Speed sensorless based on high frequency signal injection on bearingless synchronous reluctance motor

To reduce the cost of speed sensor of the bearingless synchronous reluctance motor and improve its practicability, a novel rotor speed estimation scheme using fluctuating high frequency voltage signal injection method is proposed. Based on motor space-saliency effect, the rotor speed can be observed simultaneously by injecting fluctuating high frequency voltage signal into torque winding. The simulation system is built by Matlab simulation software, Simulation results demonstrates that proposed method is capable of precisely estimating rotor position/speed, the bearingless synchronous reluctance motor can achieve stable sensorless suspension operation, and has good dynamic and static performance.