Control techniques for improved low speed performance of a PM synchronous motor

The permanent magnet synchronous motor has several desirable features for high performance adjustable-speed operation. This paper describes two control techniques to enhance the performance of a surface PM motor at low speed (1 rev/s). The first technique is an internal model control scheme improving the performance of the acceleration corrector. The second technique consists in using a robust model-matching H_∞ controller which is appealing when the parameters of the system are submitted to variations