Adaptive under frequency load shedding scheme based on dynamic security assessment

In this paper a new Dynamic Security Assessment (DSA) based Under Frequency Load Shedding (UFLS) scheme that is adaptive to system inertia and disturbance size is proposed. The proposed Adaptive UFLS scheme achieves a more precise estimate of the minimum shed for a range of system conditions. This reduces the cost of the UFLS as well as alleviating the risk of over shedding that would expose an already stressed system to an increased risk of secondary contingencies, which might lead to system blackout. Various scenarios with different wind levels have been simulated with results verifying the effectiveness of the method compared to semi adaptive UFLS methods.