Preliminary demonstration of power beaming with non-coherent laser diode arrays

Abstract

Abstract. A preliminary demonstration of free-space electric power transmission has been conducted using non-coherent laser diode arrays as the transmitter and standard silicon photovoltaic cell arrays as the receiver. The transmitter assembly used a high-power-density array of infrared laser diode bars, water cooled via integrated microchannel heat sinks and focused by cylindrical microlenses. The diode array composite beam was refocused by a parabolic mirror over a 10 meter path, and received on a -1.5 x 25 cm panel of thinned single crystal high efficiency silicon solar cells. The maximum cell output obtained was several watts, and the cell output was used to drive a small motor. Due to operating constraints and unexpected effects, particularly the high nonuniformity of the output beam, both the distance and total received power in this demonstration were modest. However, the existing transmitter is capable of supplying several hundred watts of light output, with a projected received electric power in excess of 200 watts. The source radiance is approximately 5 x lo9 W/m'-steradian. With the existing 20 cm aperture, useful power transmission over ranges to -100 meters should be achievable with a DC to DC efficiency of greater than 10%. Non-coherent sources of this type are readily scalable to powers of tens of kilowatts, and with larger apertures can be used directly for power transmission up to several kilometers. Future non-coherent diode laser sources may be suitable for power transmission over hundreds of kilometers. Also, the experience gained with non-coherent arrays will be directly applicable to power beaming systems using coherent diode arrays or other array-type laser sources.

A Modular, High‐Fidelity Tool to Model the Utility of Fractionated Space Systems

“…The Wireless Power Transfer module optimized among several technologies including laser, microwave, solar concentrators and magnetic resonance 12,13,14,15,16,17,18,19,20,21,22,23,24,25 . The technology selection was based on the distance between spacecraft in a cluster, pointing requirements, cluster geometry, end-to-end efficiency of a particular technology and power, weight and size required.…”

Residual stress analysis of thin film photovoltaic cells subjected to massive micro-particle impact

“…Thin lm photovoltaic (PV) cell, which is capable of effectively converting solar energy into electrical energy, is one of the most signicant subjects in semiconductor technologies. [1][2][3][4][5][6] The monolithic triple junction cells (GaInP/GaInAs/Ge) are preferred in many elds like aircras and space satellites 7,8 for their high efficiency up to 30% air mass zero (AM0). [9][10][11][12][13][14][15] However, the mechanical stress and fracture of the multilayer PV cells introduced during manufacture and its service process play crucial roles in light-electricity conversion performances and their lifespan.…”