Research Of Distribution Reactive Power Optimization Based On Modified Differential Evolution Algorithm

Optimal Reactive Power Flow (ORPF) in distribution network is an operation in which the structure parameters and load conditions of the distribution network system are given and under the premise to meet all the specified constraints, one or more performance indicators of the distribution network system are optimized by regulating some control variables. ORPF is an effective measure to keep power system safety and economic, and an important method to improve voltage equality.Considering that DE requires a relatively large population size to avoid premature convergence, in this paper we proposed a hybrid ABC assisted DE algorithm, which can reduce the required population size while improving the global search performance. Therefore, the hybrid algorithm can be applied in ORPF problem more effectively. First of all, we proposed an improved DE algorithm based on ABC. DE algorithm, which is based on the simple evolution driven by differences between individuals, does not take the individual quality into account in the evolution procedure. Therefore, referring to two ideas in ABC algorithm that onlooker bees determine their own foraging goals by relying on the feedback information of other individuals and scout bees search around their hives randomly, we add the bee colony accelerating evolution process in population evolution of DE, providing different local search opportunities for each individual according to the individual fitness distribution. The better the evolution of the individual is, the more opportunities for local search. At the same time, we provide a bee colony detecting operation for the individuals which have a continuous poor evolution, so DE can obtain better global search ability. Secondly, the effectiveness of DE-ABC is verified by the serial simulations on the IEEE14-bus and30-bus system test cases. The simulation results show, in the case of achieving the same effect, the required population size of DE-ABC hybrid algorithm is greatly less than that of DE algorithm, and the algorithm convergence time is less too. At last, we developed an ORPF system based on DE-ABC hybrid algorithm and the J2EE architecture, in this paper, a detailed introduction to this ORPF system was displayed, including the design of ORPF system, database design, as well as some interfaces of system functions.