Optimization of starting performance of thyristorized static switch fed three phase induction motor

This paper establishes the fact that optimum value of firing angle for the thyristorized voltage controller fed induction motor at starting depends on motor parameters. Identically rated motors with different parameter values are considered for the work. Extensive simulations are carried out to obtain the optimum firing angle of the voltage controller, which gives zero negative torque pulsations with minimum acceleration time. Other factors under considerations are peak positive electromagnetic torque pulsations, peak starting current, nature of the voltage and current waveforms at steady state and current ripple. Results show that, though the machines have same rating, their optimum firing angles are different due to the difference in parameters.