Study on the balancing authority ACE limit standard of North American power grid

Abstract

The control performance standard 2 (CPS2), once adopted in North American power grid, has some disadvantages, such as having insufficient evaluation time and ignoring the correlations between area control errors (ACEs). It was not suitable to restrain the tie‐line power flow and had been replaced by the balancing authority ACE limit (BAAL) standard. It is found that the design mechanism of BAAL standard is derived from reliability requirement. Its purpose is to restrict the duration of over‐limit frequency to be less than 30 min by managing the fluctuation of each ACE. The role of the new standard in co‐operation with control performance standard 1 (CPS1) is analyzed, and some of its technical characteristics, including short‐time operation security, setting dynamic ACE limit, and permitting the correlations between ACEs, are discussed. The simulation results indicate that even in the case where each area performance meets the requirements of CPS1 and CPS2, the short‐time frequency performance still cannot meet the requirement of operation security. BAAL standard co‐operating with CPS1 can not only restrict the standard deviation of frequency fluctuation over a long term but also maintain the short‐time frequency quality, which is beneficial for real‐time operation security and reliability. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.