Speed sensorless induction motor driver system using a novel motor sensor coil

Due to these disadvantages of pre-existing speed sensorless induction motor driver systems, a novel sensorless induction motor driver system using a novel motor sensor winding. The proposed sensor winding is installed in a slot of the induction motor for measuring the induction voltage of air-gap magnetic field. By digital processing system, the value of the rotor current in motor T-type equivalent circuit can be calculated. According to the values of the induction voltage and the rotor current, the slip ratio and the motor speed can be calculated. The advantage of the proposed sensorless induction motor driver system is that the accuracy of the proposed digital processing system only relies on the motor rotor resistance parameter and needs a relatively simple hardware/software setup.