Study of dead-time compensation on direct torque control of ALA rotor motor

Space-vector pulse width modulation (SVPWM) method have been wildly developed in direct torque control and vector control. The SVPWM is an excellent control strategy, but the relation between reference voltage and actual output voltage is nonlinear due to the dead time effect and the voltage drop of power devices. The distortion of voltage invokes serious problems such as current waveform distortion and deterioration of the systems. An improved method which reduces the distortion of voltage and current in axially laminated anisotropic (ALA) rotor motor direct torque control (DTC) system is presented. It compensated three-phase voltages in terms of current directions. The method can be implemented with software without any extra hardware. The experiment results verify this method has a good compensation effect.