120°相带环形绕组圆筒型永磁直线发电机定位力降低的优化设计

Optimal Design of a Tubular Permanent Magnet Linear Generator with 120°Phase Belt Toroidal Windings for Detent Force Reduction

圆筒型永磁直线发电机(TPMLG)采用120°相带环型绕组可以提高其功率密度,然而,TPLMG具有较大的定位力,这会引起发电机的振荡甚至使系统不稳定。为了解决这一问题,该文对120°相带环形绕组(120°-TPMLG)的圆筒型永磁直线发电机进行优化设计。首先利用有限元方法研究不同结构参数(定子铁心长度、极弧系数、槽肩宽度、定子齿宽和气隙长度)对定位力的影响。根据分析结果,结合田口方法对发电机进行优化设计,在不损失输出功率的情况下使定位力最小,得到120°-TPMLG的最优结构参数。为了验证优化设计过程的有效性,将优化后的120°-TPMLG与初始发电机的性能进行比较。结果表明,优化后的120°-TPMLG的定位力得到了极大的减小,输出功率也略有增加。因此,该文采用的优化方法对减小120°-TPMLG的定位力是有效的。

The utilization of 120°phase belt toroidal windings can bring power density improvement in a tubular permanent magnet linear generator(TPMLG).However,the TPMLG always suffers from large detent force,which would cause generator oscillation or even destabilize the system.To alleviate this problem,the optimal design of the tubular permanent magnet linear generator with 120°phase belt toroidal windings(120°-TPMLG)is conducted in this paper.The influence of different structural parameters(stator iron core length,pole arc coefficient,slot shoulder width,stator teeth width and air gap length)on the detent force is analyzed via finite element method firstly.According to these analytical results,the optimal design combined with the Taguchi method is implemented to minimize the detent force without losing output power,and the optimal structural parameters of the 120°-TPMLG are obtained.To verify the effectiveness of the optimal design process,the performance of the optimal 120°-TPMLG is compared with that of the original one.It is shown that the detent force of the optimal generator is largely decreased,and the output power is slightly improved,which proves that the proposed optimal design method is available in the detent force reduction of 120°-TPMLG.