Space solar power generation systems have a significant impact on Electric Propulsion (EP) technology development.1,2,3 Recent advances in solar cell, deployment, and concentrator hardware have led to significant reductions in component mass, thereby decreasing power generation system specific mass. Combined with maneuvering requirements for Air Force and DoD missions of interest, propulsive requirements emerge that provide direction for technology investments. Projections for near- to mid-term propulsion capabilities are presented indicating the need for thrusters capable of processing larger amounts of power (100 – 200 kW), operating at relatively moderate specific impulse (2000 – 6000 seconds) and high efficiency (≫ 60%), and having low propulsion system mass (≪ 1 kg/kW). Two technology areas are identified and discussed in the context of the above thruster constraints. Concentric channel Hall thrusters are an extension of a mature technology, offering operation over expanded power levels and lower propulsion system specific mass at state-of-the-art (SOTA) efficiencies. Field Reverse Configuration (FRC) thrusters are a specific type of pulsed inductive accelerator that have the potential to operate up to MW power levels, at propulsion system specific masses even lower than concentric channel Hall thrusters, and on a wider range of propellants. However, FRCs are currently less mature than the Hall thruster variants. Comparisons of candidate technologies are evaluated with VASIMR, a well publicized high power EP device currently under development.

Air Force Research Laboratory high power electric propulsion technology development

A Hall effect thruster includes at least one tank of gas under high pressure, a pressure regulator module, a gas flow rate control device, an ionization channel, a cathode placed in a vicinity of an outlet from the ionization channel, an anode associated with the ionization channel, an electrical power supply unit, an electric filter, coils for creating a magnetic field around the ionization channel, and an additional electrical power supply unit for applying a pulsating voltage between the anode and the cathode

Hall-effect thruster

Dynamic Model Construction of a Space Thermionic Nuclear Reactor

In anticipation of the needs of future light-weight, low-power spacecraft, arcjet power electronics in the 100 to 400 W operating range were developed. Limited spacecraft power and thermal control capacity of these small spacecraft emphasized the need for high efficiency. Power topologies similar to those in the higher 2 kW and 5 to 30 kW power range were implemented, including a four transistor bridge switching circuit, current mode pulse-width modulated control, and an output current averaging inductor with an integral pulse generation winding. Reduction of switching transients was accomplished using a low inductance power distribution network, and no passive snubber circuits were necessary for power switch protection. Phase shift control of the power bridge was accomplished using an improved pulse width modulation to phase shift converter circuit. These features, along with conservative magnetics designs allowed power conversion efficiencies of greater than 92.5 percent to be achieved into resistive loads over the entire operating range of the converter. Electromagnetic compatibility requirements were not considered in this work, and control power for the converter was derived from AC mains. Addition of input filters and control power converters would result in an efficiency of on the order of 90 percent for a flight unit. Due to the developmental nature of arcjet systems at this power level, the exact nature of the thruster/power processor interface was not quantified. Output regulation and current ripple requirements of 1 and 20 percent respectively, as well as starting techniques, were derived from the characteristics of the 2 kW system but an open circuit voltage in excess of 175 V was specified. Arcjet integration tests were performed, resulting in successful starts and stable arcjet operation at power levels as low as 240 W with simulated hydrazine propellants.

/pdf/power-electronics-for-low-power-arcjets-4y8cbpcm6q.pdf

Power electronics for low power arcjets

The invention relates to a Hall-effect plasma thruster including: an annular discharge channel around a main axis, having an open downstream end defined between an inner wall and an outer wall; at least one cathode; a magnetic circuit for creating a magnetic field in the channel; a conduit for supplying the channel with ionisable gas; an anode; and a distributor placed in the upstream end of the channel, said distributor allowing the ionisable gas to flow into the ionisation area of the channel in a concentric manner around the main axis. The invention is characterised in that the anode acts as a distributor and the distributor comprises directional means that generate a swirling flow of gas around the main axis at the output of the anode.

Hall-effect plasma thruster

A Hall effect thruster for propelling spacecraft and satellites includes at least two acceleration channels, each of the channels has a closed end and an open end, and a plurality of flux guides adjacent each of the channels. The plurality of flux guides includes an innermost flux guide, an outermost flux guide, and at least one intermediate flux guide. Each intermediate flux guide helps provide a magnetic field to each of two adjacent acceleration channels.

Multichannel hall effect thruster

The SPACE‐R is a compact 2 tonne space reactor that can fit into the nose cone of a Delta II, Atlas Centaur or larger booster system. It is capable of producing 40 kWe for 10 years in space environments. The system is launched without radioactivity and is designed to meet all U.S. and International public safety and environmental protection objectives with minimum loading of fissionable 235U and minimum proliferation potential. The system utilizes the single cell thermionic fuel element concept which facilities full scale prelaunch thermal and electric output testing without generation of radioactivity prior to launch and obtaining a long life safe orbit. The current design is based upon technologies, materials, components, and temperatures that have been space flight proven within the U.S. SNAP reactor program, and the Soviet Topaz reactor programs.

Space‐R thermionic space nuclear power system with single cell incore thermionic fuel elements

This invention involves a Hall effect motor using an accelerator with closed drift electrons. It contains an azimuthally closed acceleration channel (1) that has an ionization zone (2) and an acceleration zone (3) for the working medium. It is enclosed by internal (6) and external (7) walls and is open at the exit. An anode (4) is located upstream at the entrance to the channel. At least one neutralizing cathode (5) is located downstream beyond the exit aperture. The motor also comprises a magnetic system consisting of peripheral external sections situated sequentially along the azimuth and a central internal section, all sections being linked by a magnetic conductor (12) and each having a source of magnetomotive force (17, 18, 19 and 20), as well as a pole (13, 14, 15, 16) located at the exit aperture. The motor's distinguishing features are electrodes (21, 22, 23) provided at the exit aperture sequentially along the azimuth, there being no less than three external sections. The distance between the walls of the channel (1) in the acceleration zone (3) increases downstream and changes along the azimuth in accordance with the location of the sources of magnetomotive force (18, 19 and 20) of the external sections. The external poles (14, 15 and 16) and the exit aperture of the external wall (7) are displaced downstream in relation to the internal pole (17) and the exit aperture of the internal wall (6), respectively. The magnitude of the displacement does not exceed one half of the distance between poles and walls, respectively. The distance between walls (6, 7) may be increased by modification of the contour of the external wall (7).

Hall effect motor

The results of calculation and design developments of a single‐cell thermionic fuel element (TFE) for the thermionic nuclear power system (NPS) ‘‘Space‐R’’ of 40 kW power are given in this paper. Calculation characteristics of the TFE: thermal, electrical, strength, life‐time and also results of preliminary tests, are discussed.

A single‐cell TFE mock‐up of the thermionic nuclear power system ‘‘Space‐R’’

An improved design of the Hall type stationary plasma thruster has been tested in 1994. The test results are presented. The test measures performance, EMI and beam divergence of two models of thrusters from the Russian Keldysh Scientific‐Research Institute of Thermal Processes. The first of these engines, T‐100 produces 80 mN thruster with power of 1.35 kWe. The other thruster, T‐160 is larger and produces 280 nM thrust with 4.5 kWe. Endurance testing of the T‐100 for 2000 hours was completed at NIITP. Post operation wear measurements indicate that the insulator life expectency will exceed the 8000 hour design life objective. Improved efficiencies of 48 to 52% were measured for the T‐100 and 58‐62% (with elevated tank pressure) for the T‐160 at specific impulse Isp of 1600 seconds and 2000 seconds respectively.

Improved Hall type thruster

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Edward J. Britt

Author Tools

Chat about Author