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-performance control of a permanent magnet (PM) synchronous motor, In order to deal,vith the torque pulsating problem of a PM synchronous motor in a low-speed region, new torque estimation and control techniques are proposed, The linkage flux of a PM synchronous motor is estimated using a model reference adaptive system technique, and the developed torque is instantaneously controlled by the proposed torque controller combining a variable structure control (VSC) with a space-vector pulse-width modulation (PWM), The proposed control provides the advantage of reducing the torque pulsation caused by the nonsinusoidal flux distribution. This control strategy is applied to the high-torque PM synchronous 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.