This Nodal Protocol Revision Request (NPRR) changes the Low Dispatch Limit (LDL) calculation to ensure that the LDL and High Dispatch Limit (HDL) limit sent to the Security Constrained Economic Dispatch (SCED) do not exceed the High Sustained Limit (HSL) under any circumstance.
Reason:
When the output MW of a Resource exceeds its telemetered HSL for a short time (e.g. governor response) SCED will attempt to dispatch the Resource above its HSL. Modifying the LDL calculation with a final check will ensure that the LDL and HDL limits calculated by the Resource Limit Calculator (RLC) and sent to SCED do not exceed the HSL under any circumstance.