SiC固态功率控制器关断电压尖峰抑制方法

Voltage Overshoot Suppression Method of SiC Solid State Power Controller at Turn-off Stage

随着碳化硅(SiC)金属氧化物半导体场效应晶体管(MOSFET)开关速度的提高,针对SiC固态功率控制器(SSPC)在关断初期产生电压尖峰的问题,提出了一种抑制方法。首先以双脉冲测试电路为平台,利用Saber软件,探究寄生电感对SiC MOSFET开关特性的影响。接着在此基础上通过建立SiC SSPC开关模型并进行仿真,重点研究了线路产生的寄生电感对SiC MOSFET关断特性的影响。其次,利用电容储能、放能的方式将线路中寄生电感产生的能量先存储在电容中,再经过功率二极管将存储的能量释放给机内电源的思想,在分析其工作模态的前提下提出了基于能量吸收电路抑制关断电压尖峰的方法。最后,通过仿真分析和搭建硬件电路进行了验证。结果表明,与传统SiC SSPC相比,所提方法可有效抑制由线路寄生电感引起的关断电压尖峰。

With the increase of the switching speed of silicon carbide(SiC)metal oxide semiconductor field effect transistor(MOSFET),a method is proposed to solve the problem of voltage overshoot at turn-off stage of SiC solid state power controller(SSPC).Firstly,relying on the double-pulse test circuit as a platform,the influence of parasitic inductance on the switching characteristics of SiC MOSFET is explored with the help of Saber software.Then,through the establishment of SiC SSPC switch model and simulation,the influence of the parasitic inductance generated by the line on the turn-off characteristics of SiC MOSFET is studied.Secondly,the idea is proposed to store the energy generated by the parasitic inductance in the capacitor first by using the energy storage and discharge method of the capacitor,then the stored energy is released into the internal power supply through the power diode.Based on the analysis of its working mode,a method is presented to suppress voltage overshoot based on energy absorption circuit.Finally,it is verified through simulation analysis and hardware circuit building.The results show that compared with the traditional SiC SSPC,the proposed method can effectively suppress the voltage overshoot at turnoff stage.