基于电压电流的IGBT关断机理与关断时间研究

基于半导体物理和IGBT基本结构, 深入论述了IGBT关断机理, 推导出IGBT关断时间随电压和电流的变化规律: 关断时间随电压的增大而增大, 随电流的增大而减小. 查明了变化规律的物理机理, 仿真和实验结果验证了理论推导与所得变化规律的正确性. 提出采用指数与双曲线复合规律描述IGBT关断时间的变化. 对深化IGBT关断机理和解决电力电子装置死区时间设置等工程问题具有一定的理论意义和应用价值.关键词：关断机理耗尽层载流子关断时间

Investigation into the turn-off mechanism and time of IGBT based on voltage and current

Based on semiconductor physics and the essential structure of IGBT, the turn-off mechanism of IGBT is deeply discussed regarding the problem of turn-off time changing with voltage and current. The laws of turn-off time changing with voltage and current are deduced, i.e., the turn-off time increases with voltage increasing and decreases with current increasing. The physical mechanisms of the laws are found out. The simulation results and experimental results, demonstrate that the derived and the existing law are constant, thereby proving the correctness of the derived law. It is put forward that the law of IGBT turn-off time changing with current and voltage accords with the complex law of exponent and hyperbola. For further studying the IGBT turn-off mechanism and solving the engineering puzzles including the power electronic dead time setting, the present study is significant in theory and practical application.