Modeling and Control Gain Design Method for Dual Active Bridge Converter with Dual-Phase-Shift Modulation

Abstract

The Dual Active Bridge (DAB) converter offers several advantages, including high power conversion efficiency and improved safety by providing galvanic isolation between the input and output through the use of a high-frequency transformer and H-bridge circuits on both the primary and secondary sides. Although numerous studies have explored DAB converters, research on transfer function modeling under Dual Phase Shift (DPS) modulation and its correlation with controller gain design based on converter parameters remains limited. This paper proposes a modeling approach for a DAB converter with DPS modulation and presents a parameter-based gain design method for a voltage-current double-loop controller. The dynamic characteristics of the DAB converter are derived using generalized average modeling (GAM) based on Fourier transformation. The derived transfer function is simplified based on the locations of its poles and zeros. Based on this simplification, a systematic procedure for proportional-integral (PI) controller gain design is formulated for both output voltage and current regulation. The validity of the simplified transfer functions is verified through Bode plot analysis. The validity and effectiveness of the proposed control gain design method are verified through a hardware-in-the-loop simulation (HILS) capable of emulating a virtual DAB converter. Through this experiment, both the steady-state and transient responses of the virtually implemented DPS-modulated DAB converter are evaluated. The results validate the effectiveness of the proposed approach in achieving stable DPS modulation and control in DAB converters.