The first F4E component for the Neutral Beam Test Facility (NBTF), the SPIDER High-Voltage Deck (HVD), has been delivered and accepted at the NBTF at the Consorzio RFX site in Padua, Italy.
F4E have collaborated with the Italian company COELME in order to design, manufacture and install the HVD, a mechanical structure which will hold the set of power supply equipment weighing around 40 tonnes. The delivery and acceptance of the HVD marks the end of a four-month installation period. Each individual sub-component has undergone several checks and tests before performing the final electric tests for the whole HVD. Since the testing involved high voltage conditions (reaching up to 130 kV), it was important from a safety point of view to also ensure that the area was properly isolated and that all present at the testing were properly briefed about safety coordination.
“This is a major achievement”, said Daniel Gutierrez, F4E Technical Officer. “We are especially pleased because we have not faced any major problems during installation or testing and everything has been carried out in accordance with our planned time schedule”, he added. “The HVD is now ready to host the Ion Source and Extraction Power Supplies (ISEPS) which are necessary for feeding the ion source of the Neutral Beam injector”.
The ion source produces ions (particles with electric charges – either positive or negative), from which neutral particles originate. The neutral particles will be injected in the ITER plasma in order for the plasma to obtain the temperature and conditions necessary for the fusion reaction to occur. The NBTF will house two independent test beds, namely SPIDER (Source for Production of Ion of Deuterium Extracted from Radio frequency plasma), where the first full-scale ITER ion source will be tested and developed with an acceleration voltage up to 100 kV; and MITICA (Megavolt ITER Injector and Concept Advancement) which will be the first 1:1 full ITER injector aiming at operating up to the full acceleration voltage of 1 MV and at full power (16.5 MW). F4E will supply the ITER machine with two neutral beam (NB) injectors (i.e. two similar injectors such as in MITICA).
The HVD is a vital component for the SPIDER experiment. It measures approximately 13 × 11 metres, the HVD is installed in a pit around 1 metre below ground-floor level, and is mounted on supporting insulators so that it can withstand the high 100 kV voltage of the power supplies. The HVD is covered by a closed aluminium screen which reduces electromagnetic interference that could have a negative effect on the equipment inside and the power supply.
The acceptance of the HVD is not the end of F4E’s collaboration with COELME. The SPIDER Transmission Line (TL) is the component on which work will focus during the coming months. The TL will connect the power supplies installed inside the HVD to the SPIDER ion source and beam acceleration. Measuring around 30 metres in length, the Transmission Line uses unique double-screening sandwich panels which give extra protection against electromagnetic interference. The manufacturing stage of the TL will come to an end by November this year and its site installation is expected to start before the end of 2015.