横向磁通高温超导直线感应电机的电磁机理与交流损耗研究

This project in the study of the structure and performance characters of the classic convention linear inducting motor, convention PM linear motor and high temperature superconducting motor proposed a scheme of transverse magnetic flux high temperature superconducting linear induction motor to solve a series of problems of linear motor, such as low power density of motor, magnetic dependency, anisotropy, and poor banding characters of HTS. HTS material is used to improve the power density of the motor. By changing the arrangement of the HTS coil in the motor slot, the magnetic circuit is optimized to improve the working current under the complex background magnetic field and then to improve the motor performance. The accurate subdomain model is used to rapidly and accurately solve the key parameters of the HTS motor. The minimum magnetic energy entropy method is used to calculate the ac loss of HTS windings. This scheme is an innovation in motor structure designing and new materials applying and new method applying. The theoretical study and measurement on the electromagnetic mechanism, structure principle and ac loss of the motor can provide theoretical basis and develop calculation tools for further applied research in the future.

本课题在研究国内外典型常导体直线感应电机、常导体永磁同步直线电机、高温超导电机的结构及性能特点的基础上，针对直线感应电机功率密度偏低，高温超导材料具有磁场依赖性、各向异性及弯折性差等特点，提出横向磁通高温超导直线感应电机方案。采用高温超导材料提高电机的功率密度；通过改变超导线圈在电机槽内的布置方式优化磁路提高线圈在复杂背景磁场中的工作电流，提高电机性能；采用精确子域模型以解析方法快速精确求解超导电机内部各参量。采用最小磁能熵法精确求解超导绕组的交流损耗。该方案是一项电机结构设计的创新，是新材料、新分析方法应用的创新。通过对电机的电磁机理、结构原理、交流损耗进行理论研究与试验，可以为今后进一步开展应用型研究提供理论依据与计算工具。

本课题针对现有高温超导电机存在的高温超导材料电气参数非线性，求解速度慢，精度查的问题，提出了基于最小磁能熵增原理的建模求解法。通过寻找熵增最小的电流分布，快速求解超导材料的电气参数，该模型比常用的H方法求解速度快10倍以上，且求解精度更高；针对超导线圈存在端部电阻引起环流的问题，提出了端部耦合模型，可明确因端部电阻引起的附加损耗的变化规律。研究结果表明，端部电阻引起的附加损耗存在明显的阻值依赖性和频率依赖性。可通过合适阻值控制，将附加损耗控制在可接受的范围内。而且，对于双股并绕结构的超导线圈，该附加损耗值较小。利用本课题中所提出的计算方法及线圈结构，可以直接服务于高温超导变压器、超导限流器等先进高温超导电气设备的研制，对于高温超导电气设备的研发与推广具有重要意义。