高级检索

高压大功率SiC MOSFET短路故障快速保护方法

A Fast Short-circuit Protection Method for High-voltage and High-power SiC MOSFET

  • 摘要: 碳化硅(SiC)MOSFET短路耐受能力弱,因此对短路检测的快速性、可靠性提出了更高要求。现有SiC MOSFET短路检测主要基于单一电气量,且大多围绕低压小功率器件。随着电压和功率等级的提升,器件特性有所差异,直接套用以往设计难以实现高压大功率SiC MOSFET的可靠、快速保护。首先,探讨了几种常用的短路检测方法;其次,基于高压大功率SiC MOSFET器件特性,对比分析了不同短路检测方法的适用性,提出一种多电气量检测的先启动后加速式短路故障保护方法;最后,搭建了实验平台验证所提方法的可行性。结果表明,所提短路保护方法既实现了硬开关短路故障(HSF)和负载短路故障(FUL)的可靠识别,又兼顾了保护动作的快速性。

     

    Abstract: SiC MOSFET has weaker short-circuit tolerance, which requires higher demand on the rapidity and reliability of short-circuit protection. Most of the existing methods mainly adopt single electrical parameter, and are focused on low-voltage and low-power SiC MOSFET. However, with the increase of voltage and power level, device characteristics are significantly different, which makes it difficult to achieve fast and reliable protection for high-voltage and high-power SiC MOSFET by simply applying previous designs. Firstly, this paper conducts a detailed study on several common short-circuit detection methods. Secondly, based on the device characteristics of high-voltage and high-power SiC MOSFET, this paper deeply compares the applicability of different short-circuit detection methods. Next a new method based on multiple electrical parameters is proposed, which starts-up short-circuit fault protection firstly and then accelerates subsequently. Finally, an experimental platform is built to verify the feasibility of the proposed method. The results show that the proposed method not only realizes the reliable identification of hard switching faul (HSF) and fault under load (FUL), but also balances the response speed of short-circuit protection.

     

/

返回文章
返回