Method and apparatus for reducing torque ripple in permanent magnet synchronous machines

摘要

It is presented a method for reducing torque ripple in a permanent magnet synchronous machine. The method comprises the steps of: measuring at least one value representing the operation of the magnet synchronous machine; estimating a back electromotive force using the measured value; and based on the estimated back electromotive force, estimating a stator current used in a feedback loop for estimating the back electromotive force. A corresponding apparatus and direct torque controller are also presented.