Dual Active Bridge (DAB) converters have emerged as a leading solution for industrial applications that require high efficiency and bidirectional power transfer with isolation. The Triple-Phase-Shift (TPS) modulation scheme enables flexibility to enhance efficiency by choosing the operating point that minimizes power losses. This paper presents a novel, simplified methodology for reducing conduction losses in DAB converters using polynomial-based techniques. The operation of the DAB converter under TPS modulation is analyzed, and the corresponding modeling equations are derived. The proposed optimization method is described and validated through simulations in various design scenarios. The results demonstrate the existence of a set of three polynomials that effectively minimize the rms current based on the load conditions and the voltage ratio. Preliminary findings show that these polynomials will remain nearly constant across different converter designs, provided the output-to-input voltage ratio is the same.

Super-Capacitor (SC) modules are crucial in Hybrid Energy Storage Systems (HESS) designed for robotics. This paper details their implementation, with a significant emphasis on the synergy between SCs and batteries to address demanding power requirements. It focuses on SC aging resulting from high temperatures. A systematic approach to voltage selection, encompassing optimal operating parameters, durability projections, and energy efficiency is presented. The equilibrium between power demands and SC capacities is achieved through considerations of intermediate voltage, energy fluctuations, and filtering techniques. The significance of module capacitance is highlighted, employing data-driven techniques to select optimal cell capacitance across various scenarios. In summary, this data-driven approach seamlessly integrates theory, empirical measurements, and meticulous design, effectively engineering SC modules within HESS for cutting-edge robotic applications.

In this paper, the design of a modular high-power transformer for constant gain LLC converter used in 2-stage Fast EV charger is investigated. Two modular approaches are compared, input-parallel-output-parallel (IPOP) and input-series-output-parallel (ISOP) transformers with stacked cores. The Pareto optimization of total power losses and volume is applied to evaluate different modular designs. The design method based on Ansys PExprt software tool is developed and explained. Finally, the selected design is validated by 3D FEA thermal simulation in ICEPAK.

In this publication, specifications of a modular fast EV charging converter are selected based on standards and the state-of-the-art. According to these specifications, a 2-stage cascaded conversion approach is proposed, with separated isolation and charging regulation stage. This enables the design optimization of the each stage for different functionality. Furthermore, a partial power (PP) processing is implemented in the regulation stage to improve the efficiency. Two different 2-stage isolated topologies using PP structure are proposed, employing either 2 or 3 voltage levels. The converters use SiC or Si devices, depending on the voltage stress on the devices for each topology. Additionally, the gain of the PP converter of the regulation stage and the turns ratio of the transformer are analyzed and optimized to reduce the RMS of inductors and switches, as well as the inductor peak energy. The design calculations are done considering full-ZVS condition on all switches, except for the balancer switches with applied ZCS instead. Finally, the two topologies are compared and discussed.