Based on analysing the factors that caused torque ripple and analysing the nonzero demagnetism/in magnetism component in stator current for the typical direct torque control system of the permanent magnet synchronous motor, this paper presented a novel control system which directly controled the magnetizing component of the stator current with two-level bang-bang controller. The improvement eliminated the component which in the stator current did not hope, enhanced the exchange transmission system efficiency. It was simple and easy to implement. The simulation results indicated static and dyna...