Two-strap RF antenna in Uragan-2M stellarator
A unshielded two-strap antenna had been installed in Uragan-2M. A vacuum chamber inner walls conditioning regime with the two-strap antenna is studied in a weak magnetic field. Plasma with the density nₑ~ (0.2…0.95)·10¹²сm⁻³ and sustained. The RF frequency was f₀~5 MHz, RF plasma was sustained in st...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2020
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| Zitieren: | Two-strap RF antenna in Uragan-2M stellarator / A.V. Lozin, Yu.V. Kovtun, V.E. Moiseenko, S.M. Maznichenko, M.M. Kozulia, V.B. Korovin, A.N. Shapoval, E.D. Kramskoy, R.O. Pavlichenko, N.V. Zamanov, M.M. Makhov, A.Yu. Krasyuk, Y.V. Siusko, A.I. Tymoshenko, V.M. Listopad, T. Wauters, Ye. Kazakov, J. Ongena // Problems of atomic science and tecnology. — 2020. — № 6. — С. 10-14. — Бібліогр.: 21 назв. — англ. |
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Lozin, A.V. Kovtun, Yu.V. Moiseenko, V.E. Maznichenko, S.M. Kozulia, M.M. Korovin, V.B. Shapoval, A.N. Kramskoy, E.D. Pavlichenko, R.O. Zamanov, N.V. Makhov, M.M. Krasyuk, A.Yu. Siusko, Y.V. Tymoshenko, A.I. Listopad, V.M. Wauters, T. Kazakov, Ye. Ongena, J. 2023-11-27T19:35:16Z 2023-11-27T19:35:16Z 2020 Two-strap RF antenna in Uragan-2M stellarator / A.V. Lozin, Yu.V. Kovtun, V.E. Moiseenko, S.M. Maznichenko, M.M. Kozulia, V.B. Korovin, A.N. Shapoval, E.D. Kramskoy, R.O. Pavlichenko, N.V. Zamanov, M.M. Makhov, A.Yu. Krasyuk, Y.V. Siusko, A.I. Tymoshenko, V.M. Listopad, T. Wauters, Ye. Kazakov, J. Ongena // Problems of atomic science and tecnology. — 2020. — № 6. — С. 10-14. — Бібліогр.: 21 назв. — англ. 1562-6016 PACS: 52.55.Hc; 52.50.-b https://nasplib.isofts.kiev.ua/handle/123456789/194627 A unshielded two-strap antenna had been installed in Uragan-2M. A vacuum chamber inner walls conditioning regime with the two-strap antenna is studied in a weak magnetic field. Plasma with the density nₑ~ (0.2…0.95)·10¹²сm⁻³ and sustained. The RF frequency was f₀~5 MHz, RF plasma was sustained in stationery magnetic field B₀≈0.01 T, at hydrogen pressure range 3·10⁻³…3·10⁻² Pa. Введена в експлуатацію на Урагані-2М багатофункціональна неекранована двонапіввиткова антена. Відпрацьована можливість роботи двонапіввиткової антени в режимі чистки внутрішніх поверхонь вакуумної камери в слабкому магнітному полі. Плазма створювалась і підтримувалась густиною nₑ~ (0.2…0.95)·10¹²сm⁻³. За робочої частоти f₀~5 МГц ВЧ-плазма створювалась у стаціонарному магнітному полі B₀≈0.01 Tл за тиску водню 3·10⁻³…3·10⁻² Па. Введена в эксплуатацию на Урагане-2М многофункциональная неэкранированная двухполувитковая антенна. Отработана возможность работы двухполувитковой антенны в режиме чистки внутренних поверхностей вакуумной камеры в малом магнитном поле Плазма создавалась и поддерживалась с плотностью ne~ (0.2…0.95)·10¹²сm⁻³. При рабочей частоте f₀~5 МГц ВЧ-плазма создавалась в стационарном магнитном поле B₀≈0.01 Tл при давлении водорода 3·10⁻³…3·10⁻² Па. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under Grant Agreement № 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Magnetic confinement Two-strap RF antenna in Uragan-2M stellarator Двонапіввиткова антена стеларатора Ураган-2М Двухполувитковая антенна стелларатора Ураган-2М published earlier |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| title |
Two-strap RF antenna in Uragan-2M stellarator |
| spellingShingle |
Two-strap RF antenna in Uragan-2M stellarator Lozin, A.V. Kovtun, Yu.V. Moiseenko, V.E. Maznichenko, S.M. Kozulia, M.M. Korovin, V.B. Shapoval, A.N. Kramskoy, E.D. Pavlichenko, R.O. Zamanov, N.V. Makhov, M.M. Krasyuk, A.Yu. Siusko, Y.V. Tymoshenko, A.I. Listopad, V.M. Wauters, T. Kazakov, Ye. Ongena, J. Magnetic confinement |
| title_short |
Two-strap RF antenna in Uragan-2M stellarator |
| title_full |
Two-strap RF antenna in Uragan-2M stellarator |
| title_fullStr |
Two-strap RF antenna in Uragan-2M stellarator |
| title_full_unstemmed |
Two-strap RF antenna in Uragan-2M stellarator |
| title_sort |
two-strap rf antenna in uragan-2m stellarator |
| author |
Lozin, A.V. Kovtun, Yu.V. Moiseenko, V.E. Maznichenko, S.M. Kozulia, M.M. Korovin, V.B. Shapoval, A.N. Kramskoy, E.D. Pavlichenko, R.O. Zamanov, N.V. Makhov, M.M. Krasyuk, A.Yu. Siusko, Y.V. Tymoshenko, A.I. Listopad, V.M. Wauters, T. Kazakov, Ye. Ongena, J. |
| author_facet |
Lozin, A.V. Kovtun, Yu.V. Moiseenko, V.E. Maznichenko, S.M. Kozulia, M.M. Korovin, V.B. Shapoval, A.N. Kramskoy, E.D. Pavlichenko, R.O. Zamanov, N.V. Makhov, M.M. Krasyuk, A.Yu. Siusko, Y.V. Tymoshenko, A.I. Listopad, V.M. Wauters, T. Kazakov, Ye. Ongena, J. |
| topic |
Magnetic confinement |
| topic_facet |
Magnetic confinement |
| publishDate |
2020 |
| container_title |
Вопросы атомной науки и техники |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| title_alt |
Двонапіввиткова антена стеларатора Ураган-2М Двухполувитковая антенна стелларатора Ураган-2М |
| description |
A unshielded two-strap antenna had been installed in Uragan-2M. A vacuum chamber inner walls conditioning regime with the two-strap antenna is studied in a weak magnetic field. Plasma with the density nₑ~ (0.2…0.95)·10¹²сm⁻³ and sustained. The RF frequency was f₀~5 MHz, RF plasma was sustained in stationery magnetic field B₀≈0.01 T, at hydrogen pressure range 3·10⁻³…3·10⁻² Pa.
Введена в експлуатацію на Урагані-2М багатофункціональна неекранована двонапіввиткова антена. Відпрацьована можливість роботи двонапіввиткової антени в режимі чистки внутрішніх поверхонь вакуумної камери в слабкому магнітному полі. Плазма створювалась і підтримувалась густиною nₑ~ (0.2…0.95)·10¹²сm⁻³. За робочої частоти f₀~5 МГц ВЧ-плазма створювалась у стаціонарному магнітному полі B₀≈0.01 Tл за тиску водню 3·10⁻³…3·10⁻² Па.
Введена в эксплуатацию на Урагане-2М многофункциональная неэкранированная двухполувитковая антенна. Отработана возможность работы двухполувитковой антенны в режиме чистки внутренних поверхностей вакуумной камеры в малом магнитном поле Плазма создавалась и поддерживалась с плотностью ne~ (0.2…0.95)·10¹²сm⁻³. При рабочей частоте f₀~5 МГц ВЧ-плазма создавалась в стационарном магнитном поле B₀≈0.01 Tл при давлении водорода 3·10⁻³…3·10⁻² Па.
|
| issn |
1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/194627 |
| citation_txt |
Two-strap RF antenna in Uragan-2M stellarator / A.V. Lozin, Yu.V. Kovtun, V.E. Moiseenko, S.M. Maznichenko, M.M. Kozulia, V.B. Korovin, A.N. Shapoval, E.D. Kramskoy, R.O. Pavlichenko, N.V. Zamanov, M.M. Makhov, A.Yu. Krasyuk, Y.V. Siusko, A.I. Tymoshenko, V.M. Listopad, T. Wauters, Ye. Kazakov, J. Ongena // Problems of atomic science and tecnology. — 2020. — № 6. — С. 10-14. — Бібліогр.: 21 назв. — англ. |
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2025-11-27T07:49:48Z |
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2025-11-27T07:49:48Z |
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ISSN 1562-6016. ВАНТ. 2018. №6(130)
10 PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2020, № 6. Series: Plasma Physics (26), p. 10-14.
https://doi.org/10.46813/2020-130-010
TWO-STRAP RF ANTENNA IN URAGAN-2M STELLARATOR
A.V. Lozin1, Yu.V. Kovtun1, V.E. Moiseenko1, S.M. Maznichenko1, M.M. Kozulia1,
V.B. Korovin1, A.N. Shapoval1, E.D. Kramskoy1, R.O. Pavlichenko1, N.V. Zamanov1,
M.M. Makhov1, A.Yu. Krasyuk1, Y.V. Siusko1, A.I. Tymoshenko1, V.M. Listopad1, T. Wauters2
Ye. Kazakov2, J. Ongena2
1Institute of Plasma Physics NSC “Kharkov Institute of Physics and Technology”, Kharkiv, Ukraine;
2Laboratory for Plasma Physics, ERM/KMS, Brussels, Belgium
E-mail: Ykovtun@kipt.kharkov.ua
A unshielded two-strap antenna had been installed in Uragan-2M. A vacuum chamber inner walls conditioning
regime with the two-strap antenna is studied in a weak magnetic field. Plasma with the density
ne~(0.2...0.95)∙1012 сm-3 and sustained. The RF frequency was f0~5 MHz, RF plasma was sustained in stationery
magnetic field B0≈ 0.01 T, at hydrogen pressure range 3∙10-3...3∙10-2 Pa.
PACS: 52.55.Hc; 52.50.-b
INTRODUCTION
The biggest stellarator Wendelstein 7-X (W7-X) will
resume its work in early 2022 [1,2]. New installed
equipment will include the ion-cyclotron plasma heating
(ICRH) system [3, 4]. The ICRH system includes a two-
strap antenna which shape is fitted for the last closed
magnetic surface of the standard magnetic configuration.
This system is tunable and can operate at frequencies of
25...38 MHz.
In stellarator Uragan-2M (U-2M) plasma is created
and heated with radio-frequency (RF) methods at ion-
cyclotron frequency range during regular operation.
Single and double frame, crankshaft, three-half-turn, and
four strap antennas [4-8] were used in previous
experimental studies. Newly made the two-strap antenna
is recently installed at U-2M. Its shape is similar to W-7X
ICRH antenna and the main distinction is that it is just
smaller. The main research tasks for the U-2M two-half-
turn antenna are the RF discharge plasma production
(start-up) for further regular discharges, and plasma
sustain in different RF vacuum chamber wall
conditioning regimes.
The Uragan-3M (U-3M) and U-2M vacuum
chambers are RF conditioned in weak magnetic fields at
frequencies up to 10 MHz [6, 9, 10]. The conditioning
method was proposed in Ref. [11]. The frame and three-
half-turn antenna were used for wall conditioning at U-
2M in those experiments. Hence it will be interesting to
study RF conditioning discharge of the new two-strap
antenna. It will allow us to work out the possibility of
two-strap antenna usage in the conditioning regime and to
test the antenna, its units, and matching device while
working with plasma load.
The paper presents a multifunctional unshielded two-
strap antenna description and its first usage in wall
conditioning regime in U-2M. The two-strap antenna was
used to create target plasma later experiments [12].
1. EXPERIMENTAL SETUP
U-2M device is a mid-size stellarator (torsatron)
with twin helical coils l=2 having a small pitch angle,
m=4 helical field periods and the additional toroidal
field coils (Fig. 1) [5-8, 12-14]. The major torus radius
is R0=1.7 m, the average last closed flux surface minor
radius is ā ≈ 0.2 m. The maximum toroidal magnetic
field strength with respect to mechanical stresses is
2.4 T. The vacuum chamber is toroidal with inner radius
of rc = 0.34 m and volume Vс= 3.879 m3 (without
volumes of the vacuum ports); torus surface area is
S = 22.819 m2. The device chamber has 48 ports used
for diagnostics, gas puffing, vacuum pumping, etc. The
vacuum chamber is pumped with three turbomolecular
pumps TMN-500 with a pumping speed of 0.5 m3/s
equipped by the cryogenic (N2 liquid) traps.
The RF complexes Kaskad-1 (K1) and Kaskad-2
(K2) use its 0.7 MW RF generators to produce and heat
the plasma in pulses of 100 ms maximum duration with
frequency tuneable between pulses in the range
f = 1...20 MHz [15]. The K1 and K2 generators are of
the same design: they are autogenerators. Each
generator has four GI-26Apowerful tubes.
Fig. 1. Scheme of U-2M: I – Poloidal field coils;
II – Helical field coils;
III –Toroidal field coils numbered 1-16
2. TWO-STRAP ANTENNA
The two-strap antenna (Fig. 2) consists of two parallel
straps 60 mm wide and 600 mm long. The straps are made
of 2 mm thick stainless steel. The emitting parts of the
straps are adjusted to the plasma edge. They are placed
10 mm distance from the last closed magnetic surface for
U-2M magnetic configuration with кφ= 0.32 (Fig. 4). The
https://doi.org/10.46813/2020-130-010
mailto:Ykovtun@kipt.kharkov.ua
ISSN 1562-6016. ВАНТ. 2020. №6(130) 11
5 mm side edges of both straps are bent to inside along the
whole length to provide mechanical stiffness. The distance
between the straps in toroidal direction is 250 mm.
The antenna (Fig. 3,a) is installed in the R1 cross-
section between the toroidal coils 4 and 5 see (Fig. 1).
The RF feed-troughs (see Fig. 2) are placed at the top and
bottom R1 cross-section ports (see Fig. 3,a). To provide
the ability of various electric connections, the antenna has
four independent RF power feed-troughs which use
fluoroplastic F-4 as isolator material. Water cooling of the
RF power feed-troughs allows antenna usage in impulses
up to 0.5 s long. The input elements of antenna (Fig. 5)
feed-troughs are protected by quartz tubes (3 mm thick
and 35 mm diameter) to prevent breakdowns to the
chamber wall and creation of plasma discharge inside the
device ports.
The top parts of the antenna straps are protected by
limiters (see Figs. 3,a, 5) since the plasma column crosses
them in кφ=0.32 magnetic configuration. The limiters are
installed on both sides of the antenna.
U-3M and U-2M experiments shown that plasma
discharge causes an accumulation of metal impurities (Fe
and Cr) [16] that are supplied into the discharge by the
RF antennas surfaces and vacuum chamber walls. So, to
decrease the heavy impurities flow into plasma, the
antenna and the antenna limiters are covered by the
titanium nitride (TiN) film which is more resistant against
arcing and sputtering. The spectroscopic measurements in
experiments with titanium nitride covered antennas
shown that titanium influx is 50...70 times less than iron
and chromium influx from antennas without coating [17].
The main elements of the two-strap antenna and
limiters are covered with titanium nitride coating. The
TiN coating was plated in the way of vacuum arc titan
plasma condensation in high purity (99.99 %) nitrogen
atmosphere in the «Bulat-TNP4» device [18]. The
evaporated material was titanium BT1-0. The antenna
was installed on a rotary table in the range of two
vacuum arc plasma sources. The pressure was 1∙10-2 Pa
and a rotary table was under negative 1000 V potential,
the plasma sources were turned to the pulsing regime,
the antenna surface was cleaned for 5 min by titanium
ions bombardment. Then negative potential was set to
200 V, plasma sources worked in a stationary regime
and the antenna surface was plated with a titanium layer
for 5 min. Then nitrogen was added into the chamber
and its pressure was set at 2∙10-1 Pa. TiN was plated
during 20 min. The resulting coating was 3...4 μm deep.
The two-strap antenna was connected to RF complex
Kaskad-1. The RF power is transmitted from generators to
antennas through feeders. They use coaxial radiofrequency
cable RK-50-11-13. The cable is coupled with the
generator and the load feeder of length 100 m and has the
efficiency of η = 0.9...0.75 in the range of working
frequencies f = 2...14 MHz. The antenna is coupled to the
feeders via a parallel LC circuit (see Fig. 3,b), created by
the antenna inductance La and the attached capacitor С (for
dipole phasing). Such a circuit is tuned in resonance with
the frequency of the generator anode circuit. When the
resonance condition occurs, the current increases in the
antenna circuit and the radiated power becomes higher.
Also, the reactivity added by plasma is compensated in the
antenna circuit and the active plasma resistance Rp is
transformed into the value equivalent to the surge
impedance of the feeder line ρf= 25...50 Ω. So the two
circuit system is formed by the generator and antenna
circuits tuned at the same frequency. The matching device
allows one to operate in the wide range of the antenna
loading resistance values.
Fig. 2. Two-strap antenna:
Antenna model (a) and photo assembled with feed-
troughs (b). 1 – straps; 2 – fluoroplastic isolators;
3 – elements of RF feed-troughs
Fig. 3. Photo of the antenna inside the U-2M device (a)
and the antenna unit electric scheme (b): 1 – straps;
2 – limiters from both sides of antenna;
3 – fluoroplastic isolator covered with a quartz tube
Fig. 4. Position of the two-strap antenna relative to the
last closed magnetic surface: 1 – strap;
2 – last closed magnetic surface
Fig. 5. Two-strap RF input leads inside device port (3)
and limiters (2) installed from both sides of the
antenna (1)
12 ISSN 1562-6016. ВАНТ. 2020. №6(130)
3. EXPERIMENTAL DETAILS
The first run of the two-strap antenna was performed
during the U-2M vacuum chamber conditioning regime
in a weak magnetic field. This regime is described in
Refs. [6, 9-11]. The frame [7] and two-strap unshielded
antennas were used for wall conditioning. Both antennas
are situated at the outer side of the plasma column: the
frame antenna is in Z2 cross-section between 1st and 2nd
toroidal magnetic coils (see Fig. 1), the two-strap
antenna is in R1 cross-section (see Fig. 1). Two of the
frame antenna conductors are oriented along the
magnetic field and excite the slow wave. Longitudinal
currents in the two-strap antenna are small and flow far
from the plasma edge. So, weak slow wave excitation is
expected.
The frame antenna is connected to the K2
RF generator. The generator frequency is 5.5 MHz,
anode voltage UK2= 4 kV, input antenna RF power is up
to ≈ 50 kW. The two-strap antenna is connected to RF
generator K1 with a frequency of 5 MHz. K1 anode
voltage is UK1=6 kV, antenna input RF power is up to
≈70 kW.
Hydrogen as the working gas is used at the pressure
range from 3∙10-3 to 2∙10-2 Pa. The B0≈ 0.01 T magnetic
filed is created by helical, poloidal, and toroidal coils
(see Fig. 1) in кφ=0.32 magnetic configuration.
The time dependence of the electron linear density is
measured with a microwave interferometer (working
frequency is 140 GHz) in R cross-section (see Fig. 1)
[19, 20].
The spectral lines intensity time profile is registered
with monochromator-spectrometer SOLAR TII (SOL
instruments Ltd.) model MS7501i (Cherny–Turner
optical scheme) with photomultiplier in P1 cross-section
(see Fig. 1).
4. EXPERIMENTAL RESULTS AND
DISCUSSION
The tuning of all systems was done to find optimal
scenarios for RF-system functioning depending on
neutral gas pressure before the first experiments. Also,
the tuning aim is to find optimal working conditions for
the two-strap antenna for the vacuum chamber inner
surfaces conditioning scenario in a weak magnetic field.
Such a Used wall conditioning method allows one to
employ the same antennas and RF generators both for
working regime plasma creation and heating without
frequency change for the antenna and generator circuits
during conditioning regime. The wave propagation and
damping in weak magnetic fields are discussed in the
paper [9].
The current scenario with two antennas is similar to
the U-3M [9] and U-2M regime. The scenario
includesthat the frame antenna produces plasma, and the
fast wave antenna (e.g. three-half-turn antenna)
increases plasma density. The scenario of the pulse RF
wall conditioning is the following: the first frame
antenna pulse, then the simultaneous operation of two
antennas (frame and two-strap); and finally independent
two-strap antenna operation. The full pulse duration of
the RF discharge is 40 ms and the repetition rate is
5 pulse per second.
Fig. 6. Dependence of average plasma density and ОII
(441.5 nm) and Hα spectral line in time (p=0.01 Pa)
The average plasma density and spectral lines time
evolution is presented in Fig. 6. The frame antenna
starts at 10th ms and the two-strap antenna – at 15th ms.
The frame antenna (K2 generator) works independently
at the time interval 10...15th ms, creates plasma density
up to (1...3)∙1011 cm-3and demonstrates a small neutral
gas breakdown time (up to 3 ms). The simultaneous
antenna operation (generators K1 and K2) during
15...20 ms increases plasma density up to ne≈1∙1012 сm-3.
The two-strap antenna (generator K1) independently
sustains plasma density (1...4)∙1011 cm-3 for 20...25 ms
after K2 frame antenna turn off Fig. 6 shows average
plasma density and ОII,Hα lines emission during the
simultaneous antennas work. Moreover, the presence of
these oscillations or their absence (Fig. 7) depends on
the discharge parameters: gas pressure, RF frequency
and power. And it requires further research. Note that
the low-frequency oscillations in RF discharges
observed in the U-2M were previously considered in
more detail in [21].
Fig. 7 shows ОII and Hα average line emission
intensity dependence on H2 pressure. The low spectral
lines intensity is observed during the frame antenna
work. The line intensity Hα and ОII lines intensity
increases several times during simultaneous operation of
two antennas comparing to the frame antenna operation.
The change of the line intensity during operation of the
frame antenna and two antennas correlates with the
average plasma density, i.e. with increasing density, an
intensity increase is observed. The independent two-
strap antenna work shows less, equal or higher emission
intensity comparing to two antennas work depending on
working gas pressure.
ISSN 1562-6016. ВАНТ. 2020. №6(130) 13
Fig. 7. Dependence of ОII (441.5 nm) and Hα spectral
lines from time. (p=0.018 Pa)
Fig. 8. Dependence of the emission intensity of the ОII
(a) и Hα (b) lines on the H2 pressure. Black square –
frame antenna (generator K2); black circle – two-strap
(generators K2 and K1); blue triangle – two-strap
antenna (generator K1)
The lines emission intensities considerably decrease
at a pressure higher than 9∙10-3 Pa during both antennas
and two-strap antenna work (Fig. 8). The later regime
shows higher lines of emission intensity.
The obtained data shows that the two-strap antenna
can be used for vacuum chamber inner surfaces
conditioning regime in a weak magnetic field, both
independently and with pre-ionization. The two-strap
antenna in fact plays the role of three-half-turn antenna
used earlier. the further experiments show [12] that the
two-strap antenna can create plasma ne≈1∙1012 cm-3 in a
weak magnetic field (0.01...0.07 T) without initial
plasma created with the frame antenna. So the two-strap
antenna can be used together with the frame antenna
and independently.
CONCLUSIONS
The multifunctional unshielded two-strap antenna
with four independent inputs is developed and
implemented in U-2M.
The two-strap antenna operation is investigated in
the vacuum chamber inner surfaces conditioning regime
in a weak magnetic field in hydrogen atmosphere. The
antenna matching device is tuned to optimum efficiency
at plasma load conditions.
The joint operation of the two antennas, frame and
two-strap, showes the average plasma density increase
up to ne≈1∙1012 cm-3.
The RF discharge plasma can be sustained with
only two-strap antenna during the whole impulse while
the frame antenna is switched off.
ACKNOWLEDGEMENTS
This work has been carried out within the
framework of the EUROfusion Consortium and has
received funding from the Euratom research and
training programme 2014-2018 and 2019-2020 under
Grant Agreement № 633053. The views and opinions
expressed herein do not necessarily reflect those of the
European Commission.
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Article received 15.10.2020
ДВУХПОЛУВИТКОВАЯ АНТЕННА СТЕЛЛАРАТОРА УРАГАН-2М
А.В. Лозин, Ю.В. Ковтун, В.Е. Моисеенко, С.М. Мазниченко, М.М. Козуля, В.Б. Коровин,
А.Н. Шаповал, Е.Д. Крамской, Р.O. Павличенко, Н.В. Заманов, М.М. Махов, А.Ю. Красюк, Е.В. Сюсько,
А.И. Тимошенко, В.М. Листопад, T. Wauters, Ye. Kazakov, J. Ongena
Введена в эксплуатацию на Урагане-2М многофункциональная неэкранированная двухполувитковая
антенна. Отработана возможность работы двухполувитковой антенны в режиме чистки внутренних
поверхностей вакуумной камеры в малом магнитном поле Плазма создавалась и поддерживалась с
плотностью ne ~ (0,2...0,95)∙1012 см-3. При рабочей частоте f0 ~5 МГц ВЧ-плазма создавалась в стационарном
магнитном поле B0≈ 0,01 Tл при давлении водорода 3∙10-3...3∙10-2 Па.
ДВОНАПІВВИТКОВА АНТЕНА СТЕЛАРАТОРА УРАГАН-2М
О.В. Лозін, Ю.В. Ковтун, В.Є. Моісеєнко, С.М. Мазніченко, М.М. Козуля, В.Б. Коровін, А.М. Шаповал,
Є.Д. Крамський, Р.О. Павличенко, М.В. Заманов, М.М. Махов, А.Ю. Красюк, Є.В. Сюсько,
О.І. Тимошенко, В.М. Листопад, T. Wauters, Ye. Kazakov, J. Ongena
Введена в експлуатацію на Урагані-2М багатофункціональна неекранована двонапіввиткова антена.
Відпрацьована можливість роботи двонапіввиткової антени в режимі чистки внутрішніх поверхонь
вакуумної камери в слабкому магнітному полі. Плазма створювалась і підтримувалась густиною
ne ~ (0,2...0,95)∙1012 см-3. За робочої частоти f0 ~5 МГц ВЧ плазма створювалась у стаціонарному магнітному
полі B0≈ 0,01 Tл за тиску водню 3∙10-3...3∙10-2 Па.
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