绝缘栅型双极晶体管(IGBT)采用串联和并联方法构成大功率开关组件能够有效提高工作电压和电流,是实现开关重频高功率应用的主要技术途径,同时也存在着动、静态的匀压、匀流问题。从电路层面详细分析了IGBT串并联运行时导致电压、电流不均衡的主要原因及其表现,研究了动静态不均衡的发展过程及其影响因素,针对性地提出了电阻/电容/二极管(RCD)缓冲网络及电流平衡变压器等匀压、匀流措施,解析推导出了IGBT串、并联模块的设计判据,建立了相应的等效电路模型,对所提出的解决方案进行了仿真验证。仿真模拟结果表明,所提出的方法是可行可靠的。

Insulated gate biploar transistors(IGBTs) operating in series and parallel,which endure high voltage and heavy load currents,bring the problems of static and dynamic voltage and current balancing,which can be minimized by using passive balancing methods. This paper analyzes the main factors causing unbalance in theory and describes the passive snubber circuit used to equalize the voltage sharing and current balancing for serial and parallel IGBTs in both switching transients and steady state. The passive snubber circuit for voltage sharing consists of an RCD snubber and a balancing resistor. The current balancing technique consists of derating the parallel devices and impedance balancing by using a current balancing transformer. The snubber circuit was optimized by modeling the behaviors of IGBTs. The proposed technique was simulated for two IGBTs and the results show good balancing.