BRADLEY UNIVERSITY Department of Electrical and Computer Engineering Sr. Capstone Project Advisor: Dr. Anakwa Student: P

1. BRADLEY UNIVERSITY Department of Electrical and Computer Engineering Sr. Capstone Project Advisor: Dr. Anakwa Student: Paul Friend

2. Overview: • Background Information • Halbach Array • Inductrack • Sensors • Propulsion Methods • Controls • Physical Design • Theories • Parts and Equipment • Schedule • Resources

3. Background Information • Inductrack: • Created by Richard F. Post in the late 1990’s at Lawrence Livermore National Laboratory • 20 meter test track • Burst Propulsion

4. Background Information • Inductrack: • Contracted by NASA for Satellite Launcher • Low-Speed Urban Maglev Program

5. Halbach Array • Created by Klaus Halbach • Creates a strong, nearly one-sided magnet with a sinusoidal field by directing the magnetic fields.

6. Halbach Array • Standard Formation • Expanded Wavlength • Doubled Method

7. Halbach Array B0 = Br (1 – e-2πd/λ)[(sin(π/M))/( π/M)] [Tesla] B0 = 0.82843 (1/2” Gr. 38 NdFeB Cube Magnets) Bx = B0 sin((2π/λ)x) e-(2π/λ) (y1 – y) [Tesla] By = B0 cos((2π/λ)x) e-(2π/λ) (y1 – y) [Tesla]

8. Inductrack • Basic Methods: • Array of Inductors • Laminated Copper • Laminated Aluminum

9. Inductrack • Array of Inductors • Used in 1st Inductrack • Insulated Litz-wire • Ferrite Loading

10. Inductrack • Laminated Copper • Square Litz-wire bulks • Used for Low-Speed Urban Maglev Program

11. Inductrack • Laminated Copper & Aluminum • Thin Sheets • Slots cut to guide eddy currents • Slots terminated at ends for “shorts”

12. Inductrack • Physics • Lenz’s Law • Discovered in 1834 • Eddy currents created due to moving magnetic field • (Not guided)

13. Inductrack Physics Circuit Equation: V = L dI/dT + RI = ωφ0 cos(ωt) [V] Lift/Drag Ratio: Lift/Drag = <Fy>/<Fx> = ωL/R = (2πv/λ) (L/R) Power Efficiency: K = <Fy>/<Fx> = (2π/λ) (L/R) [Newtons/Watt]

14. Inductrack Physics λ optimum = 4π y1 [m] Magnet thickness of λ/5 Only valid for max. load for min magnet weight and for original Inductrack 50:1 levitated weight/magnet weight ratio

15. Inductrack Inductrack II

16. Sensors • Types: • Velocity Sensor • Optical Sensor • Magnetic Sensor

17. Propulsion • Types: • Linear Synchronous Motor (LSM) • Linear Induction Motor (LIM)

18. Propulsion • Linear Synchronous Motor (LSM) • Used for Low-Speed Urban Maglev Program • Allows for large air gap ~ 25 mm • Varied 3-phase frequency and current for contols • Solid copper cables and laminated iron rails • Works with Halbach array

19. Propulsion • Linear Induction Motor (LIM) • Typically electromagnets in train • Aluminum ladder as track • Levitation and propulsion aquired

20. Propulsion • Modified Linear Induction Motor (LIM) • Synchronized electromagnets • Precision sensing required • Controled via the current • PWM • Current Level

21. Controls • Properties to Control • (80515 Microcontroller Based) • Levitation Hieght • Direction • Velocity

22. Controls • Levitation Height Control • Theory of current Low-Speed Urban Maglev Program • Height by causing a phase shift • Compromises the structure

23. Controls • Direction and Velocity Control • Modified Induction Motor (LIM) • Sensing and Electromagnets

24. Train Control System Train:Levitation Guidance Propulsion Mode of Operation Velocity or Current LCD • Controls • Direction and Velocity Control • Inputs: • Mode of Operation • Velocity or Current • Outputs: • Train Levitation • Train Propulsion • LCD Display

25. Train Control System Train:Levitation Guidance Propulsion Mode of Operation Velocity or Current LCD • Controls • Direction and Velocity Control • Modes of Operation: • 0.) Open Loop Backwards Current Input1.) Closed Loop Backwards Velocity Input with Control2.) Backwards Coast with No Propulsion3.) Stop4.) Forwards Coast with No Propulsion5.) Closed Loop Forwards Velocity Input with Control6.) Open Loop Forwards Current Input

26. Current Converter Direction Position Detector E-Magnet Addresser Track E-Magnets Track/ Train Sensor Addresser Track Sensors Velocity Calculation Velocity Sensor Output Controls Free Running Position Detector Inputs: Current Direction Addressed Sensor Outputs: Addresses Senosr Addresses Electromagnets Velocity

27. Current Level Current Converter Position Detector Controls Open Loop Modes 0 & 6 Inputs: Current Level Direction Outputs: Current

28. Desired Velocity Current Adjuster Current Converter Position Detector Velocity Controls Closed Loop Modes 1 & 5 Inputs: Velocity Direction

29. Controls • Coast Modes 2 & 4 • Direction is indicated for sensor prediction • Utilizes free running position detector with no current • Velocity still displayed • Stop Mode 3 • Pulse electromagnets in front of train • Position detector can not be used • Details have not been worked out

30. Controls • High Power DC Switching Current Control • Power MOSFET • Insulated -gate bipolar transistor (IGBT) • Gate-turn-off thyristor (GTO)

31. Controls Current Converted Converts current levels 0 - 256 (0-FF hex) to increasing current levels using PWM and resistor paths

32. Controls Magnet Addresser Directs current to each individual electromagnet using an array of switches for each section, and corresponding placement in each section.

33. Physical Design Materials Wood and 1/16” Aluminum

34. Testing • Inductrack Testing • Use of a horizontal or lateral wheel • Utilized by Post

35. Theories • Disk Method • Wheel Method • Tractor Tread Method • Paddle Wheel Method

36. Standards Table of standards used by the Low-Speed Urban Maglev Program Will be used for concepts to keep in mind

37. Patents Richard F. Post Magnetic Levitation System for Moving Objects U.S. Patent 5,722,326 March 3, 1998 Richard F. Post Inductrack Magnet Configuration U.S. Patent 6,633,217 B2 October 14, 2003 Richard F. Post Inductrack Configuration U.S. Patent 629,503 B2 October 7, 2003 Richard F. Post Laminated Track Design for Inductrack Maglev System U.S. Patent Pending US 2003/0112105 A1 June 19, 2003 Coffey; Howard T. Propulsion and stabilization for magnetically levitated vehicles U.S. Patent 5,222,436 June 29, 2003 Coffey; Howard T. Magnetic Levitation configuration incorperating levitation, guidance and linear synchronous motor U.S. Patent 5,253,592 October 19, 1993 Levi;Enrico; Zabar;Zivan; Air cored, linear induction motor for magnetically levitated systems U.S. Patent 5,270,593 November 10, 1992 Lamb; Karl J. ; Merrill; Toby ; Gossage; Scott D. ; Sparks; Michael T. ;Barrett; Michael S. U.S. Patent 6,510,799 January 28, 2003

38. Schedule Tentative schedule: Weeks 1 – 4 Development and testing of tracks Weeks 5 – 8 Development of a propulsion method Weeks 9 – 10 Integration of the propulsion and the Inductrack Weeks 11 – 13 Propulsion Controls Week 14 Finish Loose Ends Based on progress, meetings with Dr. Anakwa will determine the direction the project will take after each step

39. Parts and Equipment 40 - 1/2” NdFeB, Grade 38 Cubes $90.00 40 - 1/4” NdFeB, Grade 38 Cubes $14.40 Litz-wire Bulks, Copper Sheets, Aluminum Sheets, Wheels, Conductive balls, and Electromangets Cart/Train non inductive materials and CNC router machine time provided by Midwestern Wood Products Co.

40. Resources • Many Documents by Richard F. Post (LLNL) • General Conversation with Richard F. Post (LLNL) • General Conversation with Phil Jeter (General Atomics) • General Conversation with Hal Marker (Litz-wire) • General Converastion with Dr. Irwin (Bradley University)