In order to realize the self-sensing detection of rotor radial displacement of bearingless induction motor,a radial displacement estimation method based on high frequency signal injection method is studied in this paper. According to the mutual inductance variation between the torque winding and suspension winding,by injecting fluctuating high frequency voltage signal into torque winding,the induced high frequency current signal in suspension winding is detected,and the radial displacement signal of the rot...