Optimized fuzzy self-tuning PID controller design based on Tribe-DE optimization algorithm and rule weight adjustment method for load frequency control of interconnected multi-area power systems

Abstract

The reliable load frequency control (LFC) is addressed as one of the most important services in the modern electric power system operation and planning. Since the power systems have various structural and non-structural uncertainties, using control methods with fixed parameters may not yield the optimal performance of the system. Thus, in this research, a novel fuzzy PID controller is introduced to LFC for interconnected multi-area power systems in parametric uncertainties as well as external disturbances existence. The proposed algorithm adjusts the scaling factors and the modal parameters of input and output membership functions as well as the weights of fuzzy PID controller rule values. According to the transient response of the area control error (ACE) variable partitioning, the fuzzy rule weight values are obtained. Furthermore, in order to enhance the quality of the response, the scaling factors and the modal parameters of the input and output membership functions of fuzzy PID controllers are optimized by Tribe-DE (TDE) algorithm. The method is examined on the two and three area interconnected power systems at several conditions and an Integral of Time multiplied Absolute Error (ITAE) less than 0.0108 as well as an absolute maximum undershoot less than 0.0210 Hz for Δf1 regulation are obtained in the two area interconnected power system. Good transient behavior, disturbance rejection capability and insensitivity to parameter changes are advantages of the proposed controller.