A General Peak Current Limiting Strategy for Start-up and Fault-Ride-Through in Dual Active Bridge Converters

This article presents a general peak-current limiting strategy for Dual Active Bridge (DAB) converters under Triple Phase Shift (TPS) control, which can achieve both Fault-Ride-Through (FRT) capability and soft start. DAB converters often encounter overcurrent conditions during start-up, overload, or short circuit. The proposed method addresses these challenges by integrating peak current limitation directly into TPS control, without adding additional control complexity. This strategy allows the maximum phase shift angle to be constrained according to a predefined peak current threshold, thereby limiting the peak current. This constraint improves the fault tolerance of the converter and enhances system stability. Analytical derivations of the peak current limiting strategy are provided, and numerical analysis is conducted to verify its accuracy. Experimental results verify the effectiveness of the proposed strategy under both start-up and overload. The strategy offers a simple and effective solution to protect the DAB converter from overcurrent.