A two-degrees-of-freedom current control scheme for deadtime compensation

Abstract

A current controller having an inverse dynamic model and a proportional-integral (PI) controller has been proposed with the aim of compensating the effects of deadtime, The proposed control scheme, having two degrees of freedom, can be used for compensating the effects of disturbance without degrading tracking performance. To be specific, the disturbance-rejection property is enhanced by increasing the gains of the PI controller, but the PI gain does not affect the transfer function between the current command and its output. By nature, it is robust to the parameter mismatch error between the model and the plant, since the mismatch error can be counted as another disturbance. With the experimental results, we have shown the superiority of the proposed method in suppressing the current distortion caused by deadtime.