To approve NPRR178 as recommended by TAC in the 8/6/09 TAC Recommendation Report
Passed
Background
Status:
Approved
Date Posted:
May 26, 2009
Sponsor:
ERCOT
Urgent:
No
Sections:
6.5.7.6.1
Description:
The purpose of this Nodal Protocol Revision Request (NPRR) is to bring the Nodal Protocols in line with the nodal program implementation:
* Changes to the regulation reduction calculation to account for movements in generation due to units getting updated Base Points from Load Frequency Control (LFC).
* The other change is regarding the Regulation Up (Reg-Up)/Regulation Down (Reg-Down) allocation to Qualified Scheduling Entities (QSEs) to take out the constraint for each four-second interval, since the full amount of Reg-Up/Reg-Down responsibility is realizable in five-minutes and compliance is also on a five-minute basis.
Reason:
By utilizing the movement of other units toward their Base Points, it is expected that this will result in improved frequency control and better operation.
The regulation requests for each control cycle of each QSE are limited to 125% of the total amount of Regulation Service in ERCOT divided by the number of control cycles in five minutes. Since the full amount of Reg-Up/Reg-Down responsibility is realizable in five-minutes and compliance is also on a five-minute basis, there is no explicit need to constrain the QSE regulation requests in each control cycle.