Avoiding Divergent Oscillation of Cascode GaN Device under High Current Turn-off Condition

被引：0

作者：

Du, Weijing ^{[1
]}

Huang, Xiucheng ^{[1
]}

Lee, Fred C. ^{[1
]}

Li, Qiang ^{[1
]}

Zhang, Wenli ^{[1
]}

机构：

[1] Virginia Polytech Inst & State Univ, Ctr Power Elect Syst, Bradley Dept Elect & Comp Engn, Blacksburg, VA 24061 USA

来源：

APEC 2016 31ST ANNUAL IEEE APPLIED POWER ELECTRONICS CONFERENCE AND EXPOSITION | 2016年

关键词：

Gallium nitride device; cascode; capacitance mismatch; avalanche; divergent oscillation; HEMT; POWER;

D O I：

暂无

中图分类号：

TE [石油、天然气工业]; TK [能源与动力工程];

学科分类号：

0807 ; 0820 ;

摘要：

Cascode structure is widely used for high voltage normally-on GaN devices. However, the capacitance mismatch between the high voltage GaN device and the low voltage normally-off Si MOSFET may induce several undesired features, such as Si MOSFET reaches avalanche during turn-off, and high voltage GaN device loses ZVS turn-on condition internally during soft-switching turn-on process in every switching cycle. This paper presents another issue associated with the capacitance mismatch in the cascode GaN devices. Divergent oscillation could occur at high current turn-off condition, and eventually destroy the device. The intrinsic reason of this phenomenon is analyzed in detail in this paper. A simple solution is proposed by adding an additional capacitor whose position is critical and should be optimized. Experimental results validate the theoretical analysis, and show that the proposed method improves device performance significantly under high current turn-off condition.

引用

页码：1002 / 1009

页数：8