This document contains the delivery notes of task order F4E-OFC-280-04.

This document contains the Safety Integrity Level allocation of the safety instrumented functions for the MITICA Central Safety System, as defined by Consorzio RFX with the support of external contractors.

This document contains the list of safety instrumented functions for the MITICA Central Safety System as defined by Consorzio RFX with the support of external contractors.

This document contains the list of protection instrumented functions for the MITICA central Interlock.

This document contains the list of interface signals of MITICA central Interlock with plant systems.

This document contains the revised analysis of MITICA failure modes and effects.

At the ITER Neutral Beam Test Facility, the Source for the Production of Ions of Deuterium Extracted from Radio frequency plasma (SPIDER) has been in operation since 2018 aiming at prototyping the heating and diagnostic neutral beam appliances in view of the ITER demanding requirements for plasma burning conditions and instabilities control. For the sake of safety, machine protection and efficiency it is necessary to follow an accurate planning strategy and approval action of the experiment parameter settings. Although the initial tools available for the SPIDER integrated commissioning and early campaigns offered the basic functionality to perform the necessary tasks, there were a set of relevant issues that were identified as needing improvements for an efficient and safe configuration environment. Namely, the fact that there were no tools indicating the parameters change since the previous pulse, or the lack of a comparison tool between a new set of parameters and a previous setup, demanded a tedious and error prone verification of all parameters in the sequence. Moreover, several verifications should be automated according to the machine safety limits, increasing the safety check by human and automated machine (algorithmic) validation. This contribution depicts (i) the approval sequence designed for SPIDER safe operation; (ii) the configuration environment requirements according to the SPIDER pulse preparation procedure; (iii) the decision of the development tools used for implementation and design;(iv) the implementation details and preliminary tests of the global environment.

MITICA is one of the two ongoing experiments at the ITER Neutral Beam Test Facility (NBTF) located in Padova (Italy). MITICA aims to develop the full-size neutral beam injector of ITER and, as such, its Control and Data Acquisition System will adhere to ITER CODAC directives. In particular, its timing system will be based on the IEEE1588 PTPv2 protocol and will use the ITER Time Communication Network (TCN). Following the ITER device catalog, the National Instruments PXI-6683H PTP timing modules will be used to generate triggers and clocks that are synchronized with a PTP grandmaster clock. Data acquisition techniques, such as lazy triggers, will be also used to implement event-driven data acquisition without the need of any hardware link in addition to the Ethernet connections used to transfer data and timing synchronization. To evaluate the accuracy over time that can be achieved with different network topologies and configurations, a test system has been set-up consisting of a grand master clock, two PXI-6683H devices and two PTP aware network switches. In particular, the impact on accuracy due to the transparent and boundary clocks configurations has been investigated. In addition, a detailed simulation of the network and the involved devices has been performed using the OMNET++ discrete event simulator. The simulation parameters include not only the network and switches configuration, but also the PID parameters used in the clock servo controllers. A comparison between simulated and measured statistics is reported, together with a discussion on the possible optimal configuration strategies.

The negative-ion based neutral beam injector for heating and current drive of the ITER plasma (ITER HNB) is under development, at present focusing on the optimization of the full-scale plasma source in the SPIDER test stand. The production of H- or D- ions in the ion source is based on the low work function surfaces obtained by caesium evaporation. This paper describes the caesium conditioning procedure and the corresponding beam performances during the first operation of SPIDER with caesium. Technical solutions to overcome present limitations of the test stand are described. The influence of source parameters on the caesium effectiveness was investigated in short beam pulse operation; with total radio-frequency (RF) power of 400 kW and filling pressure below 0.4 Pa, and a limited number of extraction apertures, a negative ion current density of about 200 A m-2 was extracted in hydrogen, with beam energy lower than 60 keV. Beam optics and beam uniformity were assessed thanks to the acceleration of isolated ion beamlets. A possible procedure to accelerate a uniform beam was demonstrated at low RF power. The results obtained in this first investigation provided key indications on the operation of one of the largest existing sources of accelerated negative hydrogen-like ions.

The electrical insulation of the Megavolt ITER Injector and Concept Advancement (MITICA) beam source (BS) at 1 MV in vacuum is a challenging issue, which could not be fully addressed so far on the basis of experimental results and of theoretical models available in literature. A specific high-voltage (HV) test campaign is being prepared to validate and optimize the voltage holding capability of the BS insulation under realistic conditions, using full-size mockup electrodes reproducing in detail the geometry of the BS and accelerator. The proposed test strategy will address both the single-gap and the multistage insulation, so as to obtain a verification of voltage holding at 1 MV before the installation of the real components. This approach is intended to reduce the risk related to the HV insulation at 1 MV and, if necessary, to allow the development of effective corrections. In this article, the test motivations and requirements are defined, and the electrode implementation and diagnostic setup are described. Finally, the test configurations and the experimental procedure are discussed.

This document is the test plan for the MITICA commissioning campaign M-C1-C addressing the remote control mode of MITICA Cooling under miniCODAS.

This document contains the final design of the MITICA Central Interlock Network and Central Safety Network.

To reach fusion conditions and control the plasma configuration in ITER, the next step in tokamak fusion research, two neutral beam injectors (NBIs) will supply 17MW each, by neutralizing accelerated negative hydrogen or deuterium ions. The requirements of ITER NBIs (40A/1MeV D- ions for <=1h, 46A/870keV H- ions for <=1000s) have never been simultaneously attained. So in the Neutral Beam Test Facility (NBTF, Consorzio RFX, Italy) the operation of the full-scale ITER NBI prototype (MITICA) will be tested and optimised up to full performances, focussing on accelerator (including voltage holding), beam optics, neutralisation, residual ion removal. The NBTF includes also the full-scale prototype of the ITER NBI source with 100keV particle energy (SPIDER), for early investigation of: negative ion production and extraction, source uniformity, negative ion current density and beam optics. After three years of experimentation, mainly devoted to verifying the operation of the various plants and to identifying a suitable operational range, SPIDER has recently entered the next operational phase, in which the amount of negative ions available for extraction and acceleration is enhanced by employing the caesium-catalysed conversion at the plasma electrode. This contribution will describe the main results of the first campaign with caesium in SPIDER, devoted to characterizing plasma and beam parameters in these conditions. In preliminary experiments, the expected increase of the negative ion current and simultaneous decrease of the amount of co-extracted electrons were found. The caesiation procedure adopted in SPIDER will be described (effect of: duty cycle, caesium injection rate, RF power, source gas pressure) along with the influence of the control parameters (polarisation of the plasma electrode, magnetic filter field) on the SPIDER beam uniformity. A major shutdown, planned for late 2021, to solve the issues identified during the operation and to carry out scheduled modifications, will be outlined. These improvements, are expected to allow SPIDER to aim at the ITER requirements in terms of negative ion current, electron-to-ion ratio, beam duration.

This document contains the test plan for the SPIDER commissioning campaign S-C1-F addressing the integrated operation of SPIDER Central Safety System with Central Interlock System and CODAS.

This document contains the test report of the SPIDER commissioning campaign S-C1-F addressing the integrated operation of SPIDER Central Safety System, Central Interlock System and CODAS.

This document is the test plan for the MITICA commissioning campaigns M-C1-B addressing the remote control mode of MITICA ISEPS under miniCODAS and the HNB-relevant Plant System Interlock.

This document summarizes the progress of the NBTF Project relevant to the Third Quarter of 2021 including experimental results, issues, and changes (proposed and implemented).

This document summarizes the progress of the NBTF Project relevant to the Second Quarter of 2021 including experimental results, issues, and changes (proposed and implemented).

This document summarizes the progress of the NBTF Project relevant to the First Quarter of 2021 including experimental results, issues, and changes (proposed and implemented).