定子电阻是永磁同步电机直接转矩控制(简称DTC)模型估算中用到的唯一参数.传统DTC系统估算模型中,定子电阻的取值往往是固定不变的.而电机在实际的运行中,定子电阻是随温度及周围环境的变化而,变化,这样就导致了电机低速性能差的缺陷.本文提出了一种基于PI控制器的定子电阻补偿器,将磁链误差和转矩误差分别通过两个PI控制器,它们的输出按照一定的比例混合后作为电阻补偿值.通过Matlab/Simulink环境下的仿真,电机的低速转矩脉动明显降低,说明了该设计的有效性和可行性.%Stator resistance is the only parameter used in permanent magnet synchronous motor DTC system. The stator resistance value is usually constant in conventional DTC system estimation model. However, the stator resistance always changes with the environment such as temperature while the motor is running, which leading to the bad performance at low velocity. A stator resistance compensator based on PI controller is proposed in the paper. The flux error and torque error pass two PI controllers, whose outputs are mixed according to certain proportion. Then the result is used as stator resistance compensation value. Through the simulation in Matlab/Simulink environment, the torque ripple at low velocity of the motor is markedly reduced, showing the validity and feasibility of the design.
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