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The Plasma Control System Simulation Platform (PCSSP) is a highly flexible, modular, time-dependent simulation environment developed primarily to support development of the ITER Plasma Control System (PCS). It has been under development since 2011 and is scheduled for first release to users in the ITER Organization (IO) and at selected additional sites in 2015. Modules presently implemented in PCSSP enable exploration of axisymmetric evolution and control, basic kinetic control, and tearing mode suppression. A basic capability for generation of control-relevant events is included, enabling study of exception handling in the PCS, continuous controllers, and PCS architecture. While the control design focus of PCSSP applications tends to require only a moderate level of accuracy and complexity in modules, more complex codes can be embedded or connected to access higher accuracy if needed. This paper describes the background and motivation for PCSSP, provides an overview of the capabilities, architecture, and features of PCSSP, and discusses details of the PCSSP vision and its intended goals and application. Completed work, including architectural design, prototype implementation, reference documents, and IO demonstration of PCSSP, is summarized and example use of PCSSP is illustrated. Near-term high-level objectives are summarized and include preparation for release of an “alpha” version of PCSSP and preparation for the next development phase. High-level objectives for future work are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the PFX Operating Early Task (POET) was to obtain a highly shaped plasma and x-point formation in the early phases of the discharge. The PFX is an amplifier which feeds the central pancakes of the JET primary circuit. In the past it was possible to energize the PFX circuit only when the PFGC current, which feeds all the coils of the primary circuit, was already flowing in the same direction as the PFX current would have flowed, to avoid repulsive vertical forces which would tend to lift the top pancakes of the central solenoid, balanced only by the net weight of the upper part of the JET machine. In this paper the modeling activity performed to provide a more accurate estimate of the ejection forces acting on the upper coils in order to safely widen the operational space, by using two dimensional finite element electromagnetic models and the simulation of the performances of the actual controller algorithm on tracking the desired references of current are described. Finally will be presented the results of the implemented POET system, routinely used in JET in the 2011/2012 experimental campaigns, in terms of anticipation of x-point formation and enhanced system flexibility. [Copyright &y& Elsevier]

Abstract: The JET enhancement project Plasma Control Upgrade (PCU) aimed at increasing the capabilities of the plasma vertical stabilization (VS) system. One of the activities of this project was devoted to the development of simple but sufficiently accurate models of the VS system so as to address the main design choices, use the simulation tools as reliable test-beds, and provide an adequate support to the engineering design and commissioning of the new Enhanced Radial Field Amplifier (ERFA). This paper illustrates some of the main achievements of the modelling activity, which gave rise to a closed loop model of the VS system, including plasma, PF coils and passive structures. In particular the paper deals with the selection of the set of turns to be used in the control coils and with the estimation of the eddy current effects on the VS system. The latter analysis addressed an upgrade of the converter units of ERFA, successfully implemented during its commissioning on plasma in August 2009. [Copyright &y& Elsevier]