@inproceedings{oai:repo.qst.go.jp:00074739,
 author = {De Lorenzi, Antonio and Pilan, Nicola and Chitarin, Giuseppe and 柏木, 美恵子 and 小島, 有志 and 梅田, 尚孝 and 戸張, 博之 and P.L. De Esch, Hubert and Svensson, Lennart and Kashiwagi, Mieko and Kojima, Atsushi and Umeda, Naotaka and Tobari, Hiroyuki},
 book = {2018 28th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV)},
 month = {Nov},
 note = {This overview summarizes the R&D activities aimed to secure for the ITER Neutral Beam Injectors a stable voltage holding, one of the most challenging issue for the NBI systems operation. The huge size of the accelerator and the highest voltage (1 MV) ever used in such systems make prominent some aspects that are, in other application, almost not influent or well under control, like the Area Effect, Total Voltage Effect, the highly complex electrostatic configuration and, last but not least, the cleaning degree of the electrodes surfaces. A clear explanation of the mechanism leading to the voltage breakdown in these conditions is far from being well established. But in the last years a great effort have been deployed by the NBI community to reliably achieve 1 MV voltage holding that is required for the NB injectors for ITER. Theoretical models and new tools have been derived to explain the mechanism of voltage conditioning and for the design of the complex electrodes geometries that supersede the simple electric field optimization. Presently, the milestone of the 1 MV voltage holding has been achieved but only with multi-gap configuration; activities are nevertheless in progress aimed to obtain a reliable single gap 1 MV voltage holding in the accelerator.},
 pages = {1--10},
 title = {HV Holding in Vacuum, a Key Issue for the ITER Neutral Beam Injector},
 volume = {2},
 year = {2018}
}