Intelligent tuning of PID controller for voltage and frequency regulation in interconnected power systems

Abstract

Penetration of renewable energy sources makes the modern interconnected power systems to have more intelligence and flexibility in control. In electric power systems, the real and reactive power control plays a newlinemajor role on the satisfactory operation and the constancy of frequency and voltage are the main factors to achieve these power controls. This constancy of frequency and voltage are attained with two essential control loops such as Load Frequency Control (LFC) and Automatic Voltage Regulator (AVR). While, the primary control mechanism in LFC loop is provided with the speed governing system and in AVR system is provided with an exciter system correspondingly. In this research work, designing a suitable intelligent approach for newlineeffective tuning of gain parameters of Proportional Integral Derivative (PID) controller in the LFC and AVR loops in an interconnected power system is considered as a main problem objective. The chosen problem is formulated as anoptimization problem and the optimal gain parameters of PID controllers in LFC and AVR loops are computed with three innovative swarm intelligent algorithms such as Particle Swarm Optimization (PSO), Bacterial Foraging Optimization Algorithm (BFOA) and hybrid Bacterial Foraging Optimization Algorithm-Particle Swarm Optimization (hBFOA-PSO) algorithm. A comparative analysis is made between these three algorithms and the proposed hBFOA-PSO is found to be better compared to other two individual optimization algorithms (PSO and BFOA).The effectiveness of the proposed hBFOA-PSO algorithm for effective tuning of PID controller is tested in different structures of LFC system by various types of analysis. Initially, the proposed hybrid algorithm is applied for effective tuning of two-area LFC system with and without Governor Dead Band (GDB) non-linearity. Further, the study is extended to single-area multisource newlinepower system and multi- area multi- source power system with/without High Voltage Direct Current (HVDC) link. newline newline