1、Over-temperature, Overcurrent Adjust the Vge/Rg to decrease the di/dt; Select the low impedance capacitors; Place the capacitor as close as IGBT module to reduce the loop inductance; Connect the power and snubber loop with IGBT module as short as possible; Page 16 Copyright Infineon Technologies 200
2、7. All rights reserved. 22.05.2007 For internal use only General RCD snubber RCD snubber, other RC and RCD snubbers: Can realize even smaller Vcepeak than RCD snubber. Snubber R would have very big power dissipation . Low impedance R is hard to find. Will not influence IGBT turn on Huge losses on sn
3、ubber R Quite hard to find a suitable R value, when switching frequency is high Be used below hundreds Watt application Seldom used Page 17 Copyright Infineon Technologies 2007. All rights reserved. 22.05.2007 For internal use only C Snubber circuit L2 OV reduction C position is close to power termi
4、nals as possible. Page 18 Copyright Infineon Technologies 2007. All rights reserved. 22.05.2007 For internal use only Loop (DC capacitor, C snubber) L1: DC capacitor inductance + bus bar inductance L2: module terminal to snubber capacitor inductance L31/L32: Upper/Bottom IGBT internal stray inductan
5、ce L4: snubber capacitor internal stray inductance Loop A: bus LC oscillation loop Loop B: commutation loop through snubber Page 19 Copyright Infineon Technologies 2007. All rights reserved. 22.05.2007 For internal use only Over-voltage protection V3 T/2 V2 Vcc V1 tiddLV 1 tiddLV 22 CiLV c 213 Page
6、20 Copyright Infineon Technologies 2007. All rights reserved. 22.05.2007 For internal use only Cs vs Bus bar construction L L2 L2 Cs Ic L1 L1 DC + DC - Ic1arm Ic3arm Ic2arm Page 21 Copyright Infineon Technologies 2007. All rights reserved. 22.05.2007 For internal use only Overshoot voltage & Snubber
7、 capacitor Vdc=1.8kV, Ic=528A, Vcp=2.61kV Vdc=1.8kV, Ic=529A, Vcp=2.43kV Cs=1.8uF Cycle: 5us Cs=0uF Cs=3.6uF Cycle: 7us Vdc=1.8kV, Ic=530A, Vcp=2.43kV Reduce the overshoot voltage to appropriately chose the snubber capacitor value, or else the oversize value is useless. Page 22 Copyright Infineon Technologies 2007. All rights reserved. 22.05.2007 For internal use only
