Hall Thrusters
Historical Overview
Mariano Andrenucci
Professor, Department of Aerospace Engineering, University of Pisa, Italy
Chairman and CEO, Alta S.p.A, Via A. Gherardesca 5, 56121 Ospedaletto, Pisa, Italy
e-mail: m.andrenucci@alta-space.com
Advanced Course
”Electric Propulsion Concepts and Systems”
ESA/ESTEC, Noordwijk, September 15-19, 2008
Hall Thrusters - Historical Overview
Early Hall Thruster Studies in the USA
In the early sixties the Hall ion
accelerator was investigated at
Lewis and Langley Research
Centers, AVCO/Everett, EOS,
United Aircraft, and Curtis Wright.
All of the devices were annular in
geometry in order to produce a
radial magnetic field throughout
the acceleration region with the
electric field applied along the
axis.
There
were
some
differences in the methods used
to preionize the flowing gas and
in the power level of operation.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 2
Hall Thrusters - Historical Overview
Early Hall Thruster Studies in the USA
One serious attempt to design
a
competitive
Hall
ion
accelerator in which the losses
were minimized was done with
an experimental study by
United
Aircraft.
The
accelerator
was
originally
designed to operate with
surface contact ionization;
however, it was found that
with
cesium
essentially
complete ionization could be
obtained near the anode by
electron bombardment.
Hall thruster research was completely abandoned in the USA in the late ’60s
in favor of other concepts.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 3
Hall Thrusters - Historical Overview
Hall Effect Thrusters
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At the beginning of the 1990s access to
the EP technology heritage of the
former Soviet Union was opened to the
western countries. This triggered a real
revolution in the EP world.
Despite initial skepticism, the HET
technology developed by the Russians
proved exquisitely suited for a variety of
space applications
Exempt from dissipative phenomena and
instabilities characterizing MPD thrusters
Higher thrust densities, easier scalability
at comparable efficiencies with respect
to Ion thrusters
How had this been achieved?
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 4
Hall Thrusters - Historical Overview
1961 : the Birth of the TAL
On the basis of research activities carried out in the late 1950s A.Zharinov proposed the
TAL scheme, obtaining the USSR “Invention Author Certificate” #24371 ( priority date
23.12.1961).
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 5
Hall Thrusters - Historical Overview
1967 : the Double Stage TAL
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Zharinov ideas were not supported by
IAE management, and in 1962 he left to
TsNIIMash.
•
In 1967 the first powerful double stage
TAL model was successfully operated.
Later on, performance levels of interest
for space operations were achieved for
such TAL models
•
TsNIIMASh shared its activity on TAL
with the Rockets and Space Corporation
Energia and with Bauman High Tech
School (BHTSc), Kharkov Aviation
Institute (KhAI) and Dnepropetrovsk
State University(DSU).
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 6
Hall Thrusters - Historical Overview
1970s : the Single Stage TAL
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At the end of the 1970s, under the
guidance of TsNIIMASh scientist
E.Lyapin, a low-power single stage
TAL model Isp lower than 3000 s
was developed.
The specific features of the single
stage TAL is the usage of a deep
hollow anode and low magnetic
induction inside the accelerating
channel (0.01-0.03Tesla) very close
to the typical level realized earlier in
SPTs.
Study of this thruster’s operation
showed that the discharge deeply
penetrates into the anode cavity and
that ~90% of the propellant flow
ionization takes place within the
cavity.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 7
Hall Thrusters - Historical Overview
1965 : Morozov and the Thermalized Potential
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Morozov did not like TAL concept
His main ideas were:
- the creation of the electric field within an
extended plasma volume with the help of the
magnetic field
- use the magnetic field lines for ion flow
focusing during acceleration
•
To obtain the ion flow focusing it was
necessary to have a relatively low electron
temperature. This implied the use of a
dielectric discharge chamber whose walls
could “cool” the electron gas with a high
secondary electron emission. In 1965
Morozov had published a paper describing
the principle of such focusing and the
equation for the plasma potential distribution
along the magnetic field line (the so-called
“thermalized” potential) which was the base
for his ideas on the ions focusing.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 8
Hall Thrusters - Historical Overview
1964 : the E-accelerator
By 1964 the team under Morozov’s guidance, including Yu. Esipchuk,
Yu. Sharov and some others from IAE laboratory headed by German
Shepkin had created the 1st so-called E-accelerator, which was
preliminarly characterized in 1964.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 9
Hall Thrusters - Historical Overview
1968 : Towards the First SPT Flight Test
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In 1968 the State Committee on Atomic Energy decided to carry out a flight test of
an SPT on board the Meteor satellite
This idea had been proposed by Morozov and supported by the academicians Lev
Artsimovich, head of the IAE Plasma Research Division, Anatoly Alexandrov, IAE
president and Andronik Iosiphian, president of the All-union Institute of
Electromechnics (VNIIEM) and chief designer of the Meteor type satellites
It was decided also that IAE would supervise the test, that the future Design Bureau
Fakel would develop the experimental propulsion system, the Design Bureau Zarya
would develop the PPU, VNIIEM would be responsible for the integration of the
propulsion system and would carry out the test with attendance of all others.
It was also decided to involve in the SPT studies the Moscow Aviation Instutute
(MAI) and Central Institute of the Aviation Motor Building
During 1969-1970 the mock-up of the experimental propulsion system (EPS) was
developed, manufactured, tested at IAE and transferred to FDB Fakel.
During 1970-1971 the EPS flight version was developed, manufactured by FDB Fakel
and DB Zarya, and tested at FDB Fakel with attendance of IAE, DB Zarya
representatives. Then it was transferred to VNIIEM and integrated
In December 1971 the Meteor satellite with SPT was launched and in 1972 the EPS
was tested in flight, operating for about 200hours .
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 10
Hall Thrusters - Historical Overview
1971 : the First SPT Flight Test
The mock-up developed at IAE in 1969 by Yu.Sharov(left side) and the first SPT
flown on the Meteor Satellite (right side) developed at Fakel by V.Bryzgalin et al.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 11
Hall Thrusters - Historical Overview
1972 - 1974 : Continuing Research Activities
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In a series of experiments carried out at MAI in 1972-1974, V. Kim and A.
Bishaev were able to obtain local plasma parameters distributions inside the
accelerating Channel.
The sputtering yield of ceramics under bombardment by the accelerated ions
generated by an SP-like plasma source was determined at MAI by a team of
scientist led by I. Shkarban
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 12
Hall Thrusters - Historical Overview
1974 : Second Flight Test
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During 1972-1974 the propulsion system functional scheme and propellant
storing and management units designs were also improved by the Fakel team
under management of the Fakel chief designer R.Snarsky and leadership of the
principal designer K.Kozubsky; the same was done for the power processing
unit by the leading designer of the first PPU’s, L.Novoselov and others at SPhTI.
As a result of such activities, the second SPT flight test Eol-2 was made in 1974
(over 600 hour s) on board of Meteor type satellite by VNIIEM and others
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 13
Hall Thrusters - Historical Overview
Further steps of the SPT development
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During 1969-1972 by IAE experts V.Mikhailichenko and E.Petrov had discovered
that SPT thrust efficiency could be significantly improved by creating the
magnetic field with great gradient in the direction from anode to the
accelerating channel exit. This was in correspondence with theoretical analysis
of the accelerated ion flow stability in the ExB fields made by A.Morozov
At the same time the cathode design which prototype was developed at IAE was
significantly improved at Fakel by B.Arkhipov and others.
The life time tests of the first flown SPT models were made at Fakel showing
that one of the main these thrusters elements wearing processes is the
discharge chamber wall erosion. It was found also that erosion rate is reduced in
time and this is the opportunity to get large enough SPT life time (Yu.Kondakov
from Fakel had derived the semiempirical law for this erosion rate variation in
time).
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 14
Hall Thrusters - Historical Overview
1974 : the Magnetic Screens
•
Another important step was the
development of a magnetic field
topology ensuring the highest
thrust efficiency, but under
increased discharge chamber
wall thickness to increase
thruster life time.
•
This was achieved for the first
time in 1973-1974 by V. Kim and
A. Bishaev by means of the
magnetic shunts (or magnetic
screens). The first laboratory
models with magnetic screens
surrounding
the
discharge
chamber were developed and
tested at MAI.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 15
Hall Thrusters - Historical Overview
1978 : the SPT-100
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The next important step was the
development of a thruster design
featuring a very large increase in life
time capability (thruster with “shifted
accelerating layer”).
•
This idea was first proposed and
tested at Fakel by V. Kozlov and was
then more carefully studied and
implemented
in
the
SPT-100
laboratory model by V. Kozlov (as PhD
student) and V. Kim at MAI during
1975-1978
•
The SPT-100 lab model was fully
tested at MAI and IAE and through an
accelerated test methodology it was
shown that thruster lifetime could
exceed 5000 hours
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 16
Hall Thrusters - Historical Overview
Preparing for Success
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Before 1980, a large number of thrusters
of different sizes and schemes had been
developed and tested at IAE, MAI and
Fakel
At the top of the range, the powerful
SPT-290 model for primary missions was
developed at Fakel under leadership of V.
Murashko.
This model was able to
operate with high efficiency at powers
levels up to 35kW and specific impulse
values over 3000s.
The outstanding success of the SPT
concept, technology and science was
achieved through the combined effort of
IAE, Fakel, MAI, TsIAM, MIREA, MSU,
KhAI, BHTSc and others.
ESA/ESTEC, Noordwijk,
September 15-19, 2008
Advanced Course: Electric Propulsion Concepts and Systems
M. Andrenucci
Slide 17