With a peak AC current at 415 kA and a peak DC current at 385 kA, the ITER power supply test facility at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) set a new record on 2 December 2013, demonstrating its capability to host the demanding short circuit test for ITER power converters.
The facility, under construction since 2008, consists of three test platforms that can support the AC short circuit test up to 350 kA, the DC multifunction test up to 400 kA and 2 kV and a steady state test up to 60kA/1.35 kV.
The three platforms can perform all the tests required for qualifying the ITER poloidal field power converters, including rated current tests, short circuit current tests, temperature rise tests and control/protection/operation verification. In addition, they are able to provide a wide range of regulated current and voltage for the different purposes of the tests.
Moreover, the facility can host the installation of an entire poloidal field converter unit and operate it in different modes to simulate real ITER operation.
The test facility has already started accompanying the development of the ITER poloidal field converter prototype components. Several types of tests have been run, including the short-circuit (175 kA) and temperature rise (28 kA/4 hr) tests of the DC reactor; the short circuit withstand (350 kA/100 ms) and thermal stability (140 kA/2 s) tests of the enclosed AC busbar; and the short circuit withstand (350 kA/100 ms) and temperature rise (55 kA) tests of the DC disconnector. The short circuit withstand (350 kA) and the current balance tests of the converter bridge and external bypass will be performed soon.
Two large concrete pumps, one equipped with a 58-metre extensible arm (the largest available in France), were mobilized to fill a 500 square-metre area with specially formulated concrete produced in the nearby batching plant.
Operations began at 4:00 a.m. and continued for 10 hours. This was the second segment (out of 15) poured for the Tokamak Complex basemat, and one of three that will support the future ITER Diagnostics Building.
Special measures were set into place to counter the early morning cold, such as producing warm concrete in the batching plant (by heating the water and gravel) and using plastic sheeting as the work progressed to avoid too rapid cooling.
Hot air blowers were also activated once the pour was complete to regulate the drying process.
The complete Tokamak Complex basemat (1.5-metre-thick) is scheduled to be in place in July. Work will resume next week on the rebar installation in the central area of the Tokamak Pit.
The European Domestic Agency for ITER, Fusion for Energy, started the new year with the completion of an important milestone linked to Europe’s contribution to ITER: the successful manufacturing of the cryopanels and thermal shields for the Pre-Production Cryopump (PPC).
The Pre-Production Cryopump will be the spare for ITER’s eight cryopumps (two in the cryostat and six in the torus). The cryopumps will be constantly operational and will play a vital role in the production of the ultra-high vacuum inside the vacuum vessel. In a nutshell, these components will help attain optimum plasma performance.
After an intense period of research, development and design, Fusion for Energy was entrusted with the responsibility of manufacturing the components. In November 2012, a series of contracts were signed with four companies based in Germany and in France, as well as with the Karlsruhe Institute of Technology (KIT) for the manufacturing of the Pre-Production Cryopump.
The Pre-Production Cryopump and the rest of the torus cryopumps will operate with helium at 3.5 K (-269.5ºC). They consist of the cryopanels, which perform the pumping action, and thermal shields that protect the cryopanels from excessive thermal loads. The components were put through complex dimensional controls and ultra-high vacuum leak tests.
The cryopanels have already been delivered to KIT and the thermal shields to Research Instruments, a German company that will integrate the manufacturing activities. At KIT, the cryopanels will be sprayed with charcoal, which is necessary for the pumping of helium and hydrogen isotopes from the torus. Research Instruments, together with Alsyom/Seiv will play a pivotal role in the production of the rest of the cryopump components, assembly, as well as the final cold ultra-high vacuum leak tests for the Pre-Production Cryopump.
Read the full article here.
The Centre de Recherches en Physique des Plasmas (CRPP) in Switzerland has studied fundamental plasma physics since 1961, with a particular focus on magnetic fusion since 1979. Part of the Ecole Polytechnique Fédérale de Lausanne (EPFL), the CRPP operates the TCV tokamak and the SULTAN facility for testing and evaluating high current superconductors. We recently spoke with Pierluigi Bruzzone, head of CRPP’s Superconductivity section, about work currently underway at SULTAN for the ITER magnets.