Hybrid Voltage Balancing Approach for Series-Connected SiC MOSFETs for DC–AC Medium-Voltage Power Conversion Applications

Xiang Lin,Lakshmi Ravi,Rolando Burgos,Dong Dong

IEEE Transactions on Power Electronics（2022）

引用 11|浏览11

暂无评分

摘要

Using series-connected SiC mosfet s to enable high-speed switching units is desired to meet the growing demand for high-density medium-voltage power converters. Due to its fast-switching speed, the voltage sharing of series-connected SiC mosfet s is more sensitive to the surrounding parasitic components and gate-signal mismatch, which results in more challenges for the voltage balancing control. In this article, the gate turn- off delay-time control is first used as an example to analyze the limitations of the existing active voltage balancing (AVB) control methods: 1) AVB control has a limitation of adjusting the delay time accurately under ac current conditions; and 2) the voltage imbalance of the body diodes cannot be solved by AVB control. To achieve voltage balancing control of series-connected SiC mosfet s for ac current, this article proposes a new hybrid approach: 1) passive dv/dt compensation: one small compensation capacitor is applied to balance the measured nonuniform distribution of parasitic capacitors ; and 2) active gate signal turn- off time adjustment: a digital closed-loop delay time control is applied to compensate the gate signal mismatch of mosfet s. To verify the proposed balancing approach, a single-phase pump-back test is conducted to show the improvement of voltage sharing of both mosfet s and body diodes.

查看译文

关键词

Parasitic capacitors,series-connected SiC MOSFETs,voltage balancing

AI 理解论文

溯源树

样例

生成溯源树，研究论文发展脉络

Chat Paper

正在生成论文摘要