Patent ID: 7281378

Claim:
A system for supplying compressed air to a combustion engine so as to boost power output by the combustion engine, said system comprising: a compressor having a rotary compression device positioned in a housing defining an air inlet and a compressed air outlet, wherein the air inlet is configured to supply inlet air to the rotary compression device, wherein the rotary compression device is configured to compress the inlet air and wherein the compressed air outlet is configured to allow the compressed air to exit the housing for supply to an intake of the combustion engine; a recirculation line arranged to recirculate a portion of the compressed air discharged from the compressed air outlet back to the compressor air inlet; a recirculation valve disposed in the recirculation line and operable to control rate of flow through the recirculation line, the recirculation valve being controllable via control signals; a programmed controller in communication with the recirculation valve and programmed to send control signals to the recirculation valve to open the recirculation valve so as to recirculate compressed air through the recirculation line to the compressor air inlet when the engine is operating below a threshold engine speed, and to maintain the recirculation valve closed so as to prevent recirculation when the engine is operating above said threshold engine speed; and an air cooling device connected in fluid communication with the recirculation line and operable to cool the recirculated air upstream of the compressor air inlet, wherein the cooled air from the recirculation line is combined with the inlet air upstream of the compressor air inlet, the cooled recirculated air reducing occurrence of compressor surge.