适用于IGBT串联的有源钳位动态电压均衡电路研究

Active Clamping Dynamic Voltage Balancing Circuit for the IGBTs Series Connection

为解决由栅极驱动信号不同步引起的多个IGBT串联电压不均衡问题,以实现串联IGBT在大功率高电压场合中的应用,笔者采用基于栅极端电压均衡技术的有源钳位动态电压均衡电路实现动态电压均衡,该电路具有响应速度快、损耗小、可靠性高等优点。通过建立IGBT串联仿真和实验电路,对该均压辅助电路进行仿真分析和实验验证。结果表明,该均压辅助电路在IGBT串联运行时不仅能够很好地抑制IGBT栅极驱动信号不同步造成的电压不均衡,而且能够有效防止过电压的发生,确保了IGBT串联的安全运行。

Series connection of IGBT devices can meet the requirements of high-voltage and high-power conversion, but the imbalance of voltage caused by the asynchrony gate drive signals is a key problem of the IGBTs series connection. For realizing the voltage balancing preferably, an active clamping dynamic voltage balancing circuit based on the gate terminal voltage balancing technology for the IGBTs series connection is presented in this paper. It shows fast response, low loss and high reliability, and so on. Then, the effect of active voltage balancing auxiliary circuits for series connected IGBTs is analyzed by the simulation and experiment. Finally, the results show they can not only suppress the imbalance of voltage caused by the asynchrony gate drive signals, dramatically. It is guaranteed that a circuit including series but also diminish overvohage across IGBTs connected IGBTs can operate safely