schemes, automatic load restoration schemes, automatic capacitor/reactor switching, and Remedial Action Scheme (RAS). All UFLS data will be documented in the annual Stability Book. Under Voltage Load Shedding Relay Data An TSP which has UVLS relays in its service area designed to mitigate under voltage conditions potentially impacting the system reliability is to establish and maintain a UVLS Program consistent with NERC Standards. The TSP owning an UVLS Program will submit the corresponding relay model to ERCOT during the annual data update. The DWG member shall submit the UVLS relay data in the form of a PSSE dyre file using an appropriate model. It is the responsibility of the TSP to ensure the UVLS program model submitted has been tested through an assessment as per NERC standards. Also, the TSP shall indicate any other schemes that are part of or impact the UVLS programs such as related generation protection, islanding schemes, automatic load restoration schemes, automatic capacitor/reactor switching, and RASs. The shall contain the necessary information to properly represent the under voltage relay actions in a dynamic study, including: Location (bus number and/or load ID) of load to be interrupted. Fraction of load to be interrupted. Corresponding voltage set points. Overall scheme clearing (including all time delays, breaker clearing times, etc.). All UVLS data from the responsible entities will be documented in the annual Stability Book. Protective Data The operation of protection, control, and RAS systems can affect the dynamic performance of the ERCOT system during and following contingencies. Planning, documenting, maintaining, or other activities associated with these systems is outside the scope of the DWG. However, because they can affect dynamic performance, the DWG should, on an as needed basis, identify and document protection, control, and RAS systems for inclusion to its dynamic data sets. Identification of
schemes, automatic load restoration schemes, automatic capacitor/reactor switching, and Remedial Action Scheme (RAS). All UFLS data will be documented in the annual Stability Book. Under Voltage Load Shedding Relay Data An TSP which has UVLS relays in its service area designed to mitigate under voltage conditions potentially impacting the system reliability is to establish and maintain a UVLS Program consistent with NERC Standards. The TSP owning an UVLS Program will submit the corresponding relay model to ERCOT during the annual data update. The DWG member shall submit the UVLS relay data in the form of a PSSE dyre file using an appropriate model. It is the responsibility of the TSP to ensure the UVLS program model submitted has been tested through an assessment as per NERC standards. Also, the TSP shall indicate any other schemes that are part of or impact the UVLS programs such as related generation protection, islanding schemes, automatic load restoration schemes, automatic capacitor/reactor switching, and RASs. The shall contain the necessary information to properly represent the under voltage relay actions in a dynamic study, including: Location (bus number and/or load ID) of load to be interrupted. Fraction of load to be interrupted. Corresponding voltage set points. Overall scheme clearing (including all time delays, breaker clearing times, etc.). All UVLS data from the responsible entities will be documented in the annual Stability Book. Protective Data The operation of protection, control, and RAS systems can affect the dynamic performance of the ERCOT system during and following contingencies. Planning, documenting, maintaining, or other activities associated with these systems is outside the scope of the DWG. However, because they can affect dynamic performance, the DWG should, on an as needed basis, identify and document protection, control, and RAS systems for inclusion to its dynamic data sets. Identification of
DWG_Procedure_Manual_Revision_12_ROS_Approved_01-11-18.docx