Optimal Design of Six-phase Permanent Magnet Synchronous Generator for directdrive Small-Scale Wind Turbines

Permanent Magnet (PM) generators are widely employed in directly coupled wind turbines. Therefore, optimal design of these generators is quite necessary to improve their overall performance. In this paper, single/multi-objective design optimization of six-phase permanent magnet synchronous generator (PMSG) for directly coupled wind turbines is carried out. The studied PM generator in this paper is the radial-flux surface mounted PM generator. The aim of optimal design is to reduce the cost of PMSG manufacturing and generator losses. For this purpose, the main equations of PM generator design are extracted. Therefore, the generator design steps are developed and then imperialist competitive algorithm is used to optimize the design variables of the generator. To find the best design for this generator, the cost and losses, separately, are optimized and are then optimized simultaneously. Finally, the optimum results are presented. Comparison between optimum results shows that simultaneous optimization of the cost and losses leads to suitable design for PM wind generator.