Abstract
Dual active bridge (DAB) converters are extensively used in isolated bidirectional DC–DC power conversion systems for EV charging applications. In DAB converters, inductor current ripple remains a major challenge, leading to conduction losses, thermal stress, and reduced reliability specially during light loaded constant voltage (CV) charging of battery. In this article, a finite control set model predictive control (FCS-MPC) is proposed for inductor current ripple suppression. In comparison with the existing methods where rms inductor current is reduced without considering ripple reduction, the proposed FCS-MPC develops a new discrete-time inductor current prediction model using the leakage inductance and parasitic effects for accurate inductor current estimation. Moreover, the weighting factor of the proposed FCS-MPC is optimized for ripple current reduction using Newton–Raphson optimization method. A SiC–Si asymmetric bridge configuration is employed to ensure real-time execution, with the high-frequency SiC stage executing the predictive control and the low-frequency Si stage reducing switching losses. Compared with proportional–integral (PI)-based single-phase-shift control, the proposed strategy reduces inductor current ripple by 10%–15% and total harmonics distortion (THD) by 2%–8% under light-load operation. Simulation and experimental results are shown to validate the inductor current ripple suppression capability of the proposed method.