In this paper, an advanced optimization algorithm named hybrid bacterial foraging particle swarm optimization (BFPSO) algorithm is proposed, for optimal tuning of proportional integral derivative (PID) controller of an automatic voltage regulator (AVR) system. An objective function, designed with fundamental time domain specifications is also considered in this research work. The effectiveness of the proposed approach is examined by the transient performances, stability and robustness of the system and also by the convergence characteristics of the proposed algorithm. The reliability of the proposed approach is investigated in this paper, by including the physical constraints such as parameter changes and nonlinearity such as band limited noise to the AVR system model. In this paper, a comparative study is also made with the earlier documented results of modern heuristic approaches namely, bacterial foraging optimization algorithm (BFOA), artificial bee colony (ABC) algorithm, and also with the conventional Ziegler Nichols (ZN) method to validate the superiority of the proposed approach. All the simulation results clearly prove that the proposed BFPSO tuned PID controller has better control performances compared to other optimization approaches.

Keywords: Automatic generation control, Automatic voltage regulator, Bacterial foraging particle swarm optimization algorithm, Proportional integral derivative (PID) tuning