In-Space Propulsion High Voltage Hall Accelerator Development Project Overview

Abstract

NASA's Science Mission Directorate In-Space Propulsion Technology Project is funding the development of a high specific impulse long life Hall thruster. The goal of the high voltage Hall accelerator (HiVHAc) project is to develop a flight-like, engineering model (EM) Hall thruster that can meet future NASA science mission requirements. These requirements are met by a thruster that operates over an input power range from 0.3 to 3.5 kW, attains specific impulses from 1,000 to 2,700 seconds, and processes at least 300 kg of xenon propellant at full power. To demonstrate the HiVHAc project goal, two laboratory thrusters have been built and tested. The latest laboratory thruster, the NASA-103M.XL, incorporated a life-extending discharge channel replacement innovation and has been operated for approximately 5,000 hours at a discharge voltage of 700 volts. In 2007, NASA Glenn Research Center teamed with Aerojet to design and manufacture a flight-like HiVHAc EM thruster which incorporated this life-extending channel replacement innovation. The EM thruster was designed to withstand the structural and thermal loads encountered during NASA science missions and to attain performance and lifetime levels consistent with NASA missions. Aerojet and NASA Glenn Research Center have completed the EM thruster design, structural and thermal analysis, fabrication of thruster components, and have assembled and extensively tested one EMl thruster. Performance and thermal characterization of the engineering model thruster has been performed for discharge power levels up to 3.5 kW. The results indicate discharge efficiencies up to of 63% and discharge specific impulse up to 2,930 seconds. In addition to the thruster development, the HiVHAc project is leveraging power processing unit and xenon flow system developments sponsored by other projects but that can apply directly to a HiVHAc system. The goal is to advance the technology readiness level of a HiVHAc propulsion system to 6. * Aerospace Engineer, Propulsion and Propellants Branch, 21000 Brookpark Rd, Associate Fellow AIAA. and the development of long life high voltage Hall accelerator (HiVHAc) as a lower cost electric propulsion alternative for future cost constrained missions.

Design of a Laboratory Hall Thruster with Magnetically Shielded Channel Walls, Phase I: Numerical Simulations

“…1 Indeed, the advanced magnetic field topologies that are being used in many state-of-the-art (SOA) Hall thrusters today have led to improvements both in performance and wear. 2,3,4,5,6 However, channel erosion has not been eliminated or reduced sufficiently to retire the risk for deep-space science missions.…”

High voltage hall accelerator propulsion system development for NASA science missions

“…Additionally, insights gained from the temperature measurements will result in a better understanding of the power deposition into the thruster's internal components at various power levels. [18,19,20] In general, the thermal characterization results confirmed that the design changes incorporated in the EDU 2 thruster alleviated the elevated inner electromagnet temperatures that were encountered during EDU 1 thruster tests. Peak inner electromagnet temperatures of approximately 480 °C were measured at 4.2 kW.…”

A Parametric Computational Study of Boron Transport in Hall Thrusters

“…The Hall thruster modeled in the present work is NASA's High-Voltage Hall Accelerator, or HiVHAc. [15][16][17][18] The HiVHAc project is jointly conducted by NASA Glenn Research Center and Aerojet Rocketdyne with the goal of producing a long-life, high-specific-impulse Hall thruster for Discovery-class missions. The current engineering development unit (EDU2), has demonstrated operation at discharge voltages up to 650 V and discharge powers in excess of 4 kW.…”