Recent results from R&D on superconductors at CRPP

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Utilizing the TokaMaker code, this manuscript presents a scheme for determining the optimal locations of poloidal field coils in tokamak configurations, aimed at reducing the currents required to reproduce target equilibrium in future devices. The definition of the coil position space is described, as well as the cost function is to be minimized, which incorporates the constraints of the problem. The MANTA reactor design, featuring strong negative triangularity shaping, is considered as a test example, wher

JET, the only tokamak capable of operating with deuterium-–tritium (D-T) fuel (since TFTR was shutdown in 1999), has provided essential experimental data to support ITER and DEMO design and operation. Within the EUROfusion Tokamak Exploitation Work Package, JET completed its final campaigns (2022--2023), culminating in the third D-T campaign (DTE3). These experiments addressed key challenges in plasma scenarios, exhaust control, and tritium management under reactor-relevant conditions. Significant progress

Research on the Tokamak à Configuration Variable (TCV) addresses a wide range of key questions relevant to ITER and future fusion power plants. Over the past two years, highly productive experimental campaigns have led to major advances across several areas: the ITER baseline scenario; pedestal properties in low-collisionality, peeling-limited conditions; and the development of high-

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, non-inductive regimes. Alternative high-confinement scenarios have likewise received significant attention, with re

Geothermal energy is heat energy generated and stored in the Earth. With the awareness of the society about environmental issues, geothermal power is developing worldwide. It is cost-effective, reliable, sustainable, and environmentally friendly but has historically been extracted from the depth of the earth. Recent technological advances permits to use this energy from the shallow depth of the earth. Thanks to infrastructure foundations combined with heat pump technology, we are able to use this geothermal

Industrial waste heat is abundant and represents significant energy inefficiency for many processes. With increasing emphasis on improving industrial energy efficiency, heat pump systems (including refrigeration) offer a solution by valorizing low-temperature waste heat. Optimization of industrial heat pump systems attempts to reach the cost-optimal configuration of equipment (compressors, evaporators, etc.), the sizes, operating conditions (pressures levels, temperatures), and working fluids which can be e

MHD stability is studied in the frame of ITER like hybrid scenarios, characterized by weak reversed shear, with particular attention on ideal internal kink modes and infernal mode stability. Numerical simulations for ITER like equilibria, with hollow q profiles with an off axis minimum close to unity, were carried out using the 3-D equilibrium code ANIMEC, which showed the presence of a 3-D helical core [1] with the characteristics of a saturated internal kink mode. The internal kink perturbation has been i

The stability of Alfv´en eigenmodes (AEs) is studied experimentally in the JET tokamak, by observing the plasma response to antenna-driven frequency-sweeping perturbations at the plasma edge. During the 2008/9 experimental campaigns, the complete set of the new AE antennas was operated and damping measurements for intermediate toroidal mode numbers (n) were collected under various plasma conditions. The quantity and the quality of the measurements reflect a significant effort put in the technical aspects of

The ac loss of superconducting composite depends strongly on coupling between superconducting filaments via the resistive matrix. The established technique for loss reduction using twisted filaments relies on the decoupling of the filaments below a critical coupling field Bc, which increases with the reduction of the twist pitch and the matrix conductivity. Although the concept of Bc may be clearly demonstrated using two infinite slabs of finite length, further details on its correlation with the filament/c

The experiments of Cable-in conduit conductor (CICC) short samples with high proportion of segregated copper strands have been carried out in SULTAN facility last September. These experiments aimed to investigate transient stability and AC losses of CICC conductor coated with different resistive barriers (Pb-30Sn-2Sb or Ni plating on strands) and to check the design of PF and TF CICC for HT-7U magnets. The resistive barriers' influences on the stability and AC losses of CICC are evaluated. These experimenta

The index n of the voltage-current characteristic of large superconductors is a crucial parameter to assess the allowed range for coil operation. In the tests of the Insert coils at the CSMC as well as in the short sample test in the SULTAN facility, it is observed that the index n dramatically decreases from the Nb3Sn strands extracted from cable-in-conduit provide the evidence of a permanent performance drop in the strands, likely due to the transverse load accumulation at the strand crossovers in the cab

The Forschungszentrum Karlsruhe (FZK) and the Centre de Recherches en Physique des Plasmas (CRPP) are working on a joint development program to construct and test a 70 kA current lead using High Temperature Superconductors (HTS) for the Toroidal Field (TF) coil system of the International Thermonuclear Experimental Reactor, ITER-FEAT. This program follows the development program of an HTS current lead in the 20 kA range which was successfully completed in 2000. The HTS part of the current lead will be manuf

Due to the opening or closing operation of circuit breakers and disconnected switches in gas-insulated substations (GIS), a very strong transient wave process can be generated along the three-phase transmission system and transient electromagnetic field can be radiated from the junction between the GIS enclosure and the high-voltage cables. Based on a kind of hybrid method, the software TEMFGIS is provided to predict the radiated field in time domain. Its validity is verified by the measurement results

Voltage sags are one of major concerns in power quality, as they cause serious malfunction of a large number of apparatuses. There are a number of reasons for voltage sags in distribution networks: there is some evidence, however, that in electrical systems located in regions with high value of isokeraunic level, lightning can cause the majority of voltage sags. Data from lightning location systems, which provide an estimation of both lightning flash location and return-stroke current amplitude, can then be

SULTAN, the world wide unique, high field, large bore test facility. has been built as European contribution to the development program for ITER, The facility has primarily been devoted to the qualification of full-size cable-in-conduit-conductors (CICC) foreseen as potential candidates for use in the Central-Solenoid (CS) and the Toroidal-Field (TF) coils of ITER, Fields up to 11 T can be imposed to the vertically inserted CICC-Samples. Horizontal insertion of coiled long conductor samples is possible as d

Magnetohydrodynamic (MHD) instabilities can limit the performance and degrade the confinement of tokamak plasmas. The Tokamak à Configuration Variable (TCV), unique for its capability to produce a variety of poloidal plasma shapes, has been used to analyse various instabilities and compare their behaviour with theoretical predictions. These instabilities are perturbations of the magnetic field which usually extend to the plasma edge where they can be detected with magnetic pick-up coils as magnetic fluctuat

This paper introduces a novel of mini-hybrid solar power plant integrating a field of solar concentrators, two superposed Organic Rankine Cycles (ORC) and a (bio)Diesel engine. Turbines for the organic Rankine Cycles are hermetic scroll expander-generators. Sun tracking solar collectors are composed of rows of flat mirror bands (CEP) arranged in a plane, which focus the solar energy onto a collector tube similar to those used in SEGS plant in California. The waste heat from both the exhaust gases and block

A large variety of shaped tokamak discharges have been created in the Tokamak a Configuration Variable (TCV) with main parameters B-T

Numerous degrees of freedom are often available for the heat integration of batch processes. Usually, only few of these are actually considered and optimized. Time slice-dependant Tmin have been investigated and optimized using a supertargeting procedure originally developed for multiple base case design. The trade-off direct indirect heat exchanges has also been studied and tools for the preliminary assessment of the heat storage system are proposed. Further improvements are being considered for both t

NOVELTY - For control mono-phase or multiphase machines in motor or generating mode with or without pulse width modulation. USE - Control of electrical rotating machines. ADVANTAGE - Can be used for control of single phase and three phase machines. DETAILED DESCRIPTION - The method for control of a permanent magnet synchronous motor (10) from a supply source (11) without direct sensing, having at least a phase, a winding, and a rotor. The supply to each phase of the motor is controlled. The output signals f

We have studied the influence of Co and Ni doping on the electronic band structure and the transport properties of high-temperature superconductors. The doping has dramatic effects on both the normal and the superconducting state. Upon doping the residual resistivity increases strongly. For sufficiently high Co concentration the temperature dependence rho(T) turns from a simple linear dependence to one displaying a minimum around T-min = 190 K. This minimum is followed by an upturn (d rho/dT

Recent results from R&D on superconductors at CRPP

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Poloidal field coils optimization for the MANTA tokamak using TokaMaker

Results from the last DD and DT JET campaigns in the framework of the EUROfusion Tokamak Exploitation Work Package Activity

Progress and innovations in the TCV tokamak research programme

Numerical simulation of deck de-icing using energy pile systems

General Superstructure Synthesis and Bi-level Solution Strategy for Industrial Heat Pumping

MHD properties in the core of ITER-like hybrid scenarios

Optimization of the active MHD spectroscopy system on JET for the excitation of individual intermediate and high-n Alfvén eigenmodes

3D Modeling of Coupling Between Superconducting Filaments via Resistive Matrix in AC Magnetic Field

Test results and analyses of conductor short samples for HT-7U

The voltage/current characteristic (n index) of the cable-in-conduit conductors for fusion

Development of high temperature superconductor current leads for 70 kA

Prediction of switching transient electromagnetic fields in gas-insulated substations

Use of lightning location systems data in integrated systems for power quality monitoring

Facility status and results on ITER full-size conductor tests in SULTAN

MHD stability limits in the TCV tokamak

Small Hybrid Solar Power System

"Profile consistency" features in strongly shaped Ohmic tokamak plasmas

Improving Pinch Analysis based heat integration of single & multi-product batch plants

Method and device for controlling a synchronous motor with permanent magnet (Procédé et dispositif de commande d'un moteur synchrone à aimant permanent)

Localization effects in Co- and Ni-doped Bi2Sr2CaCu2O8+gamma