Differential evolution applied for reliability optimization of radial distribution systems

This paper describes a methodology for reliability enhancement of radial distribution system by determining optimal values of repair times and failure rates of each section. Penalty cost functions have been constructed as function of failure rates and repair times. Constraints on customer and energy based indices, i.e. SAIFI, SAIDI, CAIDI and AENS have been considered. The problem has been decomposed in two stages. One stage determines the optimum failure rates and second stage optimizes repair times satisfying constraints. A population based approach, i.e. differential evolution (DE) has been used as optimization technique. The algorithm has been implemented on a sample test system. Results obtained have been compared with those obtained using particle swarm optimization (PSO) and co-ordinated aggregation based particle swarm optimization techniques (CAPSO).