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NOTICE DATE:  November 30, 2018
NOTICE TYPE:  W-D113018-0 Operations
SHORT DESCRIPTION:  2018 Winter and 2019 Spring Seasonal Voltage Profiles
INTENDED AUDIENCE:  Resource Entities (REs), Qualified Scheduling Entities (QSEs), Transmission Operators (TOs), Transmission Service Providers (TSPs), and NERC-registered Generator Operators (GOPs) and Transmission Operators (TOPs)
DAY AFFECTED:  December 1, 2018
LONG DESCRIPTION:  ERCOT has posted the 2018 Winter (December 1, 2018 - February 28, 2019) and 2019 Spring (March 1, 2019 - May 31, 2019) Voltage Profiles, which include Voltage Set Points for each Generation Resource's Point of Interconnection (POI).  ERCOT and the TSPs derived these Voltage Profiles after a series of joint studies and several meetings.  In accordance with NERC Reliability Standard VAR-001-4.2 R5, the posted spreadsheet lists seasonal Voltage Set Points for every Generation Resource at its POI in columns G and K, and V and Z. Voltage Set Points at the high side of the step-up transformer are listed in columns L and N, and AA and AC.
As required by ERCOT Nodal Protocols Section 6.5.7.7(5), each Generation Resource shall follow the Real-Time Voltage Set Point instruction given by ERCOT or the TSP. Any operator of one or more Generation Resources, including any NERC-registered GOP, whose Voltage Set Point in the posted Voltage Profile for each upcoming season differs from its Real-Time Voltage Set Point should coordinate with its TSP to determine if changes to the Real Time Voltage Set Point are needed.
In accordance with ERCOT Nodal Operating Guide Section 2.7.3.5(4), a Resource Entity required to provide Voltage Support Service (VSS), which includes any NERC-registered GOP, must maintain the generator voltage or Reactive Power schedule within 2% of the Voltage Set Point when operating at less than the maximum reactive capability of the Generation Resource, except under Force Majeure Events or unless explicitly authorized by or requested by ERCOT or the interconnecting Transmission Operator (TO).  When a Resource Entity is instructed to follow a new Voltage Set Point, ERCOT expects the Generation Resource to reposition its AVR to best follow the new Voltage Set Point even if the new Voltage Set Point is within 2% of the previous Voltage Set Point.
ERCOT reminds all Generation Resource operators that the response to a TO Voltage Set Pont instruction must be completed in no more than five minutes from receipt of the instruction, as per ERCOT Nodal Operating Guide Section 2.2.10(3)(b). Also, in accordance with ERCOT Nodal Protocols Section 3.15.3, each Generation Resource AVR must be operated in automatic voltage control mode and set to control the POI voltage to the Voltage Set Point.  In accordance with ERCOT Nodal Operating Guide Section 2.7.3.5 (3), an RE shall notify its QSE as soon as practicable if its Generation Resource cannot operate within 2% of the Voltage Set Point.  In accordance with ERCOT Nodal Operating Guide Section 2.7.3.4 Qualified Scheduling Entity Responsibilities, the QSE shall notify ERCOT as soon as practicable if its Generation Resource is unable to operate within 2% of the Voltage Set Point.
ADDITIONAL INFORMATION:   The 2018 Winter and 2019 Spring Seasonal Voltage Profiles can be found on the ERCOT Market Information System (MIS) under Voltage Profiles<https://mis.ercot.com/pps/tibco/mis/Pages/Grid+Information/Transmission> on the Grid/Transmission page under Voltage and Dynamic Ratings.  The Seasonal Voltage Profile Studies for Winter and Spring 2019 may be accessed on the Groups and Rules/Transmission Service Provider Information page on the MIS.  A Digital Certificate is required to access the MIS.
CONTACT:  If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask]<mailto:[log in to unmask]>.


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