低速高效垂直轴风力发电机及其特性分析

Low speed high efficiency generator and performances analysis for vertical axis wind power

针对低风速区风力发电机需要低风速切入问题,研究了一种低速高效的定子无铁芯轴向磁通永磁风力发电机。对影响发电机性能的关键参数对进行了归纳,提出了一种单层非重叠集中绕组和优选"切饼"型磁极组合的设计理念。确定了定子无铁芯轴向磁通永磁风力发电机性能分析参数方案。利用三维有限元发电机设计平台,对发电机的空载输出特性,交、直流负载输出特性和不同转速下的负载输出特性进行了对比研究。研究结果表明,该结构发电机的各项基本电磁参数和输出特性均能满足低速风力发电系统的特殊要求:优选的磁极结构使发电机总永磁体耗用量节约11.5%,发电机最大输出效率达87.75%;低转速范围运行时,效率维持在85%以上;不同工况下输出电能总谐波畸变率低于3%。

Aiming at the problem of wind generators need to cut-in low wind speed in low wind speed areas, a coreless stator axial flux per- manent magnet generator with low speed and high efficiency was studied. The key parameters that affected the performance of generator were summarized, the design concept which combined a single layer non-overlapping concentrated winding and the optimization of ＂cut cake＂ type magnetic pole shape was proposed, and the parameter scheme of performance analysis of the coreless stator axial flux permanent magnet wind generator was determined. The three dimensional finite element generator design platform was utilized to study contrastively the load output characteristics of the no load, AC load and DC load and different speeds of the generator. The result indicate that the basic electromagnetic parameters and output characteristics of the structure generator are able to meet the special requirements of low speed wind power generation system： the consumption of the permanent magnet materials is saved about 11.5% by appling the optimization magnetic polelshape, the gen- erator maximum output efficiency is up to 87.75% ; the efficiency is maintained at more than 85% in the low speed range, the total harmonic distortion （THD） of the electric energy output under different working conditions is less than 3%.