The aging and malfunction of devices with great power have been the main causes of the collapse and failure of grid systems. Since they are frequently used in grid systems, the failure of a solid-state-transformer has a great impact on the energy-saving and normal operation of network systems. Moreover, the main switching element of a solid-state-transformer is a welding type IGBT, which is also the most fragile part. First, the uneven current flow phenomenon of paralleled IGBT modules is introduced. Then, the main factors influencing solid-state-transformer failure, along with the short-circuit and open-circuit faults of IGBTs are analyzed. After the derivation \(V_\text{CE}\), it can be seen that it is related to the short-circuit and open-circuit faults of IGBTs. After comparison and analysis, one type of solid-state-transformer should be chosen to be widely applied and with integral functions for models and simulations. The IGBTs in solid-state-transformers vary in terms of fault condition and position, which influences the internal and external electrical parameters of systems. Therefore, it is proposed that collector-emitter voltage can be used to characterize the fault conditions of solid-state-transformers. Through simulation verification and waveform observations, it can be seen that the collector-emitter voltage and V_M, which is the voltage of the primary side of the transformer in a solid-state-transformer, can be used to characterize the failure condition of the internal converter of the solid-state-transformer.

大功率设备的老化和故障已成为电网系统崩溃和故障的主要原因。由于它们经常在电网系统中使用，因此固态变压器的故障会对网络系统的节能和正常运行产生重大影响。而且，固态变压器的主要开关元件是焊接型IGBT，这也是最易碎的部分。首先，介绍了并联IGBT模块的不均匀电流流动现象。然后，分析了影响固态变压器故障的主要因素，以及IGBT的短路和开路故障。推导\（V_ \ text {CE} \）之后可以看出，这与IGBT的短路和开路故障有关。经过比较分析，应选择一种类型广泛的固态变压器，并具有用于模型和仿真的积分功能。固态变压器中的IGBT在故障条件和位置方面会发生变化，这会影响系统的内部和外部电气参数。因此，建议使用集电极-发射极电压来表征固态变压器的故障状况。通过仿真验证和波形观察，可以看出集电极-发射极电压和V _M固态变压器中变压器初级侧的电压可以用来表征固态变压器内部转换器的故障状况。