A Study of Co-evolutionary Genetic Algorithm in Relay Protection System

In view of the coordination difficulty problems existing in relay protection system and high security demand of power supply, the global optimization model for protection settings was set up in power supply network based on the analysis of relay characteristics. A new multi-parameter co-evolutionary genetic algorithm, used to optimize the protection settings, was presented and improved with establishing sub-population, cooperative operator and density operator. According to the specific demands of relay protection, the constraint interval coding method was adopted and the weight coefficients in the model were studied. The model with its algorithm was validated with an distribution system test that gave the applicable results. Security and reliability can be effectively guaranteed based on the integrated operation time decreasing in power supply network.