High frequency pulsation of high-voltage gas discharges
Physical mechanisms of high frequency current pulsations of high-voltage discharges at negative needle - flat anode and flat cathode - flat anode geometry are presented. It is shown for the first time that their nature is the same as a nature of negative corona HF current pulsations.
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irk-123456789-797942015-04-05T03:02:28Z High frequency pulsation of high-voltage gas discharges Chyhin, V. Low temperature plasma and plasma technologies Physical mechanisms of high frequency current pulsations of high-voltage discharges at negative needle - flat anode and flat cathode - flat anode geometry are presented. It is shown for the first time that their nature is the same as a nature of negative corona HF current pulsations. Представлено механізми високочастотних пульсацій струму високовольтних розрядів при геометрії негативне вістря – плоский анод і плоский катод – плоский анод. Вперше показано, що їх природа є тією ж, що і природа ВЧ пульсацій струму негативної корони. Представлены механизмы высокочастотных пульсаций тока высоковольтных разрядов при геометрии отрицательное острие – плоский анод и плоский катод – плоский анод. Впервые показано, что их природа есть той же, что и природа ВЧ пульсаций тока отрицательной короны. 2005 Article High frequency pulsation of high-voltage gas discharges / V. Chyhin // Вопросы атомной науки и техники. — 2005. — № 2. — С. 185-187. — Бібліогр.: 4 назв. — англ. 1562-6016 PACS: 52.80.Hc, 52.35.-g, 52.65.-y, 51.50.+v http://dspace.nbuv.gov.ua/handle/123456789/79794 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Low temperature plasma and plasma technologies Low temperature plasma and plasma technologies Chyhin, V. High frequency pulsation of high-voltage gas discharges Вопросы атомной науки и техники |
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Physical mechanisms of high frequency current pulsations of high-voltage discharges at negative needle - flat anode and flat cathode - flat anode geometry are presented. It is shown for the first time that their nature is the same as a nature of negative corona HF current pulsations. |
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Article |
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Chyhin, V. |
| author_facet |
Chyhin, V. |
| author_sort |
Chyhin, V. |
| title |
High frequency pulsation of high-voltage gas discharges |
| title_short |
High frequency pulsation of high-voltage gas discharges |
| title_full |
High frequency pulsation of high-voltage gas discharges |
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High frequency pulsation of high-voltage gas discharges |
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High frequency pulsation of high-voltage gas discharges |
| title_sort |
high frequency pulsation of high-voltage gas discharges |
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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2005 |
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Low temperature plasma and plasma technologies |
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http://dspace.nbuv.gov.ua/handle/123456789/79794 |
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High frequency pulsation of high-voltage gas discharges / V. Chyhin // Вопросы атомной науки и техники. — 2005. — № 2. — С. 185-187. — Бібліогр.: 4 назв. — англ. |
| series |
Вопросы атомной науки и техники |
| work_keys_str_mv |
AT chyhinv highfrequencypulsationofhighvoltagegasdischarges |
| first_indexed |
2025-07-06T03:46:23Z |
| last_indexed |
2025-07-06T03:46:23Z |
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1836867737428688896 |
| fulltext |
HIGH FREQUENCY PULSATION
OF HIGH-VOLTAGE GAS DISCHARGES
V. Chyhin
National university “Lvivska polytechnika”, е-mail: vchygin@ polynet.lviv.ua
Physical mechanisms of high frequency current pulsations of high-voltage discharges at negative needle - flat anode and
flat cathode - flat anode geometry are presented. It is shown for the first time that their nature is the same as a nature of
negative corona HF current pulsations.
PACS: 52.80.Hc, 52.35.-g, 52.65.-y, 51.50.+v
A transition of low-frequency Trichel pulses (TP) of
the negative corona [1] in the high-frequency current
pulsation (HFCP) has been recently recorded in hydrogen
[2]. At a length of the point-to-plane gap d = 20 mm, gas
pressure of 12,5 kPa and the point radius r0 = 0,15 mm at
the TP finishing the HFCP with a frequency of 1-10 MHz
arises (Fig.1a). It was recognized [2] that “the mechanism
of these oscillations has yet to be understood”. The similar
phenomenon has been observed by the optical method
earlier [3]. The HFCP have been registered also in [4]
(Fig.1b,c). A complete theory of the HF pulsation of the
high-voltage discharge plasma is not known in a literature.
We have first disclosed [1] that under certain conditions
the corona HFCP can accept three shapes – the 1-st after-
peak type, the 2-nd tail type and the 3-rd outside of the TP
type. In this work, to clarify a nature of the HF pulsation
the detailed analysis of a behavior of the space-temporal
distribution of charges and field in the discharge plasma in
N2 of atmospheric pressure with O2 in a wide region of the
concentration (C%,O2) is carried out.
Fig. 1. Temporal dependences of gas discharge current with HF pulsations measured in a) [2] and b,c) [4]
1. CHARACTERISTICS OF MEASURED HFCP
The shape of the HF pulse (Fig.1a) is similar to the
shape of the TP pulse [1] with the considerably short
duration. Temporal dependences of the discharge current
measured in nitrogen and in nitrogen-methane mixture [4]
include the HF pulsation with amplitudes damped to the
constant current (Fig.1b) and with the current exponential
increase right up to the breakdown (Fig.1c).
2. MODELLING RESULTS AND DISSCUSION
A simulation basis is the solution of continuity equa
tions for three types of charges, supplemented by the
Poisson’s equation for an electrical field in a quasi-two-
dimensional space [1]. Typical temporal current depen
dences of the point-to-plane corona and the transition
discharge in nitrogen are submitted in Figures 2-5. One
can see that under certain conditions the calculated HFCP
are similar to measured ones (Fig.1). Strong HFCP
dependences on the O2 concentration (Fig.2a,b, 3, 4a), the
applied voltage U (Fig.2b) and the external resistance R
(Fig.2d, 4b) are evident. The 3-rd type of the HFCP
appears outside of the peak part of the TP at a lowering
C%,O2 up to 0.25% (Fig.2a), 0.5% (Fig.2b) and 0.352%
(Fig.3). Lower C%,O2 lead to the breakdown (Fig.2 -
<0.05%, Fig.3 - <0.35%, Fig.4 - <0.3%). A transition to
the breakdown can occur immediately after the first TP
peak (Fig.2,3) and without the last (Fig.4). An increase of
the C%,O2 slows down an appearance of the HFCP and
reduces its frequency (Fig.4a). An increase of the R delays
this process as well and smoothes the HFCP (Fig.4b).
Fig.4c demonstrates weak initial amplitudes of the HFCP
(0-8,5 μs) and their sharp increase in the next short time
interval (9,6–10 μs). Numerals 1-6 indicate extremums for
which the correspondent spatial distribution of positive
charges in the cathode plasma are depicted in Fig.4d,e.
Apparently, a decrease of the positive ion density in its
tail distribution (Fig.4e) at the moment 5 of the pulse
maximum is much higher in comparison with its decrease
at the initial moment 2 (Fig.4d). So, a screening efficiency
of positive ions in the corona plasma increases essentially
in course of time.
In the time region A (Fig.5a) the inter-pulse current
rises above zero, and in the region B the HF pulsation is
discontinued and the current increases sharply to the
break-down. Correspondent to the region A the density of
positive ions in the tail distribution (Fig.5b) is essentially
reduced in points 3,4 of the current maximum – in anti
phase with an increase of the density near the surface. In a
transition to the break-down (region B, Fig.5a) the density
of positive ions and electrons approaches one to other in
the full cathode region (Fig.5c,d), creating a homogeneous
plasma medium before the breakdown.
Problems of Atomic Science and Technology. Series: Plasma Physics (11). 2005. № 2. P. 185-187 185
t, μs
I
I
a)
c)
b)
Fig.2. d = 0.6 cm: a) r0 = 0.0035 cm, U = 2200 V, R = 1×106 Ω, C%,O2 - numerals; b,c,d) r0 =0.004 cm:
b) R =5×104 Ω, U and C%,O2 - numerals; c,d) U = 2400 V, C = 0, c) R = 5*103 Ω, d) R – numerals, Ω
Fig.3. d = 0.6 cm, r0 = 0.004 cm, U = 2300 V and R = 1 MΩ ; C%,O2 is designated by numerals
Fig.4. d = 0.6 cm, r0 = 0.004 cm, U = 2300 V; a,c) R =1×104 Ω, b) C = 0;
d,e) dependences of relative positive ion density np(x)/np(0) on the distance x from the cathode
186
0,255
0,2
0,25
0,29
100
50
6 7
I,
μА
t, s
d)
t, s2
25
I,
m
А
b)I,
μА
t, s
1000
1
2400, 0.05
2400, 0.5
2300, 0.5
a) c)
2
1
5*103
5*104
5*105
0.3
0
0.35
0.1
0.3550.370.451
0.352
10
0
I,
μА
t, s4 8
b) 104
106
107
1
10
100
10
d)1 e)1
0.5
1
0.5
4
2 3 5
6
0.005 0.01 0.005 0.01
t, s
I,
μА
5000
0
a)
0 20 40 60
C=0 C=0.3C=0.25
3
c)
200
84
6
5
2
4
1
C=0
x, cm
Based on obtained results, we can assert that a reason
of an origin of the HF current pulsation in transition
discharge stages in the non-uniform high-voltage field is
its periodic screening in the cathode area by positive ions,
in other words, mainly by a “self-screening”. A feed-back
of the ion density on the cathode surface and the electric
field in a tail of their distribution creates the negative
current-voltage characteristic of the cathode layer. Such
picture exists at the low current, when in the surface layer
the ionization region is very thin. At an increase of the
current the ionization layer gradually expands in a
direction of the drift space and conditions for the plasma
origin are created (Fig.5c,d), so the HF current pulsation
disappears. Further, depending on a relation of internal
electrical and gas parameters, the applied voltage and the
external resistance, earlier or later the break-down arises
(Fig.2-5), or the current is restricted by the constant value
(Fig.2,3). A maintaining of the glow discharge in pure
electropositive gases is complicated (Fig. 2-5, C=0). A
presence of the slow negative component in the discharge
space can change this HF process of screening, slow down
the break-down (Fig.4a) or lead to a complete
Fig.5. Data is the same as in Fig.4, C=0
blocking of the discharge (Fig.2b - >0.5%, Fig.3 - >1%).
An appearance of the HFCP in the plane discharge
geometry (Fig.1b,c) was considered [4] solely due to
avalanches reached an anode or positive ions - a cathode.
In our opinion, a relative comparison of these results is
possible at a consideration of the corona cathode field as
homogeneous concerning an influence on dynamics of
avalanches. In both cases their development is stopped in
the end of the compared region – the anode [4] or the
corona plasma sheath. Then, it is possible to consider a
series of avalanches [4] as pulsations of the ion stream to
the surface with corresponding current change in the
circuit.
Summing, it is possible to emphasize that the HFCP of
discharges are satisfactorily described by Townsend’s
mechanisms without attracting of additive volumetric
streamer processes. The offered theory and numerical
model of the HFCP enable to increase essentially a
reliability of an ascertainment of the high-voltage
discharge plasma nature, in particular, of the corona, the
glow and the break-down.
REFERENCES
1. V. Chyhin // Problems Atomic Science and
Technology. Series: Plasma Physics (10), 2005, № 1,
p. 178-180.
2. A. Zahoranova, M. Cernak, H. Wagner // Czech.
J.Phys. 1999, v. 49, N 12, p. 1721-1735.
3. T. Reess et all. // J.Phys. D, 1995, v. 8, p. 2308–
2312.
4. H. Raether. Electron avalanches and breakdown in
gases. M.: “Mir”, 1968, p. 300.
ВЫСОКОЧАСТОТНЫЕ ПУЛЬСАЦИИ ВЫСОКОВОЛЬТНЫХ ГАЗОВЫХ РАЗРЯДОВ
В. Чигинь
Представлены механизмы высокочастотных пульсаций тока высоковольтных разрядов при геометрии
отрицательное острие – плоский анод и плоский катод – плоский анод. Впервые показано, что их природа есть
той же, что и природа ВЧ пульсаций тока отрицательной короны.
ВИСОКОЧАСТОТНІ ПУЛЬСАЦІЇ ВИСОКОВОЛЬТНИХ ГАЗОВИХ РОЗРЯДІВ
В. Чигінь
187
b)A
1
2
3
4
5
6
x, cm
n,
c
m
-3
1011
0.00
4
1012
0.00
8
d)c)B B
n,
c
m
-3
1012
1013
x, cm0.01 0.02 0.01 0.02
14
p
14.1
14.5
15 15
14.5
14.1
n
8.8 9 9.2
1 2
3
4
5 6
t, s
I,
m
А
1000
1210
a) B
A
A
Представлено механізми високочастотних пульсацій струму високовольтних розрядів при геометрії негативне
вістря – плоский анод і плоский катод – плоский анод. Вперше показано, що їх природа є тією ж, що і природа
ВЧ пульсацій струму негативної корони.
188
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