Plasma which is supplied from a supply passage (1) is accelerated with a Hall electric field (E) which is generated through interaction of electrons (e.sup.) emitted from a cathode (3), a radial direction magnetic field (Bd), and an electric field (Ex).

The present technology is directed to plasma systems and associated methods, including propulsion systems for flight vehicles. A representative system includes a plurality of coils. The coils include a first coil positioned along a force axis, a second coil positioned along the force axis and spaced apart from the first coil, and a third coil that is magnetically shielded. A controller is operatively coupled to the coils and is configured to (a) increase energy to the first coil to generate a magnetic field in a portion of the plasma adjacent to the first coil, (b) decrease energy to the first coil and increase energy to the second coil to translate the resulting superposed magnetic field through the plasma to a position adjacent the second coil, and (c) transfer energy from the second coil to the third coil and decrease energy to the second coil to reduce the magnetic field in the plasma.

A method of operating a spacecraft propulsion system comprises injecting electrons into the plasma surrounding the spacecraft prior to creating the stream of ions, and after commencing creation of the ion stream, continuing the injection of electrons in an amount sufficient to maintain the spacecraft at a positive potential. This method may be implemented in a single thruster. In spacecraft with multiple thrusters the same method may be implemented in each thruster.

Where the propulsion system comprises a plurality of thrusters, the method may comprise: operating at least one of the thrusters as a drive thruster, and operating at least one of the thrusters as an auxiliary or reserve thruster. The electron source of the at least one auxiliary thruster may be operated before creation of the ion stream to inject the electrons into the plasma surrounding the spacecraft.

The present technology is directed to plasma systems and associated methods, including propulsion systems for flight vehicles. A representative system includes a plurality of coils. The coils include a first coil positioned along a force axis, a second coil positioned along the force axis and spaced apart from the first coil, and a third coil that is magnetically shielded. A controller is operatively coupled to the coils and is configured to (a) increase energy to the first coil to generate a magnetic field in a portion of the plasma adjacent to the first coil, (b) decrease energy to the first coil and increase energy to the second coil to translate the resulting superposed magnetic field through the plasma to a position adjacent the second coil, and (c) transfer energy from the second coil to the third coil and decrease energy to the second coil to reduce the magnetic field in the plasma.

A structure for preventing an electric discharge between devices without any need for a dedicated device when mounted on an artificial satellite is provided. A charging mitigation device for reducing a potential difference between two or more physical objects includes an electric thruster (100) configured to generate plasma (PL), wherein the two or more physical objects are covered with the plasma (PL) generated from the electric thruster (100).

A plasma thruster includes extraction of a stream of positive ions. The plasma thruster includes a single ionization stage; injecting ionizable gas for said ionization stage comprising injecting a first gas and an electronegative second gas; creating an RF electric field to cause the gases to ionize in the ionization stage creating a first zone called the hot zone, in the ionization stage; the first gas being distributed in the hot first zone, the second gas being distributed in a second zone less hot than said first zone; extracting a stream of negative ions and a stream of positive ions, these being both connected to the ionization stage; and the extraction of a stream of positive ions and the extraction of a stream of negative ions, ensuring that the thruster is electrically neutral.

An Electrostatic Ion Thruster for propulsion of spacecraft, comprising an ionization chamber with a central axis, a propellent gas inlet port, an inlet, an exit and an igniter between the propellent gas inlet port and the inlet of the ionization chamber, a propellent gas source, an ion accelerator arranged at the exit of the ionization chamber opposite the propellent gas inlet port in the direction of the central axis, the ion accelerator including at least three acceleration grids spaced apart from each other in the direction of the central axis and each extending perpendicular to the central axis, an ignition circuit electrically connected to the igniter, at least three high frequency coils surrounding at least a part of the ionization chamber, a high frequency ionization power generating unit electrically connected to the high frequency coils, and a polyphase high voltage high frequency power generating unit electrically connected to the acceleration grids.

A propulsion device for vehicles, such as a spacecraft operating within a vacuum configured to ionize a fuel gas. Specifically, a soft ionization system pulls electrons from passing gas molecules directly into conductors and introduces ionized gas molecules into a static accelerating field. The ionized gas is utilized at a point of creation such that a chamber, housing, or channel to contain the ionized gas is not required.

A thruster comprising: a chamber to contain a fluid; a plurality of nozzles to exhaust neutral particles derived from the fluid in the chamber, wherein each nozzle has a converging section and the converging section includes a first electrode; a second electrode located distal to the first electrode to provide a voltage differential between the first and second electrodes sufficient to create plasma ions from the fluid and the voltage differential accelerates the plasma ions on a flow path through the converging section, and wherein at least one or more of the accelerated plasma ions are neutralised to form the neutral particles by charge exchange with other neutral particles, or by recombination with electrons, on the flow path.

A thrust producing system includes an RF ion thruster with a discharge chamber having a gas inlet and an outlet, and a coil about the discharge chamber. The system further includes an RF cathode proximate the discharge chamber outlet of the RF ion thruster for ion beam neutralization. The RF cathode includes a discharge chamber having a gas inlet and an outlet and a coil about the discharge chamber. A tank for containing iodine in solid form and a heater associated with said tank to produce iodine vapor. A feed subsystem fluidly couples the tank with the RF ion thruster discharge chamber gas inlet and with the RF cathode discharge chamber gas inlet.