双三相永磁同步电机的效率优化及容错控制技术研究

Multiphase motors enjoy the advantages of low-voltage high power, low-torque pulsation, and good fault tolerant ability. They are suited for application fields such as electric vehicles, electric ship propulsion and aerospace applications. With the dual three-phase permanent magnet synchronous motor (PMSM) as the research object, the common problems of harmonic loss, fault diagnosis and fault tolerant control in the current multiphase machines research well be deeply studied. The strategy of bus voltage optimal utilization is proposed in this project. The total vector control range was divided into three regions, and the PWM strategies and harmonic currents suppression strategies for different control regions are studied. And the efficiency optimization of full voltage modulation range is achieved. A novel solution for fault-tolerant in the case of a fault in one leg of the six-leg inverter is proposed in this project. Compared with the commonly used fault-tolerant control strategy due to open phases, this strategy has the advantages of without increasing the stator copper, reducing the torque ripples and implementing easily. The vector control, direct torque control, predictive current control and other strategies are contrastive studied for the dual three-phase motor under five-leg running. Achieve a complete fault-tolerant control solution which includes inverter open circuit fault diagnosis and the transition from fault to fault-tolerant operation for the dual three-phase motor. The research results and findings can constitute the theory and technology system for fault-tolerant based on five-leg running in the case of a fault in one leg of the six-leg inverter.

多相电机驱动系统具有低压大功率输出、低转矩脉动、适于容错运行等优势，特别适用于电动汽车、舰船电力推进、航空航天等领域。本项目以相移30°双三相永磁同步电机为研究对象，针对目前多相电机研究中存在的谐波损耗、故障诊断与容错控制等共性问题进行深入探索研究。提出双三相电机的母线电压最优化利用策略，将双三相电机的矢量控制分为三个控制区，研究适用于不同控制区的PWM策略以及谐波电流抑制策略，实现全电压调制范围的效率优化。提出一种新颖的基于五桥臂运行的双三相电机一相桥臂故障容错控制方案，与常用的缺相容错运行控制策略相比具有不增加定子铜耗、降低转矩脉动且易于实现等优点。对比研究双三相电机五桥臂运行时的矢量控制、直接转矩控制、预测电流控制等策略。实现双三相电机系统逆变器开路故障诊断、故障运行到容错运行的在线切换完整的容错控制解决方案，形成基于五桥臂运行的双三相电机一相桥臂故障容错控制的理论与技术体系。

多相电机驱动系统具有低压大功率输出、低转矩脉动、适于容错运行等优势，特别适合应用于电动车，风力发电、航空航天等领域。以相移30°双三相永磁同步电机(PMSM)为研究对象，对数学建模、谐波电流抑制方法、PWM策略、容错控制等方面进行深入探索研究。构建一种双三相电机双平面SVPWM算法，基于矢量空间解耦模型，通过矢量合成的方法，分别在a-b子平面和z1-z2子平面构建虚拟矢量，实现对a-b和z1-z2子平面参考电压矢量的独立控制，即可以实现双三相电机双平面四维电流矢量控制，更好地抑制谐波电流，实现了对六相逆变器死区效应等非线性因素的补偿；构建一种新颖的五桥臂逆变器驱动双三相电机系统控制策略。包括相位差90°、相位差150°和相位差30°共用方式三种情况，其中相位差150°共用方式下双三相电机可以和电机六桥臂正常运行时输出同样的最大转矩能力，但是其直流母线电压利用率较低。相位差30°共用方式直流母线电压利用率最大为0.408Udc，但输出转矩范围降低。五桥臂逆变器驱动双三相电机系统控制策略可以作为六相电压型逆变器一相故障时的新的容错方案，解决了传统缺相容错控制方案会增加定子铜耗、转矩脉动较大的问题，并且易于实现。提出了五桥臂逆变器驱动双三相电机直接转矩控制策略；研究了双三相电机系统缺一相故障后电压矢量的分布情况，提出了双三相电机系统缺一相故障运行时虚拟矢量的修正方法。构建一种新颖的双三相电机缺一相故障直接转矩控制策略，其定子磁链分区和开关表的选取规则与双三相电机正常运行时一致，其差别只是虚拟矢量的幅值有所减少，因此比较易于实现。提高了双三相电机驱动系统的故障容错能力。