Patent ID: 11874341
Assignee: HEFEI UNIVERSITY OF TECHNOLOGY
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 4:
5. The method for monitoring the online state of the bonding wire of the IGBT module according to claim 2, wherein a specific method for establishing the three-dimensional data model of the IGBT with the broken bonding wire in the step 3 comprises:
under a premise of protecting a encapsulation of the IGBT power module, performing a breaking experiment on the bonding wire of the IGBT power module manually to simulate a falling failure of the bonding wire due to a severe working environment or normal ageing in an actual working condition; each time after one bonding wire is broken, placing the IGBT power module in the high-low temperature experimental box, simulating the environment temperature by adjusting the working temperature of the high-low temperature experimental box, wherein the environment temperature variation range simulated in the high-low temperature experimental box is 30-130° C., and controlling the forward on current variation range of the IGBT power module to be 20-60 A by changing the load of the full bridge inverter circuit; measuring the saturation voltage drop of the IGBT power module in the full bridge inverter circuit once at an interval of 2 A of the forward on current of the IGBT power module when the environment temperature simulated in the high-low temperature experimental box is at an interval of 5° C. until all bonding wires in the IGBT power module are broken completely; and performing surface fitting on experimental data by using a cftool tool box in Matlab to obtain a saturation voltage drop curved surface of a failed IGBT power module with the broken bonding wire, wherein the quantity of the saturation voltage drop curved surfaces of the failed IGBT power module with the broken bonding wires is equal to the quantity of all bonding wires of the IGBT power module, and each time one more bonding wire is broken, a corresponding saturation voltage drop curved surface of the failed IGBT power module with the broken bonding wire is obtained.