Impact study of a generation rich island and development of auto load shedding scheme to improve service reliability

Abnormal conditions in a power system create fluctuations to electrical quantities such as voltage, frequency and current. Some of them may lead to fall of system frequency and sometimes extreme abnormality leads to system blackout. Planned and proper islanding may protect the system from complete blackout even in case of extreme abnormalities. Islanding operation not only helps stabilizing a faulted system but also supports power supplies to critical and important loads, in extreme emergency. But the islanding systems are weaker than integrated system so the stability of islands is the prime concern when an integrated system is disintegrated. In this paper different impacts on a generation rich island have been studied and a frequency based auto load shedding scheme has been developed for sudden load addition, generation outage and combined effect of both to the island. The developed scheme has been applied to Dhaka Island (the largest and generation rich island of Bangladesh Power System) to validate the effectiveness of the developed technique. Various types of abnormalities to the test system have been simulated and for the simulation purpose CYME PSAF (Power System Analysis Framework) has been used.