Toward a wide-area load shedding scheme: Adaptive determination of frequency threshold and shed load values

Conventional under frequency and under voltage load shedding (UFLS and UVLS) schemes are generally independent than each other. Besides, in these schemes, the operating thresholds, amounts, and location of shed loads are settled in constant values for different disturbances. Due to these technical flaws, the conventional load shedding schemes fail to retrieve power system stability which outlines the necessity of devising improved adaptive mechanisms. To this end, the ongoing study proposes an adaptive UFLS scheme based on wide area measurement systems (WAMS). In contradiction to the existing methods, the proposed approach is featured with an adaptive manner. In other words, the frequency threshold of load shedding relays is adaptively tuned at each disturbance. Furthermore, a wide-area index is proposed to select the amount of required shed loads. Extensive numerical studies conducted on a real-world case study are involved to evaluate performance of the proposed approach.