Installation and site testing of the SPIDER Ion Source and Extraction Power Supplies

SPIDER experiment, currently under construction at the Neutral Beam Test Facility (NBTF) in Padua, Italy, is a full-size prototype of the ion source for the ITER Neutral Beam (NB) injectors part of the ITER project. The Ion Source and Extraction Power Supplies (ISEPS) for SPIDER are supplied by OCEM Energy Technology s.r.l. (OCEM) under a procurement contract with Fusion for Energy (F4E) covering also the units required for MITICA and ITER injectors. The installation of SPIDER ISEPS started in June 2015 and was completed in September 2015. Functional checks started thereafter and power testing in January 2016. The formal Site Acceptance Tests (SAT), witnessed by F4E, Consorzio RFX and the ITER Organization were successfully completed in April 2016. ISEPS, with an overall power rating of 5 MVA, form a heterogeneous set of items, ranging from power transformers, medium voltage power distribution equipment at 6.6 kV to solid state power converters and including four 1 MHz radiofrequency generators of 200 kW output power. Both high voltage, down to -12 kV and high current, up to 5kA, power supplies are present. The paper presents the main features of the SPIDER ISEPS installation inside the SPIDER HV Deck, focussing in particular on non-standard technical solutions like the cable terminations on the HV Deck incoming power lines. The arrangements are described for fully checking the integration of the ISEPS local control system with the SPIDER control system are described. Details are given on non-standard site tests verifying immunity to electromagnetic interference (EMI) and the behaviour of the control electronics during fast discharges of electrostatic energy, specific to this application. Performance of ISEPS during the SAT is described and commented against the specifications, with emphasis on demonstration of the 1 hour full load capability of the radiofrequency generator.