A BOOST-INVERTER BASED BATTERY-SUPPORTED FUELCELL SOURCED THREE-PHASE STAND-ALONE POWER SUPPLY ABSTRACT: In this project, a three-phase boost-inverter topology is used to condition a typical low output voltage fuel cell (FC) as a stand-alone power supply. The key benefits of the proposed power supply include ability to deliver both the boosting and inversion functions in a singlestage, compactness and low cost. Additionally, the power supply incorporates a battery storage unit through a bi-directional converter to support the slow dynamics of the FC and simultaneously protect the FC as it acts as a filter for the low frequency harmonics. The threephase output voltage of the boost-inverter is voltage-mode controlled and the battery unit is current-mode controlled. BLOCK DIAGRAM: Dc source Back up unit 3ph boost inverter Output Driver section Pic controller TOOLS AND SOFTWARE USED: MP LAB ORCAD/PSPICE MATLAB/SIMULINK OUTPUT: HARDWARE SIMULATION