7.6
Test Facilities and SC Magnets Tests
WU Yu
7.6.1 Test Facilities
Test Facilities has been built in 1999, its primary goal is to test the EAST TF and PF
magnets performance of electromagnetic, stability, thermal and hydraulic, mechanical. The
Facilities is located at Institute of Plasma Physics. A helium refrigerator is used to cool
magnets and liquefy helium which can provide 3.8-4.5K, 1.8-5bar, 20-40g/s supercritical
helium for coil or 150 liter/hr liquefying helium capability. Other major parts are a large
vacuum vessel (3.5m diameter and 6.1m height) with liquid nitrogen temperature shield,
two pairs of current lead, two kinds of 14.5-50 kA power supply with fast dump quench
protection circuitry, data acquisition and control system, vacuum pumping system and gas
tightness inspecting devise.
Specific function of Test Facilities include the follow activities:
Mounting the superconducting magnet in the test facilities
Pre-cooling the magnet under test
Establishing a supercritical helium cooling flow in the magnet under test
Inspecting gas tightness of coils and case at room temperature and liquid helium
temperature
Fig.1
Test Facilities Overview
Operating the magnet with a test current profile ,continuous or pulsed
Measurements of temperatures, heat loading, helium pressure and flows, strains,
liquid levels, magnet currents, magnetic field intensities and other important parameters of
magnet
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Taking automatic logs of data and measurements
Warming the magnet back to an ambient temperature
Removing the magnet from the test facilities
Test Facilities consists of a vacuum cryostat, helium cooling system, LN2 cooling
system, power supply system and control system, quench diagnosing and fast energy
released system. These sub-systems include the following components:
A test vacuum chamber to set the test objects
Liquid nitrogen cooled thermal shielding with multi-wall adiathermal material
between vacuum chamber and Liquid nitrogen shielding
Thermally insulating mechanical supports to hold the weight of the test objects
Four pulling poles to keep balance of TF magnet
Removable connections for supercritical helium cooling loops
Thermally insulating current leads with active cooling
Cryogenic insulators for liquid helium connections
Easy unweaving CICC joints for current connecting of magnet
Forced flow helium cooling loop including cold box, heat exchanger, jet, valves
Helium liquefier system
Helium purifying device
Liquid helium reservoir
Helium gas recovery system
Liquid helium interconnecting lines
Power supplies
Instrumentation (flow, temperature, pressure, strain, liquid level, current, magnetic
field, voltage ) and display electronics
Control system
Data acquisition system
7.6.2 SC magnets test
The Central Solenoid model coil has been tested in 2001 and 2002, TF prototype
magnets was tested at the beginning of 2003.Each test we want to get two main results: one
is the performance of magnet, the other is the performance of all sub-system and devices of
test facilities. Now some tests and measurements have been carried, those are as followed:
Electromagnetic, stability, thermal and hydraulic, mechanical performance of
central solenoid model coil
Forced flow helium cooling loop including cold box, heat exchanger, jet, valves
Capability of helium refrigerator
Resistance of easy unweaving CICC joints
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the
Quench diagnosing and fast energy released
Mechanical Performance of magnetic support Platform
Performance of cryogenic insulators
Liquid helium consuming ratio of current leads at zero current
Rectifying supercritical helium flows
Gas tightness inspecting of coil, case, helium loops and LN2 shielding
Temperature control of LN2 shielding
Data acquisition system and control system
Some test and measurement results are shown as follows:
Fig.2 CSMC setting up in vacuum cryostat
Fig.3 CSMC temperature during test
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Fig.4 CSMC pressure during test
Fig.5 CSMC flow during test
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12
current(kA)
10
40
Current
B1
35
ramp rate 300A/S
drop rate 2.33T/S
30
25
8
20
6
15
4
magnetic field(kG)
14
10
2
5
0
0
0
20
40
60
80
100
120
time(S)
Fig.6 CSMC fast charge and fast discharge
8
6.6
7
6.5
6
6.4
Current(kA)
T3
T4
T5
4
3
6.2
6.1
6.0
2
5.9
1
ramp rate 400A/S
drop rate 400A/S
0
5.8
5.7
19:22
19:24
19:26
19:28
19:30
19:32
19:34
Time(hh::mm)
Fig.7 CMSC AC-loss test
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19:36
19:38
19:40
Temprature(K)
Current
6.3
5
Fig.8
TF magnet temperature during test
Fig.9
TF magnet flow during test
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