EMC Modeling of IGBT Motor Controller

1. EMC Modeling of IGBT Motor Controller Missouri University of Science and Technology & Rose-Hulman Institute of Technology Departments of Electrical and Computer Engineering RHIT Daniel Baker Andrew Gawlik Gareth Shields Chris Valenta Dr. Ed Wheeler UMR Matt Halligan Igor Izyumin Clint Patton Jason Phillips Dr. Jim Drewniak

2. Last Week: Phase 1 ‘3L Model’ Last Week’s Model Note that C3 is shorted to ground.

3. IGBT Phase 1: Simulated Impedance vs. ‘3L Model’ Last Week’s Model

4. IGBT Phase 1: Measured Impedance vs. ‘3L Model’ Last Week’s Model

5. Analysis: Poles and Zeros of the ‘3L Model’ • Goal: To learn which circuit elements determine which poles and zeros. Last Week’s Model

6. Mathcad: ‘3L Model’ Transfer Function, Zeros, and Poles

7. Mathcad: Plotted ‘3L Model’ Transfer Function POLES ZEROS

8. Analysis Results Conclusions: The transfer function accurately represents the ‘3L’ model. The poles and zeros do not have a simple relationship based on the circuit elements.

9. Observed ‘Glitch’ First Phase Leg Re-Measured • Attempt to reproduce the ‘glitch’ at high frequencies. • Impedance zeros do not line up because of the changing probe inductance (L1).

10. New Ltot = 14.9 nH Old Ltot = 13.7 nH Comparison of Old vs. New Measurement

11. Re-Measured Impedance vs. Simulated Impedance

12. Lprobe CafA,LafA Lb2 CafG LafG Lb1 CafA,LafA New Geometry-based Phase 1 Model ‘M2’ Model

13. New Geometry-based Phase 1 Model • Uses simulated branch inductance values • Uses measured capacitance values ‘M2’ Model

14. Measured (Former) Impedance vs. ‘M2’ Model

15. Simulated Impedance vs. ‘M2’ Model

16. Sum of Bridge Inductances Note: Both the 3L and the M2 model are based on measured capacitances and different simulated subsections of Phase Leg 1.

17. Possible Sources of Error • Need to use Simulated Capacitances • Transient vs. Frequency Solver? • CafG = 62 pF using frequency solver • CafG = 59 pF using transient solver • Accuracy Level • Lprobe = 3.7 nH @ 1e-9 • Lprobe = 4.36 nH @ 1e-12 • Simulation probe concentrates the current – adds unnecessary inductance to each branch inductance simulation? • Added inductance due to the narrow short to ground?

18. ‘M2’ Model Bridge Inductances: Simulation Results

19. First Phase Leg: Lprobe Simulation Setup

20. First Phase Leg: Lprobe Simulated Impedance Lprobe = 4.36 nH

21. First Phase Leg: LafA Simulation Setup

22. First Phase Leg: LafA Simulated Impedance LafA = 2.33nH

23. First Phase Leg: Lb1 Simulation Setup

24. First Phase Leg: Lb1 Simulated Impedance Lb1 = 3.76 nH

25. First Phase Leg: LafG Simulated Impedance

26. First Phase Leg: LafG Simulated Impedance LafG = 1.47nH

27. First Phase Leg: Lb2 Simulation Setup

28. First Phase Leg: Lb2 Simulated Impedance Lb2 = 2.40 nH

29. First Phase Leg: LafI Simulation Setup

30. First Phase Leg: LafI Simulated Impedance LafI = 3.83 nH

31. Old Slides

32. Comparison of Measurement/Simulation Values

33. First Phase Simulation w/ Probe Inductance

34. Phase 1 w/ Probe Inductance Simulation Calculated L: 15.0 nH -Probe adds 2.6 nH

35. First Phase Leg Preliminary Model • A preliminary model for the first phase leg was created. • Capacitances: Measured Area Fills A, G, and I. • Inductances: Selected to provide a rough match with the first pole and zero.

36. UMR: First Phase Measured vs. Preliminary Model

37. Phase 1 Model: Using Three Inductances • An unwanted resonance was found in the four inductance model. • L3 was replaced by the sum of L3 and L4. • L4 was set to zero.

38. IGBT Phase 1: Simulated Impedance vs. 3L Model

39. IGBT Phase 1: Measured Impedance vs. 3L Model