气隙调衡式混合励磁直线同步电机特性

针对直线电机无绳提升系统中因气隙不均匀引起的轮轨间振动、噪声和磨损等问题，设计新型的混合励磁直线电机. 通过改变次级励磁电流来调节双边气隙磁场和法向电磁力，进而调节双边气隙平衡，有效地降低轮轨间压力. 介绍新型电机的拓扑结构及气隙磁场调节原理，分析主要结构参数对电机性能的影响，确定样机的基本参数. 研究不同负载工况下次级励磁电流对法向电磁力的调节特性，分析次级励磁电流对直线电机空载反电势和电磁推力的影响. 研究结果表明，次级直流励磁电流对电机法向电磁力具有良好的调节能力，对电机推力输出基本没有影响. 在相同的负载工况下，法向电磁力随次级直流励磁电流基本呈线性变化. 当电机负载增大时，直流励磁电流对法向电磁力的调节能力略有降低. 实验结果与有限元分析结果基本吻合，验证了本文理论分析的正确性.

Characteristic of air gap balanced hybrid excitation linear synchronous motor

A novel hybrid excitation linear motor was designed aiming at the problems of vibration, noise and wear between wheel and rail caused by uneven air gap in linear motor ropeless lifting system. The magnetic field and normal force were adjusted by changing the secondary current. Then the bilateral air gap was evenly adjusted to reduce the pressure between wheel and rail. The topology of new motor and the principle of air gap magnetic field adjustment were introduced. Then the influence of structural parameters on motor performance was analyzed, and the parameters of the prototype were determined. The regulation performance of secondary excitation current on normal force was analyzed under different load conditions. Then the effects of secondary DC excitation current on no-load back EMF and thrust were analyzed. Results show that the DC excitation has a significant effect on the normal force and has little effect on the thrust of the motor. The normal force changes linearly with DC excitation current under the same load condition. The regulation ability of DC excitation current to normal force decreases slightly when the load increases. The experimental results basically accorded with the finite element analysis, which verified the correctness of the theoretical analysis in this paper.