Robust speed sensorless control of PMSM

This paper presents a speed sensorless non-salient permanent magnet synchronous motor (PMSM) sliding mode control algorithm. The key idea is to integrate the benefits of the variable structure system control design and the event-driven sequential control structures to raise the system performance and control efficiency. The operation at low speed is improved by reducing the disturbance impact. The estimation angle error at zero speed is limited by injecting the DC current that compensates the unknown load torque and enables operation at zero speed. The VSS speed sensorless control of PMSM is implemented on a DSP/FPGA system, and verified experimentally.