Over 55kV//spl mu/s, dv/dt turn-off characteristics of 4kV-static induction thyristor for pulsed power applications

Shimizua,; Sekiya,; Iida,; Imanishi,; Kimura,; Nishizawa,

doi:10.1109/wct.2004.239988

“…The studied ns-discharge has been developed in our lab. and composed of a custom-design ns pulse generator based on an inductive energy storage circuit with a single 4 kV static induction thyristor [62]. A single thyristor approach provides numerous benefits including high discharge repeatability and high overall robustness.…”

Section: Methodsmentioning

confidence: 99%

Diagnostics of a nanosecond atmospheric plasma jet. Electron and ro-vibrational excitation dynamics

Britun¹,

Christy²,

Gamaleev³

et al. 2022

Plasma Sources Sci. Technol.

View full text Add to dashboard Cite

Atmospheric repetitive He discharge with 10 ns current peak width and 3 × 10 11 V s−1 voltage front rise working in jet geometry is studied. The first part of the study is devoted to electrical and optical discharge characterization including voltage-current behavior, emission dynamics, as well as ro-vibrational dynamics of N2, N 2 + and OH molecules. It is found that He atoms get excited at the very early stage, as a result of ionization wave formation. This process follows by excitation of O, N2 and N 2 + . It is also shown that a rather small (0.1%–1%) air admixtures facilitate gas breakdown, as revealed by shortening of the discharge current risetime. The rotational excitation of N 2 + always overtakes He excitation by about 5 ns, with rotational temperature peaking at about 650 K and decaying afterwards, whereas rotational temperature of N2 always remains constant equal to about 300 K. This value is associated with gas kinetic temperature since the electron-rotational (e-R) excitation process is too slow, so it cannot be activated during the plasma phase and no additional change in rotational excitation of N2 happens. Nitrogen molecules remain vibrationally excited in the discharge, post-discharge and jet areas after the plasma pulse which is likely a result of ionization wave propagation. Upon water vapor injection the apparent OH rotational distributions reveal double Boltzmann slope representing thermalized and non-thermalized OH groups. Rotational temperature of the thermalized group correlates with the one of N 2 + showing, however, much longer relaxation time, whereas for the non-thermalized group it remains above 1 eV at all conditions. The obtained results confirm that the studied ns- discharge is a good candidate for temperature-sensitive applications, such as the bio-sample treatment. Further analysis related to the ionization waves, electron density and electric field behavior is undertaken in the second part.

show abstract

“…2c, which is effective to make much of the nano-pulsed effect beside of the pulsed electrode; the forward voltage impact ionization to generate ions and radicals, and the instant reverse pulsed powered reaction. A high speed switching 4 kV-Static Induction Thyristor (SIThy) and an Induction Energy Storage (IES) circuit, [14][15][16][17] known to configurate the small and compact pulsed power electric sources, were applied. The adopted pulse repetition rate was increased up to 5 kpps, 5 times higher than the experiment in Fig.…”

Section: Electrode Polarity Dependence Of Gas Generationmentioning

confidence: 99%

High-Efficient Hydrogen Generation Study by a Reverse Tailing Pulsed-Plasma Water Dissociation Applying Wet Electrode Method

Shimizu

¹

,

Borude

²

,

Tanaka

³

et al. 2022

J. Electrochem. Soc.

0

View full text Add to dashboard Cite

A pulsed power water dissociation method applying a couple of a porous-ceramic electrode, wetted with water, and an opposite dry electrode in atmospheric air was studied. The basic concept for this study is composed of “pulsed power activation of high-density water molecules at the porous electrode creepage” and “subsequent non-thermal equilibrium plasma reactions of these molecules diffusing into the low-density molecule air”. The deionized water (DIW) dissociation experiments were performed by applying the reverse tailing pulse (RTP) method, where the forward pulse voltage of 10 kV level with the rising up ratio (dV/dt) of 1011 V/s level is applied. To examine the electric polarity contribution, four kinds of reactors were studied. H2 was detected in one reactor which is composed of an anode electrode made by porous-ceramic, wetted with DIW, and a cathode electrode made from a dry fine-ceramic. The H2 generation efficiency, close to the theoretical prediction, was obtained when “Tanzanite” colored plasma was detected. These features may be due to the “RTP” reformation of the high-density water molecules in the wetted porous-electrode creepage and their continuous diffusion into the gas plasma space with the help of “Fick’s law of diffusion” and “pulsed ion wind”.

show abstract

“…A newly developed small-sized IES circuit which uses a semiconductor switch for the turn-off action [10] is used to generate repetitive nanosecond pulse discharges. This IES circuit enables the turn-off voltage rise-up rate (dv/dt) limit to be over several ten times higher than that of a conventional inverter that uses switching circuit technology, and enables the generation of a high rise-up voltage pulse.…”

Section: Ignition Systemmentioning

confidence: 99%

“…In addition, this circuit can operate with a low-voltage power supply such as a car battery. Details of this circuit and switching mechanism can be found elsewhere [10]. Electrical parameters are recorded by means of an oscilloscope (Hewlett Packard 5450A) with the help of a highvoltage probe (Tektronix P6015A) and current monitor (Pearson model 2872).…”

Section: Ignition Systemmentioning

confidence: 99%

“…In this paper, the ignition properties of combustible mixtures are investigated under various conditions using repetitive pulse discharges generated by a newly developed small-sized inductive energy storage (IES) circuit with a semiconductor switch being used for the turn-off action [10]. The IES circuit with a semiconductor switch was developed for pulsed power applications, such as plasma surface treatments, plasma sterilization and so on [10]. This study is the first time that this circuit has been applied to an ignition system.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Enhancement of ignition characteristics of lean premixed hydrocarbon–air mixtures by repetitive pulse discharges

Tanoue

¹

,

Hotta

²

,

Moriyoshi

³

2009

International Journal of Engine Research

9

0

View full text Add to dashboard Cite

A newly developed small-sized inductive energy storage (IES) circuit that uses a semiconductor switch for the turn-off action is successfully applied to an ignition system in spark ignition engines operating under lean fuel–air ratios. This IES circuit can generate repetitive nanosecond pulse discharges. Experiments are conducted by means of a spherically expanding flame configuration for C3H8–air mixtures under various conditions. Findings show the investigated ignition system improves the inflammability of lean combustible mixtures in terms of extended flammability limits, shorted ignition delay time, and extended dilution limits, compared with conventional spark ignition systems.

show abstract

Over 55kV//spl mu/s, dv/dt turn-off characteristics of 4kV-static induction thyristor for pulsed power applications

Cited by 13 publications

References 2 publications

Diagnostics of a nanosecond atmospheric plasma jet. Electron and ro-vibrational excitation dynamics

Diagnostics of a nanosecond atmospheric plasma jet. Electron and ro-vibrational excitation dynamics

High-Efficient Hydrogen Generation Study by a Reverse Tailing Pulsed-Plasma Water Dissociation Applying Wet Electrode Method

Enhancement of ignition characteristics of lean premixed hydrocarbon–air mixtures by repetitive pulse discharges

Contact Info

Product

Resources

About