Publications de Jean-Philippe Hogge

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Fusion power is the most significant prospects in the long-term future of energy in the sense that it composes a potentially clean, cheap, and unlimited power source that would substitute the widespread traditional nonrenewable energies, reducing the geogr ...

Fusion power may be seen as the energy of the future in the sense that it composes a potentially clean, cheap and unlimited power source that would reduce the worldwide dependency on non-renewable energies. Nevertheless, while nowadays the fusion reaction ...

Gyrotron R&D within the EUROfusion Work Package Heating and Current Drive (WPHCD) is addressing the challenging requirements posed on gyrotrons by the European concept for a demonstration fusion power plant (EU DEMO). These requirements, as specified withi ...

Gyrotrons are essential for electron cyclotron resonance heating (ECRH) in fusion reactors, making their efficient operation crucial for fusion energy. Past experiments revealed instability issues due to trapped electrons in the magnetron injection gun (MIG) region, causing undesired currents and operational failures. To address this, tight manufacturing tolerances are required for the MIG geometry~\cite{pago2}. We present findings of the TRapped Electrons eXperiment (T-REX) at the Swiss Plasma Center, desi

Tokamak à configuration variable (TCV), recently celebrating 30 years of near-continual operation, continues in its missions to advance outstanding key physics and operational scenario issues for ITER and the design of future power plants such as DEMO. The ...

The M1 mirrors are part of the in -vessel quasi -optical Electron Cyclotron beam propagation system of the DEMO nuclear fusion reactor. These four mirrors are all non -movable and with a plane reflecting surface. Based on their functionality they are divid ...

In Europe, the research and development with main focus on achieving robust industrial designs of series gyrotrons for electron cyclotron heating and current drive of today's nuclear fusion experiments and towards a future DEMOnstration fusion power plant ...

In the moderate magnetic field of TCV (1.5 T), the recently installed X3 system (3 gyrotrons, 118 GHz, 0.45 MW each, 2 s) broadens the operational space with the possibility of heating plasmas at high density, well above the cutoff density of the X2 system ...

In the first part of this paper, the status of the 140-GHz continuously operated gyrotrons with an output power of I MW for the stellarator Wendelstein 7-X will be described. With the first series tube, an output power of 1000 kW has been achieved in short ...

The ionization of the residual gas in gyrotrons causes the generation of positively charged ions and negatively charged electrons. Using the electron optics code Ariadne, it was possible to simulate the behavior of these electrons in the overall gyrotron g ...

Gyrotrons are essential devices for the development of nuclear fusion, but their design and reliable operation still present numerous challenges. In particular, certain gyrotrons encounter issues related to trapped electron clouds in the magnetron injectio ...

This paper presents experimental results on the accessibility and the properties of plasmas with improved confinement in TCV. First, the H-mode threshold power is measured in Ohmic plasmas. Above an Ohmic threshold density, the threshold power increases with the density. A lower threshold density is found when additional electron cyclotron heating (ECH) is applied. At these low densities, the threshold power increases dramatically with decreasing density. Only a small fraction of the wide operational domain

On the Tokamak a Configuration Variable (TCV), electron internal transport barriers (eITBs) can be formed during a gradual evolution from a centrally peaked to a hollow current profile while all external actuators are held constant. The formation occurs ra ...

The EU gyrotron for the ITER Electron Cyclotron (EC) heating system has been developed in coordinated efforts of the EGYC Consortium, Thales ED (TED) and Fusion for Energy (F4E) and under the supervision of ITER Organization Central Team. After the success ...

Experiments with high-power electron cyclotron heating (ECH) and current drive (ECCD) in the TCV tokamak are discussed. Power up to 2.7 MW from six gyrotrons is delivered to the tokamak at the second-harmonic frequency (82.7 GHz) in X-mode. The power is transmitted to the plasma by six independent launchers, each equipped with steerable mirrors that allow a wide variety of injection angles in both the poloidal and toroidal directions. Fully non-inductive operation of the tokamak has been achieved in steady

In this paper, we present a detailed analysis of the iterative phase retrieval approach (TPRA) for determining the phase profile of the output microwave beam of a gyrotron from known intensity patterns emphasizing the field propagation techniques which are ...

The physics of tokamak plasmas, in which electrons are heated by electron cyclotron heating (ECH) and whose current is driven by electron cyclotron current drive (ECCD), is investigated in this paper together with applications on tokamak A configuration variable (TCV) using modifications of the pressure and current profiles to improve the operational regimes. In order to explain the experimentally determined current drive efficiency and hard x-ray and electron cyclotron emission measurements, it is shown th

The ECW system on Tokamak a configuration variable (TCV) allows the study of a wide range of poloidal and toroidal launch angles. Both electron cyclotron heating (ECH) and electron cyclotron current drive (ECCD) experiments have been performed to demonstrate the modification of the electron temperature and current profiles. In particular a multi-channel hard X-ray camera (on loan from Cadarache) clearly shows the generation of a high energy electron tail, which increases with increasing toroidal launch angl

In addition to the second harmonic X-mode (X2) electron cyclotron heating (ECH), the TCV ECH system has been completed with three 450 kW gyrotrons operating at the frequency of 118 GHz for third harmonic X-mode (X3) in a top-launch configuration. In the re ...

A model is presented for simulating the electron beam within the entire gyrotron geometry using an electron optics code. The model incorporates the influence of the electromagnetic fields generated by the cavity's operational mode through a simple self-con ...

Jean-Philippe Hogge

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A Variable Structure Control Scheme Proposal for the Tokamak a Configuration Variable

Sliding Surface Based Schemes for the Tokamak a Configuration Variable

Overview of recent gyrotron R&D towards DEMO within EUROfusion Work Package Heating and Current Drive

The Diocotron Instability in the Trapped Electrons Experiment T-REX and its Relevance to Electron Clouds in Gyrotron Guns

Experimental research on the TCV tokamak

Pre-conceptual design of the fixed mirrors for the DEMO Electron Cyclotron Heating antenna

From W7-X Towards ITER and Beyond: 2019 Status on EU Fusion Gyrotron Developments

Third-harmonic, top-launch, ECRH experiments on TCV tokamak

High-power gyrotron development at Forschungszentrum Karlsruhe for fusion applications

Study of Ionized Particles in a Gyrotron Using a Full Gyrotron Simulation Model

Electron trapping in gyrotron electron guns: Validation of the FENNECS code with the T-REX experiment

Accessibility and properties of ELMy H-mode and ITB plasmas in TCV

Safety factor profile requirements for electron ITB formation in TCV

Metrology techniques for the verification of the alignment of the EU gyrotron prototype for ITER

High-power ECH and fully non-inductive operation with ECCD in the TCV tokamak

Theoretical Investigation of Iterative Phase Retrieval Algorithm for Quasi-Optical Millimeter-Wave RF Beams

ECH physics and new operational regimes on TCV

Sustained fully non-inductive scenarios using pressure and current profile control with ECCD

Third harmonic X-mode absorption in a top-launch configuration on the TCV tokamak

Electron optics simulation in the overall gyrotron geometry