Replacement IGBT

Question

Hello I replaced a dead Toshiba IGBT module MG75Q2YS50 that is used in a brake module on a old lathe connected to a vsd i used a Semitrans SKM100GB12v (from E14)which died 1st time i thought specs were close enough when comparing data sheets modern (VSD motor drives ) have this circuit built in ( this is 1999 ) and has separate unit model TG600 the bake unit is used to clamp the rectified mains voltage when the motor is running there is 565vDC at this point (400vAC 3ph input ) when the motor is slowing down the brake unit IGBT turns on a load resister when the voltage gets upto 650vdc the load resister is 13ohm 10kw used with a 37kw motor/vsd so i have measured 42A when it failed the gate trigger is driven by npn/pnp transisters which i removed to check and also checked the snub caps + resister can anyone advise this 1st time user on communities any ideas where to go from here 
 Attachments: MG75Q2YS50.pdf

baldengineer · Answer

Not being an expert on IGBTs, this might be the wrong path. But one thing that stands out for me is the significant difference in switching rise and fall times. It seems the Semikron is faster in both cases. (50ns vs. 38ns for rise, and 100-300 ns vs. 62ns for fall.)

I wonder if the faster edge rates mean you need to modify the snubbing network?

geralds · Answer

Hi acdc90 , ... hm, without a schematic representation, we cannot provide you with any specific help. Have you a schematic diagram that have drawn in voltage values, o-scope plotts, parameter values? Edit: The two IGBTs are not compatible. They have wide different values. https://www.farnell.com/datasheets/2085422.pdf Best Regards Gerald --- 
 Attachments: MG75Q2YS50.pdf

robogary · Answer

At a glance, MG75Q2YS50 Gate Emitter Volts are 20V.

The SKM100GB12VSKM100GB12V , V gate emitter is shown in a couple places one as as 6.5V, one as 15V .

Maybe need to voltage divide the driver voltage down a bit.

Replacement IGBT

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