A method of speed sensorless control of direct-field-oriented induction motor operating at high efficiency with core loss consideration

The purpose of this work is to propose a speed sensorless control method for an induction motor operating at high efficiency and high response, which takes core loss into account, and to discuss the performance of the system. The induction motor is driven by a speed sensorless direct field-oriented control method with deadbeat flux level control using an adaptive rotor flux observer. On the basis of simulation and experimental results, the authors discuss that the proposed system can estimate motor speed, even if rotor flux is changed and core loss is considered.