可变磁通永磁游标电机设计及静态特性分析

为实现永磁电机在体积和槽数不增加情况下产生低速大转矩输出,将混合励磁概念引入永磁游标电机,提出了一种新型可变磁通永磁游标电机。通过将磁通调制极引入到电机定子齿以及在相邻磁通调制极间布置励磁绕组,实现了电机磁通可控,从而保证在增磁及弱磁过程中宽调速范围运行。分析了其工作原理,采用时步有限元方法计算了电磁特性,包括空载永磁磁链、空载感应电动势、齿槽转矩和输出转矩,对其增磁弱磁过程进行了分析。制作了一台1 kW样机;并对其静态特性进行了测试。结果表明该电机具有转矩密度大、齿槽转矩小、调速范围宽特点,适用于风力发电、电动汽车领域。

Design and Static Characteristics Analysis of Flux-Controllable Permanent Magnet Vernier Machine

In order to obtain the low speed large torque output of permanent magnet synchronous machine (PMSM) with no increasing bulk and stator/rotor slot numbers, one novel flux-controllable PM Vernier machine (FCPMVM) was proposed by introducing the concept of hybrid excitation. The magnetic flux of the proposed FCPMVM was controllable due to the emplacements of flux modulation poles (FMPs) and excitation winding in stator teeth and the adjacent FMPs, respectively, which brings wide range operation through the processes of flux-enhancing and flux-weakening. The working principle of the proposed machine was deeply studied, as well as basic electromagnetic characteristics were calculated by time stepping finite element method, including no-load magnetic flux linkage, no-load back electromotive force, cogging torque and output torque. In addition, the processes of flux-enhancing and flux-weakening were analyzed. Finally, one prototype with 1kW was built and its static characteristic was tested. The results show that the proposed FCPMVM has the characteristics of high torque density, small cogging torque and wide speed range, which is one promising candidate for fields of wind power generation, electric vehicle.