Development of Data Acquisition and Control System for Long Pulse Operations of Indian Test Facility of ITER DNB

Abstract

The Indian test facility (INTF) is a negative hydrogen ion-based 100-kV, 60-A, 5-Hz modulated neutral beam injector system having a 3 s on/20 s off duty cycle. The prime objective of the facility is to characterize the ITER diagnostic neutral beam (DNB) with full specifications prior to shipment and installation in ITER. The automated and safe operation of the system will require a reliable and rugged instrumentation and control system that provides control, data acquisition (DAQ), safety, and interlock functions, referred to as INTF-DAQ and control system (DACS). The INTF-DACS has been designed based on the ITER Control, Data Access and Communication (CODAC) architecture and ITER-plant control design handbook guidelines to develop a technical understanding of the CODAC framework to be utilized for the development of plant system instrumentation and control for DNB. The hardware has been selected from the ITER slow-and-fast controller catalog. For high-speed diagnostics, non-National Instruments (NI) high-speed digitizers have been selected. In the area of software, the CODAC core software for control application and NI-LabVIEW for the DAQ application have been finalized. There are around 300 control and 500 acquisition channels consisting of thermal, optical, current, and voltage measurements. The DACS has the mandate to operate INTF for pulselengths up to 3600 s by integrating 14 different plant systems, which includes the power supply plant system under a separate controller. The corresponding development possesses many technical challenges. The estimated file size of a single experimental pulse is in GBs for which the ITER suggested HDF5 format is selected. The timing distribution is another challenge because of the different resolutions required in fast controller, slow controller, and high-speed diagnostics in a distributed area. Long pulse DAQ and monitoring is another challenge. Data exchange across the software platforms, based on Experimental Physics and Industrial Control System (EPICS) and LabVIEW, is also required for integration. At present, the control and DAQ hardware have been integrated and the development phase has been initiated on actual hardware platforms. This paper describes the various developmental activities undertaken to solve the technical challenges in the previously mentioned areas and integration of various components of the DACS toward realizing the full-fledged functional INTF DACS.