INVESTIGATION OF NOISE SIGNALS IN PULSED DISCHARGE DEVICES

The mechanisms responsible for emission of electromagnetic noise signals by pulsed discharge circuits have been studied. The investigation has led to an improved discharge system which minimizes the production of noise signals through the use of a photon-triggered pulse generator and coaxial or parallel plate current-carrying leads. The residual noise signals are due principally to the spark-gap switches required in the discharge system. The discharge current in the improved system is measured with a simple and inexpensive Rogowski coil apparatus into which delay lines are incorporated. This measuring apparatus provides oscillograms of the discharge current that are completely noise free, and obviates the use of costly isolation transformers and screened rooms for producing clean oscillograms. The frequency response of the measuring apparatus is flat to 5 Mc and 3 dB down at 7 Mc.

Download Full-text

Understanding of TiO2 catalysis mechanism in underwater pulsed discharge system: Charge carrier generation and interfacial charge-transfer processes

Chemosphere ◽

10.1016/j.chemosphere.2020.129249 ◽

2021 ◽

Vol 267 ◽

pp. 129249

Author(s):

Lijuan Duan ◽

Shuai Rao ◽

Dongxing Wang ◽

Kuifang Zhang ◽

Hongyang Cao ◽

...

Keyword(s):

Charge Transfer ◽

Charge Carrier ◽

Pulsed Discharge ◽

Carrier Generation ◽

Interfacial Charge Transfer ◽

Discharge System ◽

Transfer Processes ◽

Catalysis Mechanism ◽

Interfacial Charge

Download Full-text

CALCULATIONS OF ION TRAJECTORIES AT MAGNETOPLASMA SEPARATION AND EXPERIMENTS WITH POLYATOMIC GASES

Acta Polytechnica ◽

10.14311/ap.2017.57.0071 ◽

2017 ◽

Vol 57 (1) ◽

pp. 71-77

Author(s):

Vladimir Yuferov ◽

Sergey Shariy ◽

Tetiana Tkachova ◽

Vyacheslav Katrechko ◽

Alexander Svichkar ◽

...

Keyword(s):

Discharge Current ◽

Energy Input ◽

Pulsed Discharge ◽

Polyatomic Gases ◽

Constant Energy ◽

Mixture Separation ◽

Low Emission ◽

Vibrational Levels ◽

Nonlinear Character

Calculated trajectories of ions with different masses, indicating the possibility of a mixture separation, are obtained. Comparative experiments for plasma of monatomic and polyatomic gases (Ar, N<sub>2</sub>, CO<sub>2</sub>), upon combination of pulsed discharge with a stationary one with incandescent cathode, are carried out. The oscillograms of discharge current and voltage at low emission currents and a constant energy input show that energy is spent on other processes different from ionization. With an increase of emission current, the nonlinear character of the discharge current and voltage, which may be indicative of the role of dissociation and vibrational levels in energy consumption, is observed. In addition, there is connection between the number of atoms in molecule and the values of maximum discharge current and the pressure of injected gas.

Download Full-text

Analysis of shock wave induced by underwater pulsed discharge using discharge current interception

Journal of Applied Physics ◽

10.1063/1.5143080 ◽

2020 ◽

Vol 127 (14) ◽

pp. 143301

Keyword(s):

Shock Wave ◽

Discharge Current ◽

Pulsed Discharge ◽

Wave Induced

Download Full-text

Discharge current development in two-electrode spark gap switches

IEEE Transactions on Plasma Science ◽

10.1109/tps.2002.1003874 ◽

2002 ◽

Vol 30 (1) ◽

pp. 301-309 ◽

Cited By ~ 5

Author(s):

H. Golnabi

Keyword(s):

Discharge Current ◽

Current Development ◽

Spark Gap

Download Full-text

Expansion of cylindrical tubular workpieces on high-voltage magnetic-pulse installation with controlled vacuum discharger

Electrical Engineering & Electromechanics ◽

10.20998/2074-272x.2021.3.07 ◽

2021 ◽

pp. 42-46

Author(s):

L. A. Ljutenko ◽

V. M. Mikhailov

Keyword(s):

Energy Storage ◽

High Voltage ◽

Discharge Current ◽

High Probability ◽

Rogowski Coil ◽

Magnetic Pulse ◽

Pressure Amplitude ◽

Charge Voltage ◽

Capacitive Energy Storage ◽

Current Pulses

Purpose. An experimental verification of the existence of a range of values for the parameters of the capacitive energy storage of the magnetic-pulse installations with controlled vacuum discharger, in which, with a high probability, there is a «cut» of the discharge current pulses and the expansion of cylindrical thin-walled tubular workpieces using an external coil. Methodology. High voltage magnetic-pulse installation of NTU «KhPI» with controlled vacuum discharger, multiturn coil with inside dielectrical die and inside aluminum alloy workpiece are used. The capacitance and charge voltage of capacitive energy storage are changed. Discharge current pulses are measured by Rogowski coil and the oscillograph. Results. Parts of complicated shape are made by expansion of cylindrical tubular workpieces with help of external coil. Pressed metallic tubular part is removable from inner dielectric rod. Originality. The frequency of «cut» pulse is defined by negative magnetic field pressure amplitude. It is shown that we must coordinate this frequency and charge voltage with capacitive storage parameters by high probability of pulse «cut». Practical value. It is shown how to use installations with controlled vacuum dischargers in magnetic forming technology based on «cut» pulses.

Download Full-text

Research of Dual Spark Gap Application for High Voltage Pulse Generator

10.1109/ickii51822.2021.9574781 ◽

2021 ◽

Author(s):

Yong-Dong Chang

Keyword(s):

High Voltage ◽

Voltage Pulse ◽

Pulse Generator ◽

High Voltage Pulse ◽

Spark Gap ◽

High Voltage Pulse Generator ◽

Voltage Pulse Generator

Download Full-text

Heating and Acceleration of Ceramic Particles in 20-kA Pulsed Plasma

Thermal Spray 1998: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc1998p1501 ◽

1998 ◽

Author(s):

M. Miyamoto ◽

T. Sakuta ◽

M. Tago

Keyword(s):

Melting Point ◽

Plasma Spraying ◽

Particle Velocity ◽

Discharge Current ◽

Particle Temperature ◽

Pulsed Plasma ◽

Pulsed Discharge ◽

Ceramic Particles ◽

Plasma Mode ◽

Alumina Particles

Abstract Plasma spraying is gradually becoming an important technique in the material processing field, if it would give additional value to the process by allowing the area and the thickness of the deposited film to be controlled. Plasma sources for heating and accelerating the high melting point (HMP) ceramic particles have been produced untiI now in a continuous D.C. plasma mode[l], [21 However, we would like to propose the application of a pulsed plasma produced with extremely large currents of tens of kA to plasma spraying. Our experiments were conducted with a specially developed plasma torch with a pulsed discharge current with a 24 kA peak and a 400 micro-second duration. The pulsed discharge current was provided by a capacitor bank with a maximum energy of 14 kJ. The simultaneous, in-fIight measurements[3] of particle temperature, velocity and size was carried out for alumina particles injected into the pulsed plasma. The results that we have obtained, showed that the surface temperature of the alumina particles reached 2,700 to 3,300 K which was considerably higher than the melting point of alumina. Particle velocity was found to be around 200 m/s which is comparable to particle velocity in the D.C. plasma mode. The details of the coating formed on the substrate with one shot of pulsed plasma were investigated with Scanning Electro-Microscopy(SEM). The experimental results have confirmed the applicability of pulsed plasma to the spraying of refractory materials.

Download Full-text