A novel control method for permanent magnetism synchronous motor direct torque control system

Based on analysing the factors that cause 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 presents a novel control system which directly controls 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 is simple and easy to implement. The simulation results indicate static and dynamic performance of the new system is improved and torque ripple is decreased, simultaneously still retains the better control performance and higher efficiency than the typical direct torque control system.