View Now

The Influence of Outbreak Magnetic Field by
a Superconducting Magnet for
the surrounding devices and environment
High Energy Accelerator Research Organization(KEK) / Tesuya Yokoo, Ph.D
Tohoku University / Kenji Ohoyama, Dr.Sci
ANSYS Japan / Takahiro Koga
Agenda
1. Background
2. Motivation
3. Electromagnetics Analysis
4. Vector Hysteresis Modeling
5. Simulation Model
6. Simulation Results
7. Conclusion
2
Background
Tohoku University and KEK joint project
3
Background
4
Background
5
Background
6
Motivation
• For the under constructing large-scale experimental
devices and laboratory, the outbreak magnetic field by the
Superconducting Magnet (7 tesla) may adversely affect
the environment/system.
• Perform visualization by electromagnetic simulation for
remanence magnetization.
• Precision Goal: 10 tesla ~ 10uT order (100,000~0.1 gauss)
* Earth magnetism: 46uT (Japan)
7
Remanence Magnetization
Permanent
Magnet
Hysteresis Loop
J
Iron
H
J
Wide
Soft/Hard Magnetic Material
H
J
Iron
Permalloy
H
Narrow
Soft Magnetic Material
8
Electromagnetics Analysis
ANSYS Maxwell
Applications
 Motor
 Actuator
 Coil, Inductor
 Transformer
 RFID
 Induction Heater
 Permanent Magnet
 Sensor
 Capacitor
 Electrode
9
Vector Hysteresis Modeling
• ANSYS Maxwell has a capability to handle
major/minor BH hysteresis loop simulation
by transient solver
• Remanence magnetic field at soft magnetic material
Soft magnetic core
Input Current waveform
Tracking BH Operating point
10
Simulation Model
• Magnetic Analysis
– Superconducting Magnet
– Magnetic Devices (Beam Line Devices)
– Laboratory Model
11
Superconducting Magnet
• Target Point: 6.83 tesla
12
Superconducting Magnet
6.83T @ 0 m
10mT @ 1 m
1mT @ 2 m
0.7T @ 0.5 m
Source
Far
Mag_B vs. Distance from magnetic source
13
Magnetic Devices (Beam Line Devices)
Guide Magnet3
Helmholtz Coil
Guide Magnet2
Guide Magnet1
Solenoid Coil
2.4m
Beam
Line
Posted with Superconducting Magnet
14
Magnetic Devices (Beam Line Devices)
Magnet Guide3
Helmholtz Coil
Magnet Guide2
Magnet Guide1
Solenoid Coil
Hci = 4 [A/m]
Wrapping Permalloy Sheet
Expanded H
Permalloy BH curve
15
Magnetic Devices (Beam Line Devices)
Helmholtz Coil
Magnet Guide3
Magnet Guide2
Steel Board
Permanent magnet (NdFeB)
Magnet Guide1
Solenoid Coil
Hci = 53 [A/m]
Expanded H
Steel BH curve
16
Laboratory Model
http://nc-imr.imr.tohoku.ac.jp/instruments.html
http://j-parc.jp/researcher/MatLife/ja/instrumentation/ns.html
17
Laboratory Model
12meter
2.4m
4.3meter
23meter
18
Laboratory Model
Major Structure Materials
Iron (SS400)
Stainless
Concrete
Hci = 80 [A/m]
Expanded H
SS400 BH curve
19
Input Current
Compared before/after magnetic field
by the influence of remanence with
the Superconducting Magnet
Solenoid Coil
Helmholtz Coil
Superconducting Magnet
Before
Outbreak
After
20
Simulation Results
• B Vector plot on Beam Line
• Magnetic Field around Beam Line devices
• Magnetic Field at Laboratory
21
B Vector Plot on Beam Line
Beam
Line
• Before/After Bx, By, Bz plot
• Devices: No input current
Y Scale: -1 ~ 1 Gauss
Y Scale: -1 ~ 1 Gauss
Y Scale: 0 ~ 450 Gauss
Bx
By
Max. Delta: 0.31 Gauss
Max. Delta: 0.071 Gauss
(
：Before ／
Bz
Max. Delta: 2.68 Gauss
：After)
22
B Vector Plot on Beam Line
• Before/After Bx, By, Bz plot
• Devices: No input current
Y Scale: 0 ~ 30 Gauss
Beam
Line
Bz
Max. Delta: 2.68 Gauss
(
：Before ／
：After)
23
Magnetic Field around Beam Line devices
Before
After
24
Magnetic Field around Beam Line devices
* Log Scale
Before
* Log Scale
After
25
Magnetic Field around Beam Line devices
Outbreak
After
26
Magnetic Field around Beam Line devices
B Vector Field
27
Magnetic Field Laboratory
Structure under the floor
Outbreak
After
28
Magnetic Field Laboratory
Side Wall
Outbreak
After
29
Magnetic Field Laboratory
YZ Cross Planes
Scale ~100 Gauss
Scale ~100 Gauss
Before
After
30
Magnetic Field Laboratory
XY, XZ Cross Planes (After)
Scale ~100 Gauss
Scale ~10 Gauss
After
After
31
Magnetic Field Laboratory
Beam Line – Emitting Port
Scale ~10 Gauss
Before
After
32
Beam Line – Emitting Port
Iron structure
Stainless structure
Should be change stainless
33
Conclusion
• We succeed to analyze and visualize the influence of outbreak
magnetic field, remanence magnetized soft magnetic material by a
Superconducting Magnet with ANSYS Maxwell’s Vector Hysteresis
Modeling.
• Magnetic devices on beam line would be magnetized, but not affect.
• Beam emitting port might influence the beam control by remanence
-> Need to change design to non-magnetic material e.g. stainless
• Contribute to investigate the prior validation for the large-scale
experimental device under construction.
34

Download Report