Fusion Engineering and Design 84 (2009) 1049–1054 Contents lists available at ScienceDirect Fusion Engineering and Design journal homepage: www.elsevier.com/locate/fusengdes Development and commissioning results of the KSTAR discharge control system Kukhee Kim a,* , Mikyung Park a , Sang-Hee Hahn a , Myungkyu Kim a , Jaesic Hong a , Sulhee Baek a , Taegu Lee a , Sang-Il Lee a , Jin-Seop Park a , Jaehoon Choi a , Jayhyun Kim a , Hyun Sik Ahn b , Kap-Rae Park a , Yeong-Kook Oh a a National Fusion Research Institute, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea b POSCON Corporation R&D Center, 101 Korea Techno Complex Building, Korea University, Seoul 136-713, Republic of Korea article info Article history: Available online 20 December 2008 Keywords: KSTAR Superconducting Tokamak Discharge control EPICS vxWorks Linux abstract The Korea Superconducting Tokamak Advanced Research (KSTAR) control system has been developed as a network-based distributed control system composed of several sub-systems. There are many local control systems for various sub-systems, and the central control system includes discharge control, machine control, and safety interlocks which aim for integrated control of the entire system. We have chosen the Experimental Physics and Industrial Control System (EPICS) as the middleware of the KSTAR control system because EPICS provides a software framework to integrate heterogeneous systems. The discharge control system, which is implemented in a part of the supervisory control system, performs the discharge sequence execution. The plasma control system, which has been implemented with general atomics and modified for KSTAR, is involved in the discharge control. The plasma control system performs real- time plasma control algorithms and provides the results of the control algorithms to the magnet power supplies. We are using a reflective memory-based real-time network for communication between the plasma control system and the magnet power supplies, thus we developed a fully digital control for the magnet power supplies. We have implemented the discharge control system with state notation language (SNL) in EPICS and also developed interface software among the sub-systems. We will present the details of the development of the KSTAR discharge control system and commissioning results. © 2008 Elsevier B.V. All rights reserved. 1. Introduction The Korea Super Conducting Tokamak Advanced Research (KSTAR) [1] is a superconducting Tokamak, which is composed of diverse sub-systems. The sub-system named the local control sys- tem contains more than 200 controllers and workstations which are distributed in the KSTAR main building and accessory build- ings. The integrated control system for KSTAR [2] was developed as a network-based distributed control system using the Experimen- tal Physics and Industrial Control System (EPICS) [3]. The KSTAR integrated control system performs the control and monitoring of more than 13,200 processing variables in the operation and com- municates about 55,200 events per second between the internal systems. The supervisory control system synthesizes the administration of the local control systems. It controls and monitors the local control systems to maintain and preserve the operational state of KSTAR and manages the computing resources to archive the oper- ation data and to display the data. The supervisory control system * Corresponding author. Tel.: +82 42 870 1616; fax: +82 42 870 1609. E-mail address: kimkh@nfri.re.kr (K. Kim). can be categorized into three functions: machine control, discharge control, and data management and visualization. Fig. 1 shows the structure of the KSTAR integrated control system and the function block of the supervisory control system. The machine control monitors the operation status of the entire system for 24 h a day and maintains and preserves the operation. KSTAR has six operation stages: maintenance, vacuum pumping, cool-down, current charge-up, plasma experiments, and warm- up. The machine control establishes the operation stage, sets the alarm and interlock configurations to match the operation stage, and intervenes during the entire period of the KSTAR operation. The discharge control is activated during the plasma experiment stage in contrast with the machine control. It performs the pre-processing of the shot, the plasma discharge, and the post-processing. The machine control and the discharge control are implemented in the central control system (CCS) which is a part of the KSTAR supervi- sory control system. 2. Discharge control system In the pre-processing step, the discharge control performs the preparation of the plasma discharge shot: the operator sets the timing configuration on the time synchronization system 0920-3796/$ – see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2008.11.005