Modeling and Control of a Resonant Dual Active Bridge With a Tuned CLLC Network

This paper proposes a linear state-space model for a phase-controlled resonant dual active bridge with a tuned capacitor-inductor-inductor-capacitor network. The proposed model is useful for fast simulation and for the estimation of state variables under large signal variation. The model is also useful for control design because the slow changing dynamics of the dq variables are relatively easy to control. Using the proposed model, a decoupled control scheme was designed which allows for the control of the high frequency link currents while also improving the soft switching range of the converter. Using steady-state relationships between state variables and the system inputs, the controller was simplified from three proportional integral (PI) controllers to a single PI controller. The controller was implemented on a low cost digital signal processor and verified experimentally. The experimental and simulation results showed the proposed model's usefulness for control design and fast simulation.