Output Voltage Correction for a Voltage Source Type Inverter of an Induction Motor Drive

A proposed voltage error correction method that uses a disturbance observer for various types of induction motor control was evaluated. The features of the proposed control method are: 1) control parameters are easily determined according to the motor model and the parameter sensitivity is robust, and 2) the proposed method can be applied for field-oriented vector control, speed sensor-less vector control, and V/f control of the induction motor by modification of a back electromotive force compensation term in the observer. The disturbance observer is designed to have fast response that is ten times faster than the current controller for vector control. The voltage error is efficiently corrected using the proposed method, and the current distortion can be reduced by approximately 1/3. The proposed method is validated on the basis of experimental results.