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
: 13.05.27 IPM temperature ↑
→
comp Hz ↓
→
cooling capacity ↓
- 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
IPM 82℃
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
※ IPM Temp Protection
- Hz Hold : 90℃
- Hz Down : 93℃
※ HP Protection
- Hz Hold : 36 kgf/
㎠
- Hz Down : 37 kgf/
㎠
