A direct self-control system of induction motor with resonant DC link

The direct self-control technique is a high performance method of an AC drive system. But the limit of the switching-frequency of the invertor in a direct self-control system is one of the important causes in that the improving accuracy of regulating speed in the DSC system is restricted, and the zero-switching or resonant inverting technique is one of the hot points in the domain of power electronics, because considerable reduction of the switching loss and great increase of the switching frequency should be possible. In this paper, the possibility that zero-switching technique should be used in a direct self-control system of an induction motor has been studied. A block diagram of resonant DC link direct self-control system for an induction motor has been proposed, and some important design formulas are presented. Computer simulation is performed and the result shows it to be feasible