Assessing the Impact of Variable Generation on ROCOF Adequacy

Generating units are equipped with anti-islanding protections. Some of those protections schemes are based on detecting the excessive Rate of Change of Frequency that occurs when a generator becomes islanded and the power imbalance within the island is significant. A common concern within power system operations is the inertia reduction due to variable generation integration, which increases the naturally-occurring rate of change of frequency after sudden losses of generation (load). This work proposed a dynamic simulation approach to estimate the integration limit of variable generation in terms of its impact on inertia reduction and increase in rate of change of frequency. The RTS-96 test case is presented to obtain numerical results.