SiC MOSFET特性及其应用的关键技术分析

SiC MOSFET(silicon carbide metal-oxide-semiconductor field-effect transistor)以其优越的特性受到国内外学者的广泛关注,采用SiC器件的变换器能够采用高的开关频率、适应高温工作,实现高的功率密度,在一些应用场合能够代替Si基高频开关器件而显著提高电能变换装置的性能。然而,SiC器件与Si器件存在较大的差异,在实际应用中直接替换使用会存在诸多的问题,例如提高工作频率后产生的桥臂串扰、电磁干扰EMI(electromagnetic interference)等问题。目前已有大量关于SiC MOSFET应用研究的文献,但大部分都是针对SiC MOSFET应用中个别问题的研究,尚缺少对SiC MOSFET应用研究成果的系统性归纳与总结的文献。首先基于对SiC MOSFET与Si MOSFET/IGBT(insulated gate bipolar transistor)的静态、动态特性的对比,总结出SiC MOSFET在实际应用中需要关注的重点特性;然后从SiC MOSFET建模、驱动电路设计、EMI抑制以及拓扑与控制方式的选择等方面对已有的研究成果进行归纳与评述;最后指出了SiC MOSFET在应用中所需要研究解决的关键问题。

Analysis on Characteristics of SiC MOSFET and Key Techniques of Its Applications

SiC MOSFET attracts widespread attention of scholars with its superior characteristics. The performances of power converters, such as switching speed, junction operating temperature and power density can be significantly improved with the replacement of Si-based high frequency switching devices in some applications. However, because of the many differences between SiC and Si devices, direct replacements may cause many problems in practical applications such as the serious crosstalk and EMI problems with the increasing of operating frequency. Many related studies were revealed, but the systematical summary of the existing work has not been seen yet so that the focus of the future work is unclear. Based on the static and dynamic characteristics comparisons between SiC MOSFET and Si MOSFET/IGBT, this paper aims to review the relevant research in the following aspects: SiC MOSFET modeling, gate driver design, EMI suppression and selections of topology and control scheme. The key techniques of SiC MOSFET applications are given.