Development of Real-Time Controller-Based Data Acquisition System for 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 NBI system having 3-s ON/20-s OFF duty cycle. Prime objective of the facility is to characterize 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 which provide control, data acquisition (DAQ), safety, and interlock functions, referred as INTF-DACS. The INTF-DACS has been designed based on the ITER CODAC architecture and ITER- plant control design handbook (PCDH) guidelines with the aim of developing the technical understanding of CODAC framework to be utilized for development of plant system instrumentation and control for DNB. Presently, the development work has been initiated for both the control system and DAQ system of INTF DACS. The INTF DAQ system has to perform functions related to acquiring, monitoring, timing synchronization, and archiving of the signals. It also has to interface with the control system of INTF to ensure proper operations. The DAQ system is designed for acquiring over 700 signals for 14 plant systems. The development of this whole system is done in NI LabVIEW using NI real-time PXIe. The PXIe platform with RTOS performs acquisition of signals at sampling rate of up to 10 KS/s. One of the main challenges is to develop the DAQ system to support multichannel triggered-based acquisition and monitoring for pulse durations up to 3600 s. The host layer is a distributed processing system consisting of two hosts and database system. To ensure timing synchronization, a dedicated timing network is included based on IEEE 1588 protocol with help of PXI timing cards. This helps in providing a timing reference to other future systems. For archiving data, MySQL-based data server is integrated for storing data for each experimental shot continuously which can be utilized later for query based data retrieval. In this paper, the development strategy and test results are discussed in order to develop the DAQ system for INTF including the development of interfaces with other components of DACS and experiences obtained, which can be utilized to develop similar DAQ systems of large scale. The novel methods developed for monitoring signals and file size reduction are also discussed.