大气隙外笼型转子磁力耦合器设计及性能研究

Design of long air gap external-cage rotor magnetic coupler and research on its performance

采用Halbach单侧聚磁特性,设计出了一种大气隙外笼型转子磁力耦合器(Long Air Gap External-cage Rotor Magnetic Coupler,LAEMC),并分析了其运行特性、调速特性及散热特性,推导出LAEMC电磁转矩解析表达式,据此分析了结构参数对电磁转矩的影响,得出了不同磁化比的Halbach结构对LAEMC电磁转矩的影响规律;根据LAEMC的运行特性,分析了其在离心式负载、恒功率负载及恒转矩负载的调速特性,表明其仅适合离心式负载调速并具有良好的节能效果;在离心式负载转差率为33%处的最大功率损耗点对LAEMC进行热仿真计算,得到永磁体工作温度约为60℃,而通过气隙与之相隔的笼条温度约为360℃,两者温度差达300℃以上,表明所提出的大气隙外笼型转子磁力耦合器———LAEMC在离心式负载上既具有良好的运行特性也具有良好的隔热效果。

In this article,the Halbach’s single-sided magnetization characteristics are used to design a long air gap externalcage rotor magnetic coupler(LAEMC);its operation characteristics,speed-regulation characteristics and heat-dissipation characteristics are analyzed.The analytical expression of the LAEMC electromagnetic torque is derived.Then,the analysis is conducted on the influence of the structural parameters on the electromagnetic torque;the law of the influence of the Halbach structure with different magnetization ratios on the LAEMC electromagnetic torque is identified.According to the operation characteristics of LAEMC,the analysis is conducted on its speed-regulation characteristics with the centrifugal load,the constant power load and the constant torque load.It is shown that LAEMC is only suitable for centrifugal-load speed regulation and has good energy-saving effect.LAEMC is subject to thermal simulation and calculation at the maximum power-loss point where the centrifugal-load slip rate is 33%.The results show that the working temperature of the permanent magnet is about 60℃,and the temperature of the cage bar separated by the air gap is about 360℃,with the difference of more than 300℃.It is indicated that the long air gap external-cage rotor magnetic coupler(LAEMC),has both ideal operation characteristics and desirable heat-insulation effect when the centrifugal load is exerted.