Optimal design of a soft switching inverter for control of an induction motor drive using scalar method

In this paper a new quasi-resonant DC link inverter is considered and this circuit is mathematically analyzed. Commutation time resonant circuit components are designed according to minimization of commutation times and power losses. Two new modulation methods are also proposed. After completion of circuit design, the whole motor drive is simulated. The major advantage of the proposed inverter is to control each inverter leg switch independently; as a result, the PWM switching control is much simpler than the conventional one. Finally, the designed inverter is used for feeding an induction motor drive to verify the effectiveness of the proposed design.