If underfrequency generator protection is set at 58.3 Hz, what should the setpoint for load shedding be to maintain system stability?

To maintain system stability when underfrequency generator protection is set at 58.3 Hz, the load shedding setpoint should be configured to a higher frequency than 58.3 Hz but still within a range that allows for effective response to frequency drops. Setting the load shedding at 58.5 Hz serves this purpose as it provides a buffer above the generator protection threshold. This ensures that load shedding occurs before the system frequency drops to a level that could cause more severe issues, such as generator desynchronization or system collapse.

Choosing a setpoint below 58.3 Hz, like in the first option, would not provide the necessary protection and could lead to a failure to shed load in a timely manner as the frequency crisis develops. Setting it to 58.2 Hz, while higher than an immediate response threshold, is unnecessarily close to the protection setting and does not adequately cover for frequency fluctuations. Setting it at 59.8 Hz would provide insufficient reaction time, potentially allowing frequency to drop too low before load shedding occurs, thus jeopardizing system stability.

In this context, setting the load shedding at 58.5 Hz balances the need to act quickly while ensuring that the system remains stable, effectively preventing a cascade of failures in the power grid