Design optimization and evaluation of different wind generator systems

With rapid development of wind power technologies and significant growth of wind power capacity installed worldwide, various wind generator systems have been developed and built. The objective of this paper is to evaluate various wind generator systems by optimization designs and comparisons. In this paper, seven variable speed constant frequency (VSCF) wind generator systems are investigated, namely permanent magnet synchronous generators with the direct-driven (PMSG_DD), the single-stage gearbox (PMSG_1G) and three-stage gearbox (PMSG_3G) concepts, doubly fed induction generators with the three-stage gearbox (DFIG_3G) and with the single-stage gearbox (DFIG_1G), the electricity excited synchronous generator with the direct-driven (EESG_DD), and the VSCF squirrel cage induction generator with the three-stage gearbox (SCIG_3G). Firstly, the design models of wind turbines, three/single stage gearbox and power electronic converter are presented; design optimizations of the investigated wind generator systems are developed with an improved genetic algorithm. Next, the optimization designs are implemented of various wind generator systems at 0.75-MW, 1.5-MW, 3.0-MW, 5.0-MWand 10MW, respectively. The annual energy production (AEP) per cost are evaluated for a given wind climate. The comparative results show the wind generator system with the single-stage gearbox could be the most attractive choice, especially the DFIG_1G system.