DC/DC converter control for voltage ripple reduction in electric vehicles

Switching in power electronics can induce significant harmonics in the central dc-link voltage of electric vehicles and thereby necessitates appropriate filtering through bulky dc-link capacitors. However, low frequency harmonics might also be suppressed by advanced control of DC/DC converters usually employed in drive trains with more than a single energy storage device. In this work, a model based feed forward control scheme for suppression of voltage harmonics induced by six-step operation of the motor inverter is presented. By computation of the inverter input current spectrum, the controller achieves significant reduction of the dc-link voltage ripple compared to traditional control schemes.