I had a problem with an inverter and i did not understand the problem:
I have a inverter full bridge, input 125 Vcc and output 230 Vac 60 Hz 4 kVA, with insulation transformer.
The operation frequency is 15 kHz and i used two IGBT FF200R12KT4 per channel.
The gate driver is all discrete with a fast opto-coupler (i want to use a dedicated Infineon gate driver in the future), is a traditional circuit in my company and i need to use it. The power supply of the high side is a bootstrap circuit.
But some inverters return for maintenance with the gate and collector of igbt in short circuit or with low resistance (about 10/20 ohms), in mostly cases the problem happens in the high side of IGBT.
In the tests in production, everthing is ok, but the inverter is damaged in a short time of use by the consumer.
What is the causes of this kind of problem in the gate/collector?
I understood that during the maintenance of inverters you have found some failed modules. It would be very good to send them to us for the analysis. After investigation you will get a report. Please contact your distributor or sales representative to check on how to do this.
Have you solved your issues? It looks I have something very similar here, I am from https://worldcams.tv/united-kingdom/london/city-views. It is interesting whether users here can help you find the reason for this. Or should I better contact the distributor and not touch anything myself? What is your opinion? Waiting for your suggestions and may thanks for reading