Optimal Reactive Power Dispatch of Power System using Improved Harmony Search Algorithm

Abstract

This paper presents improved harmony search algorithm (IHSA) to solve multi-objective optimal reactive power dispatch (ORPD) problem by minimizing active power loss,voltage deviation and voltage stability index. To acclerate the convergence speed and to enhance the solution quality dynamic pitch adjusting rate and variable band width are incorporated in orginal harmony search algorithm (HSA). In this work IHSA is used to find the settings of control variables such as generator voltages, tap positions of tap changing transformers and amount of VAR injection. The proposed IHSA is implemented on IEEE 30 and 57 bus systems and the results are compared with other computational intelligence-based techniques such as particle swarm optimization (PSO) and differential evolution (DE). A comparison of simulation results reveals the effectiveness of proposed algorithm over other well established population based optimization techniques.