Disclosed is a miniaturized plasma propulsion device with minimized surface area of the thruster walls exposed to the plasma and, as a result, reduced plasma-surface interactions including a set of segmented electrodes to facilitate the following improvements compared to relevant existing technologies: 1) control of the plasma flow including focusing of the plasma plume 2) increase of the thrust 2) reduction of inefficiencies associated with the electron cross field current, and 3) mitigation of low frequency oscillations. The electrodes affect all these actions when a DC or modulated voltage is applied to one or all of them with the same or different amplitudes, with the same or different frequencies or phases which are all optimized to realize the best performance through changes in the acceleration and/or ionization regions. In addition, the applied voltage to the main electrodes may also be modulated.

A heaterless hollow cathode provides electron emission current in an electric space propulsion system. A mechanical, thermal, and electromagnetic design of the cathode apparatus is presented, and a method of operation for rapid ignition and stabilization of the cathode is provided. The keeper of the cathode apparatus has a thickness change which reduces the flow of heat away from the cathode's emitter assembly. The method for heating the emitter assembly includes controlling applied voltages so that the current flowing from the emitter assembly to the keeper is maintained at a predetermined fixed value. By this method, damage to the electron emitting surfaces of the emitter assembly by electric arcing and/or by depletion of dopant materials is avoided.

A Hall-effect thruster assembly includes a plurality of magnetic sources for creating a magnetic circuit. The plurality of magnetic sources are positioned between a first end and a second, opposite end of the Hall-effect thruster. The plurality of magnetic sources define a longitudinal axis extending through the first end and the second end. The first end is configured as a discharge end. A mount assembly is coupled to the second end. The mount assembly is configured to secure the plurality of magnetic sources to a spacecraft. A magnetic element is supported by the mount assembly. The magnetic element is positioned relative to the plurality of magnetic sources by the mount assembly.

A satellite propulsion system and methods of operating the same include a first ionization stage and a second acceleration stage. The first ionization stage has a plasma source configured to produce an arc discharge and emit a preliminary plasma. The plasma source includes an external magnetic field configured to magnetize the arc discharge. The second acceleration stage has an accelerator positioned in series with the plasma source. The accelerator is configured to accelerate the preliminary plasma out through the accelerator, thereby creating an accelerated plasma flow. The application of an activation threshold voltage to the accelerator results in a surge in system performance parameters.

An ion accelerator includes: an inner magnet having a channel extending through it in an axial direction; an outer magnet extending around the inner magnet, the magnets having like polarities so as to produce a magnetic field having two locations of zero magnetic field strength. The locations are spaced apart in the axial direction; and an anode and a cathode are arranged to generate an electrical potential difference between the locations.

A Hall thruster is configured to reduce or eliminate pole erosion by electrically tying the cathode to the thruster chassis body. The electrical connection controls the ion energy hence reducing erosion at the pole. In a different configuration, the cathode is biased by a power supply, allowing further control of the ion energy and the elimination of pole erosion, thus increasing the thruster's operational lifetime.

A Hall-effect thruster assembly includes a plurality of magnetic sources for creating a magnetic circuit. The plurality of magnetic sources are positioned between a first end and a second, opposite end of the Hall-effect thruster. The plurality of magnetic sources define a longitudinal axis extending through the first end and the second end. The first end is configured as a discharge end. A mount assembly is coupled to the second end. The mount assembly is configured to secure the plurality of magnetic sources to a spacecraft. A magnetic element is supported by the mount assembly. The magnetic element is positioned relative to the plurality of magnetic sources by the mount assembly.

A magnetic pole structure for a Hall thruster is provided. The magnetic pole structure includes: multiple wide-envelope outer magnetic pole components, a magnetic bridge, a pagoda-shaped inner magnetic pole component, a top plate, and a bottom plate, where the multiple wide-envelope outer magnetic pole components are arranged on an outer edge of the Hall thruster, symmetrical about the pagoda-shaped inner magnetic pole component, and enclose a semi-open structure; the magnetic bridge is located between each of the wide-envelope outer magnetic pole components and the pagoda-shaped inner magnetic pole component; the bottom plate is attached to a bottom part of each of the wide-envelope outer magnetic pole components and a bottom part of the pagoda-shaped inner magnetic pole component; and the top plate is attached to an upper part of each of the wide-envelope outer magnetic pole components.

Methods and systems for electric propulsion are provided. An example method includes providing a magnetic shield using an accelerating channel made of a soft magnetic material; generating, by a magnetic system, a radial magnetic field in the accelerating channel to ionize a working substance, wherein the magnetic system includes a central magnetic pole, an outer annular pole, a magnetic circuit, and coils to carry an electrical current; and generating, using an outer hollow cathode and an anode-gas distributor disposed within the accelerating channel, an electrical discharge along the accelerating channel. The accelerating channel provides the magnetic shield to force the radial magnetic field to have a maximum gradient at a location of the central magnetic pole and at a location of the outer annular pole and to force ions of a working substance to pass isolators of magnetic poles, thereby decreasing erosion of the isolators.

A Hall-effect thruster assembly includes a plurality of magnetic sources for creating a magnetic circuit. The plurality of magnetic sources are positioned between a first end and a second, opposite end of the Hall-effect thruster. The plurality of magnetic sources define a longitudinal axis extending through the first end and the second end. The first end is configured as a discharge end. A mount assembly is coupled to the second end. The mount assembly is configured to secure the plurality of magnetic sources to a spacecraft. A magnetic element is supported by the mount assembly. The magnetic element is positioned relative to the plurality of magnetic sources by the mount assembly.