Integration Tests of the 4 kW-class High Voltage Hall Accelerator Power Processing Unit with the HiVHAc and the SPT-140 Hall Effect Thrusters

Abstract

NASA's Science Mission Directorate is sponsoring the development of a 4 kW-class Hall propulsion system for implementation in NASA science and exploration missions. The main components of the system include the High Voltage Hall Accelerator (HiVHAc), an engineering model power processing unit (PPU) developed by Colorado Power Electronics, and a xenon flow control module (XFCM) developed by VACCO Industries. NASA Glenn Research Center is performing integrated tests of the Hall thruster propulsion system. This paper presents results from integrated tests of the PPU and XFCM with the HiVHAc engineering development thruster and a SPT-140 thruster provided by Space System Loral. The results presented in this paper demonstrate thruster discharge initiation along with open-loop and closed-loop control of the discharge current with anode flow for both the HiVHAc and the SPT-140 thrusters.Integrated tests with the SPT-140 thruster indicated that the PPU was able to repeatedly initiate the thruster's discharge, achieve steady state operation, and successfully throttle the thruster between 1.5 and 4.5 kW. The measured SPT-140 performance was identical to levels reported by Space Systems Loral.

Improving the specific impulse of Hall thrusters using a wide channel design

“…In theory, the specific impulse I sp of Hall thrusters is proportional to √U d for a specific propellant; therefore, a high discharge voltage is a necessary condition for a high specific impulse. In 1996, FSUE EDB Fakel in Russia began research on high-voltage Hall thrusters; SPT-140 [9], SPT-115 [10], SPT-1 [11], and SPT-200 [10] were successively developed. They proposed a principle of proportionality between the magnetic field intensity B and √U d [12].…”

Electric Propulsion: A Key Enabling Technology for Planetary Exploration

“…The infusion of new power processing technologies can improve efficiency, reduce mass, and provide better peak power tracking (as outlined in the white paper by Carr, et al [43]). Because power processing units are expensive and time-consuming to develop, NASA should continue the development of a system with the flexibility to run multiple types of thrusters [44].…”