Deadbeat current control for open-end winding induction motor using current prediction with two different time-horizons

The combination of deadbeat controller and open-end winding topology is effective for improving the response of current control of induction motor drive system. A deadbeat current controller achieves high gain by compensating the delay element of digital controller with current prediction and excluding it from the control loop. The response of a deadbeat current controller depends on the duration of the sampling period of the digital controller. Quarter carrier sampling which measures current and updates the reference voltage at the top, bottom and middle point of the carrier is applicable to the current control of the open-end winding because the winding of each phase is fed by an H-bridge. This method reduces the sampling period by half compared to the conventional half carrier sampling. However, the quarter carrier sampling for H-bridge has a problem that the current measurement at the middle point of the carrier is susceptible to switching noise. In this paper, a new deadbeat current controller for an open-end winding induction motor is proposed. The proposed method also updates the reference voltage every quarter carrier period but measures current only at the peak of the carrier. At the middle point of the carrier, predicted current with two-sample time-horizon is used for the calculation of the reference voltage instead of the measured current which is not available.