Optimal VAR Dispatch Using Elitist Multi-objective Biogeography Based Optimization

Abstract

Problem of Optimal VAR dispatch is generally modelled as a constrained nonlinear multi-objective optimization problem where load bus voltage deviation and real power transmission loss are to be minimized simultaneously. In this work we present an elitist Multiobjective Biogeography Based Optimization (e-MBBO) algorithm for solving optimal VAR dispatch problem in power system. Single objective Biogeography based optimization (BBO) algorithm is extended to multiobjective Biogeography Based Optimization (MBBO) by using the concept of crowded nondominated sorting. An efficient elitism is also incorporated to prevent detoriation of good solution from previous generation. The proposed e-MBBO is tested and validated on standard IEEE 30-bus and IEEE 57-bus test systems and the results were compared with that obtained by NSGA-II, MOPSO and SPEA-II using three performance metrics. The performance metric includes C-metric, Delta Spread and Hypervolume ratio. Simulation results demonstrate the effectiveness of the proposed e-MBBO in solving the optimal VAR dispatch problem.