SiC二极管在高频大功率电流型逆变器中的应用

Application of SiC diode in high frequency and high power current inverter

针对电流型逆变器桥臂并联扩容时开关损耗较大的问题,对SiC肖特基二极管和Si快恢复二极管的正反向恢复特性、MOSFET并联均流特性以及容性状态下电流型逆变器工作过程进行了研究。提出了在电流型逆变器中用SiC肖特基二极管代替Si快恢复二极管以实现保持逆变器良好并联均流效果的同时降低逆变器损耗。分别搭建了基于Si快恢复二极管和SiC肖特基二极管的电流型逆变器实验平台以对比验证SiC肖特基二极管在系统扩容应用中实际效果。研究结果表明,在电流型逆变器中使用SiC肖特基二极管可以极大地降低逆变器损耗同时保持逆变器良好的均流效果,提高逆变器效率。

Aiming at the problem that the switching loss of the current-mode inverter was larger when the bridge arm was expanded in paral-lel. The forward and reverse recovery characteristics of SiC Schottky diodes and Si fast recovery diodes, the parallel current sharing of MOS-FET and the working process of current inverters were studied respectively. Then the replacement of Si fast recovery diode with SiC Schottky diode in the inverter to maintain good inverter parallel current sharing effect while reducing inverter losses was proposed. At last current-based inverter experimental platforms based on Si fast recovery diode and SiC Schottky diode were built respectively to verify the actual per-formance of SiC Schottky diode in system expansion. The results indicate that the use of SiC Schottky diodes in current-mode inverters can achieve good parallel current sharing effect while greatly reducing inverter losses and improve inverter efficiency.