How to connect IGBT module FS20R06XL4
Hi all,
I have a few questions about igbt module, if someone could reply, it would be great
Data about components to check my values:
FS20R06XL4 ( igbt module from eupec )
DC Collector current T°c= 25 ° Ic=26A
T°c= 70°c Ic=20A
Vge Threshold 5,5 V typical
4,5 V mini
Repetitive peak collector current Icrm tp=1ms 40A for T°c = 70°c
FOD3120 ( optocoupler from Fairchild )
" Absolute Maximum Ratings " Io Peak Peak Ouptut current 3A
MEA1D1509SC ( dc/dc converter )
Output 18V and +- 56 mA
First question:
Gate Resistor Value ( From AN 7003 p6/10 Gate resistor-Principles and application )
Rg mini = ( Vg on -Vg off ) / IGm
Vg on = 18V
Vg off = Threshold voltage for FS20R06XL4 is about 4,5V mini, so my choice is 4V . Right or wrong ?
Io Peak Maximum Current for FOD3120 is 3A
Rg mini = ( 18 - 4 ) / 3 ≈ 5 Ω Right or wrong ?
Second question:
Now i need to power an inductive load ( brushless ) with 5A average current.
First: check if V positive rail is about 0,8 Vce in maximum ratings.
Then rough estimate: surge current is about 6 x average current, so I must see Repetitive peak collector current in the data.- IRCM -
Value is about 40A, so it's ok. Right or wrong?
I only want to know if surge current time is generally , in 1 mS or more?
Any idea?
Third question ( Extracted from Fuji IGBT module application manual p 22 /95 )
" On an installed IGBT , if the gate circuit is faulty or inoperative ( while the gate is open ), the IGBT may be destroyed when a voltage is applied to the main circuit.
In order to prevent this destruction, it's recommended to add, between gate and emitter:
- resistor Rge
- diode - avoiding overvoltage, i think ? - and how to choose this component ? TVS bidirectionnal diode or other?
- capacitor value of 10 % of Cge
One more thing i don't understand, these added components are mandatory in all design cases or only for " pcb + wire feed " ------> IGBT bricks?
Is it the only way to do the job ?
Thanks a lot.
jm