SiC JMOS和SiC DMOS在Si/SiC混合器件单相逆变器中的应用研究

Application of SiC JMOS and SiC DMOS in Si/SiC Hybrid Switch Based Single-phase Inverter

Si IGBT与SiC MOSFET并联组成的Si/SiC混合器件(HyS)因在功率变换器中提供了一种成本与性能的优化折衷而受到广泛关注。其中,SiC MOSFET特性直接影响Si/SiC混合器件的性能,对基于不同类型SiCMOSFET的Si/SiC混合器件的特性差异分析极为必要。该文对比分析基于新型集成结势垒肖特基二极管(JBS)的SiCMOSFET(SiCJMOS)的Si/SiC混合器件(HySJ)和基于传统平面栅SiCMOSFET的传统Si/SiC混合器件(HySD)的特性差异。对比分析2种混合器件的导通特性与开关特性,结果表明,与HySD相比,HySJ具有更低的反向导通压降,更好的反向恢复性能和更小的开通损耗。建立适用于2种混合器件单相逆变器损耗模型,对比分析2种器件在逆变器应用中的损耗差异。设计基于2种混合器件的5kW单相逆变器样机,对比应用2种混合器件的变换器损耗、效率及器件结温。实验结果表明,在轻载条件下,与HySD方案相比,HySJ可以实现最大0.5%的峰值转换效率的提升。

The Si/SiC hybrid switch(HyS) concept of paralleling a main Si IGBT and an auxiliary SiC MOSFET offers an improved cost/performance tradeoff in power converters. The characteristics of the SiC MOSFET strongly affect the performance of the hybrid switch. It is necessary to analyze the characteristics of the hybrid switch based on different types of SiC MOSFETs. The HySJ based on the junction barrier controlled Schottky rectifier integrated silicon carbide MOSFET(SiC JMOS) and the HySD based on the conventional SiC MOSFET were comprehensively compared and studied. The results show that the HySJ has lower reverse conduction voltage drop, better reverse recovery performance and smaller turn-on switching losses than the HySD solution. A single-phase inverter loss model for hybrid devices was established, and the loss difference between these two solutions in the inverter application was compared and analyzed. A prototype of a 5 kW single-phase inverter based on two hybrid devices was built. The experimental results show that HySJ can achieve 0.5% improvement of the peak conversion efficiency compared to the HyS_D solution under light load condition.