Low torque ripples are needed by the industrial loads. Torque ripples are produced in motor due to the commutation. The motor input current thus distorting from the ideal current waveform shape due to the motor inductance. So in one particular interval one phase current is decaying slowly and another phase current is increasing slowly. Due to this, the commutation ripples exists in the torque. Because of the brushless dc motor input supply current commutate at every 60 degrees interval, the magnetic field wave developing and revolving unequally. At every 60 degree the rotor position is observed, so the torque is not constant, ripples are existing in the torque curve which is undesirable. Hysteresis current controller and PWM control simulation models are given to reduce this type of torque ripples. The torque ripple reduction due to Hysteresis and PWM control methods are presented.
MATLAB/Simulink model, modelling of BLDCM, torque ripple, hysteresis, PWM
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