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Abstract: Validation by means of simulation is a crucial step when developing real-time control systems. Modeling and simulation are an essential tool since the early design phase, when the control algorithms are designed and tested. This phase is commonly carried out in off-line environments such as Matlab® and Simulink®. A MARTe-based simulator has been recently developed to validate the new JET Vertical Stabilization (VS) system. MARTe is the multi-thread framework used at JET to deploy hard real-time control systems. This paper presents the software architecture of the MARTe-based simulator and it shows how this tool has been effectively used to evaluate the effects of Edge Localized Modes (ELMs) on the VS system. By using the simulator it is possible to analyze different plasma configurations, extrapolating the limit of the new vertical amplifier in terms of the energy of the largest rejectable ELM. [Copyright &y& Elsevier]

Tokamaks are the most promising approach for nuclear fusion on earth. They are toroidal machines where the plasma is heated in a ring-shaped vessel and kept away from the vessel by applied magnetic fields. To achieve high performance in tokamaks, plasmas with elongated poloidal cross-section are needed. Such elongated plasmas are vertically unstable, hence position control on a fast time scale is clearly an essential feature for all tokamak devices. In this context the Plasma Control Upgrade project was aimed at increasing the capabilities of the Vertical Stabilization (VS) of the JET tokamak. This paper introduces the new JET VS system and focuses on how the flexibility of this real-time system has been exploited to enlarge its operational limits in terms of maximum controllable disturbance. Eventually, some experimental results achieved during the last experimental campaigns are presented. [ABSTRACT FROM PUBLISHER]

The achievement of the required performances during the operation of large fusion experimental reactors, is strictly related to the flexibility and reliability of the real-time infrastructures. It turns out that, in tokamak reactors, the real-time infrastructure has to be designed so as to meet a number of common requirements. An overview of the real-time infrastructure currently adopted at the JET tokamak is given in this paper, focusing the attention on the solutions that have been developed for addressing these common requirements. Furthermore, three real-time systems recently deployed at JET are described as example. [ABSTRACT FROM PUBLISHER]

The impact of the 3D effects on the dynamic response of the plasma in the JET tokamak is assessed on the time scale of interest for plasma magnetic control and stabilization. These effects are due to the limbs of the magnetic circuit and to the eddy currents in the 3D metallic structures. The plasma behaviour is taken into account by a specific matrix of modified inductances interacting with the remaining part of the system via a virtual coupling surface. [ABSTRACT FROM AUTHOR]

Abstract: A project dedicated to the enhancement of the JET vertical stabilization system was launched in 2006, including an upgrade of the Power Supply of the Radial Field Amplifier, of hardware and software of the vertical stabilization control system. The main aim was to double the JET capability in stabilising high current plasmas when subject to perturbations, in particular large Edge Localised Modes. We present here the results of first plasma operation with the new Enhanced Radial Field Amplifier and its data acquisition and control system, focussing on the benefits of an approach based on phased commissioning, modelling and offline algorithm validation. [Copyright &y& Elsevier]