Improved techniques of restrained search predictive control for multiphase drives

Predictive control techniques have been recently applied with success to electrical drives. The additional degrees of freedom in multiphase drives make the real-time implementation difficult if optimal solutions are sought due to the increased number of iterations. Recent research works propose a restrained search predictive control (RSPC) that restricts the available voltage source inverter (VSI) switching states according to predefined constraints. The on-line implementation is favoured at the expenses of achieving suboptimal solutions. This paper presents a new RSPC technique that allows more switching states at each sampling time to obtain improved performance. The advantages of the proposed method are verified by simulation both in steady and transient states.