Sensorless control technology of permanent magnet synchronous motor (PMSM) has been more and more popular. High-frequency (HF) rotating voltage injection is convenient to extract the HF current containing rotor position error information when PMSM is running at low speed. In this paper, the HF rotating voltage signal injection is used in order to extract the rotor position and speed information. Related experiments are carried out to verify the reliability of proposed method.