An Improved Direct Torque Control for Torque Ripple Minimization of Four-Switch Brushless DC Motor with Trapezoidal Back-EMF

Direct torque control (DTC) can directly control the inverter states in order to reduce the torque and flux linkage errors within the prefixed band limits. In this paper a DTCtechnique is presented for brushless dc (BLDC) motors with nonsinusoidal back-EMF using four-switch inverter in the constant torque region. In addition, for torque ripple reductionin two phase conduction mode, a novel switching pattern incorporating with the voltage vector look-up table is designedin order to regulate the controllable phases torques (Tea , Teb). Simulation results approve that the proposed method reducestorque ripple in contrast with prior research

Keywords:

Brushless DC (BLDC) drives , direct torque control (DTC) , fast torque response , four-switch inverter , Torque ripple reduction