Preliminary Design of NCSX Central Computing and Control

The National Compact Stellarator Experiment (NCSX) is the centerpiece of the U.S. effort to develop the physics understanding of the compact stellarator and evaluate its potential for future fusion energy systems. A core component of the NCSX project is central computing and control, which is comprised of seven elements: 1) Networking and fiber optic infrastructure, 2) Central instrumentation and controls, 3) Diagnostic data acquisition and facility computing, 4) Facility timing and synchronization, 5) Realtime plasma and power supply control, 6) central safety and interlock system, and 7) Control room facility. NCSX central computing will build upon the success of the central computing model of the National Spherical Torus Experiment (NSTX). Like NSTX, a key design principle for the NCSX computing system is to use commodity computing hardware, and open-source and collaborative software wherever practical. Three major software codes of this type will be used: EPICS, MDSplus, and the integrated plasma control software from General Atomics. This paper will present an overview of the primary elements of the Central Computing and Controls, illustrate the use of open-source and collaborative software, and describe the new technologies that will advance the computing and control capabilities for NCSX.