Samsung AM072BXV Series - Case Study - Poor Cooling Caused by IPM Overheated

Samsung Electronics 170
Troubleshooting
4-4-13 Case study – Poor cooling caused by IPM overheated
- Problem : Poor cooling
- Condition : Compressor frequency doesn’t increase, IPM temperature is too high, Low pressure is high
- History
: 13.05.07 Trial operation
: 13.05.27 Inverter PBA, EMI PBA, Reactor replacement
→→
- Root cause : Bad contact of IPM cause by faulty bolt.
Test 5/27
5/28
case 1 case 2 case 3
upper PBA change lower PBA change exchange PBA position each other
Upper PBA
(inv 2)
PBA_A
freq. 55hz
IPM 89

PBA C
freq. 54hz

PBA C
freq. 55hz
IPM 79

PBA D
freq. 55hz
IPM 81 
Lower PBA
(inv 1)
PBA B
freq. 52hz
IPM 86

PBA B
freq.51hz
IPM 92 
CB D
freq. 52hz
IPM 91 
PBA C
freq. 52hz
IPM 89 
Bad
Bad
IPM1
IPM
Heat sink
IPM2
There is no thermal grease.
IPM 2- Reattach
4-4 Case study for trouble shoots (cont.)
- Conclusion : Change bolt to new one, reattach the IPM → Problem solved
Date 6/5 6/5
OD Temp 41.6 40.8
High pressure 34.7 36.4
Low pressure 10.5 9.9
Comp1 61 82
Comp2 64 85
Current1 14.9 20.2
Current2 14.2 19.3
IPM1 88 85
IPM2 90 86
Reattach #2 Solved
Date 5/28 5/29
OD Temp 38 38
High pressure 30.5 30.4
Low pressure 10.9 11.4
Comp1 52 52
Comp2 55 55
Current1 12.3 15.3
Current2 10.3 14.2
IPM1 86 89
IPM2 89 81
Basic Reattach #1




- Hz Hold : 36 kgf/㎠
- Hz Down : 37 kgf/㎠