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Lessons Learned from AIE Surveys Performed in Summer 1999. SERC System Operators Conference Spring - 2000. 1999 AIE Surveys. What is an AIE Survey? When are AIE Surveys performed? What lessons were learned from the AIE Surveys?. 1999 AIE Surveys. What is an AIE Survey?
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Lessons Learned fromAIE Surveys Performed in Summer 1999 SERC System Operators Conference Spring - 2000
1999 AIE Surveys • What is an AIE Survey? • When are AIE Surveys performed? • What lessons were learned from the AIE Surveys?
1999 AIE Surveys • What is an AIE Survey? • When are AIE Surveys performed? • What lessons were learned from the AIE Surveys?
AIE Survey • An AIE survey is a means of identifying control areas that operate with prolonged generation/load imbalance. • All control areas within an Interconnection must participate in AIE surveys.
1999 AIE Surveys • What is an AIE Survey? • When are AIE Surveys performed? • What lessons were learned from the AIE Surveys?
Calling AIE Surveys • AIE Surveys are called by the Chairman of the Performance Subcommittee • Performance Subcommittee established informal criteria for calling AIE Surveys if the daily Epsilon 1 (an indication of frequency error) is greater than 16.0 milliHertz
1999 AIE Surveys • What is an AIE Survey? • When are AIE Surveys performed? • What lessons were learned from the AIE Surveys?
Bad Performers Discussed in presentation.
ECARJudgementof Cinergy • … CINergy used the Eastern Interconnection as a supplemental resource without regard to the reliability or integrity of the system or the well being of the many users of the system. • … CINergy’s interchange performance on July 22, 23, and 29 was the major contributor to the low frequency experienced in the Eastern Interconnection • CINergy’s blatant disregard for NERC policy and ECAR documents during this period jeopardized the reliability of the Eastern Interconnection especially in its ability to respond to additional contingencies. • .… A follow-on ECAR investigation … led the ECAR Executive Board to conclude that CINergy knowingly disregarded the clearly defined operating requirements of NERC Policy 5 and ECAR Documents 2 and 3 during the AIE survey period.
Entergy July 22, 1999 • System Load was higher then expected • Unit Outages : • Baxter Wilson 1(515 MW), • Sterlington 6 (225 MW), • Lake Catherine 2 (30 MW) • Several Units were derated • Approximately 250 MW of purchased capacity recalled • Corrective Actions Taken : • Curtailment of curtailable industrial customers • Curtailment of capacity sales • bought emergency power
Entergy July 23, 1999 • Unit Outages : • Baxter Wilson 1 (515 MW) • White Bluff 1 (815 MW), • Willow Glenn 5 (550 MW) • 500 MW derated generating capacity • Transaction Information : • Lost 500 MW of SPP Emergency Assist • Lost 400 MW of pre-scheduled purchase power • Hourly purchase power availability was minimal • Corrective Actions Taken : • curtailed all Interruptible/Curtailable Retail load • curtailed 900 MW of firm load at 2:42 PM.
Entergy Conclusions • “If we had to do it again, we wouldn’t.” -Tim Ponseti • Lessons Learned : • Timing is critical • Call for emergency assistence • Call for curtailable load • Additional generation has been taken out of mothballs to provide additional generation
TVA • July 29 - TVA experienced a telemetry failure on one phase of a 500 kV transmission line • This caused an offset of 300+ MW in real time ACE used for control • The failure was not detected and/or corrected during the AIE Survey period
Lessons Learned formTie Line Metering Error • Sudden spikes of ACE are not always false- telemetry • All tie line meters need voltage alarms - phase to phase • Finding erroneous errors are very difficult without hard copy charts • All tie line meters should have reasonability alarms • All control areas should have at minimum trend charts for net schedules and actuals