High Speed Plasma Probe and Electronics Suite

ABSTRACT: Busek proposed to develop an instrument package for high fidelity measurements and long-term state-of-health monitoring of plasma properties from solar electric propulsion (SEP) plasma sources in test chambers and the space environment. The proposed system will include a Faraday probe, a Langmuir probe, and an ion energy analyzer. The instrument suite will be capable of periodic, time-averaged measurements as well as time-resolved capabilities to periodically evaluate plasma oscillations up to ~100 kHz. The probes together with the electronics that control them constitute a High Speed Plasma Probe and Electronics Suite (HSPPES). The probes used for ground testing would initially be discrete units that may be translated within the plasma plume to collect data throughout the thruster plume that is required to validate and calibrate thruster plasma and plume models. For ground testing, the Electronics Module (EM) will initially be rack mounted and constructed from commercial parts. For in-space applications, the EM will be repackaged as a cube targeting a 10 x 10 x 10 cm form. The probes themselves could be mounted within the cube. Individual boards and probes may be removed or added as required for different missions.; BENEFIT: The proposed system will be used to characterize plasma thruster plumes on the ground during the test and evaluation phase of development, and in-space during thruster operations. Data taken in space may be correlated with ground measurements taken with the same probes, and with predictions made by plasma simulations. This will validate spacecraft-plume simulations, enabling their use for risk reduction associated with future missions. In-space probes may also be used for state-of-health monitoring over missions which may last 15 years or longer. The proposed system may fly on an Air Force or National Security missions, also carrying a Hall effect thruster. The system would also be used in Electric Propulsion laboratories throughout the United Stated for test and evaluation. Potential applications for Hall thrusters include station-keeping, orbit raising, inclination changes, and de-orbiting.