全碳化硅辅助变流器功率回路振荡问题  

Oscillation of Power Circuit of Full SiC Auxiliary Converter

作　　者：余宝伟 郭希铮[1] 部旭聪 刘伟志 游小杰[1] Yu Baowei;Guo Xizheng;Bu Xucong;Liu Weizhi;You Xiaojie(School of Electrical Engineering Beijing Jiaotong University,Beijing 100044 China;Beijing Zongheng Electro-Mechanical Technology Co.Ltd,Beijing 100081 China)

机构地区：[1]北京交通大学电气工程学院,北京100044 [2]北京纵横机电科技有限公司,北京100081

出　　处：《电工技术学报》2021年第S02期619-626,共8页Transactions of China Electrotechnical Society

基　　金：北京市科技计划资助项目(Z181100004418005)。

摘　　要：以SiC MOSFET替代传统的Si IGBT,可获得更高的开关频率和更低的损耗,但高di/dt造成SiC MOSFET结电容和寄生电感谐振,从而引发高频振荡和过冲电压等问题。该文在充分考虑系统寄生参数的基础上,对于SiC MOSFET关断振荡建立小信号模型,推导解耦电容对于线路寄生电感完全解耦的条件,并在频域上对高频振荡和低频振荡进行分析。在此基础上,该文针对功率回路存在的低频振荡问题,提出一种低频振荡谐振分析模型,建立阻抗分析网络对低频谐振电流进行计算。最后通过仿真和实验结果验证了关断振荡分析以及谐振电流解析的准确性,并对系统参数设计提供了指导意见。Using SiC MOSFET to replace traditional Si IGBT can achieve higher switching frequency and lower losses,but higher di/dt causes resonance between the SiC MOSFET junction capacitance and parasitic inductance,which further produces high frequency oscillation and overshoot voltage.Considering the system parasitic parameters thoroughly,a small signal model for SiC MOSFET turn-off oscillation is established.Then the conditions for fully decoupling the wire parasitic inductance by decoupling capacitor are derived.The high-frequency oscillation and low-frequency oscillation also analyzed in the frequency domain.On the basis of these,a low frequency oscillation resonance analysis model is proposed to accurately analyze low frequency oscillation in the power circuit.Moreover,an impedance analysis network is established to calculate the low-frequency resonance current.Finally,the simulation and experimental results prove the accuracy of the proposed turn-off oscillation analysis model and the analytical calculation method of the resonance current.These methods provide guidance for the design of system parameters.

关 键 词：SiC MOSFET 关断振荡 谐振电流 解析法 解耦电容 

分 类 号：TM46[电气工程—电器]