First, these are the componentes I'm using on my PCB, click on them to see the datasheets:
Gate Driver
Power MOSFET
Freewheeling diode
Current Sensor
The schematic is attached below. Sorry if I'm not using some right symbologies. I took the schematic from the PCB software.
Vbus voltage comes from rectified and filtered mains (110VAC).
PWM frequency is 10 kHz
The gate driver is isolated, so GND1 is ground from rectifier, an GND2 is the digital ground.
I tested the PCB with two different motors.
Motor 1:
130VDC
25.5A
Motor 2:
130VDC
27A
These are the steps that I followed before the transistor blew:
1- I tested the circuit with a light bulb first. Everything ok.
2- Then, I connected motor 1 with no load. Everything ok.
3- I connected motor 2 with a slight load. It started ok at 5% of duty cycle. Then, I increased duty cycle to 10% and the transistor blew up, so the motor went to max speed uncontrollably.
I haven't programmed the fast overcurrent detection from the current sensor. That way I would have probably saved the mosfet.
The question is... what could be the cause of this? high dv/dt and di/dt? need an snubber? I have a lot of mysteries in mind right now.

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