Digital Twin Approach for IGBT Parameters Identification of a Three-Phase DC-AC Inverter

In three-phase dc/ac inverter, the power device is one of the most prone links to failure. Once it fails, it will cause serious accidents. Therefore, it is of great significance to carry out more accurate condition monitoring. In this paper, a digital twin method for IGBT parameter identification of a three-phase dc/ac inverter is proposed. The state monitoring of IGBT is emphatically studied, and the digital twin model of the three-phase inverter circuit is established. A particle swarm optimization algorithm is used to iterate the characteristic data, so that the digital twin model is gradually approximated with the physical circuit parameters. It is worth noting that by calculating the output part and core part of the digital twin model in order, the number of characteristic quantities identified at the same time is reduced, and the collected output current and voltage waveforms are screened, and different frequency quantities are selected to build a suitable target function. Through this method, the saturation voltage of IGBT, the forward voltage of the reverse parallel diode and the inductance value are accurately identified. Finally, a three-phase dc/ac inverter is built. Simulation and experimental results verify the effectiveness of this method.