Load Frequency Control of Deregulated Power System Using Different Fuzzy Controllers

Load frequency control (LFC) plays a vital role in power system operation and control. The LFC of deregulated system is to not only balance the generation and demand but to allocate generation between various systems. In deregulated environment, LFC is one of the ancillary services. With the help of conventional controllers, we cannot achieve better performance. To achieve better performance, a Fuzzy PID (FPID) controller is presented in this paper. The gains Kp, Ki, Kd are tuned from the knowledge base and fuzzy inference. To improve the system performance further, a multi-stage fuzzy controller is designed. The multi-stage controller uses the fuzzy switch to blend a proportional derivative (PD) fuzzy logic controller with an integral fuzzy logic input. It operates on fuzzy values, passing the consequence of a prior stage on to the next stage as fact. Simulations under three different scenarios are done, and its performance is compared with the FPID and PID controllers on the basis IAE, ITAE, ITSE performance indices.