Abstract: A method of protecting a turbine compressor of a gas turbine engine that is part of an integrated gasification combined-cycle power generation system that includes an air separation unit that may include the steps of: (1) extracting an amount of compressed air that is compressed by the turbine compressor; (2) supplying the extracted amount of compressed air to the air separation unit; and (3) varying the amount of compressed air extracted from the turbine compressor based upon a desired compressor pressure ratio across the turbine compressor. The method further may include the step of supplying the air separation unit with a supply of compressed air from a main air compressor. The amount of compressed air supplied to the air separation unit by the main air compressor may be varied based upon the amount of compressed air extracted from the turbine compressor.

Abstract: A method of controlling a load of a gas turbine engine that is part of an integrated gasification combined-cycle power generation system, which includes an air separation unit, that includes the steps of: (1) extracting an amount of compressed air that is compressed by a turbine compressor; (2) supplying the extracted amount of compressed air to the air separation unit; and (3) varying the amount of compressed air extracted from the turbine compressor based upon a desired load for the gas turbine engine.