An Optimized DPS Control Strategy for LCL Resonant Dual Active Bridge Converter for Wide Voltage Conversion Ratio

Abstract

This article presents an improved DPS (IDPS) control strategy for LCL resonant dual active bridge converter. Due to the LCL resonant tank, the converter's working modes are analyzed by using the Fourier transform. According to the fundamental harmonics of the key waveforms, the condition of zero-voltage switching (ZVS) in different working modes is derived. The relationship between the conduction loss and load power is analyzed. To achieve ZVS with low conduction loss and seamless transitions between the forward and reverse power flow, an IDPS modulation scheme is proposed. The control strategy can cover all the load power. The conduction loss in the IDPS is compared with the enhanced DPS, which illustrates the lower conduction loss. Finally, a 1-kW experimental prototype has been built to verify the effectiveness of the IDPS control strategy.