max-planck institut für plasmaphysik
DESCRIPTION
Max-Planck Institut für Plasmaphysik. Construction of Wendelstein 7-X Hans-Stephan Bosch Max-Planck-Institut für Plasmaphysik Greifswald. Institute of Plasma Physics , CAS, Hefei, October 18, 2010. Stellarator Wendelstein 7-X. Optimisation criteria small neo- classical transport - PowerPoint PPT PresentationTRANSCRIPT
Max-Planck Institutfür Plasmaphysik
Construction of Wendelstein 7-X
Hans-Stephan Bosch
Max-Planck-Institut für PlasmaphysikGreifswald
Institute of Plasma Physics, CAS, Hefei, October 18, 2010
2
Stellarator Wendelstein 7-X
Modular stellarator,
Superconducting coils
Fully optimized numerically
Optimisation criteria small neo-classical transport good confinement of fast particles minimised bootstrap current good MHD stability good finite b-equilibria feasible modular coils
4
W7-X, plasma
Pentagon-shaped 5 identical modules, each made of 2 flip-symmetric half-modules
5
W7-X, divertor
10 separate divertor units 2 in each of the 5 modules designed for a maximum heat load of 10 MW/m2
6
W7-X, in-vessel components
Target modules10 units: 7210 kg
Glow discharge electrode10 units
Port protection (optional)100 m2: 3127 kg
Cryo-vacuum-pumps10 units: 600 kg
Wall protection + piping62 m2: 5527 kg
Poloidal closure10 m2: 634 kg (panel type)
Protection of divertor aperture10 m2: 634 kg
Toroidal shielding5 m2: 608 kg (baffle type)
Plug-ins, water pipes4000m, 3583 kg
Baffle modules10 units: 6115 kg
Heat shield (high loaded)47 m2: 4280 kg
Plasma vessel
Control coils10 units: 1450 kg
Two step approach requires intermediate components:• Inertial cooled divertor (TDU) for first operation phase• Actively cooled high-heat-flux (HHF) divertor for steady state phase
7
W7-X, in-vessel components, status
heat shields • structure in manufacturing • The graphite tiles are also in manufacture
Target plates • prototypes finished• manufacturing started
wall panels• all 320 panels have been delivered by MAN DWE (Germany)
8
W7-X, plasma vessel
volume 110 m3
surface200 m2
mass 33 t vacuum < 10-8 mbar baking up to 150o C tolerances < 2 mm
9
W7-X, plasma and plasma vessel
20 welded rings per half-module
Multi-Layer Insulation 20 layers of crinkled Kapton
foil glass mats in betweenThermal shield glass fibre panels, Al coated Cu braids for connection to water cooling
10
W7-X, magnet system
magnetic field in plasma 2.5 T (< 3T)
magnetic field energie 600 MJ NbTi superconductor (>3.4 K) 50 non-planar coils (5 types) 20 planar coils (2 types)
BNN, G / Ansaldo, I / Tesla, GB
11HSB, 22.10.09
NbTi superconductor for W7-X
cabling
243 single fibres (3 x 3 x 3 x 3 x 3)
Cable-in-Conduit (Coextrusion)In up to17.6 kA
fibreNbTi with Cu
0,58 m
12HSB, 22.10.09
Wendelstein 7-X, coil fabrication I
Tempering of cast casing /half shell(Österby, Sweden)
Coil winding(ABB, Augsburg)
13
Wendelstein 7-X, coil fabrication II
Assembly of winding pack in casing
Overview ofproduction hall
(BNN, Zeitz)
14
Wendelstein 7-X, superconducting coils
15HSB, 22.10.09
Wendelstein 7-X, Cryogenic testing of coils
CEA Saclay, France:• Tests at 5K• Thermal properties• Cold leak tightness• Helium flow rates• Electrical insulation• Superconductivity
16HSB, 22.10.09
Wendelstein 7-X, Paschen testing of coils
• critical scenario: air influx into cryo vacuum causes pressure increase and quench of a coil High voltage @ high pressure Paschen discharge possible • Therefore all coils are tested under Paschen conditions (between 0.001 and 100 mbar) with 6 kV• This has proven to be a valuable measure to verify insulation quality.
17
W7-X, support structure
welded ring in 10 half-modules mass: 71 t Support of all coils, high
precision extensive inter-coil support structure to prevent movement of coils
Ensa, Spain
18
W7-X, support structure
19
W7-X, outer vessel and ports
volume 525 m3
surface 480 m2
mass 170 t vacuum < 10-5
mbar number of ports 254
DWE, Germany
Romabau,Switzerland
ROMABAU
20
W7-X, outer vessel and ports
All 5 modules delivered Installation of Thermal Insulation ongoing
21
W7-X, pre-assembly
Coils are threaded across the plasma vessel
Thermal insulation is completed
• The coil support structure is positioned in front of the 7-coil pack• Coils are bolted to the central support ring
22HSB, 22.10.09
W7-X, pre-assembly II
• The flip-symmetric half-modules are aligned• The step-flange is bolted and the vessel half-modules are welded• Thermal insulation, Inter-coil structure are completed
23
W7-X, assembly
Module 5, February 2009
24
W7-X, torus hall October 13, 2009
25
W7-X, 1. module inserted in cryostat lower shell, 29.10.09
26
W7-X, first upper shell of cryostat, 25.11.09
27
W7-X, 3. module on machine base, 18.08.10
28
W7-X, Assembly of ports in 1. module, 27.09.10
29
Assembly schedule
• Assembly of the five modules is running in parallel• All 5 modules are in the works at present• Major “new” work packages:
- module connection- diagnostics- in-vessel assembly
• The assembly schedule still contains half a year buffer times• Assembly will be finished in summer 2014
- periphery installations
30
Operations planning
• stepwise approach• 1st operation phase with 10s @ 8MW, inertially cooled
divertor and only partial cooling of in-vessel components• shut-down (15 months) for completion and hardening• 2nd operation phase to approach 30min @ 10MW