Gas turbines in mechanical drive applications and operating methods

Patent metadata

Field	Value
Publication number	US-9876412-B2
Application number	US-201414894629-A
Country	US
Kind code	B2
Filing date	May 29, 2014
Priority date	May 31, 2013
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

A drive system for driving a load, comprising a gas turbine configured and arranged for driving the load, an electric motor/generator electrically connected to an electric power grid, a first load coupling connecting the gas turbine to the load, a second load coupling, connecting the load to the electric motor/generator. The electric motor/generator is adapted to function as a generator for converting excess mechanical power from the gas turbine into electrical power and delivering the electrical power to the electric power grid, and as a motor for supplementing driving power to the load. The drive system comprises furthermore a disconnecting device to reversibly disconnect the load from the gas turbine, so that the load can be driven only by the motor.

First claim

What is claimed is:

1. A drive system for driving a load, the drive system comprising:
a gas turbine configured and arranged for driving the load, wherein the gas turbine comprises a gas generator compressor provided with movable inlet guide vanes and configured to receive air, the movable inlet guide vanes controlled to modify an air inlet flow rate of the air depending on operating conditions of the gas turbine and the load;
an electric motor/generator electrically connected to an electric power grid;
a first load coupling connecting the gas turbine to the load; and
a second load coupling connecting the load to the electric motor/generator, wherein the electric motor/generator is adapted to function as a generator for converting excess mechanical power from the gas turbine into electrical power and delivering the electrical power to the electric power grid, and as a motor for supplementing driving power to the load,
and wherein the drive system comprises a disconnecting device to reversibly disconnect the load from the gas turbine, so that the load can be driven only by the motor/generator.

2. The drive system of claim 1 , wherein disconnection or connection made by the disconnecting device is operated manually by an operator or automatically by a motorization.

3. The drive system of claim 1 , wherein the disconnecting device comprises a clutch between the load and the gas turbine.

4. The drive system of claim 1 , wherein the disconnecting device comprises a removable coupling or a hydraulic torque converter.

5. The drive system of claim 1 , wherein the second load coupling is arranged opposite to the first load coupling with respect to the load, such that the load is arranged between the gas turbine and the electric motor/generator.

6. The drive system of claim 1 , wherein the load comprises at least one compressor.

7. The drive system of claim 6 , further comprising a direct coupling provided between the at least one compressor and the electric motor/generator; wherein the at least one compressor and the electric motor/generator have a common shaft.

8. The drive system of claim 6 , further comprising a coupling comprising a clutch provided between the at least one compressor and the electric motor/generator.

9. The drive system of claim 1 , wherein the gas turbine comprises:
a gas generator comprising a gas generator rotor; and
a power turbine including a power turbine rotor,
wherein the power turbine rotor being mechanically separated from, or not torsionally coupled to, the gas generator rotor.

10. The drive system of claim 9 , wherein the gas generator comprises the gas generator compressor, a combustion chamber, and a high-pressure turbine; wherein the gas generator rotor comprises a first rotor of the gas generator compressor and a second rotor of the high-pressure turbine, and wherein the first rotor of the gas generator compressor and the second rotor of the high-pressure turbine being mounted on a common shaft.

11. The drive system of claim 9 , wherein the power turbine comprises movable nozzle guide vanes that can be used to modify flow conditions of combustion gas entering the power turbine from the gas generator.

12. The drive system of claim 1 , further comprising a frequency converter connected between the electric motor/generator and the electric power grid, wherein the frequency converter is configured and controlled for conditioning electric frequency from the electric power grid to the electric motor/generator and from the electric motor/generator to the electric power grid.

13. The drive system of claim 1 , wherein the electric motor/generator comprises a variable-frequency drive electric motor/generator.

14. A method of operating a gas turbine system comprising a gas turbine and a load driven by the gas turbine, the method comprising:
mechanically coupling a load to the gas turbine, wherein the gas turbine comprises a gas generator compressor provided with movable inlet guide vanes and configured to receive air;
controlling the movable inlet guide vanes to modify an air inlet flow rate of the air depending upon operating conditions of the gas turbine and the load;
mechanically coupling an electric motor/generator to the load, wherein the electric motor/generator is arranged opposite to the gas turbine with respect to the load;
generating mechanical power by the gas turbine;
powering the load with the mechanical power generated by the gas turbine;
when the mechanical power generated by the gas turbine exceeds mechanical power required to drive the load:
operating the electric motor/generator in a generator mode;
transferring excess mechanical power from the gas turbine to the electric motor/generator;
converting the excess mechanical power into electric power in the electric motor/generator;

when the mechanical power generated by the gas turbine is not null and less than the mechanical power required to drive the load:
operating the electric motor/generator in a motor mode;
electrically powering the electric motor/generator;
converting the electric power into supplemental mechanical power in the electric motor/generator;
transferring the supplemental mechanical power from the electric motor/generator to the load;
driving the load with the mechanical power generated by the gas turbine and the supplemental mechanical power generated by the electric motor/generator;

when the mechanical power generated by the gas turbine is null or the gas turbine is turning off:
disconnecting the gas turbine from the load;
operating the electric motor/generator in a motor mode;
converting the electric power into mechanical power in the electric motor/generator;
transferring the mechanical power from the electric motor/generator to the load; and
driving the load with the mechanical power generated by the electric motor/generator.

15. The method of claim 14 , wherein the load comprises at least one compressor.

16. The method of claim 15 , wherein the at least one compressor compresses a gas in a pipeline.

17. A system for storing pressure energy in a pipeline for gas, the system comprising:
at least one compressor arranged in the pipeline and configured to compress a gas in the pipeline;
a gas turbine configured and arranged for driving the at least one compressor, wherein the gas turbine comprises a gas generator compressor provided with movable inlet guide vanes and configured to receive air, and wherein the movable inlet guide vanes are controlled to modify an air inlet flow rate of the air depending upon operating conditions of the gas turbine and the load;
an electric motor/generator electrically connected to an electric power grid;
a first load coupling connecting the gas turbine to the at least one compressor;
a second load coupling, connecting the at least one compressor to the electric motor/generator, wherein the electric motor/generator is configured to function as a generator for converting excess mechanical power from the gas turbine into electrical power and delivering the electrical power to the electric power grid, and as a motor for supplementing driving power to the at least one compressor; and
a disconnecting device to reversibly disconnect the at least one compressor from the gas turbine, so that the at least one compressor can be driven only by the motor/generator,
wherein the system provides a phase of disconnection of the at least one compressor from the gas turbine, and a subsequent phase of compression of the gas in the pipeline by operating the at least one compressor only by the electric motor.

Assignees

• Nuovo Pignone Srl

Inventors

• Santini Marco
• De Iaco Marco

Classifications

• F02C7/36 Primary

  Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user ({F02C3/107 - F02C3/13 and} F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H) · CPC title

• F05D2260/4023

  through a friction clutch · CPC title

• F02C3/04

  having a turbine driving a compressor (power transmission arrangements F02C7/36; control of working fluid flow F02C9/16) · CPC title

• F05D2270/061

  in particular the electrical frequency of driven generator · CPC title

• F05D2220/764

  of the alternating current (A.C.) type · CPC title