Patent ID: 7240478

Claim:
A multi-stage supercharged gas turbine system comprising: (a) a first stage comprising, i. a gas turbine that comprises a compressor, a combustor, a first expander, and a regenerator wherein said compressor supplies pressurized air to said regenerator which warms the air which then flows through said combustor which bums fuel to heat the air stream to form a hot gas stream that expands through said first expander; ii. a positive-displacement pre-compressor that supplies pressurized air to said compressor; iii. a first cooler which receives the pressurized ambient air stream from the first pre-compressor and lowers the temperature of the air stream to form a pressurized air stream which then enters the compressor, and iv. a first post-expander located downstream from said regenerator; (b) a second stage located in series with said first stage and which operates when said first stage is running wherein said second stage comprises, i. a second positive displacement pre-compressor which pressurizes an ambient air stream, ii. a second cooler which receives the pressurized ambient air stream from the second pre-compressor and lowers the temperature of the air stream to form a pressurized air stream which then enters the positive-displacement pre-compressor of the first stage and iii. a second post-expander which receives a hot gas stream from the first post-expander.