Improvement of asynchronous starting characteristic for a line start permanent magnet synchronous motor

通过3篇论文、19次向日本电机工程师学会旋转机械技术会议和1次出版物等会议的口头报告，公布了研究成果。研究成果总结如下：(1)建立了直线启动永磁同步电机的分析理论：直线启动永磁同步电机的转子具有像感应电机的鼠笼式转子那样的永磁体和启动绕组。因此，LSPMM的分析理论非常复杂，因为必须考虑永磁体、启动绕组和转子铁结构的影响，所以还没有建立起通用的分析理论。我们提出了一种新的LSPMM的一般解析理论。(2)LSPMM的特性和常数的检验：为了确定分析方法中使用的常数，进行了一些试验。结果表明，稳态同步运行特性测试表明，LSPMM能够实现高效驱动；稳态异步测试表明，启动电流由三个不同频率的分量组成。感应电机和LSPMM的特性比较：采用10种不同间隙长度(0.25、0.30、0.35、0.40、0.45 mm)的四极和八极电机，从基频到基频的3.5倍频率运行，对其性能特性进行了详细的实验研究。结果表明，各驱动频率的一次阻抗损耗和杂散负载损耗(SLL)对总损耗有显著影响。(4)采用T型等效电路直接法可以较好地计算各驱动频率的无间隙负载损耗特性。

We were able to announce research results in 3 papers, 19 oral reports to conferences such as the Rotating machine Technical Meeting of the Institute of Electrical Engineers in Japan, and 1 publication.A summary of the research results follows :(1) Establishment of analytical theory for the line-start permanent-magnet synchronous motor (LSPMM):The rotor of LSPMM has some permanent-magnet and starting winding like as a squirrel-cage rotor of an induction motor (IM). Therefore, the analytical theory of LSPMM is very complex, because the influence of permanent-magnet, starting winding and rotor iron construction must be considered, so the general analytical theory has not established yet. We proposed a new general analytical theory for LSPMM.(2) Examination of the characteristics and constants of LSPMM :For the purpose of the determination of the constant used in the analytical method, some tests were carried out. As a result, it was clarified that LSPMM is able to be driven at high efficiency by the steady-state synchronous operating characteristic test, the starting current consists of three components with different frequency by the steady-state asynchronous test. The frequencies of starting current verifies the justification of our analytical theory.(3) Comparison of the characteristics of induction motor with LSPMM :Using 10 types of 4-pole and 8-pole IMs with different gap length (0.25, 0.30, 0.35, 0.40, 0.45mm), and operated from based frequency to 3.5-times frequency of based frequency, the performance characteristics were investigated experimentally in detail. As a result, it is clarified that the total loss is remarkably affected by the primary resistance losses and the stray load loss (SLL) with the gap length for each driven frequency.(4) The IM characteristics can be calculated relatively well without the SLL for every drive frequency by employing the type T equivalent circuit direct method.