Vanguard Space Technologies (United States)

Implementing new solar panel technology is often hampered by the difficulty in obtaining flight heritage and integrating experimental technology into conventional panels. Modular solar panel technology overcomes this limitations by allowing substitution of an experimental module into a modular flight arrays using mostly conventional modules. The approach also allows the benefits of full-scale testing when test article sizes are limited, and easier repairability by allowing damaged modules to be unplugged and repaired off-line. The Modular Solar Array with Integrated Construction (MOSAIC) technology described in this paper is being flight tested on an experiment called MATRS (Modular Array Technology for Reconfigurable Spacecraft). The flight test unit includes modules with conventional space cells, as well as advanced modules incorporating 4-junction IMM cells to demonstrate the ease of ground integration and replacement of the modular approach, incorporation of experimental modules in flight, and life cycle performance.

A modular panel approach for spacecraft solar arrays is described that uses space qualified materials, including conventional high efficiency crystalline solar cells, and engineers the component designs for producibility. The module design includes a multi-cell protective transparent coverglass replacement layer, insulating substrate, interconnects, diodes and wiring. The approach allows improved environmental resistance, while simultaneously providing a design that has enough standardization that it can be transitioned to a repetitive production environment. Features built into the layers position the Cell-Interconnect (CI) assemblies, solder preforms and wiring connections, allowing a one step process for covering, stringing, laydown and wiring of the array of solar cells into series-parallel strings. The lamination approach also allows the solar cells to be mounted onto a Kapton flex-circuit layer, which, together with a multi-cell, conductively coated cover, can provide electromagnetic cleanliness needed for some missions. Samples of solar cell stack including coverglass replacement material, as well as 2- and 4-cell submodules were built and tested in LEO environments, including thermal cycling, vacuum ultraviolet and proton irradiation, which led to a flight test on MISSE-7. Data from the first year in LEO confirms the ability of the design to perform on a par with current qualified solar panels using custom designs with conventional coverglass. A standardized single string module that fits into a larger panel frame was developed with eighteen modules fabricated, assembled into three panels, and subsequently integrated into a three panel array. A simulated zero-G deployment of the 3-panel array was demonstrated, looking towards possible application to an ESPA-size spacecraft.