考虑谐波耦合的多相电机容错运行及效率优化方法的研究

Multiphase motor (phase n>3) with concentrated windings is fed by non sinusoidal power supply, in order to improve output power density. Harmonic currents (1st,3rd,5th harmonic in 7-phase motors) are no longer 'natural decouple' in fault-tolerant operation, which results in bigger torque pulse and rotor power loss. This project studies the harmonic magnetic coupling of multiphase motor in different control methods under the fault conditions with non sinusoidal power supply, aiming to output stable torque, so as to improve the reliability of drive system. After comprehensive analysis, harmonic magnetic coupling and its influence on the loss and torque of motor is discussed ; Methods by introducing additional stationary fields (or MMF) to reconstruct the currents of the healthy windings under fault conditions are proposed, which helps us study the harmonic coupling and its impact under motor open-phase fault, and to weaken the negative influence by selecting the appropriate constraints to reduce the negative effects of harmonic coupling. Based on it, fault-tolerant strategies are studied: the non-sinusoidal fed strategy under fault conditions; efficiency optimization under different loads and operating conditions; and analysis of the motor temperature and of reasonable load reduction under fault-tolerance operation. Test platform is also built up to improve the fault-tolerant operation strategies.

多相电机（相数n>3）常采用集中整距绕组和非正弦供电方式，以提高电机铁芯的利用率和功率密度。本项目研究多相电机在非正弦供电方式下的缺相容错运行策略。容错运行中，多相电机中的各次谐波（如七相电机中的1、3、5次谐波）不再如正常运行时那样“自然解耦”，这会导致转矩脉动增大、转子铜耗增大的不利影响。项目在分析故障运行时的谐波耦合后，提出了在容错模型中通过引入附加的驻波磁场来重构电流，既便于研究电机容错运行时谐波间的耦合和影响，又为通过选择合适的约束条件来降低谐波耦合的不利影响提供了途径。在此基础上探索了计及谐波耦合的非正弦供电方法以提升电机性能；研究了不同负载和工况下电机的效率优化；分析了容错运行时电机的局部温升和合理的降载程度；研制试验样机，并构建控制和测试平台，完善了电流的快速准确跟踪的算法，探索了高效、低转矩脉动、易于实施的容错运行策略，以提升多相大功率传动系统故障运行时高可靠性。

多相电机（相数n>3）常采用集中整距绕组和非正弦供电方式，以提高电机铁芯的利用率和功率密度。本项目分析了多相电机的多自由度和谐波空间特性，研究了多相电机的矢量控制和弱磁控制，研究多相电机在非正弦供电方式下的缺相容错运行策略。容错运行中，多相电机中的各次谐波（如七相电机中的1、3、5次谐波）不再如正常运行时那样“自然解耦”，这会导致转矩脉动增大、转子铜耗增大的不利影响。项目在分析故障运行时的谐波耦合后，提出了在容错模型中通过引入附加的驻波磁场来重构电流，既便于研究电机容错运行时谐波间的耦合和影响，又为通过选择合适的约束条件来降低谐波耦合的不利影响提供了途径。在此基础上探索了计及谐波耦合的非正弦供电方法以提升电机性能；研究了不同负载和工况下电机的效率优化；研制试验样机，并构建控制和测试平台，完善了电流的快速准确跟踪的算法，探索了高效、低转矩脉动、易于实施的容错运行策略，以提升多相大功率传动系统故障运行时高可靠性。