LOCAL BEST EMBRANCHMENT BASED CONVERGENCE GUARANTEE PARTICLE SWARM OPTIMIZATION AND ITS USE IN TRANSMISSION NETWORK PLANNING

Summarized some improved methods of Particle Swarm Optimization(PSO),analyzed its critical reasons of convergence dilemma,then put forward local best embranchment optimization method,which consists of five elements:determination of local optimum;lock of local optimum area;embranchment search in local optimum area;particles recruitment in main search process and termination criterion.And a local depth optimization method based on retrogress mode of constructive heuristic algorithm according to the characters of transmission network expansion planning is also put forward.Numerical simulation results demonstrate these two methods overcome the convergence dilemma,improved the search efficient and ensured its local and global search ability simultaneously.They also provide new ideas for other optimization methods.