Enhanced current control of high-speed PM machine drives through the use of flux controllers

This paper compares various types of current controllers, including a novel method based on flux control. A proportional integral (PI) control method is used initially, to control the current in a high-speed permanent-magnet synchronous machine. The performance of this simple PI loop is presented, Various improvements to the PI controller are investigated, and the change in performance examined. A new current control scheme based on a flux-linkage model of the machine is introduced. The performance of the model-based control is demonstrated and compared with the performance of the PI current controller. Factors affecting the accuracy of the model-based control are given. By incorporating these factors into the model, the performance of the flux controller is further enhanced.