1. Modeling of Electric Ship Power Systems A. Ouroua, B. Murphy, J. Herbst, and R. Hebner University of Texas at Austin

2. Power system option summary Power Generation Power Conditioning & Distribution Power Conversion Power Consumption Fuel AC or DC Transmission? Motors Loads Transformers Converters Ship Services Ship Services Prime Movers Generators M1 PWM Induction Pulse Loads Rectifier M2 Synchro Synchro./Sep. Exc. Propulsion M3 Cyclo Synchro./PM Diesel Engine Gear M4 G1 Variable Reluctance Synchro./Sep. Exc. Direct Drive M5 G2 Gas Turbine Synchro./PM Optional Energy Storage Propeller Super-conductive G3 M6 Super-conductive Nuclear Power Plant Homo/hetero Polar G4 Homo/hetero Polar Podded Propulsion Non-podded Propulsion Fuel Cells Motor + propeller in single unit Motor on board

4. Permits prediction of

5. Stability

6. Load flow

7. Transient responses

9. System model Pulsed loads Simulink, ACSL, VTB

12. Bearing failure

14. About 0.5 MW

15. Upper Half

17. Ground faults

18. Series faults

19. Step load changes

20. Response of particular interest

21. Surge generation due to stray inductance and filter capacitance

22. Transient circuit representation of faults

23. Transient circuit representation of capacitors

24. Power transients exceeding steady-state source ratings

25. Interest due to surge effects

26. Insulation

28. Pre-breakdown

29. Post-breakdown

30. Develop equivalent circuit from physics-based model

31. Integrate fault circuit model into power circuit model

32. Validate results using test gridTo be done

34. 483 to 10,243 grid points

37. Shape

38. Free path

40. Computation of potential distribution Electric field structure becomes complex during discharge propagation

41. Equivalent circuits Pre-breakdown Post-breakdown

42. Notional temporal behavior Magnitude Time Pre-breakdown Post-breakdown

43. Circuit models can generate “experience base” Insulation Design Steps Supporting Technology Knowledge of insulation medium Material evaluation Statistical analysis High voltage testing Discharge phenomena research Measurement (aging, space charge, dielectric, partial discharge, etc.) Knowledge of an insulation component Evaluation of a way to give a design criterion Design Stress Database of ; Insulation medium evaluation parameters Results of insulation component model and mock up model tests E50 (Area, thickness, volume effect) = x (1 - ns) Deterioration factor Temperature factor Experiences and past records Safety factor Evaluation of influential factors on insulation performance Insulation coordination Electromagnetic field computation Electromagnetic transient analysis Evaluation of voltages applied to apparatus Insulation example

45. Other insulation fails under transient conditions

46. Land-based

47. Switching surges

48. Lightning

49. MVDS for ships

50. Likely switching surges

51. Expect switching surges to be different

54. Ground faults

55. Series faults

56. Step load changes

57. Response of particular interest

58. Surge generation due to stray inductance and filter capacitance

59. Transient circuit representation of faults

60. Transient circuit representation of capacitors

61. Power transients exceeding steady-state source ratings

62. Interest due to surge effects

63. Insulation