Consideration of Comments on FRCC Standard for Regional Generator Performance During Frequency and Voltage Excursions (FRCC-S-PRC-024) Version 2

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1 1. In response to comments received, the Drafting Team has modified the Applicability section and now includes applicability of the standard to sites > 75 MVA (gross aggregate nameplate). Do you agree with this change? Alan Gale City of Tallahassee John Mulhausen Florida 2. Requirement 1 now requires islanding schemes to be compliant with the time durations specified in Appendix A. Do you agree? Alan Gale City of Tallahassee The requirement does not specify a pre-planned islanding scheme or any tripping by the transmission system protection. By including the words as written, I am afraid we have extended this standards applicability to the Transmission Owner or Operator. If the intent is to only prohibit "islanding" if the generator with it's own auxiliaries, that is not clear by the language provided. Additionally, the verbiage in the requirements should match the verbiage in Appendix A. (i.e. "No generator tripping or islanding" in the first column.) Page 1 of 6

2 In order to maintain clarity of responsibility and applicability along with promoting a clear understanding of the standard, the DT intentionally refers to the generator islanding concept specifically, within the standard. The intent of the DT, with this standard, has been to focus on Regional coordination of generator performance. Islanding Schemes are required to be addressed under NERC Reliability standard PRC (UFLS programs). The complementary FRCC UFLS standard being developed in parallel with this standard includes the requirement for coordination of other frequency activated switching in requirement R3 of that standard. The DT deliberated about your comment but concluded that the current applicability language improves clarity of the requirements, meets the technical intent of the standard, addresses the NERC Reliability standard requirements and adequately addresses the reliability implications of islanding in the context of both the generator owners and load serving entities. The DT team agrees with the addition of islanding being specifically included in the performance criteria in the first column of appendix A in order to match the language of Requirement R1. The standard has been revised accordingly. Reliant Energy John Simpson 3. Based on comments received, the Drafting Team has modified Risk Factors. Do you agree with the Risk Factors of this draft? City of Tallahassee Alan Gale Page 2 of 6

3 4. The Drafting Team has added Compliance elements of this standard to Section D of this draft. Do you agree with the elements of Section D, Compliance? City of Tallahassee Alan Gale My disagreement is with the Data Retention section 1.3. To require retention of documentation for the "service life of the generator" is unduly burdensome for the GO. Documentation retention that could be 30 years or longer is excessive. A more limited retention is warranted. I would recommend 3 years at the most. We should not be concerned if the generator met the requirements 5 years ago. We should be concerned that it meets the requirements right now! The DT agrees with your comment and has revised the standard to limit the data retention period to 3 (three) years to coincide with the current entity compliance monitoring audit cycle. Page 3 of 6

4 Reliant Energy John Simpson 5. In response to comments received, the Drafting Team made minor clarifications to Appendix A. Do you agree with these clarifications? Alan Gale City of Tallahassee DT agrees and has incorporated in current revision of the standard. A) See 2 above to make verbiage match requirements. B) Remove carriage return after "105%" and before "of rated". John Muhausen Florida The last requirement from Appendix A, Generator overexcited stator current (or generator apparent impedance) less than 150% of nameplate rating needs further clarification. The phrase or generator apparent impedance is intended to apply to backup phase distance relays but it is not specifically stated and could easily be misinterpreted. I propose splitting the requirement into two separate requirements: Page 4 of 6

5 1.Generator overexcited stator current less than 150% of nameplate rating current when applying generator phase overcurrent relays. 2.Generator MVA less than 150% of nameplate at rated power factor when applying generator backup phase distance relays. I would like to state that the SPCTF at NERC is likely to recommend a 200% setting based on IEEE Guidelines in a future SAR/Standard. If adopted FRCC will have to change to 200% since it is more stringent. An associated voltage requirement footnote still has to be associated with both of the split requirements. It should be selected for 90% to 110% terminal voltage. I have a concern with the second part of footnote 4 that states "without faulted conditions within the generator or GSU." This could be used in some way as an escape clause to set tripping elements within the specified FRCC "No Trip" ranges. The Standard does not state how this clause would actually be applied in the relay settings. This could lead to unintended consequences. Examples should be provided. The DT agrees with your comment and has incorporated 1 and 2 above into the revision to appendix A. The DT feels that the standard should continue to be developed in accordance with the historical settings that have been established within the FRCC. If the NERC standards are developed and eventually require a 200% setting the standard in-place at that time, can be revised to address this via the standards process. The DT discussed footnote 4 of appendix A and the consensus was that along with your suggested requirement Page 5 of 6

6 clarifications, the coordination requirements are now clear and well defined (as revised). Reliant believes there has been an incorrect modification made to the last box in Appendix A. The apparent impedance varies inversely to the stator current so we do not want to trip the generator if the stator current is less than 150% of nameplate or if the apparent impedance is GREATER than the equivalent apparent impedance at that current level. The language as written is confusing and seems to be opposite this last point. The DT agrees with your comment and has incorporated revisions to appendix A, to clarify the language used to convey the technical basis of the coordination requirement. 6. Do you have any other comments on Draft #2 of this standard? City of Tallahassee Alan Gale None None None Page 6 of 6