EMC issues in RF stations for particle accelerators
Stanford Linear Accelerator Center, United States of America
RF systems are used in particle accelerators to add energy to accelerate the beam and to focus the beam in the longitudinal direction. RF stations includes a power stage, based on a tunable resonant cavity, and a feedback system, named Low-Level RF (LLRF), that sets the operating points, regulate the cavity fields, keep the structure on resonance and reject both external disturbances from beam loading and injections of spurious signals to the RF power system. Based on the current and future specifications for the regulation of the accelerating field of the cavities, EMC based design of the LLRF is becoming important to assess the performance requirements. In this paper, an overview of the RF station and the LLRF system is presented, focusing and analyzing the critical areas where an EMC based design is required.
Susceptibility characterization of beam pipe radiated noise for the PXD detector in Belle II experiment
1ITAINNOVA, Instituto Tecnológico de Aragón; 2Max Planck Institute for Physics, Munich, Germany; 3Universidad de Zaragoza, Spain
A new vertex detector used in the upgrade of High Energy Physics experiment Belle II includes DEPFET pixel detector (PXD) technology. Since the PXD is going to be placed 2 mm far from the beam pipe, the effects of radiated interferences may be taken into account. Thought the EM wave associated to the beam is very well confined (skin depth), the beam pipe is grounded to the accelerator and it may have noise currents on its external face due to pumps, auxiliary electronics, power converters, etc., which may produce radiated noise (H field). This analysis is part of the EMC approach that covers the analysis of the emissions and immunity characteristics, as well as the coupling phenomena and grounding issues to define the susceptibility levels required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.
E.M.C. concepts applied to the switching mode power converters supplying the superconductive magnets for the CERN LHC accelerator
1CERN, Switzerland; 2AEMC, France
The LHC (Large Hadron Collider) particle accelerator makes extensive use of switching mode power supplies, in charge of delivering a high precision regulated output current to superconductive magnets controlling and driving the high energy beam of particles. Obtaining such level of precision was achieved through a given approach regarding the architecture of the converter, which was split into three fundamental elements. These three elements had to demonstrate a full compatibility in between them, and regarding the global environment. This paper presents in detail the chosen approach, regarding the EMC (ElectroMagnetic Compatibility) aspect in particular, applied to the power converters.
Electromagnetic pulse in target area at CLPU
1Centro de laseres pulsados, Villamajor, Spain; 2Universitá de Salamanca,Salamanca, Spain; 3Radiofrequency Test Laboratory-Szchenyi Istvn University, Gyor, Hungary; 4ELI-ALPS, Szeged, Hungary
During high intense laser target interaction experiments the big amount of electromagnetic pulses (EMP) can disturb the well performing of all measurements. The effects of the EMP is present not only in the vacuum chamber but also in target area (TA) and it can compromise the use of all detectors and electronic devices.
In this work we characterize the electromagnetic pulse outside the vacuum chamber during high intense laser-target interaction experiments carried out at Centro de Laseres Pulsados (CLPU). The amplitude and the spectrum of the microwave signals in target area are well distinguished from that one’s inside the interaction chamber as the experimental results have shown. Besides this, finite element method (FEM) simulations are used as tools for better interpretation of the results.
EMC versus Safety in Physics Research
Physics research puts considerable hazards into the
hands of researchers. Existing technologies are being pushed
beyond technical limits, new technologies found and explored.
Personnel as well as environment need to be protected. Minimum
waste production becomes an issue too. This paper seeks to
highlight the necessity of adapted EMC procedures and considerations
in order to guarantee a minimum risk of incidents.