基于直流电压注入的永磁同步电机定子绕组温度在线估计

摘要

This paper proposes a new strategy to online estimate the stator winding temperature of permanent magnet synchronous motor. This new strategy doesn't need any temperature sensor and any change to the hardware of the motor drive system. By injecting a DC voltage signal to theα-axis voltage in vector control, the temperature of the stator winding can be estimated online based on the linear relationship between the temperature and resistance of stator winding. This method is especially suitable for high power motor, that is, injecting smaller signal can produce relatively large DC current on the phase winding, which reduces the difficulty in extracting the DC current component from AC phase current. Thus, the deviation of the temperature estimation can be effectively diminished. Three approaches of the DC voltage component to evaluate the stator resistance have been presented. The corresponding results have been analyzed and compared. Method one utilizes the injected DC signal to implement temperature estimation, hence the DC component can be obtained without phase voltage sampling and the related post-processing, which provides high estimation accuracy. Simulations and experiments have verified the effectiveness of this proposed strategy.%提出一种新的永磁同步电机定子绕组实时温度在线估计方法.该方法无需温度传感器,也无需改变电机驱动系统的硬件,仅需在矢量控制中向α轴注入直流电压信号,通过在线辨识定子电阻并结合金属材料温度与阻值的线性关系实现定子绕组实时温度的估计.该方法特别适用于大功率电机,注入较小的信号即可在相绕组上产生相对较大的直流电流,减小了在交流相电流中提取直流电流分量的难度和温度估计误差.提出三种定子电压直流分量的获取方法,并给出讨论分析和对比结果,其中直接采用所注入信号实现温度估计的方法,无需对相交流电压采样和后处理得到直流分量,估计精度较高.仿真和实验验证了所提方法的有效性.