Download Project Proposal Presentation (12/09/03)

BRADLEY UNIVERSITY
Department of Electrical and Computer Engineering
Sr. Capstone Project
Advisor:
Dr. Anakwa
Student:
Paul Friend
Overview:
•Background Information •Controls
•Halbach Array
•Physical Design
•Inductrack
•Theories
•Sensors
•Parts and Equipment
•Propulsion Methods
•Schedule
•Resources
Background Information
Inductrack:
•Created by Richard F. Post in the late 1990’s at
Lawrence Livermore National Laboratory
•20 meter test track
•Burst Propulsion
Background Information
Inductrack:
•Contracted by NASA for Satellite Launcher
•Low-Speed Urban Maglev Program
Halbach Array
•Created by Klaus Halbach
•Creates a strong, nearly one-sided magnet with a
sinusoidal field by directing the magnetic fields.
Halbach Array
•Standard Formation
•Expanded Wavlength
•Doubled Method
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]
Inductrack
Basic Methods:
•Array of Inductors
•Laminated Copper
•Laminated Aluminum
Inductrack
Array of Inductors
•Used in 1st Inductrack
•Insulated Litz-wire
•Ferrite Loading
Inductrack
Laminated Copper
•Square Litz-wire bulks
•Used for Low-Speed Urban Maglev Program
Inductrack
Laminated Copper & Aluminum
•Thin Sheets
•Slots cut to guide eddy currents
•Slots terminated at ends for “shorts”
Inductrack
Physics
•Lenz’s Law
•Discovered in 1834
•Eddy currents created due to moving magnetic field
•(Not guided)
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]
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
Inductrack
Inductrack II
Sensors
Types:
•Velocity Sensor
•Optical Sensor
•Magnetic Sensor
Propulsion
Types:
•Linear Synchronous Motor (LSM)
•Linear Induction Motor (LIM)
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
Propulsion
Linear Induction Motor (LIM)
•Typically electromagnets in train
•Aluminum ladder as track
•Levitation and propulsion aquired
Propulsion
Modified Linear Induction Motor (LIM)
•Synchronized electromagnets
•Precision sensing required
•Controled via the current
PWM
Current Level
Controls
Properties to Control
(80515 Microcontroller Based)
•Levitation Hieght
•Direction
•Velocity
Controls
Levitation Height Control
•Theory of current Low-Speed Urban Maglev Program
•Height by causing a phase shift
•Compromises the structure
Controls
Direction and Velocity Control
•Modified Induction Motor (LIM)
•Sensing and Electromagnets
Controls
Direction and Velocity Control
•Inputs:
Mode of Operation
Velocity or Current
•Outputs:
Train Levitation
Train Propulsion
LCD Display
Mode of
Operation
Velocity or
Current
Train Control
System
Train:
Levitation
Guidance
Propulsion
LCD
Controls
Direction and Velocity Control
Modes of Operation:
0.) Open Loop Backwards Current Input
1.) Closed Loop Backwards Velocity Input with Control
2.) Backwards Coast with No Propulsion
3.) Stop
4.) Forwards Coast with No Propulsion
5.) Closed Loop Forwards Velocity Input with Control
6.) Open Loop Forwards Current Input
Mode of
Operation
Velocity or
Current
Train Control
System
Train:
Levitation
Guidance
Propulsion
LCD
Controls
Free Running Position Detector
Inputs:
Current
Converter
Current
Direction
Direction
Position
Detector
Addressed Sensor
Outputs:
Velocity
Addresses Senosr
Addresses Electromagnets
Velocity
Velocity
Calculation
E-Magnet
Addresser
Track
E-Magnets
Sensor
Addresser
Track
Sensors
Sensor
Output
Track/
Train
Controls
Open Loop Modes 0 & 6
Inputs:
Current Level
Direction
Outputs:
Current
Current
Level
Current
Converter
Position
Detector
Controls
Closed Loop Modes 1 & 5
Inputs:
Velocity
Direction
Desired
Velocity
Current
Adjuster
Current
Converter
Position
Detector
Velocity
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
Controls
High Power DC Switching Current Control
•Power MOSFET
•Insulated -gate bipolar transistor (IGBT)
•Gate-turn-off thyristor (GTO)
Controls
Current Converted
Converts current levels 0 - 256 (0-FF hex) to increasing current
levels using PWM and resistor paths
Controls
Magnet Addresser
Directs current to each individual
electromagnet using an array of
switches for each section, and
corresponding placement in each
section.
Physical Design
Materials
Wood and 1/16” Aluminum
Testing
Inductrack Testing
•Use of a horizontal or lateral wheel
•Utilized by Post
Theories
•Disk Method
•Wheel Method
•Tractor Tread Method
•Paddle Wheel Method
Standards
Table of standards used by the Low-Speed Urban Maglev
Program
Max. Speed
Throughput
Max Acceleration
Min Curve Radius
Max Grade
160 km/hr
12000/hr/direction
1.6 m/s2
18.3 m (60 ft.)
10%
Max Jerk
Inside Noise Level
DC Mag. Field in Car
Availability
Ride Quality
Will be used for concepts to keep in mind
2.5 m/s3
< 67 dB
< 5 Gauss
> 99.99%
ISO 2631 (1987)
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
Schedule
Tentative schedule:
Weeks 1 – 4
Weeks 5 – 8
Weeks 9 – 10
Weeks 11 – 13
Week 14
Development and testing of tracks
Development of a propulsion method
Integration of the propulsion and the
Inductrack
Propulsion Controls
Finish Loose Ends
Based on progress, meetings with Dr. Anakwa will determine the
direction the project will take after each step
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.
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)