The 100 Tm superconducting synchrotron SIS100 is the main accelerator of the international Facility for Antiproton and Ion Research (FAIR) currently under advanced construction in Darmstadt, Germany. ...The SIS100 dipole circuit which creates the magnetic field required to bend the beam, consists of 108 dipoles distributed over six arc sections of the ring. The magnetic field for the beam focusing is generated by three individual quadrupole circuits with total amount of 166 magnets located in both arc and straight sections of the ring. The dipole circuit is powered from two synchronized power converters and will be cycled up to 13.2 kA at 28 kA/s. The dipole magnet chain is not self-protecting. 12 energy extraction resistors are used to protect the superconducting coils and bus-bars against overheating and overvoltage in case of a quench. The largest quadrupole circuit consists of 83 magnets. The nominal current is 10.5 kA cycled up to 22 kA/s. Similarly to dipoles, the quadrupole circuit is not self-protecting. Four energy extraction units are used to discharge the circuit's energy in case of a quench or fast power abort. This work presents a customized Python software tool created to simulate electrical behavior of a superconducting magnet chain. The software is under development at GSI. However, certain modules strongly rely on the approach developed at CERN. The paper contains selected simulations of the SIS100 dipole and defocusing quadrupole circuits. Special attention is drawn to: transient effects during typical operation and during the fast power abort; the damping effect of vacuum chambers; voltage distribution in the circuits and basic failure modes.
•FDM implicit scheme (unconditionally stable) used for thermal calculation.•Quench in SC coils with strong thermal anisotropy can be modelled in 1D.•Voltage nodal analysis enables calculation of ...inter-turn voltages.
The FAIR Project – a new international Facility for Antiproton and Ion Research is under construction in Darmstadt, Germany. The core machine at FAIR is the SIS100 synchrotron which utilises superconducting magnets in order to guide the heavy ion beam. The bending component of the magnetic field is generated by super-ferric window-frame dipole magnets symmetrically distributed over the six arc sections of the accelerator ring. The dipole coils are wound with a LTS low AC loss Nuclotron-type cable. Due to the very thick inter-turn insulation, the coil is characterized by a strong anisotropy of thermal conductivity which enables application of a 1D electro-thermal model. This work presents the latest version of the magnet model used for the simulation of magnet’s operating modes at the test facility (including quench). Since currently the series dipole magnets undergo acceptance tests at cryogenic conditions, the simulation results are compared to the available measurements.
The heavy ion synchrotron SIS100, the core machine of the new international Facility for Antiproton and Ion Research (FAIR) in Darmstadt, is currently under construction. The 108 superconducting ...dipole magnets of SIS100 will be powered in series with a cycling rate up to 30kAs−1 which corresponds to 4Ts−1. The dipole magnet protection system considers 12 energy extraction resistors and two crowbars at the outputs of two power converters. As a part of the Failure Mode and Effects Analysis, the most critical failures of the magnet protection system are simulated. In this contribution, initial studies of the electrical and thermal behaviour of the SIS100 main dipole circuit during a quench are presented. The dipole magnet design and topology of the powering circuit (including the protection system) are described. The electro-thermal model in use is detailed. Finally, simulation of a failure mode of the magnet protection system is presented and results are discussed.
The Super-FRS (superconducting fragment separator) will be constructed in the frame of the Facility for Antiproton and Ion Research project at GSI (Darmstadt, Germany). This work presents quench ...calculations done on the Super-FRS main dipole magnet. Two quench programs were used. One developed at CIEMAT (Madrid, Spain), and the other developed at GSI. Both quench programs use finite-difference method. For the GSI quench program the mesh size influence was investigated. A protection system for Super-FRS dipoles is presented as well. Optimum energy extraction resistors for the Super-FRS dipoles were calculated. Quench calculations are compared to measurements done on the first dipole prototype.
The scientific goal of the CBM (Compressed Baryonic Matter) experiment at FAIR (Darmstadt) is to explore the phase diagram of strongly interacting matter at highest baryon densities. The physics ...program of the CBM experiment is complimentary to the programs to be realized at MPD and BMN facilities at NICA and will start with beam derived by the SIS100 synchrotron. The 5.15 MJ superconducting dipole magnet will be used in the silicon tracking system of the CBM detector. The magnet will provide a magnetic field integral of 1 Tm which is required to obtain a momentum resolution of 1% for the track reconstruction. The results of the development of dipole magnet of the CBM experiment are presented.
The scientific mission of the Compressed Baryonic Matter (CBM) experiment is the study of the nuclear matter properties at the high baryon densities in heavy ion collisions at the Facility of ...Antiproton and Ion Research (FAIR) in Darmstadt. The 5.15 MJ superconducting dipole magnet will be used in the silicon tracking system of the CBM detector. It will provide a magnetic field integral of 1 Tm which is required to obtain a momentum resolution of 1% for the track reconstruction. This paper presents quench modeling and evaluation of candidate protection schemes for the CBM dipole magnet. Two quench programs based on finite-difference method were used in simulation. One of them is currently used at GSI, and the other based on CIEMAT (Madrid, Spain) was modified to perform quench calculation for the CBM magnet.
The SIS100 synchrotron is the core accelerator of the FAIR project (Darmstadt, Germany). The long term operation of such an advanced superconducting machine requires adequate Electrical Integrity. ...Issues related to EI shall be taken into account at the design, production and commissioning stage respectively. In order to assure the safe and reliable operation of the superconducting magnets at cryogenic conditions, the facility shall be equipped with active protection systems. When using superconducting technology, quench detection and magnet protection are the most essential systems. Their design has a strong influence on the coordination of electrical insulation systems. This paper focuses on the correlation between EI and active protection systems. The presented study provides the basis for the development of adequate electrical integrity tests (including acceptance criteria) that should be performed at both the production and test stage. In this work, the case of SIS100 synchrotron is considered as an example.
The Heavy Ion Synchrotron SIS100 is the core facility of the international FAIR project at GSI in Darmstadt. The magnet system of the synchrotron will operate with a high cycle frequency up to 1Hz. ...The magnet coils are made of a hollow NbTi composite cable cooled by forced flow of two phase helium. The dynamic heat losses in the magnets caused by fast ramping provide the major part of the heat load to the cryogenic system of SIS100. Recently the first series dipole magnet was produced and is being intensively tested at the cryogenic magnet test facility at GSI. We present the status of these tests together with the obtained opera- tion characteristics like a cool down and training behaviour, dynamic heat release and mass flow rates.
The FAIR project 1 undertaken at GSI (Darmstadt, Germany) will lead to the construction of 2 superconducting synchrotrons and one superconducting fragment separator called Super-FRS. This paper ...presents quench measurements and calculations on the FAIR Super-FRS dipole using two different 3D FEM programs. The first (called Opera Quench) gives the same order of propagation velocities as those computed with a 1D program. The second (developed by CIEMAT) succeeds to reproduce the current drop and quench resistance measured on the Super-FRS dipole.
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