Multi-Objective Bat Algorithm for Optimal Placement and Sizing of DG

Advancement of Distributed Generation (DG) technologies and market regulations have made DGs a clean and cost effective source of energy. Installation of DGs and their impacts on the performance of power systems can be realized by investigating proper location, size and type of DGs used. This paper considers, not only the reduction of real power loss and the voltage stability index (VSI) improvement as optimization objectives but also economic aspects of DGs. Multi-objective Bat Algorithm (MOBA) is proposed to find the Pareto optimal set for multi-objective (MO) functions by varying weights. Two cases are considered based on the types of distributed generation used. DG generating only real power is considered in Case I where as DG capable of generating both real and reactive power is investigated in Case II. Both cases are carried out on IEEE 69 bus distribution system with multiple DG units. A comparative analysis is performed to analyze the quality of non-dominated solution with different scenarios for both the cases. The best compromise solution for optimal location and capacity of DG is determined using a fuzzy decision making procedure. Simulation results confirm the efficacy of the multi-objective method presented in the paper.