Control strategies for a high frequency DC-DC converter for electrified vehicles

In this paper, three control strategies for a wide band-gap bidirectional DC-DC converter (BDC) are introduced and combined to improve the vehicle traction system performance. A feed-forward control algorithm is proposed to reduce the voltage ripple of DC-link capacitor located between the BDC and traction inverter. Through voltage control of the BDC, both three-phase short and uncontrolled generator operation may be avoided for an improved fault tolerant response of the interior permanent magnet (IPM) motor drive system. With coordinated control of the converter output voltage, the traction system efficiency can be improved, when compared with constant DC bus voltage operation. The proposed control algorithms are validated through simulation and experiment.