A New Adaptive Under-Frequency Load Shedding Scheme for Multi-Area Power System, 1-10.

Abstract

Under-frequency load shedding (UFLS) is a critical function of frequency control in a power system. This paper presents a new adaptive UFLS scheme in multi-area power systems, where the frequency thresholds and load to be shed are adapted to the severity of the disturbance in each control area. In this approach, the frequency thresholds are adapted by a fuzzy logic controller using the rate of change of frequency (RoCoF), the tie-line transit, the amount of load to be shed is estimated according to the available tie-line capacity and spinning reserve. The objective is to avoid the collapse of the power system following a major disturbance, by shedding a sufficient amount of load while avoiding the tripping of the tie-lines. Numerical simulations are performed on the multi-area Algerian transmission power system and used to demonstrate the effectiveness of the proposed approach compared to the conventional and adaptive approaches. The results show the effectiveness of the proposed approach, with a better quality of frequency control by adapting the amount of load shedding to the severity of the disturbance, and ensuring a better stability of the system by avoiding tripping of the tie-lines.