Man Portable TPV Generator System.

Abstract : An 112 Watts electrical output thermophotovoltaic generator was fabricated. The generator consists of a propane supply, an atmospheric combustion burner, an ytterbia emitter mantle, a fused silica absorption filter and twelve silicon concentrator arrays cooled by circulating water. The fuel to electric power conversion is 1-2%. To provide extra power needed for cooling, a pre-mix combustion design capable of generating 140-180 Watts of power was made. The condition for photovoltaic cooling was evaluated by measuring heat flux. The maximum heat rejection was 2.3 W/sq cm for atmospheric combustion design, and 5.5 W/sq cm for pre-mix combustion design. The heat transfer of several PV-heat sink assemblies under different air flow velocities and ambient air temperatures was calculated. The result showed that it is feasible to use a forced-air multi-channel heat sink to cool PV cell, provided that the generator has sufficient air flow velocity, blower power and operates at no higher than 40 deg C ambient air temperature. To improve the generator portability, shock absorbers were used to lessen impact force on the emitter mantle and demonstrated a six-folds increase in vertical drop distance. Filament winding process was explored for making robust emitter structures. Self-supporting emitter structures were successfully fabricated.