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Zamudio, Spain

Sanz D.,Technical University of Madrid | Ruiz M.,Technical University of Madrid | Eguiraun M.,University of the Basque Country | Arredondo I.,ESS Bilbao Consortium | And 4 more authors.
Fusion Engineering and Design | Year: 2015

Experimental Physics and Industrial Control System (EPICS) is a software tool that during last years has become relevant as a main framework to deploy distributed control systems in large scientific environments. At the moment, ESS Bilbao uses this middleware to perform the control of their Ion Source Hydrogen Positive (ISHP) project. The implementation of the control system was based on: PXI Real Time controllers using the LabVIEW-RT and LabVIEW-EPICS tools; and RIO devices based on Field-Programmable Gate Array (FPGA) technology. Intended to provide a full compliant EPICS IOCs for RIO devices and to avoid additional efforts on the system maintainability, a migration of the current system to a derivative Red Hat Linux (CentOS) environment has been conducted. This paper presents a real application case study for using the NIRIO EPICS device support (NIRIO-EDS) to give support to the ISHP. Although RIO FPGA configurations are particular solutions for ISHP performance, the NIRIO-EDS has permitted the control and monitoring of devices by applying a well-defined design methodology into the previous FPGA configuration for RIO/FlexRIO devices. This methodology has permitted a fast and easy deployment for the new robust, scalable and maintainable software to support RIO devices into the ISHP control architecture. © 2015 Elsevier B.V. All rights reserved.

Cortazar O.D.,University of Castilla - La Mancha | Megia-Macias A.,ESS Bilbao Consortium
IEEE Transactions on Plasma Science | Year: 2016

A novel strongly eccentric rotating plasma lamina structure subtending approximately an angle of 120° is reported in a 2.45-GHz driven electron cyclotron resonance hydrogen discharge in the proximity of the chamber wall. Shape and rotation frequencies depend critically on the embedded magnetic field distribution in the plasma chamber as well as on neutral gas pressure and microwave power. The discharge denominated test-bench for ion-sources plasma studies includes a transparent doubled shielded quartz window that keeps the microwave resonance condition. An ultrafast microchannel plate charge-coupled device frame camera is used to obtain four pictures of 1-μs exposure time each during a single plasma pulse in the visible emission range. E × B drift is pointed as that responsible for driving the rotational behavior of a thick plasma sheath, where the scale of the quasi-neutrality breaking is estimated ten times greater than that in a typical plasma sheath. © 2016 IEEE.

Jauberteau J.L.,French National Center for Scientific Research | Jauberteau I.,French National Center for Scientific Research | Cortazar O.D.,University of Castilla - La Mancha | Megia-Macias A.,ESS Bilbao Consortium
Physics of Plasmas | Year: 2016

Time evolution of the Electron Energy Distribution Function (EEDF) is measured in pulsed hydrogen microwave magnetoplasma working at 2.45 GHz. Analysis is performed both in resonance (B = 0.087 T) and off-resonance conditions (B = 0.120 T), at two pressures (0.38 Pa and 0.62 Pa), respectively, and for different incident microwave powers. The important effect of the magnetic field on the electron kinetic is discussed, and a critical analysis of Langmuir probe measurements is given. The Electron Energy Distribution Function is calculated using the Druyvesteyn theory (EEDF) and is corrected using the theory developed by Arslanbekov in the case of magnetized plasma. Three different components are observed in the EEDF, whatever the theory used. They are: (a) a low electron energy component at energy lower than 10 eV, which is ascribed to the electron having inelastic collisions with heavy species (H2, H, ions), (b) a high energy component with a mean energy ranging from 10 to 20 eV, which is generally ascribed to the heating of the plasma by the incident microwave power, and (c) a third component observed between the two other ones, mainly at low pressure and in resonance conditions, has been correlated to the electron rotation in the magnetic field. © 2016 AIP Publishing LLC.

Cortazar O.D.,University of Castilla - La Mancha | Megia-Macias A.,ESS Bilbao Consortium | Megia-Macias A.,CERN | Tarvainen O.,University of Jyvaskyla | And 2 more authors.
Review of Scientific Instruments | Year: 2016

An experimental study of plasma distributions in a 2.45 GHz hydrogen discharge operated at 100 Hz repetition rate is presented. Ultrafast photography, time integrated visible light emission spectra, time resolved Balmer-alpha emission, time resolved Fulcher Band emission, ion species mass spectra, and time resolved ion species fraction measurements have been implemented as diagnostic tools in a broad range of plasma conditions. Results of plasma distributions and optical emissions correlated with H+, H2 +, and H3 + ion currents by using a Wien filter system with optical observation capability are reported. The magnetic field distribution and strength is found as the most critical factor for transitions between different plasma patterns and ion populations. © 2015 AIP Publishing LLC.

Jugo J.,University of the Basque Country | Eguiraun M.,ESS Bilbao Consortium
Proceedings of the 2012 UKACC International Conference on Control, CONTROL 2012 | Year: 2012

Event Based Control (EBC) provides a reduction of mean control rates, which is an important advantage in control systems, specially when network environment gets involved. For this reason, the study of design methodologies for EBC systems that met desired specifications regarding stability and performance issues are a valuable research field. This work presents a control design process applied to a class of EBC systems using LMIs, including stability issues on the light of Asynchronous Dynamical System theory. The application of the proposed methodology is presented by an example, showing good performance in simulation results. © 2012 IEEE.

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