| Firstly, this thesis analyzed the aging mechanism of IGBT and the influence of aging on main electrical parameters in detail. Considering that the bonding lines loss and solder layer fatigue would lead to the increase of on-state resistance and thermal resistance separately. The increase of thermal resistance will lead to the changes of main temperature-sensitive parameters directly. Secondly, the thesis presents a improved temperature-sensitive parameters(TSP) method based on on-state voltage drop. The method is used for measuring jection temperature in the condition of large current, which provides a basis to analyze the thermal resistance before and after aging. The changes of on-state resistance and temperature-sensitive parameters are the direct performance of IGBT’s aging. Built a model for the IGBT, then analyzed the process of aging of IGBT by simulation. Which proved the conclusion that the switch speed and threshold voltage decrease with the process of aging, while the on-state voltage decreases in the condition of small current and increases in the condition of large current with the aging of IGBT.Built an accelerating aging test platform for IGBT, then did two kinds of accelerating tests, which were constant temperature aging test and floating temperature aging test. The aged IGBTs were used as faults to inject into the experiment circuit. At last, the thesis analyzed the influence on the output voltage of DC/DC circuit including a full-bridge inverter by experiment and simulation, and got the conclusion that the aging of IGBT would lead to the shift of frequency spectrum and the changes of the amplitudes of some frequency points. |
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