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This paper describes the characterisation of an optical tracking system that allows to accurately locate the position of a magnetic sensor used for measuring the magnetic field generated from inductive charging of electrical vehicles. This paper forms part of the metrology for inductive charging of electric vehicles (MICEV) project. 2D measurements have been successfully carried out with the optical tracking system and the data acquisition has been automated by means of a dedicated software routine. The experimental setup, results, data and uncertainty analysis are presented in this paper. We show that the expanded uncertainty of the tracking system is ±0.64 mm with a coverage factor $k$ = 2, providing a coverage probability of approximately 95%.

A thermionic cusp electron gun has been designed, numerically optimized and experimentally measured and is presented. A 40 kV, 1.5 A annular axis-encircling electron beam has been simulated to generate a beam with low velocity and alpha spreads. The electron gun performance has been verified through experiments and the results are given.

Summary form only given. The European Gyrotron Consortium (EGYC) is responsible for developing one set of 170 GHz mm-wave sources, in support of Europe's contribution to ITER1. The original plan of targeting a 2 MW coaxial gyrotron is currently under discussion, in view of essential delays and damages. This paper reports on the latest results and plans with regard to the 2 MW gyrotron prototypes.

The experimental demonstration of a W-band gyrotron backward-wave oscillator (gyro-BWO) using both thermionic cusp electron gun and helically corrugated waveguide will be presented. The cusp gun is designed to generate an axis-encircling electron beam of 1.5 A at 40 kV with an adjustable velocity ratio of up to 3.0. The beam had a simulated axial velocity spread (Δv z /v z ) of ∼8% and alpha spread (Δ α /α) of ∼10%. The beam had an averaged radius of 0.35 mm and beam thickness of 0.05 mm which is ideal to drive sub-mm wave gyro-devices under investigation. The gyro-BWO has been experimentally measured and the latest results will be presented.

The experimental demonstration of a gyrotron backward wave oscillator (gyro-BWO) using a cusp electron gun and helically corrugated waveguide will be presented. Operating in the W-band frequency range the gyro-BWO is predicted to output ∼10kW with a frequency tuning range of 85–104 GHz at 18% electronic efficiency before the energy recovery. The annular axis-encircling electron beam has been experimentally measured to show a 1.5 A, 40 kV beam with velocity ratio up to 1.56 at 1.65 T. Preliminary microwave radiation has been measured over a frequency range of 92 to 100 GHz.

The experimental demonstration of a W-band gyro-BWO using both thermionic cusp electron gun and helically corrugated waveguide will be presented. A cusp gun uses a non-adiabatic magnetic field reversal to obtain azimuthal motion on an electron beam resulting in an annular shaped, axis-encircling beam. The cusp gun was designed to generate a beam of 1.5A at 40kV with an adjustable velocity ratio of up to 3.0. The beam had a simulated axial velocity spread of ∼8% and alpha spread of ∼10%. The beam had an averaged radius of 0.35mm and beam thickness of 0.05mm which is ideal to drive sub-mm wave gyro-devices under investigation. The gyro-BWO has been constructed and designed to produce pulsed millimeter wave output radiation in the frequency range 84GHz to 104GHz.

Presented in this paper are the results of a 10 kW W-Band Gyro-BWO based on a helically corrugated interaction region and novel cusp electron gun. Microwave measurements of the helically corrugated interaction region are shown to give a low loss of 1dB over the frequency region of interest (84-104 GHz). The measured dispersion was found in good agreement with the analytically calculated and numerically simulated dispersions. The design and simulation results of the cusp electron gun of the Gyro-BWO device are given in this paper.

Presented in this paper is the design of a W-Band Gyro-BWO with a helically corrugated waveguide and a cusp electron gun. The interaction region has been constructed with good accuracy and microwave results measured using a vector network analyzer are given. The microwave dispersion agrees well with analytical and numerical theory. The transmission loss of this helically corrugated waveguide was measured to be ~1dB over the frequency range (84 - 104GHz). A cusp electron gun has been designed to generate a 1.5A, 40kV electron beam with an adjustable pitch angle (α) of up to 3. The beam was optimized through numerical simulation with an axial velocity spread, ΔVz/Vz, of 7% and Δα/α, of 10.4% at α=1.65. From simulation of the beam-wave interaction the maximum output power from the Gyro-BWO was predicted to be 10kW (CW) at 17% efficiency, with a 3dB frequency tuning range of ~84-104GHz.

This paper presents the design and simulation of a 390 GHz harmonic gyrotron operating with a TE71 mode at the 7th electron cyclotron harmonic of a large orbit electron beam from a cusp electron gun. The electron beam has an energy of 40 keV, beam current of 1.5 A, an adjustable pitch alpha from 1 to 2 with a minimum beam velocity spread and scalloping in the beam trajectory. Interaction region based on cylindrical waveguide with smooth inner surface and slotted structures have been studied. Theoretical analysis and numerical simulation results of this source operating at THz frequencies are presented.

Summary form only given. Neon and argon were used as load gas for the Z-pinch experiments on the "yang" accelerator at IFP. And different sets of nozzles were tried out. An ultrafast multi-frame soft X-ray CCD camera was used in these experiments, which can get 10 frames with 10 ns time interval of pinch process at each pinch experiment. Time-integral X-ray pinhole camera and visible streak camera were used in these experiments, too. A laser shearing interferometer (532 nm) was used to catch the image of plasmas. The formation of the initial plasma and discharge channels were observed. Instability was found in the late part of pinch process. In addition shorten rise time of load current and better initial gas puff distribution will reduce these instabilities, make plasma column to compress more quickly and efficiently. More than 1 kJ and 20 GW soft X-ray radiation pulse was detected. Furthermore, more than 4times 107 cm/s imploding speed, and about 12 to 20 compression ratio of plasma column had been obtained. The results and phenomena of these experiments were discussed in this article