Online Temperature Identification Strategy for Position Sensorless PMSM Drives With Position Error Adaptive Compensation

For the position sensorless permanent magnet synchronous motor (PMSM) drive system, the online identification of temperature is of great significance for safe operation. Generally, the motor temperature can be obtained directly from the stator resistance, the identification of which is, however, affected by the position estimation error of sensorless control. In order to deal with this problem, a stator temperature identification method for the interior PMSM is proposed with the position error adaptive compensation. The influence of position error on the stator resistance and temperature identification is analyzed and then compensated based on the minimum current vector online tracking (MCVOT) scheme for improving the identification precision. For further improving the accuracy and the convergence rate of MCVOT, a current vector angle tracking strategy based on the adaptive variable tracking step value is adopted in the rotating reference frame. The validity of the proposed method is verified on two experimental platforms.