Gas turbine compressor inlet pressurization system and method for power augmentation

A gas turbine system in combination with a gas turbine inlet pressurization assembly comprising:

• a compressor for compressing air to produce compressed air;
• a combustor for heating said compressed air and producing hot gases;
• a gas turbine for receiving said hot gases and converting the energy thereof to work for driving said compressor, for supplying a load, and for producing hot exhaust gases;
• a working fluid supply;
• a heat exchanger for receiving said hot exhaust gases from said gas turbine for at least one of evaporating and superheating working fluid from said fluid supply to produce superheated working fluid;
• a supercharging fan operatively coupled to said compressor for augmenting air supply to said compressor;
• an apparatus for converting energy of said superheated working fluid to shaft power for driving said supercharging fan;
• and
• an assembly for cooling airflow from said supercharging fan,
• wherein said supercharging fan is a variable speed supercharging fan, and
• wherein the apparatus for driving the fan ramps the supercharging fan speed to a target fan speed determined as a function of at least one of gas turbine system power output and gas turbine shaft speed demand.

A method for augmenting the power produced by a gas turbine system of the type having a compressor for compressing air to produce compressed air, a combustor for heating said compressed air and producing hot gases, and a turbine for receiving said hot gases and converting the energy thereof to work for driving said compressor, for supplying a load, and for producing hot exhaust gases, the method comprising:

• feeding a working fluid to a heat exchanger that receives said hot exhaust gases for at least one of the evaporating and superheating said working fluid;
• providing an assembly for converting energy of said superheated working fluid into mechanical shaft horsepower;
• driving a supercharging fan with said mechanical shaft horsepower to generate an airflow, the step of driving the fan including ramping the supercharging fan speed to a target fan speed determined as a function of at least one of gas turbine system power output and gas turbine shaft speed demand;
• cooling the airflow from said supercharging fan;
• directing said cooled airflow into said compressor thereby increasing the flow of air into the inlet of the gas turbine to increase power density through said gas turbine to produce more shaft horsepower;
• and
• further comprising varying fan speed to change shaft horsepower of the gas turbine while maintaining a nominal gas turbine firing temperature.

An inlet pressurization system for augmenting power produced by a gas turbine system of the type including a compressor for compressing air to produce compressed air, a combustor for heating said compressed air and producing hot gases, and a turbine for receiving said hot gases and converting the energy thereof to work for driving said compressor, for supplying a load, and for producing hot exhaust gases, said system comprising:

• a working fluid supply;
• a heat exchanger for receiving hot exhaust gases from said gas turbine for at least one of evaporating and superheating working fluid from said fluid supply to produce superheated working fluid;
• a supercharging fan operatively coupled to said compressor for augmenting air supply to said compressor;
• an apparatus for converting energy of said superheated working fluid to shaft power for driving said supercharging fan;
• and
• an assembly to cool airflow downstream of said supercharging fan and upstream of said compressor,
• wherein said assembly for cooling air comprises a refrigeration cycle including a compressor, a condenser, and a refrigeration evaporator cooling said air, and
• wherein said refrigeration compressor is coaxial with and mounted to a common shaft of said supercharging fan for being driven by said apparatus for driving said fan.

A gas turbine system in combination with a gas turbine inlet pressurization assembly comprising:

• a compressor for compressing air to produce compressed air;
• a combustor for heating said compressed air and producing hot gases;
• a gas turbine for receiving said hot gases and converting the energy thereof to work for driving said compressor, for supplying a load, and for producing hot exhaust gases;
• a working fluid supply;
• a heat exchanger for receiving said hot exhaust gases from said gas turbine for at least one of evaporating and superheating working fluid from said fluid supply to produce superheated working fluid;
• a supercharging fan operatively coupled to said compressor for augmenting air supply to said compressor;
• an apparatus for converting energy of said superheated working fluid to shaft power for driving said supercharging fan;
• and
• an assembly for cooling airflow from said supercharging fan,
• wherein said supercharging fan is a variable speed supercharging fan, and
• wherein said assembly for cooling air comprises a refrigeration cycle including a compressor, a condenser, and a refrigeration evaporator cooling said air, and wherein said refrigeration compressor is coaxial with and mounted to a common shaft of said supercharging fan for being driven by said apparatus for driving said fan.

A method for augmenting the power produced by a gas turbine system of the type having a compressor for compressing air to produce compressed air, a combustor for heating said compressed air and producing hot gases, and a turbine for receiving said hot gases and converting the energy thereof to work for driving said compressor, for supplying a load, and for producing hot exhaust gases, the method comprising:

• feeding a working fluid to a heat exchanger that receives said hot exhaust gases for at least one of the evaporating and superheating said working fluid;
• providing an assembly for converting energy of said superheated working fluid into mechanical shaft horsepower;
• driving a supercharging fan with said mechanical shaft horsepower to generate an airflow;
• cooling the airflow from said supercharging fan;
• directing said cooled airflow into said compressor thereby increasing the flow of air into the inlet of the gas turbine to increase power density through said gas turbine to produce more shaft horsepower;
• and
• further comprising varying fan speed to change shaft horsepower of the gas turbine while maintaining a nominal gas turbine firing temperature,
• wherein said step of cooling the airflow from the supercharging fan comprises cooling the airflow using a refrigeration cycle including a compressor, a condenser, and a refrigeration evaporator and wherein said refrigeration compressor is mounted to a common shaft with said supercharging fan for being driven with said supercharging fan by said mechanical shaft horsepower.