scholarly journals Simultaneous feedback control of toroidal magnetic field and plasma current on MST using advanced programmable power supplies

2020 ◽  
Vol 2 (3) ◽  
pp. 035012
Author(s):  
I R Goumiri ◽  
K J McCollam ◽  
A A Squitieri ◽  
D J Holly ◽  
J S Sarff ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Feedback Control ◽  
Toroidal Magnetic Field ◽  
Power Supplies ◽  
Plasma Current

Development of a novel spiral antenna system for low loop voltage current start up atSteady State Superconducting Tokamak(SST-1).

2021 ◽  
Author(s):  
Debjyoti Basu ◽  
D Raju ◽  
Raj Singh ◽  
Aparajita Mukherjee ◽  
Manoj Patel ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Antenna System ◽  
Toroidal Magnetic Field ◽  
Vacuum Vessel ◽  
Plasma Current ◽  
Test Results ◽  
Spiral Antenna ◽  
Start Up ◽  
Superconducting Tokamak

Abstract In general, superconducting tokamaks require low loop voltage current start up for the safety purpose of its poloidal field coils. The loop voltage inside the vacuum vessel of Steady-state Superconducting Tokamak (SST-1) is low in nature since its central solenoid is located outside the cryostat. The low loop voltage current start up of the SST-1 is routinely performed by Electron Cyclotron Resonance (ECR) method at the toroidal magnetic field Bt=1.5T(first harmonic) and 0.75T(second harmonic). Recently, an alternative RF based plasma current start up system had been planned for operating the machine specially for higher toroidal magnetic field regime 1.5T ≤ Bt ≤3T. The system is already developed based on an antenna system, made of series combinations of two at spiral antenna, to assist plasma current start up at lower inductive electric field. It is already tested and installed in SST-1 chamber. The system testing had been performed without background magnetic field within frequency regime 35-60MHz at present. The test results show that it can produce electron density ne ≈1016m-3 measured by the Langmuir probe in expense of 500W RF power. The spectroscopy results indicate that its capability to produce plasma density higher than 1013 m-3 and electron temperature Te = 2 -6eV. In addition, it also shows that the presence of turbulent electric field of the order of 106V/m at antenna center and finite anomalous temperature of neutral particles. Calculations show that the obtained density is enough for SST-1 low loop voltage plasma breakdown. The antenna system is also capable to produce plasma at higher frequencies. This article will discuss the development of the prototype and the installed antenna system along with their test results in detail.

scholarly journals Измерение мощности радиационных потерь и эффективного заряда плазмы на токамаке Глобус-М2

2021 ◽  
Vol 47 (2) ◽  
pp. 9
Author(s):  
Е.А. Тюхменева ◽  
Н.Н. Бахарев ◽  
В.И. Варфоломеев ◽  
В.К. Гусев ◽  
Н.С. Жильцов ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electron Density ◽  
Central Region ◽  
Input Power ◽  
Toroidal Magnetic Field ◽  
Plasma Current ◽  
Radiation Losses ◽  
Radiated Power ◽  
Wide Range ◽  
Measurement Results

This paper presents the measurement results of the radiated power Prad and the effective ion charge Zeff in a toroidal magnetic field of up to 0.7 T and a plasma current of up to 300 kA for a wide range of electron density, which were first obtained on the Globus-M2 tokamak. An analysis of the results demonstrated that the content of radiation losses relative to the input power decreased in the Globus-M2 tokamak compared to the Globus-M tokamak, and the measured profiles of Prad had a strong dip in the central region. In addition, a decrease of the effective ion charge Zeff with increasing electron density was observed.

Features of the Radial and Axial Distributions of the Toroidal Magnetic Field in the Axial Jet Ejection at the PF-3 Facility

2021 ◽  
Vol 47 (9) ◽  
pp. 912-937
Author(s):  
V. I. Krauz ◽  
K. N. Mitrofanov ◽  
V. V. Myalton ◽  
I. V. Il’ichev ◽  
A. M. Kharrasov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Toroidal Magnetic Field

THE ROTATIONAL EFFECT OF MAGNETIC PARTICLES ON CELLULAR APOPTOSIS BASED ON FOUR ELECTROMAGNET FEEDBACK CONTROL SYSTEM

2021 ◽  
pp. 2150045
Author(s):  
Jia Ji Lee ◽  
Chang Hong Pua ◽  
Misni Misran ◽  
Poh Foong Lee
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Control System ◽  
Feedback Control ◽  
Cell Apoptosis ◽  
Magnetic Particles ◽  
Drug Carriers ◽  
Feedback Control System ◽  
Rotational Effect ◽  
Dynamic Magnetic Field

Objectives: Magnetic drug targeting offers the latest popular alternative option to deliver magnetic drug carriers into targeting region body parts through manipulation of an external magnetic field. However, the effectiveness of using an electromagnetic field to manipulate and directing magnetic particles is yet to be established. Methods: In this paper, a homemade cost-effective electromagnet system was built for the purpose of studying the control and directing the magnetic drug carriers. The electromagnet system was built with four electromagnetic sources and tested the capability in directing the particles’ movement in different geometry patterns. Besides that, the creation of the self-rotation of individual magnetic particle clusters was achieved by using fast switching between magnetic fields. This self-rotation allows the possibility of cell apoptosis study to carry out. The system was constructed with four electromagnets integrated with a feedback control system and built to manipulate a droplet of commercially available iron (II, III) oxide nanoparticles to steer the magnetic droplet along different arbitrary trajectories (square, circle, triangle, slanted line) in 2-dimensional. Results: A dynamic magnetic field of 25 Hz was induced for magnetic nanoparticles rotational effect to observe the cell apoptosis. A profound outcome shows that the declining cell viability of the cell lines by 40% and the morphology of shrinking cells after the exposure of the dynamic magnetic field. Conclusion: The outcome from the pilot study gives an idea on the laboratory setup serves as a fundamental model for studying the electromagnetic field strength in applying mechanical force to target and to rotate for apoptosis on cancer cell line study.

Nonaxisymmetric Instabilities of a Toroidal Magnetic Field in a Rotating Sphere

2003 ◽  
Vol 585 (2) ◽  
pp. 1124-1137 ◽  
Author(s):  
Keke Zhang ◽  
Xinhao Liao ◽  
Gerald Schubert
Keyword(s):  
Magnetic Field ◽  
Toroidal Magnetic Field ◽  
Rotating Sphere

New Lens System Using Toroidal Magnetic Field for Intense Ion Beam

1977 ◽  
Vol 16 (3) ◽  
pp. 491-496 ◽  
Author(s):  
Akihiro Mohri ◽  
Kazunari Ikuta ◽  
Junji Fujita
Keyword(s):  
Magnetic Field ◽  
Ion Beam ◽  
Toroidal Magnetic Field ◽  
Lens System
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