中高压大功率IGBT驱动器有源箝位技术研究

Research of Active Clamping Circuit for Medium-high Voltage High Power IGBT Driver

中高压大功率终止型绝缘栅双极性晶体管(IGBT)中驱动器一般通过有源箝位电路来抑制其大电流关断时的电压尖峰。提出将有源箝位电路等效为典型闭环反馈控制系统并进行线性化处理的时域分析方法,用于分析有源箝位过程初期的动态性能。提出一种针对稳定箝位过程的静态分析方法,为有源箝位电路参数取值及确定箝位工作点提供依据。针对双N-MOSFET驱动级,设计了一种对驱动级进行棒-棒调节的有源箝位电路,该电路能降低瞬态电压抑制二极管(TVS)击穿电流,从而降低其在箝位过程中的损耗。最后通过仿真和实验结果验证了理论分析和电路设计的可行性、准确性、有效性。

Medium-high power filed stop insulated gate bipolar transistors （IGBT） suppress its voltage spike when turned off under high collector current by active clamping circuit generally.Proposes a time domain linear analysis method in which the active clamping circuit is equivalent to typical closed loop feed-back control system for the ini- tial dynamic characteristics analysis of the clamping process.A steady state static analysis method is proposed for con- figuring the parameters and operating point of the active clamping circuit.A new active clamping circuit which is compatible with the dual N-MOSFET drive stage is designed.It regulates the drive stage by bang-bang control method, resulting in a fast dynamic response ability and lower transient voltage suppressor（TVS） breakdown current, and then limiting the power loss during clamping process.At last the simulation and experiments were carried out to verify the feasibility, accuracy, and effectiveness of the theory and design proposed.