【作者】 刘海峰；

【导师】 孙向东； 周长攀； 郭亮；

【作者基本信息】 西安理工大学 ， 电气工程（专业学位）， 2022， 硕士

【摘要】 传统的三相电机出现故障时会立即停止运行,多相电机由于其相数的增加,使得容错运行成为它的一个显著优势,当其出现单相开路故障时,仅需采用容错控制策略就可确保电机实现不中断的运行,因此,多相电机在舰船舰艇、航空航天等对可靠性要求较高的领域具有很好的应用前景。本文以五相永磁同步电机(Permanent Magnet Synchronous Motor,PMSM)为研究对象,对其驱动控制系统和单相开路故障下的容错控制策略进行了研究。首先,介绍了五相PMSM不同坐标系下的数学模型。针对实际系统中逆变器死区效应造成的谐波电流问题,在d1-q1及d3-q3子空间中,分析了双空间调节的矢量控制策略,仿真结果表明谐波电流实现了较好的消除。同时,针对传统大矢量直接转矩控制(Direct Torque Control,DTC)策略没有很好地考虑谐波电压问题,研究了虚拟矢量DTC策略,通过仿真对比,结果表明虚拟矢量DTC策略具有较好的动、静态性能。其次,在单相开路故障情形下,分析现有容错DTC策略的不足,针对其需要重新划分扇区和再次设计开关表的问题,提出了一种虚拟矢量的间接修正方法,通过间接修正得到等幅值以及最大幅值虚拟矢量,并对最大幅值虚拟矢量的选取进行了分析,以达到较好的控制效果。同时分析了间接修正的最大幅值虚拟矢量与直接修正的虚拟矢量之间的联系。通过Matlab/Simulink完成容错DTC仿真模型,证实了所提容错DTC策略的正确性。再次,对于实际系统中,由于电机永磁体的加工及安装误差等影响,使磁动势含有一定的3次谐波磁势分量,针对该3次磁势分量导致的转矩脉动问题,分析了注入3次谐波电流的方法,同时根据不同的应用场合分析了最小铜耗以及最大转矩优化原则。针对传统PI控制器不能精确跟踪开路故障下生成的交流参考电流信号,研究了准谐振(Quasi Resonance,QR)+PI控制器实现交流参考电流的精确跟踪。通过Matlab/Simulink完成容错矢量控制仿真模型,对比验证了所研究方法的有效性。最后,根据系统总体方案搭建五相PMSM实验平台,通过实验验证了本文所研究容错控制策略的可行性和有效性。更多还原

【Abstract】 It will stop running immediately when the fault occurs for the traditional three-phase motor.Due to the increase in the number of the phases,the fault-tolerant operation has become a significant advantage for the multi-phase motor.In case of a single-phase open-circuit fault,only fault-tolerant control strategy can ensure the uninterrupted operation of the motor.Thus,the multi-phase motor has a good application prospect in ships,aerospace and other fields those require high reliability.The five-phase permanent magnet synchronous motor(PMSM)is taken as the research object in this thesis,the drive control system and the fault-tolerant control strategies under single-phase open-circuit fault are studied.Firstly,the mathematical models of five-phase PMSM in different coordinate systems are introduced.Aiming at the harmonic current problem caused by the dead-time effect of the inverter in the actual system,the vector control strategy of double-space adjustment is analyzed in the d1-q1 and d3-q3subspaces.The simulation results show that the harmonic currents are well eliminated.At the same time,aiming at the problem that the harmonic voltage are not well considered in the traditionall large vector direct torque control(DTC)strategy,the virtual vector DTC strategy is studied.The results show that the virtual vector DTC strategy has better dynamic and static performances by the simulation and comparison.Secondly,the shortcomings of the existing fault-tolerant DTC strategies are analyzed under single-phase open-circuit fault.Aiming at the problems of re-dividing sectors and redesigning the look-up table,an indirect correction method of virtual vectors is proposed.The equal amplitude virtual vectors and the maximum amplitude virtual vectors are obtained by indirect correction,and the selection of maximum amplitude virtual vectors is analyzed to achieve better control effect.At the same time,The relationship between the maximum amplitude virtual vectors of indirect correction and the virtual vectors of direct correction is analyzed.The fault-tolerant DTC simulation model by Matlab/Simulink is completed to verify the correctness of the proposed fault-tolerant DTC strategy.Thirdly,due to the influence of machining and installation errors of motor permanent magnet in the actual system,the magnetomotive force contains a certain 3rd harmonic magnetic potential component.Aiming at the torque ripple caused by the 3rd harmonic magnetic potential component,the method of injecting the third harmonic current is analyzed.And the optimization principles of minimum copper loss and maximum torque are analyzed according to different applications.Aiming at the traditional PI controller cannot accurately track the AC reference current signal generated under the open-circuit fault,the Quasi Resonance(QR)+PI controller is studied to realize the accurate tracking of AC reference current.The Matlab/Simulink simulation model of fault-tolerant vector control is built,and the effectiveness of the research methods are verified by comparison.Finally,the five-phase PMSM experimental platform is built according to the overall scheme of the system.The feasibility and effectiveness of the fault-tolerant control strategies studied in this thesis are verified by experiments.更多还原