Design and Analysis of High Power Bidirectional Resonant Converters for 800-V Battery Charging Applications

This paper presents the design and analysis of a high power bidirectional resonant converter suitable for 800-V battery charging applications. The topology used is a bidirectional CLLC resonant converter which is an isolated DCDC converter topology typically preferred in high voltage battery charging applications. A 22- kW bidirectional CLLC resonant converter and its resonant tank parameters are designed with the identification of switching frequency range to regulate the battery voltage in the range of 550-850 V from a nominal DC bus voltage of 800 V. The analysis of bidirectional operation with switching waveforms and efficiency evaluation are carried out in forward and backward modes of power transfer and simulation results are presented.