A quick method for electrical energy system load shedding based on equivalent areas

The main purpose of the paper is to present a fast load shedding scheme, based on the concept of equivalent areas in large power systems. Performing load shedding on such systems with several generators in each area by using the conventional method is consuming a large amount of time. The proposed method can significantly reduce energy not supplied and is absolutely affordable for not only energy producers, but also energy consumers. At first, the coherent generators in the network will be detected based on a generation acceleration technique. The coherent generators will be identified without performing transient stability studies or the comparison of rotor swing angles, and only will be detected by using Jacobian matrix elements of the linearized power system model. Each group of the coherent generators will be replaced by an equivalent generator to introduce a new reduced model. All analytical calculation and decision variable factors will be achieved centrally with mentioned model and the only signal sends to the network, is a load shedding command. UVLS technique will be applied to the load shedding scheme. In this method, the priority is to shed the busloads with the most amplitude of the voltage drop after disturbance, so the network voltage and frequency stability will be maintained. The scale of load shedding level is proportional to online mismatch power between generation and demand. Finally, a simulation of the standard 39-buses IEEE network will be carried out to prove the strategy’s effectiveness.