永磁同步电机无位置传感器控制采用传统滑模观测器法来获取转子位置，由于滑模抖振严重、估计反电势中含有低次谐波干扰及传统锁相环在电机反转时有位置误差等因素，影响转子位置估计精度。通过设计自适应滑模观测器和改进锁相环来解决上述问题。首先采用非奇异快速终端滑模面及改进指数趋近律来降低滑模抖振。其次对传统锁相环鉴相器进行改进并在环路滤波器中引入二阶广义积分器，不仅使电机正反转时能准确提取转子位置信息，还能滤除估计反电势中的低次谐波。仿真结果表明所设计的算法能减小滑模抖振、降低位置跟踪延迟时间及提高位置观测精度。

The traditional sliding mode observer method is used to obtain the rotor position in the position sensor control of the permanent magnet synchronous motor. The accuracy of rotor position estimation is affected by the factors such as the serious vibration of the sliding mode, the low harmonic interference contained in the estimated reverse potential and the position error of the conventional phase-locked loop when the motor is reversed. The above problems are solved by designing an adaptive sliding mode observer and improving the phase-locked loop. Firstly, a non-singular fast terminal sliding mode surface and an improved exponential approach law are adopted to reduce the sliding mode vibration. Secondly, the traditional phase-locked loop phase detector is improved and the second-order generalized integrator is introduced into the loop filter, which not only enables the accurate extraction of rotor position information when the motor is rotating forward and reversed, but also can filter out the low harmonics in the estimated reverse potential. The simulation results show that the effectiveness of the designed algorithm in reducing the sliding mode vibration, decreasing the delay time of position tracking, and improving the accuracy of position observation.