Flow ratio calculation device, control device provided with same, gas turbine plant provided with said control device, flow ratio calculation method, and method for controlling fuel system

Patent metadata

Field	Value
Publication number	US-2018209352-A1
Application number	US-201515325908-A
Country	US
Kind code	A1
Filing date	Jun 8, 2015
Priority date	Aug 6, 2014
Publication date	Jul 26, 2018
Grant date	—

Abstract

A flow ratio calculation device is provided with: a flow volume ratio computer that, using a predetermined relationship between a first parameter that can express a combustion state in a combustor and a flow volume ratio of fuels flowing through multiple fuel systems, finds a flow volume ratio based on the value of the first parameter; a correction value computer that finds a correction value of the flow volume ratio when the load of a gas turbine changes; a fluctuation sensor that senses fluctuations in a value correlated with the gas turbine load; and a corrector that corrects the flow volume ratio found by the flow volume ratio computer with the correction value found by the correction value computer when a fluctuation in the load correlated value is sensed by the fluctuation sensor.

First claim

1 . A flow ratio calculation device used in a gas turbine, the gas turbine including multiple fuel systems, a compressor that generates compressed air by compressing air, a combustor that generates a combustion gas by burning fuels from the multiple fuel systems in the compressed air, and a turbine driven by the combustion gas, the flow ratio calculation device calculating a flow volume ratio of the fuels flowing in the multiple fuel systems, and comprising:
a flow volume ratio computer that receives a value of a first parameter among multiple parameters capable of expressing a combustion state in the combustor, and finds the flow volume ratio based on the received value of the first parameter using a predetermined relationship between the first parameter and the flow volume ratio; a correction value computer that finds a correction value of the flow volume ratio at a time when a load of the gas turbine changes; a fluctuation sensor that senses a fluctuation in a load correlated value that is a value changing in correlation with changes in the load of the gas turbine or that is a value of the load; and a corrector that, upon a fluctuation in the load correlated value being sensed by the fluctuation sensor, corrects the flow volume ratio found by the flow volume ratio computer with the correction value found by the correction value computer.

2 . The flow ratio calculation device according to claim 1 ,
wherein the correction value computer receives a value of a second parameter, among the multiple parameters, that is different from the first parameter, and finds the correction value based on the received value of the second parameter using a predetermined relationship between the second parameter and the correction value.

3 . The flow ratio calculation device according to claim 2 ,
wherein the first parameter is an inlet temperature correlated value that is a value changing in correlation with changes in an inlet temperature of the combustion gas in the turbine or that is the inlet temperature; and the second parameter is one of an output of the gas turbine, a load percentage that is a percentage of a current load relative to a maximum load permitted by the gas turbine, a flow volume of all fuels supplied to the combustor from the multiple fuel systems, and a flow volume of air taken into the compressor.

4 . The flow ratio calculation device according to claim 2 ,
wherein the correction value computer includes an increase time correction value computer that finds a correction value based on the value of the second parameter when the load correlated value is increasing, using a predetermined increase time relationship between the second parameter and the correction value at the time when the load correlated value is increasing, and a decrease time correction value computer that finds a correction value based on the value of the second parameter when the load correlated value is decreasing, using a predetermined decrease time relationship between the second parameter and the correction value at the time when the load correlated value is decreasing; and the corrector corrects the flow volume ratio found by the flow volume ratio computer with the correction value found by the increase time correction value computer upon the fluctuation sensor sensing an increase in the load correlated value, and corrects the flow volume ratio found by the flow volume ratio computer with the correction value found by the decrease time correction value computer upon the fluctuation sensor sensing a decrease in the load correlated value.

5 . The flow ratio calculation device according to claim 1 ,
wherein the corrector includes a correction value adjuster that changes the correction value to be outputted so as to be closer to the correction value found by the correction value computer with the passage of time, and a flow volume ratio corrector that corrects the flow volume ratio found by the flow volume ratio computer with the correction value outputted from the correction value adjuster.

6 . The flow ratio calculation device according to claim 1 ,
wherein the combustor includes a pilot burner and a main burner that spray fuels; the gas turbine includes, as the multiple fuel systems, a pilot fuel system that supplies a fuel to the pilot burner and a main fuel system that supplies a fuel to the main burner; and the flow volume ratio includes a pilot fuel ratio that is a ratio of a flow volume of the fuel supplied to the combustor from the pilot fuel system relative to a total flow volume of the fuels supplied to the combustor from the multiple fuel systems.

7 . The flow ratio calculation device according to claim 2 ,
wherein the combustor includes a pilot burner and a main burner that spray fuels; the gas turbine includes, as the multiple fuel systems, a pilot fuel system that supplies a fuel to the pilot burner and a main fuel system that supplies a fuel to the main burner; the flow volume ratio includes a pilot fuel ratio that is a ratio of a flow volume of the fuel supplied to the combustor from the pilot fuel system relative to a total flow volume of the fuels supplied to the combustor from the multiple fuel systems; the correction value computer includes an increase time correction value computer that finds a correction value based on the value of the second parameter when the load correlated value is increasing, using a predetermined increase time relationship between the second parameter and the correction value at the time when the load correlated value is increasing, and a decrease time correction value computer that finds a correction value based on the value of the second parameter when the load correlated value is decreasing, using a predetermined decrease time relationship between the second parameter and the correction value at the time when the load correlated value is decreasing; the corrector corrects the flow volume ratio found by the flow volume ratio computer with the correction value found by the increase time correction value computer upon the fluctuation sensor sensing an increase in the load correlated value, and corrects the flow volume ratio found by the flow volume ratio computer with the correction value found by the decrease time correction value computer upon the fluctuation sensor sensing a decrease in the load correlated value; and the decrease time correction value computer calculates a correction value having a greater value than the correction value found by the increase time correction value computer when the value of the second parameter is the same value.

8 . The flow ratio calculation device according to claim 4 ,
wherein the combustor includes a pilot burner and a main burner that spray fuels; the gas turbine includes, as the multiple fuel systems, a pilot fuel system that supplies a fuel to the pilot burner and a main fuel system that supplies a fuel to the main burner; the flow volume ratio includes a pilot fuel ratio that is a ratio of a flow volume of the fuel supplied to the combustor from the pilot fuel system relative to a total flow volume of the fuels supplied to the combustor from the multiple fuel systems; and the correction value computer calculates the correction value so as to increase the pilot fuel ratio calculated by the flow volume ratio computer.

9 . The flow ratio calculation device according to claim 8 ,
wherein, upon the fluctuation sensor sensing a decrease in the load correlated value, the corrector corrects the pilot fuel ratio using the correction value found by the correction value computer so that the pilot fuel ratio calculated by the flow volume ratio computer increases.

10 . The flow ratio calculation device according to claim 1 ,
wherein the co

Assignees

• Mitsubishi Hitachi Power Sys

Inventors

• Endo Yoji
• NAKAGAWA Jotaro
• Ochiai Yoshiaki

Classifications

• F23R3/36

  Supply of different fuels · CPC title

• F02C9/34

  Joint control of separate flows to main and auxiliary burners · CPC title

• F23R3/286

  having fuel-air premixing devices (F23R3/30 takes precedence) · CPC title

• F02C9/263

  by means of fuel metering valves · CPC title

• F05D2260/96

  Preventing, counteracting or reducing vibration or noise · CPC title