A digital controlled DC-DC converter for electric vehicle applications

This paper presents a digital controlled DC-DC converter for electric vehicle applications. The proposed system converts high battery voltage of electric vehicle into low voltage for vehicle's electronic equipments. The power stage of the proposed converter is a phase-shifted ZVS (zero-voltage-switching) full-bridge DC-DC converter, the current doubler and synchronous rectifier circuits are used at the output of the converter for higher efficiency of the converter. Regarding the control of the converter, only one one-chip PIC microcomputer is used for the feedback control of output power and driving all switches. Therefore, the simplest digital control block for this DC-DC converter is established. To verify the performance of the proposed converter, a 1.5kW prototype converter is built and tested. From the experiment, it is obtained the maximum efficiency of 95% at low line and half load.