基于分段调制策略的永磁同步电机直接转矩控制系统研究

【作者】 徐慎敏；

【导师】 周国荣；

【作者基本信息】 中南大学 ， 控制科学与工程， 2011， 硕士

【摘要】 永磁同步电机(PMSM)具有体积小、效率高、结构简单等优点,在要求高控制精度和高可靠性的场合,比如航空航天、数控机床、雷达与各种军用武器跟随系统及机器人等方面获得了广泛的应用,在现代交流电机中也占有举足轻重的地位。论文首先对永磁同步电机结构及特点进行了分析,继而给出了永磁同步电机在不同坐标系下的数学模型；深入探讨了直接转矩控制在永磁同步电机上的应用理论基础,分析了电压矢量对电机电磁转矩和定子磁链的控制作用；在此基础上给出了永磁同步电机直接转矩控制原理结构框图。针对直接转矩控制所存在的转矩和定子磁链脉动问题,本文在分析空间矢量调制直接转矩控制和滑模变结构直接转矩控制的基础上,提出了基于分段调制策略的直接转矩控制,利用滑模变结构对系统参数变化和负载扰动不敏感、鲁棒性好、响应速度快的优点来克服电压模型磁链观测的缺陷。在此基础上,借助Matlab/Simulink工具,对所提出的控制策略进行仿真,得到了与理论分析一致的仿真实验结果,验证了理论的可行性。最后,设计了以DSP处理器为核心、整流器和智能功率模块为主电路的系统硬件平台,并给出了系统软件各模块的流程图。更多还原

【Abstract】 Permanent magnet synchronous motor (PMSM) is characterized by small volume, high efficiency, simple structure and so on and it has been widely used in fields which require high control accuracy and reliability, such as aerospace, digital control machine tools, radar and a variety of military weapon systems and robotics, it also occupies a pivotal position in modern AC motor.The structure and characteristics of PMSM are analyzed firstly in this paper, the mathematical models of PMSM in different coordinate systems are given. The paper deeply studies theories of direct torque control (DTC) based on PMSM, analyses the control actions of voltage vectors to electromagnetic torque and motor flux. According to the mentioned theories, the paper gives the block diagram of direct torque control principle for PMSM.To solve the problems of the torque and the flux ripples in the DTC system, this paper presents a direct torque control scheme based on segmental modulation method, after analyzing DTC strategies using space vector modulation and sliding mode. The scheme takes advantages of the features of sliding mode that it is insensitive to system parameter variations and load disturbances, as well as good robustness and fast response, to overcome defects of flux observation based on voltage model. The proposed control strategy is simulated by tools of Matlab and Simulink, and the simulation results agree with theoretical analysis, verifying that the theory is correct.Finally, the system hardware design, which uses DSP as control core, rectifier and intelligent power module as main circuit, is given, so do the flow charts of each module of system software.更多还原