Characterization of IGBTs Short-Circuit Fault in an Arm Configuration Considering Devices Intrinsic Discrepancies

The short circuit fault (SCF) is a dangerous condition threatening the health of insulated gate bipolar transistors (IGBTs). Thus, SCF can be considered a critical issue for the reliability of power electronic converters. The SCF behavior of IGBTs and their failure factors when operating in an arm configuration are the focus of this paper. This paper considers the non-idealities of the circuit and differences in IGBT parameters and describes the SCF fault. It was found that there is a significant voltage imbalance among the IGBTs during SCF, which leads to a notable energy imbalance between the devices. The voltage and energy imbalances depend significantly on the inevitable discrepancies in the circuitry and internal parameters of the IGBTs. To verify these findings, a detailed PSPICE simulation is conducted, and experimental results are also reported for different scenarios in SCFs. The results confirm that short-circuit energy among the devices can differ significantly. Moreover, the voltage distribution across IGBTs strongly depends on both their intrinsic parameter mismatches and the operating conditions.