Analysis of EMI and Efficiency of the GaN and Si MOSFET converters

摘要

The influence of the switching frequency of a GaN-based half-bridge converter on efficiency and spectrum of conductive electromagnetic interferences are investigated. It is established that for such converter the maximum efficiency achieved at a switching frequency of 500 kHz, while the minimum level of interference is at a switching frequency of 1 MHz. Thus, the switching frequency can be selected depending on the required output parameters of the converter. A comparative analysis of EMI for efficiency 0.93-0.94 of the half-bridge converters with GaN and Si transistors is performed. The level and spectrum of the EMI in the frequency range up to 30 MHz depends more on the switching frequency and PCB layouts. Based on this investigation, some recommendations were proposed.