Design and experimental verification of on-board charger for electric vehicle
In this paper, an on-board charger for electric vehicle, with two-stage power converter, is designed. Firstly, a single-phase Boost-APFC (Active Power Factor Correction) circuit controlled by a one-cycle controller is designed as the front state converter. Compared to the traditional APFC circuit, the One-cycle controller is constructed without considering the multiplier and AC line voltage sensing circuits, which is suitable for APFC system. Moreover, the one cycle controlled Boost-APFC converter has strong ability to reject the input voltage disturbance. After that, the second stage converter is an improved phase-shifted full-bridge ZVZCS (Zero Voltage Zero Current Switching) power converter, wherein the secondary side of the auxiliary circuit is consisted of two diodes and a clamp capacitor. The clamp capacitor is charged on transfer mode and discharged on free-wheeling mode. By achieving the ZCS on the lagging leg, the voltage stress on the secondary side of the rectifier bridge is reduced. Based on the effective duty cycle approach of small signal model on Buck converter, a new small signal model has been built, which provides a theoretical basis for closed-loop control circuit analysis and design. Finally, a 1Kw prototype, with 120V (AC) input and 200V output, is built. IR1153S and UCC3895 were used as the control chips, and the switching frequency is 22 kHz. Moreover, the prototype has been achieved a peak efficiency of 92% at a full load.