The feasibility of a stretched lens concentrating solar array direct-driving an electric thruster

Abstract

As space exploration continues to be a primary focus of NASA, solar electric propulsion (SEP) becomes a forerunner in the mode of transportation to reach the moon and other planets in our solar system. The Stretched Lens Array (SLA) is a unique ultra-high-performance, ultra-light, cost-effective photovoltaic concentrator array using refractive concentrator technology. The SLA is capable of high voltage operation and sustainability in a high radiation environment and can be specifically optimized for SEP by the ability to direct-drive Hall-effect thrusters. Auburn University has performed a "direct drive" experiment using a high-voltage (600 Voc) ENTECH SunLine concentrator array powered with multijunction solar cells coupled to a Russian T-100 Hall Effect Thruster (HET). This appears to be the first time a Hall thruster has been run directly from III-V-based multi-junction solar cells and at this high voltage. This paper discusses the set-up and testing results. Testing includes the inclusion of ENTECH's Stretched Lens Array hardware in a vacuum chamber to measure plume impingement effects at various positions relative to the exhaust axis of the thruster. The goal is to define meaningful high voltage SLA concentrator array and Hall thruster demonstration tests relevant to SEP and to test SLA reliability. © 2010 American Institute of Physics.