Effects of Parasitic Elements in High Frequency GaN-based DC-DC Converters for Electric Vehicle Applications

This paper analyzes half-bridge DC-DC buck converter topology operating in buck mode using Gallium Nitride (GaN) transistors for Electric Vehicles (EVs) application. The LTspice-based simulation model is developed for the buck converter with parasitic elements to evaluate performance efficiency for varying load. The impact of parasitic passives (resistance, inductance, and capacitance) such as ringing by parasitic inductance on GaN transistor operation are also explored. Effects on performance efficiency has been carried out with and without including the parasitic elements in the simulations to evaluate the importance of modeling with parasitics. Performance efficiency evaluation results are also bench-marked against the results of the EPC 9162 demonstration board working as a bi-directional buck converter.