反电势限幅对宽调速范围同步磁阻永磁电机设计的影响

Effect of the Back-EMF Limiting of Broad Adjustable Speed Synchronous Reluctance Permanent Magnet Motors

针对弱磁能力很强的同步磁阻永磁(SR-PM)电机的过高空载反电势会导致逆变器损坏的问题,提出了在电机设计时对其进行限幅的设计策略,并将其和通常的无限幅的设计策略进行了性能对比和参数优化.结果表明,无限幅策略主要考虑电机、逆变器成本的平衡,限幅策略的电机设计的瓶颈是用更小的电流产生低速下的转矩,因此必须充分利用SR-PM电机的磁阻特性产生转矩,但磁阻特性的利用依然存在一个上限.

A back-electromotive force （EMF） limiting design strategy is proposed to avoid damage to the inverters caused by the excessively high level back-EMF of the synchronous reluctance permanent magnet （SR-PM） motors with high field-weakening capability. Performance analysis and the parameter optimization of this strategy are compared with the conventional design strategy without back-EMF limitation. The results show that the cost trade-off between inverters and motors is the main consideration under the conventional design strategy. On the other hand, the bottleneck of the design with back-EMF limitation is how to produce enough torque at low speed with smaller current. Consequently, the reluctance characteristics of SR-PM motors must be fully utilized. However, there is also an upper bound of this utilization.