimately a NERC level effort to address “Consistency” and “Transparency”

Example BES Exception Request Evaluation Guideline - Page A network that may transfer energy originating outside the local network for delivery through the local network under specific circumstances characterized by one or more of the following: – The amount of energy transferred is limited – The duration of the transfer is limited – The circumstances under which the transfer may occur is limited A network that does not meet the bright line threshold in Exclusion E3 because it may transfer power in parallel with the BES will be considered for exclusion based on the general and specific considerations for networks.

Options 1.Initiate a guideline document to clarify NERC’s Exceptions Request Guidance document – Approach NERC committee/subcommittee/task force. 2.Create Standards Authorization Requests (SARs) to clarify BES exceptions (available to WECC/PCC if desired). 3.Do nothing – BES/distribution issues decided at FERC – Compliance Jurisdiction

Project WECC-0100 Update Planning Coordination Committee March 2016

R1.1 Steady State Voltage Applicability – All applicable BES buses. Criterion: – At all applicable BES buses – 95% to 105% of nominal for P0 event, – 90 to 110% of nominal for P1-P7 events Discussion – Steady state voltage range for P0 event originates in ANSI C84.1 standard. No difference for 500 kV for simplification. – Wider range for P1-P7 events to allow for contingencies. – Discussed definition of nominal. TP/PC can define nominal in their individual criteria applicable to voltage limits in their system.

R1.2 Post-Contingency Voltage Deviation Applicability - At each applicable BES bus serving load. Criterion: – Post-Contingency steady-state voltage deviation at each applicable BES bus serving load shall not exceed 8% for P1 events Discussion – The 8% for P1 events is based on some entities indicating a state regulatory need, and some entities allowing 8% voltage deviation for shunt reactive power device switching after an outage. Main concern is deviation for low voltage. – For P2-P7 events it was concluded it would be acceptable to not have voltage deviation criteria that is more stringent than just having the steady state voltage range in requirement R1.1.

R Transient Voltage Performance Applicability - At each applicable BES bus serving load. Concerned with busses either feeding load directly or busses feeding lower voltage system that serves load. Applies to P1-P7 events R1.3 – V recovery 80% following fault. Within 20 seconds to account for FIDVR events. R1.4 – Following V recovery above 80%, Vdip below 70% for 30 cycles, 80% for 2 seconds. Developed White Paper with posting 3. R1.5 – Same performance as R1.4 for contingencies without a fault (event P2.1). R1.6 – Oscillations required to show positive damping within 30 seconds.

Impacts to Other Systems WR2. – If an entity uses more stringent Criteria than WR1 shall apply that Criteria only to their own system unless otherwise agreed upon by all Planning entities involved. WR3 – If an entity uses less stringent Criteria than WR1 shall allow others to have same impact to that part of system. These requirements carry over from the previous Criteria requirement WR2 which allowed systems to apply different requirements than Table W-1. Retains the philosophy of “allowable effects on other systems”.

WR4. Cascading and Uncontrolled Islanding Threshold Criteria to identify potential for Cascading or uncontrolled islanding. Criterion: – Post contingency analysis results in steady-state facility loading either exceeding 125% or the known trip setting. – Transient stability voltage recovery to above 80% longer than 20 seconds. – When unrestrained successive load loss or generation loss occurs. Discussion – Since Cascading or uncontrolled islanding would manifest itself differently in different parts of the system, a threshold criteria developed where further investigation would be warranted. – For unrestrained successive load or generation loss, it is anticipated this would be an iterative study process as determined by the entity.

WR5 Voltage Stability Positive reactive power margin for the following: – For transfer paths 105% or 102.5% of path flow for P0-P1 or P2-P7 events respectively. – For load areas 105% or 102.5% of forecasted peak load for P0-P1 or P2- P7 events respectively. Discussions – Did not find good technical justification to changing existing real power margins used in previous Criteria. – Path or load area assumed to be voltage stable by at least demonstrating the margins specified. Discussion this is a criteria for transmission Planning over the Planning Horizon, not a methodology to find system voltage stability limits beyond what the system is planned for.

WR6 Make Criteria Available Entity that uses study criteria different from criteria in WR1 shall make their criteria available upon request within 30 days.

Frequency Dip Criteria Frequency dip criteria is not included in this Criteria. A frequency dip criteria was included in Table W1 which was retired. There is no good technical justification for frequency dip impact to load. Under frequency concern is to protect generators. UFLS designed in coordinated fashion based on frequency excursion to prevent excessive gen loss, not based on frequency dip as defined by previous criteria. PRC-006 Automatic UF Load Shedding defines requirements for PC’s developing UFLS Programs, WECC Off Nominal Frequency Requirements. Generator frequency capability requirements defined in NERC PRC-024

Next Steps Posting 5 resulted in no substantive changes. Ballot Pool open 3/21 - 4/8 Standards Briefing 4/8 Ballot open 4/12 - 4/28 Next Board meeting June 2016

Vishal C. Patel, RS Chair Questions?