多相电机非正弦供电下的磁密优化及容错控制策略研究

Multiphase motor drives have some advantages over conventional three-phase drives, such as high torque density, high power density and fault-tolerant capability. Multiphase motor drives are suitable for high power industrial applications, such as electric ship and locomotive traction. Concentrated full-pitch winding structure and non-sinusoidal power supply are usually adopted to improve iron core utilization and torque density. Flux density optimization and coupling mechanism analysis under fault condition are new research topics for non-sinusoidal power supply technique. According to winding function theory and magnetomotive force analysis, the following topics are discussed: (1) double optimization objectives and constraints are introduced. Then, the ratio and phase relationships between fundamental current and harmonic currents are derived to improve air-gap and yoke flux density distribution under various loads; (2) coupling mechanisms between fundamental and harmonic planes under fault condition are revealed, and harmonic current effects on torque ripple are analyzed. A fault-tolerant control strategy is proposed to achieve minimum torque ripple under fault condition. The project aims to solve two key technical problems for non-sinusoidal power supply theory, and the concrete implementation plans are demonstrated in detail.

多相电机系统具有高转矩密度、高功率密度、高可靠性等特点，特别适合在机车牵引、舰船推进等大功率驱动场合应用。多相电机常采用集中整距绕组和非正弦供电方式，以提高铁芯利用率和转矩密度。多相电机非正弦供电下的磁密优化和故障状态谐波磁场耦合，是非正弦供电技术新的研究内容。本申请项目从绕组理论及磁动势等角度综合分析，探讨和解决如下问题：(1)引入两个优化目标与约束条件，推导注入谐波电流的比例系数与相位，实现变化负载下的气隙和轭部磁密双重优化；(2)揭示故障状态下基波平面与谐波平面的耦合机理，分析谐波电流对转矩脉动的影响，提出一种非正弦供电下的最小转矩脉动容错控制策略。本项目旨在解决非正弦供电理论的两个关键技术问题，提出多相电机非正弦供电的具体实施方案。

多相电机主要应用在机车牵引、舰船推进、航空航天及飞轮储能等大功率场合，对功率密度、可靠性等具有较高的要求，采用非正弦供电技术能有效提高上述指标。尽管多相电机非正弦供电技术是当前的研究热点之一，但对集中整距绕组结构和非正弦供电技术研究仍远远不够。本项目正是致力于多相电机系统的非正弦供电技术研究，详细分析了谐波磁场对电机磁密分布的影响，揭示了非正弦供电下故障状态的耦合机理，具有重要的理论价值与现实意义。上述理论研究成果以论文和专利形式展现，以第一或者通讯作者发表了国际一流期刊IEEE Transaction 11篇，中文EI期刊1篇，授权或者申请发明专利5项。在此基础之上，项目负责人将多相电机的研究成果，应用于中国航发集团航空发动机燃油泵和电力作动器等重要场合，充分发挥了多相电机的可靠性与容错特性，是本项目成果转化的有力支撑。