Please cite this article in press as: M. Boldrin, et al., Final design of the High Voltage Deck 1 and Bushing for MITICA: The ITER Heating Neutral Beam Injector prototype, Fusion Eng. Des. (2017), http://dx.doi.org/10.1016/j.fusengdes.2017.03.133 ARTICLE IN PRESS G Model FUSION-9314; No. of Pages 5 Fusion Engineering and Design xxx (2017) xxx–xxx Contents lists available at ScienceDirect Fusion Engineering and Design journal homepage: www.elsevier.com/locate/fusengdes Final design of the High Voltage Deck 1 and Bushing for MITICA: The ITER Heating Neutral Beam Injector prototype Marco Boldrin a,∗ , Tullio Bonicelli b , Hans Decamps c , Claudio Finotti a , Elena Gaio a , Gerard Escudero Gomez b , Michael Krohn d , Edgar Sachs d , Muriel Simon b , Vanni Toigo a a Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova, Italy b Fusion For Energy, c/Josep Pla 2, 08019 Barcelona, Spain c ITER Organization,Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex, France d Siemens AG,Process Industries and Drives Division, Large Drives, Industrial Applications PD LD AP S TA EL, Gleiwitzer Str. 555, 90475 Nürnberg, Germany h i g h l i g h t s • HVD1 and HVBA are unique devices for size, electrostatic and mechanical features. • Main design choices to satisfy the challenging technical requirements are presented. • The supporting electrostatic, seismic and thermal analyses are reported. • Next procurement steps and tests to verify the key design choices are also reported. a r t i c l e i n f o Article history: Received 26 September 2016 Received in revised form 20 March 2017 Accepted 22 March 2017 Available online xxx Keywords: ITER Heating Neutral Beam Injector (HNB) High voltage deck 1 (HVD1) High Voltage Bushing Assembly (HVBA) Insulation design Seismic design Thermal design a b s t r a c t The Ion Source of the ITER Heating Neutral Beam Injector (HNB) is polarized at −1MVdc to ground. A large-1MVdc air-insulated Faraday cage (12.5 m (L) × 8.4 m (W) × 9.6 m (H)), called High Voltage Deck 1 (HVD1), hosts the Ion Source and Extractor Power Supplies (ISEPS) and the associated HNB diagnostics; the HVD1 is interfaced with a SF 6 insulated Transmission Line (connecting the main power supplies to the HNB) through a High Voltage (HV) Bushing Assembly (HVBA) carrying inside ISEPS power conductors and diagnostics. The HVD1 and HVBA are unique devices for size, electrostatic and mechanical features. This paper presents the main design choices adopted to comply with the challenging technical require- ments and the supporting electrostatic, seismic and thermal analyses. Finally, next procurement steps and definition of special tests to verify the key design choices are also reported. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Two Heating Neutral Beam Injectors (HNBs) will be installed in ITER, designed to deliver to the plasma a power up to 16.5 MW each, with a pulse lasting up to 1 h [1]. The realization and future oper- ation of ITER HNB is very demanding both from engineering and physics point of view. For this reason, a full scale HNB prototype called MITICA (Megavolt ITER Injector & Concept Advancement) is being built at the Consorzio RFX premises in Padua (Italy), hosted in a test facility called PRIMA (Padua Research on Injector with Mega- volt Acceleration) [2]; its design has been developed with the aim ∗ Corresponding author. E-mail address: marco.boldrin@igi.cnr.it (M. Boldrin). to be as close as possible to that one for ITER so as to validate the technological choices and benefit of the feedbacks from the com- missioning and first operation. The Power Supply (PS) system is very complex, too. To solve some issues related to the accessibil- ity for maintenance and feasibility of the implementation of the RF driven Ion Source it was chosen to host the Ion Source and Extrac- tor Power Supplies (ISEPS) [3] in a large air insulated platform [4], called High Voltage Deck 1 (HVD1), hosted inside a High Voltage Hall (HVH). The connection from the HVD1 to the SF 6 insulated Transmission Line (TL) is provided by a High Voltage (HV) Bush- ing Assembly (HVBA, see Fig. 1) carrying inside ISEPS power and diagnostics conductors. The HVD1 and the HVBA are unique components in terms of size and complexity. The main challenges of their design are the very high electric insulation (the maximum voltage level for indus- http://dx.doi.org/10.1016/j.fusengdes.2017.03.133 0920-3796/© 2017 Elsevier B.V. All rights reserved.