Super-twisting sensorless control of permanent magnet synchronous motors

In this paper a sensorless control scheme is presented for permanent magnet synchronous motors. Position and angular velocity are estimated on the basis of current measurements and voltage input, making use of a super-twisting sliding mode observer. The estimated angular velocity is used to track a reference velocity. The control scheme implements also an observer of the load torque. Simulations show that the proposed observer-based control scheme performs well, also in the case of low velocities.