MICROTHERMOPHOTOVOLTAICS POWER SYSTEM FOR PORTABLE MEMS DEVICES

Abstract A novel concept of microthermophotovoltaics (MTPV) systems is proposed for powering MEMS devices. The system uses hydrogen or hydrocarbon as fuel and does not involve any moving parts. Its fabrication and assembly are relatively simple. In this article, energy conversion efficiencies of a GaSb MTPV system incorporating broadband SiC and selective emitter material were first analyzed. Numerical and experimental studies on microcombustion processes in the MTPV system were carried out. The results show that uniform temperature distribution above 1000 K along the wall of microcylindrical combustors with a unique backward-facing step can be achieved. Finally, a prototype MTPV power system using SiC as the material for combustor and emitter, and a hexagonal GaSb cell array for energy conversion, was fabricated and tested. Electric power output ranging from 0.07 W to 0.74 W was measured. The potentials and further approaches of MTPV system were discussed. It is believed that MTPV would be a very attractive and competitive system among other power MEMS developments.

[1]  L. M. Fraas,et al.  Theoretical study of GaSb PV cells efficiency as a function of temperature , 1995 .

[2]  G. Gauba,et al.  Combustors for micro-gas turbine engines , 1998 .

[3]  Robert J. Kee,et al.  A model of elementary chemistry and fluid mechanics in the combustion of hydrogen on platinum surfaces , 1994 .

[4]  D. Liepmann,et al.  Microscale Combustion Research for Applications to MEMS Rotary IC Engine , 2001 .

[5]  Timothy J. Coutts,et al.  An overview of thermophotovoltaic generation of electricity , 1999 .

[6]  Sejin Kwon,et al.  Heat transfer and quenching analysis of combustion in a micro combustion vessel , 2002 .

[7]  Jeffrey H. Lang,et al.  MICRO-HEAT ENGINES, GAS TURBINES, AND ROCKET ENGINES -THE MIT MICROENGINE PROJECT- , 1997 .

[8]  P. Ronney,et al.  Combustion in microscale heat-recirculating burners , 2001 .

[9]  A. Carlos Fernandez-Pello,et al.  Micropower generation using combustion: Issues and approaches , 2002 .

[10]  A. Fernandez-Pello.  Micropower generation using combustion: Issues and approaches , 2002 .

[11]  Fatih Dogan,et al.  A Highly Efficient NiO-Doped MgO Matched Emitter for Thermophotovoltaic Energy Conversion , 2001 .

[12]  M. Kaviany,et al.  Nonequilibrium in the transport of heat and reactants in combustion in porous media , 2001 .

[13]  Yoshiaki Kanamori,et al.  High-temperature resistive surface grating for spectral control of thermal radiation , 2003 .

[14]  James G. Fleming,et al.  Photonic band gap effect in layer-by-layer metallic photonic crystals , 2003 .

[15]  Wenming Yang,et al.  Combustion in micro-cylindrical combustors with and without a backward facing step , 2002 .

[16]  Mitchell D. Smooke,et al.  The influence of surface chemistry on the development of minor species profiles in the premixed boundary layer combustion of an H2/air mixture , 1991 .