A Novel Multilevel EV Charging Station Based on the Parallel Hybrid Converter and Dual Active Bridge

A novel multilevel electric vehicle-(EV) charging station based on the parallel hybrid converter (PHC) and dual active bridge (DAB) converter (PHC-DAB) is proposed. The PHC is popular at medium-voltage (MV) since, it requires lesser number of switching devices, energy storage elements while manifesting smaller footprint and cost. The MVDC link of the PHC transfers controlled active power to its individual sub-modules (SMs) in order to charge the EVs as per requirement while the PHC can be commanded to provide active and reactive power support to the three-phase grid in all four quadrants. Furthermore, the dynamics of operation at the interfacing point between PHC and DAB is analyzed. A detailed mathematical analysis is done to derive the power dependency of SMs of PHC on ac grid and MVDC current, duty cycle of SM and the operating power factor. The working of proposed PHC-DAB converter is verified with simulation and experimental results.