Cost effective PAM inverter for 42V hybrid electric vehicles (HEV)

In the conventional motor drive system, as sixswitch inverter topology with dc battery for the 42V HEV, the current and torque ripples become high during start-up and low speed region. In this paper, to overcome these shortcomings, a novel PAM inverter is proposed, which consists of a two-switch buck-boost converter and a four-switch inverter. In addition, as the current and torque ripples are generated by a voltage difference between back EMF and battery voltage, these ripples could be reduced according to the controlled dc-link voltage according to the motor speed.