永磁容错电机磁阻转矩的提升机理与容错控制

The reliable operation of electric vehicle drive system is an important guarantee for people's safety. Fault tolerant permanent magnet (PM) motor offers high torque density, high efficiency and high reliability, which has become a research hotspot. In order to solve the problems of improvement and utilization of reluctance torque in existing fault tolerant PM motor, a novel fault tolerant PM motor with improved reluctance torque and a fault tolerant control with consideration of reluctance torque are proposed. According to the unity between the period of inductance pulsation and the number of poles, the magnetic pole is design as asymmetry. Then, the rise and fall intervals of self-inductance are regulated to increase the reluctance torque. Meanwhile, the maximum torque per ampere control for fault tolerant operation is built to track maximum torque point under fault. Additionally, the amplitudes and the adjustment angles of fault-tolerant currents are obtained on the basis of equal torque of pre and post fault. Then, the reluctance torque can be used under the fault. Based on the analysis of the ripple of PM torque and the reluctance torque under fault, the intrinsic relationship among the current amplitude, the adjustment angle and the torque ripple can be explored. Then, a fault control strategy for reducing torque ripple is presented with coordination control between the PM torque and the reluctance torque. Moreover, overall performance of proposed drive system is experimentally analyzed and evaluated. The basic problems of science can be clarified, and the mechanism for improving the reluctance torque of fault tolerant PM motor is revealed. The general rules for the design and control of the fault-tolerant PM motor drive system are explored with consideration of the reluctance torque characteristic. This project lays theoretical and experimental foundations for their applications.

电动汽车驱动系统的可靠运行是人们生命安全的重要保障。永磁容错电机因其高转矩密度、高效率和强容错的优势，已成为研究热点。克服现有永磁容错电机难以提升和利用磁阻转矩的弊端，提出一类磁阻转矩增强型永磁容错电机，并研究考虑磁阻转矩的容错控制。基于电感脉动周期数与磁极数的一致性，采用非对称性磁极设计，通过改变自感的上升和下降区间来提升磁阻转矩；构建容错式最大转矩电流比控制，追踪故障后的最大转矩点；在故障前后转矩相等的前提下探寻容错电流幅值和调整角，解决故障下利用磁阻转矩的难题；分析故障下的永磁转矩和磁阻转矩脉动规律，归纳电流幅值、调整角和转矩脉动的内在联系，利用永磁转矩和磁阻转矩协调控制，实现故障后转矩脉动抑制；搭建实验平台，进行系统综合性能的分析与评估。提炼基础科学问题，揭示永磁容错电机磁阻转矩的提升机理，探索考虑磁阻转矩特性的永磁容错电机与容错控制的一般性设计方法，为其应用奠定理论和实验基础。

电动汽车驱动系统的可靠运行是人们生命安全的重要保障。永磁容错电机因其高转矩密度、高效率和强容错的优势，已成为研究热点。针对现有永磁容错电机磁阻转矩提升难与利用难的瓶颈问题，项目组从精确分离永磁转矩和磁阻转矩出发，提出考虑交直轴交叉耦合和磁饱和的转矩分离方法；阐明槽极配合、绕组结构与电机电感、磁阻转矩、凸极率的内在联系，采用多目标优化算法，提出兼具磁阻转矩和凸极率的永磁容错电机，增强永磁电机弱磁与无传感器运行时的容错能力；克服高磁阻转矩附带的高转矩脉动难题，从转矩产生原理出发，构建电机磁动势分析模型，探明电机结构参数与转矩脉动阶次的联系，揭示永磁容错电机转矩脉动抑制机理；提出一种基于空间电压矢量的高频信号注入方法，将高频信号直接注入逆变器，克服传统最大转矩电流比控制算法中注入信号的频率受比例积分控制器带宽限制的这一弊端；为了消除真实高频信号注入引起的高频损耗，提出一种适用于容错运行的虚拟信号最大转矩电流比算法，将高频信号注入电机故障数学模型中，利用转矩与电流角偏导获取故障后的理想工作点并拓展至容错运行状态，准确追踪故障下的最大转矩。突破传统容错控制故障后不能利用电机磁阻转矩的瓶颈，显著提升电机系统效率。基于以上研究，项目组在中国科学、中国电机工程、电工技术学报、IEEE Transactions等国内外权威期刊发表论文20篇，其中一区论文11篇、ESI高被引论文1篇；授权美国发明专利1件、中国发明专利4件；获江苏省科学技术二等奖1项，江苏省优秀硕士学位论文1篇。