High frequency GaN HEMT modeling based on datasheet and measurement, and application to analysis of EMI from inverter

Abstract

Recently, the switching frequency of power devices in the power conversion system is gradually increasing for the purposes of weight reduction and miniaturization. In order to achieve these purposes, two different materials are mixed, or bonded each other. The Gallium-Nitride (GaN) High Electron-mobility Transistor (HEMT) utilizes the unique properties that occur in the interfaces formed by bonding two materials. However, the turn-on and turn-off times gradually decrease with the increasing trend of the switching frequency, thereby Electro-magnetic Interference (EMI) issues become increasingly problematic. Therefore, in order to analyze the EMI issues more accurately, this paper presents a circuit model for GaN HEMT, and applies it to an 80W class full-bridge inverter system to analyze the EMI problem. Finally, the proposed GaN HEMT model is verified by comparative analysis for the output result. In addition, i propose the method to analysis of EMI from the power conversion system through the equivalent circuit based on the proposed GaN HEMT model in this paper, instead of the method to analysis of EMI using the conventional Fourier transform or Laplace transform method.