M. Eguiraun

ESS-Bilbao light-ion linear accelerator and neutron source: design and applications

The baseline design for the ESS-Bilbao light-ion linear accelerator and neutron source has been completed and the normal conducting section of the linac is at present under construction. The machine has been designed to be compliant with ESS specifications following the international guidelines of such project as described in Ref. [1]. The new accelerator facility in Bilbao will serve as a base for support of activities on accelerator physics carried out in Spain and southern Europe in the frame of different ongoing international collaborations. Also, a number of applications have been envisaged in the new Bilbao facility for the outgoing light ion beams as well as from fast neutrons produced by low-energy neutron-capture targets, which are briefly described.

ISHN Ion Source Control System. First Steps Toward an EPICS Based ESS-Bilbao Accelerator Control System

ISHN (Ion Source Hydrogen Negative) consists of a Penning type ion source in operation at ESS-Bilbao facilities. From the control point of view, this source is representative of the first steps and decisions taken towards the general control architecture of the whole accelerator to be built. The ISHN main control system is based on a PXI architecture, under a real-time controller which is programmed using LabVIEW. This system, with additional elements, is connected to the general control system. The whole system is based on EPICS for the control network, and the modularization of the communication layers of the accelerator plays an important role in the proposed control architecture.

Experimental implementation of a networked input-output sporadic control system

Event-based control (EBC) is growing in importance since this paradigm leads to a better integration with networked systems. Particularly due to the distributed and asynchronous inherent nature of such systems. The reported main advantage is the reduction of the control rate allowing a less saturated communication network. This fact has been proved with different EBC schemes, as using impulse control schemes within stochastic environments and different PID structures. In this work, the experimental study of an event based input-output control scheme is presented, following the sporadic control approach and implemented in a networked environment. In this scenario, noise minimizes the advantages of event-based schemes. The use of a filtering strategy minimizes its effect, restoring the reduction of the control rate. This kind of approach leads to interesting practical applications. Simulation and experimental results show the performance of the control approach under study.

Design and Performance Analysis of a Nonstandard EPICS Fast Controller

Large scientific projects present new technological challenges, such as the distributed control over a communication network. In particular, the middleware Experimental Physics and Industrial Control System (EPICS) is the most extended communication standard in particle accelerators. The integration of modern control architectures in these EPICS networks is becoming common, as for example for the PXI/PXIe and xTCA hardware alternatives. In this paper, a different integration procedure for PXI/PXIe real-time controllers from National Instruments is proposed, using LabVIEW as the design tool. This methodology is considered and its performance is analyzed by means of a set of laboratory experiments. This control architecture is proposed for achieving the implementation requirements of fast controllers, which need an important amount of computational power and signal processing capability, with a tight real-time demand. The present paper studies the advantages and drawbacks of this methodology and presents its comprehensive evaluation by means of a laboratory test bench, designed for the application of systematic tests. These tests compare the proposed fast controller performance with a similar system implemented using an standard EPICS IOC provided by the CODAC system.

Stability analysis and control design of a class of event based control systems

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.

Adjustable ECR ion source control system: Ion Source Hydrogen Positive project

ISHP (Ion Source Hydrogen Positive) project consists of a highly versatile ECR type ion source. It has been built for several purposes, on the one hand, to serve as a workbench to test accelerator related technologies and validate in-house made developments, at the first stages. On the other hand, to design an ion source valid as the first step in an actual LINAC. Since this paper is focused on the control system of ISHP, besides the ion source, all the hardware and its control architecture is presented. Nowadays the ion source is able to generate a pulse of positive ions of Hydrogen from 2 μs to a few ms range with a repetition rate ranging from 1 Hz to 50 Hz with a maximum of 45 mA of current. Furthermore, the first experiments with White Rabbit (WR) synchronization system are presented.

Event-based temperature control system in a penning-type ion source

The ion sources are the first step in particle accelerators, which are important instruments in todays scientific advance, with multiple applications. The design and construction of those machines involves complex technical challenges. One of the keys in the correct operation of an Ion Source is the control system. In this work, an event-based control of the temperature in the transport line and cesium boilers is presented, necessary elements in a Penning-type ion source. The main objective of the controller is to maintain a constant temperature in the transport line and the boiler, providing an adequate concentration of cesium in the plasma chamber. The event-based nature of the controller reduces the control rate and, hence, the activity of the actuators. Therefore, the lifetime of the devices is increased, improving system reliability.

A Java based tool for distributed control systems

In this work in progress practice the use of Java programming language, and a Java library called ProActive, for developing distributed control systems is presented. The authors are developing a middleware which provide services for communicating several tools presented in scientific and industrial facilities like EPICS and Labview. The first efforts are focused on the communication scheme between those elements, granting reconfigurable nature to the system.

Performance analysis of a non-standard EPICS fast controller

The recent large scientific projects present new technological challenges, such as the distributed control over a communication network. In particular, the middleware EPICS is the most extended communication standard in particle accelerators. The integration of modern control architectures in these EPICS networks is becoming common, as for example for the PXI/PXIe and xTCA hardware alternatives. In this work, a different integration procedure for PXIe real time controllers from National Instruments is proposed, using LabVIEW as the design tool. This control architecture is proposed for achieving the implementation requirements of fast controllers, which need an important amount of computational power and signal processing capability, with a tight real-time demand. The present work studies the advantages and drawbacks of this methodology and presents its comprehensive evaluation by means of a laboratory test bench, designed for the application of systematic tests. These tests compare the proposed fast controller performance with a similar system implemented using an standard EPICS IOC provided by the CODAC system.