Determination of Optimal Associated Discrete Circuit Switch Model Parameters for Real-Time Simulation of Dual-Active Bridge Converters

Real-time simulation of a Dual-Active Bridge (DAB) converter based on the Associated Discrete Circuit (ADC) switch model is considered in this work. The ADC switch model allows for efficient simulation as its topology is fixed regardless of the switch state. The main disadvantages of the ADC-based simulation of power electronics converters are virtual power losses and artificial oscillations following switching events, which might significantly deteriorate simulation fidelity. A suitable parameter for constant conductance of the ADC switch model should be selected to minimize virtual power losses and artificial oscillations. However, a constant conductance parameter that minimizes virtual power losses might result in a low degree of simulation fidelity in terms of transformer current for the case of the DAB converter. This paper demonstrates with a numerical example the inconsistency of the objectives when selecting an optimal constant conductance parameter for simulation of the DAB converter. To address the challenge, a Loss Compensation Algorithm (LCA) is utilized to minimize virtual power losses, while a method to determine a suitable ADC switch model parameter that ensures specified accuracy of the transformer current is derived analytically. Time-domain simulation results of DAB converter are provided for validation of the proposed method.