A NEW INSTANTANEOUS TORQUE CONTROL OF PM SYNCHRONOUS MOTOR FOR HIGH-PERFORMANCE DIRECT-DRIVE APPLICATIONS

A new instantaneous torque-control strategy is presented for high-perf ormance control of a permanent magnet (PM) synchronous motor, In order to deal,vith the torque pulsating problem of a PM synchronous motor i n a low-speed region, new torque estimation and control techniques are proposed, The linkage flux of a PM synchronous motor is estimated usi ng a model reference adaptive system technique, and the developed torq ue is instantaneously controlled by the proposed torque controller com bining a variable structure control (VSC) with a space-vector pulse-wi dth modulation (PWM), The proposed control provides the advantage of r educing the torque pulsation caused by the nonsinusoidal flux distribu tion. This control strategy is applied to the high-torque PM synchrono us motor drive system for direct-drive applications and implemented by using a software of the digital signal processor (DSP) TMS320C30, The simulations and experiments are carried out for this system, and the results well demonstrate the effectiveness of the proposed control.