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Regenerative power in induction motor ( braking resistor)

I am facing big issue in the Induction motor drive system. I am using IM drive system with three phase inverter and three phase 2hp induction motor with Dspace 1104 .I am running the motor at rated speed 1400 rpm with 540vdc coming from rectifier . I am using 4 capacitor as filter circuit. My problem when i reverse the motor speed ,my IGBT always shorten ( The IGBT rate is 1.2kv and 75A),while in motoring mode the drive system can run perfectly at 540vdc and ONLY trip if i reverse the speed from +1400 to -1400 rpm .
I suspect the regenerative power coming from the motor,so i installed 8 resistor with 2.1K 5 watt to absorb the regenerative power,however this effects the drive system in the motoring mode( forward speed) it broke the igbt at 400 vdc .So i dont know what resistor value i should select and what wattage in order to prevent the regenrative power and doest affects the drive in the motoring mode.
 
Haven't seen any details about your project so I can't know, but the first that stroke me is that you probably have negative timing when running backwards.
 
The normal method in a VFD is to switch off the control devices and turn on the braking resistor, IOW the resistor is not in circuit during motoring.
M.
 
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