1. Condition Monitoring for Power Electronics Reliability (COMPERE)1
Condition Monitoring for Power Electronics Reliability (COMPERE)
Shaoyong Yang
Angus Bryant
Phil Mawby
Nov 3rd 2008

2. Contents Work plan – where we are and tasks. Back-to-back test rig.1
Contents
Work plan – where we are and tasks.
Back-to-back test rig.
3. Review paper
Discussion and Conclusion
4. Conference next year
EPE, ECCE, ISIE 2

3. 1
1. Original Work plan
Power Converter Modelling
Modified work plan 3

4. 1
Modified work plan 4

5. LUT packaging damage Or spectral information Vge shift… 5 ΔT Tm1
LUT packaging damage ΔT Tm
Or spectral information
Vge shift…
ΔVCEsat
ΔRth
ΔVCEsat
ΔRth Δt
ΔRth
ΔVCEsat 5

6. 1
Modified work plan 6

7. Power Device Model –50°C ~ +150°C, Voltage & current.
Compact models for IGBTs and diodes:
Ambipolar diffusion equation describes carrier distribution.
Proven over wide range conditions:
–50°C ~ +150°C, Voltage & current.
Have to be tailored/parameterised:
On-state
Switching behaviour (the right figure); 7

8. Tests for parameterisation1
Tests for parameterisation
SKM75GB123D
1200 V, 75 A 8

9. Matching for inductive switching1
Matching for inductive switching
Inductive switching shown here.
IGBT turn-on (left), IGBT turn-off (right).
Instantaneous power dissipations shown to validate switching energies. 9

10. Matching for on-state characteristics1
Matching for on-state characteristics 10

11. 1
Look-up table
IGBT power losses (W) for whole switching cycle plotted as a function of load current (A), duty ratio and temperature (°C). 11

12. Power Converter Modelling1
Power Converter Modelling
IGBT model used in full converter modelling
Simulation of every switching event is too time-consuming.
Look-up table of losses is used instead:
Generated from device models in MATLAB/Simulink.
Gives losses as a function of load current and temperature.
Simple converter/heatsink model then simulates device temperature.
Rapid and accurate estimation of device temperature for whole load cycle.
Converter simulation
Look-up table
Simulation controller
EXTERNAL
CONDITIONS
LOSS DATA
Device temp.
Power diss.
Heatsink model
Compact models
System modelling
Device modelling 12

13. Progress for parameterisation1
Progress for parameterisation
1 Switching and on-state tests have been carried out.
2 Full parameterisation of the selected Semikron module is expected in 2-4 weeks. 13

14. 1
2.B2B test rig
Designed to work
at Vdc=450 V 14

15. 1
B2B test rig 15

16. 1
B2B test rig 16

17. Gate circuit Space vector width modulation+ PID control.1
Gate circuit
Space vector width modulation+ PID control.
DC 100 V, 10 A tested.
Gate outputs
Gate
drivers
Signal+power
inputs
buffer 17

18. 3. Review paper 1 Title – Peter’s suggestion
Condition monitoring for reliability in power electronics converters – a review?
2 Discussion and conclusions
Many thought it is not specific and deep enough. 18

19. Discussion part (1) 3D FEM
Pros: investigate stress effect on bond-wire and solder layer.
Cons: does not directly give predict reliability.
Not feasible for drive cycle modelling.
Thermal electrical (TE)
Pros: feasible for drive cycle modelling, and gives temperature information.
Thermal-mechanical (TM)
Pros: gives reliability and predict lifetime- necessary for CM.
Cons: complicated + interdisplinary.
3D FEM knowledge may be useful to learn thermal stress effect.
TM should be built based on TE since the latter provide temp info. 19

20. Discussion part (2) Any suggestion for Table II?1
Discussion part (2)
Any suggestion for Table II?
How to link power device part and CM techniques? 20

21. Conclusion CM will be emphasized, so the point (1) may be deleted.
Main structure may be:
Fault diagnosis useful…
Modelling is an essential part…
CM techniques…
“Conclusion will need a re-write once the discussion has been sorted out”– Angus. I agree. 21

22. 4. Conferences EPE 09: abstract deadline, 3 Nov1
4. Conferences
EPE 09: abstract deadline, 3 Nov
ECCE 09: abstract deadline, Jan 15, 09
ISIE 09: Feb, 09
I will check again this part. 22

23. Thank you for your attention!1
Thank you for your attention! 23