摘要
受内部寄生参数与结电容的影响,碳化硅(SiC)功率器件在高速开关过程中存在极大的电流电压过冲与高频开关振荡,严重影响了SiC基变换器的运行可靠性。因此,该文首先对SiC MOSFET开关特性进行深入分析,揭示栅极电流与电流电压过冲的数学关系;然后提出一种变栅极电流的新型有源驱动电路;通过对SiC MOSFET开关瞬态的漏极电流变化率dI_(d)/dt、漏-源极电压变换率dV_(ds)/dt以及栅极电压V_(gs)的直接检测与反馈,在开关过程的电流和电压上升阶段对栅极电流进行主动调节,抑制电流电压过冲与振荡;最后在多个工况下对本文所提方案进行实验验证。结果表明,与常规驱动方案相比,该文方法减小了30%~50%的电流电压过冲,有效抑制振荡与电磁干扰,提高了SiC MOSFET变换器的运行可靠性。
Due to the influence of internal parasitic parameters and junction capacitance,silicon carbide(SiC)power devices have great voltage and current overshoot and high-frequency switching oscillation in the process of high-speed switching,which seriously affects the operation reliability of SiC-based converters.In this paper,firstly,switching characteristics of SiC MOSFET are deeply analyzed to reveal the mathematical relationship between gate driving current and voltage and current overshoot.Then,a new active gate drive circuit with variable driving current is proposed.The gate current is actively regulated in the current or voltage rising stage of the switching process to suppress voltage and current overshoot and oscillation through the direct detection and feedback of the transient drain current change rate dI_(d)/dt,drain-source voltage change rate dV_(ds)/dt and driving voltage of SiC MOSFET V_(gs).Finally,experimental results show that the proposed method can effectively reduce voltage and current overshoot by 30%~50%,suppress the oscillation and electromagnetic interference,and improve the operation reliability of SiC MOSFET converter.
作者
刘平
陈梓健
苗轶如
杨江涛
李伟
Liu Ping;Chen Zijian;Miao Yiru;Yang Jiangtao;Li Wei(College of Electrical and Information Engineering Hunan University,Changsha 410006,China)
出处
《电工技术学报》
EI
CSCD
北大核心
2022年第17期4446-4457,共12页
Transactions of China Electrotechnical Society
基金
江苏省输配电装备技术重点实验室开放资金(2021JSSPD11)
湖南省自然科学基金(2021JJ30116)资助项目。
