As the electric vehicle (EV) is becoming more and more popular, there exists an increasing need for more efficient charging facilities for both on-board and off-board chargers. High power density on-board charger can help reduce the weight of the vehicle and leading to higher miles per kilo-watt-hour (kwh). What is more, EV with tens of kilo-watt-hour battery is a perfect energy storage unit with mobility. Hence, in the next generation modern home-based microgrid system, EV can play multiple roles beyond transportation. For example, EV can send active power back to the grid, which can help reduce the power grid burden during peak hour. EV can also improve the distribution power grid quality by sending reactive (either inductive or capacitive) power to the grid especially where the heavy unbalanced load is connected. The power flow interaction between the vehicle is often recognized as G2V (Grid to vehicle or charging mode) or V2G (vehicle to grid). Not only does EV can help stabilize the grid, but also it can benefit the home appliance by providing robust AC (single-phase or three-phase) or DC voltage output for various loads whenever the mainline is not available. However, these application scenarios would not be feasible if there is no such universal power converter to facilitate the power flow. A modular and universal power converter is of great need to achieve this goal. Hardware design flexibility and scalability are very important which allows configurations into different ways to accomplish various functions mentioned above. Hence, in this thesis, a hardware prototype with the mentioned property is built to prove the idea and solve the challenges of integrating all function in a single unit. The wide bandgap power device is used due to their excellence in the reduction of switching and conduction losses. Robust gate drive design with protection feature is explained and verified with experiments results. Galvanic isolation is required in such a converter and implemented by an isolation transformer. The nanocrystalline core material is selected to construct the isolation transformer in this prototype since it has higher saturation flux density and relatively low core losses at high frequency. Optimization algorithm for low conduction loss under variable operating modes is proposed. A generalized transformer design procedure is also discussed and verified with experimental results. To realize these multiple functions, sensors and digital signal processors are used to control this converter. Detailed control strategy for each application scenario has been analyzed and verified with simulation or experimental results.
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