High Power Dual Active Bridge Converter in Wide Voltage Range Application

Dual Active (Full) Bridge (DAB), has the advantages of wide voltage operation range, zero voltage switching, and easier bidirectional control. However, the traditional single phase shift (SPS) control has the circulating current problem which will cause high conduction and switching loss, especially under different transfer ratios between input and output operating conditions. Many modulation methods are proposed to solve the aforementioned problem. This paper adopts the dual phase shift (DPS) with a minimum peak current control algorithm to reduce the conduction and switching loss. Eventually, a 10 kW DC-DC converter is implemented with a digital controller and has been evaluated. The output voltage range of this converter is from 400 V to 500 V and input voltage is 750 V. According to the test result, the peak efficiency is up to 97.6% when the output voltage is 500 V, 60% load, moreover, when converter operating at 400 V output voltage and 10% load, the efficiency is 94%.