Blended biogeography based optimization based LFC controller applied to multi-unit

This article proposes design and implementation of an evolutionary algorithm, named blended biogeography based optimization (BBBO), to solve load frequency control problem (LFC) in an interconnected power system network. Two area multi-unit multi-source power system network equipped with classical PI/PID controller is considered for the present study and dynamic responses of the same is investigated. The superiority and effectiveness of BBBO tuned PI/PID controller is examined by an extensive comparative analysis with the performance obtained by Zeigler Nichols (ZN) and genetic algorithm (GA) based classical controller, fuzzy gain scheduling (FGS), variable structure based FGS controller. The robustness of proposed controller is examined with different loading conditions and different performance indices. Furthermore, the study is extended to a nonlinear power system network considering governor dead band (GDB) and boiler dynamic nonlinearities.