There are problems of low precision, poor stability and algorithm complexity in the sensorless control of permanent magnet linear synchronous motor (PMLSM) at standstill and low speed. In order to solve these problems, an improved sensorless control method based on pulsating high frequency injection is proposed. Based on the preliminary position estimation using saturation saliency of PMLSM, the method of special position correction and magnetic pole judgment is proposed. In this way, more accurate mover position is obtained and the sensorless operation of PMLSM at standstill and low speed is realized. On this basis, the model of PMLSM sensorless control is established by Simulink, and a prototype experimental platform is built for experimental verification. The simulation and experimental results show that the proposed method can accurately and quickly detect the initial position of PMLSM mover and the mover position at low speed, ensure the smooth starting and running of the motor, and have good position estimation accuracy and dynamic performance.