JPH06193471A - Method of controlling regenerative gas turbine and control device therefor - Google Patents

Abstract

PURPOSE:To provide a method and a device for controlling a regenerative gas turbine device so as to prevent the inlet temperature of a turbine from excessively increasing even though the gas turbine device is frequently started and stopped. CONSTITUTION:A rotational speed N of a turbine 4 is detected so as to compute a first fuel flow rite Q with which the rotational speed is maintained at a desired value NREF, and further, a temperature T4 of exhaust gas from the gas turbine is detected so as to calculate a second fuel flow rate Q2 with which the exhaust gas temperature is maintained at a desired value TREF. Further, a third fuel flow rate Q'3 for limiting the acceleration so as to prevent the inlet temperature of the turbine from reaching a predetermined maximum temperature is calculated, and an outlet temperature T5 of a heat-exchanger 3 is detected so as to correct the third fuel flow rate. Then, the flow rate of fuel adapted to be fed into a burner 2 is controlled so as to become a value which is the lowest one of the first, second, and corrected third fuel flow rates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine control device, and more particularly to a control method and a control device for a regenerative gas turbine device.

[0002]

2. Description of the Related Art A conventional regenerative gas turbine apparatus, for example, as shown in FIG. 3, includes a compressor 1 for compressing air, a combustor 2 for combusting fuel with the compressed air, and a combustion from the combustor. The turbine 4 driven by gas and the heat exchanger 3 for heating the compressed air by the exhaust gas of the turbine 4 are provided, the turbine 4 and the compressor 1 are directly connected, and the compressor is driven by the output of the turbine. There is. Further, the shaft of the turbine 4 is connected to an external load 5 such as a generator or a pump and drives the external load 5. In addition, another turbine (not shown) may be provided separately from the turbine 4, and the shaft thereof and the external load 5 may be connected. Further, the connection between the turbine and the compressor, and the connection between the turbine and the external load may be connected via a speed reducer or a speed increaser. The exhaust gas temperature of such a turbine is
It is usually high (for example, 500 ° C. or higher). Therefore, by heating the compressed air supplied to the combustor 2 by the heat exchanger 3, the thermal efficiency of the gas turbine cycle can be increased.

[0003]

The conventional regenerative gas turbine system described above detects, for example, the rotation speed of the turbine and the exhaust gas temperature of the turbine so that the rotation speed and the exhaust gas temperature become constant in a steady state. Controlled. However, when the rotational speed of the turbine is accelerated, a large amount of fuel is supplied to the combustor, but if the amount of fuel is too large, the inlet temperature of the turbine becomes too high, which may damage the blades of the turbine. Moreover, the inlet temperature of the turbine, that is, the combustion gas temperature of combustion is as high as about 1200 ° C. in the case of a ceramic turbine, for example, and mixing is insufficient immediately after combustion and temperature variation is severe, so it is detected by a normal temperature sensor. Is difficult. Therefore, especially during acceleration, acceleration fuel limit control is generally performed to control the fuel so as to limit the maximum acceleration. However, since such a conventional regenerative gas turbine device is controlled on the basis of the steady state of the gas turbine device, the heat exchanger is not used at the time of startup or when the gas turbine device is stopped and restarted immediately. If the temperature is not in a steady state, the amount of combustion is too large even by the acceleration fuel limit control, and the turbine inlet temperature becomes excessively high, which may damage the turbine blade.

The present invention was devised to solve such problems. That is, an object of the present invention is to provide a control method and a control device for a regenerative gas turbine device in which the inlet temperature of the turbine does not become too high even when the gas turbine device is frequently started and stopped. Especially.

[0005]

According to the present invention, a compressor for compressing air, a combustor for combusting fuel with the compressed air, and a combustion gas driven from the combustor,
In a control method of a regenerative gas turbine device, which includes a turbine directly connected to a compressor and a heat exchanger that heats compressed air by exhaust gas of the turbine, the rotational speed of the turbine is detected and maintained at a desired rotational speed. To calculate the first amount of fuel for the purpose of detecting the exhaust gas temperature of the turbine, to calculate the second amount of fuel to maintain the desired exhaust gas temperature, the inlet temperature of the turbine reaches a predetermined maximum temperature. A third fuel quantity for limiting the acceleration so as not to detect and to detect the outlet air temperature of the heat exchanger and thereby correct the third fuel quantity, and then to supply fuel to the combustor. There is provided a control method for a regenerative gas turbine device, characterized in that the amount is controlled to be the smallest fuel amount among the first fuel amount, the second fuel amount, and the modified third fuel amount. Furthermore, according to the present invention, a compressor for compressing air,
Regenerative type equipped with a combustor that combusts fuel with compressed air, a turbine that is driven by combustion gas from the combustor and is directly connected to the compressor, and a heat exchanger that heats the compressed air with exhaust gas from the turbine In a control device of a gas turbine device, a rotation speed control device that detects a rotation speed of a turbine and controls a first fuel amount for maintaining a desired rotation speed, and a desired exhaust gas by detecting an exhaust gas temperature of the turbine. The exhaust gas temperature control device for controlling the second fuel amount for maintaining the temperature, the inlet air pressure of the heat exchanger, and the outlet air temperature of the heat exchanger are detected, and the inlet temperature of the turbine is a predetermined maximum temperature. An acceleration limiting device for controlling a third fuel amount for limiting acceleration so that the acceleration limiting device does not reach the acceleration limit, the acceleration limiting device calculating the third fuel amount from the inlet air pressure of the heat exchanger. A fuel computing circuit, the computed third fuel quantity consists acceleration fuel correction circuit for correcting the outlet air temperature, further, the amount of fuel supplied to said combustor,
There is provided a control device for a regenerative gas turbine device, comprising a fuel control device that controls the fuel amount to be the smallest of the first fuel amount, the second fuel amount, and the corrected third fuel amount. It

[0006]

According to the above configuration of the present invention, the outlet air temperature of the heat exchanger is detected, and the third fuel amount for limiting the acceleration is controlled so that the inlet temperature of the turbine does not reach the predetermined maximum temperature. The amount of fuel supplied to the combustor is controlled based on the calculated third fuel amount, so that the temperature of the heat exchanger is steady, such as when the gas turbine device is stopped and restarted immediately. Even when not in the state, the fuel amount can be controlled so that the inlet temperature of the turbine does not become too high.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a regenerative gas turbine device equipped with a control device according to the present invention. In this figure, the regenerative gas turbine apparatus is similar to the apparatus shown in FIG. 3 in that a compressor 1 that compresses air, a combustor 2 that combusts fuel with the compressed air, and a combustion from the combustor 2 A turbine 4 driven by gas and directly connected to the compressor 1 and a heat exchanger 3 that heats compressed air by the exhaust gas of the turbine 4 are provided. Further, the control device according to the present invention is designed so that the outlet air temperature T5 of the heat exchanger 2, that is, the combustor 2
The control device 20 detects the air inlet temperature and controls the fuel amount so as to limit the acceleration so that the temperature of the combustion gas does not reach the maximum temperature of the turbine. In the figure, 21 is a flow rate control valve for fuel, and the flow rate control valve 21 is controlled by the output of the control device 20 to control the fuel amount.

FIG. 2 is a control block diagram of the controller 20. In this figure, a control device according to the present invention detects a rotational speed N of a turbine 4 and controls a first fuel amount Q1 for maintaining a desired rotational speed NREF. An exhaust gas temperature control device 12 for detecting the exhaust gas temperature T4 and controlling a second fuel amount Q2 for maintaining the desired exhaust gas temperature TREF, and a heat exchanger 3
Inlet air pressure P2 and outlet air temperature T5 of the heat exchanger 3
And an acceleration limiting device 14 for controlling a third fuel amount for limiting the acceleration so that the inlet temperature of the turbine does not reach a predetermined maximum temperature.

The rotation speed control device 10 compares the detected rotation speed N with a desired rotation speed NREF and outputs the difference, and a desired rotation speed NREF from the output of the first comparison circuit 10a. And a first arithmetic circuit 10b for calculating and outputting a first fuel amount Q1 for obtaining The gas temperature speed control device 12 obtains the desired exhaust gas temperature TREF from the output of the second comparison circuit 12a and the second comparison circuit 12a which compares the detected exhaust gas temperature T4 with the desired exhaust gas temperature TREF and outputs the difference. And a second arithmetic circuit 12b for calculating and outputting a second fuel amount Q2 for In addition, the acceleration limiting device 14 changes from the inlet air pressure P2 of the heat exchanger 3 to the third
It comprises an acceleration fuel calculation circuit 14a for calculating the fuel amount Q3 'and an acceleration fuel correction circuit 14b for correcting the calculated third fuel amount Q3' by the outlet air temperature T5 of the heat exchanger 3. Further, a fuel control device 16 is provided for controlling the fuel quantity Q supplied to the combustor to the smallest fuel quantity of the first fuel quantity Q1, the second fuel quantity Q2, and the modified third fuel quantity Q3. . This fuel control device 16 is a low selector, and outputs a signal of the smallest fuel amount among the first fuel amount Q1, the second fuel amount Q2, and the corrected third fuel amount Q3 to the flow rate control valve 21, It is designed to control the amount of fuel in the combustor.

The control of the regenerative gas turbine device is performed as follows by the control device having the above configuration. That is, the first fuel amount for detecting the rotational speed of the turbine to maintain the desired rotational speed is calculated, and the second fuel amount for detecting the exhaust gas temperature of the turbine and maintaining the desired exhaust gas temperature is detected.
Of the fuel, and a third fuel amount for limiting the acceleration so that the turbine inlet temperature does not reach the predetermined maximum temperature, and the outlet air temperature of the heat exchanger is detected. The third fuel amount is corrected by, and then the fuel amount supplied to the combustor is controlled to be the smallest fuel amount among the first fuel amount, the second fuel amount, and the corrected third fuel amount. To do.

[0011]

According to the above-described configuration of the present invention, a third air conditioner for detecting the outlet air temperature of the heat exchanger and limiting acceleration so that the inlet temperature of the turbine does not reach a predetermined maximum temperature. Since the fuel amount is calculated and the fuel amount supplied to the combustor is controlled by the third fuel amount, as in the case of starting or when the gas turbine device is stopped and immediately restarted,
Even when the temperature of the heat exchanger is not in a steady state, the fuel amount can be controlled so that the turbine inlet temperature does not become too high. Therefore, the method and apparatus of the present invention provide a control method and a control apparatus for a regenerative gas turbine apparatus in which the inlet temperature of the turbine does not become too high even when the gas turbine apparatus frequently starts and stops. be able to.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a regenerative gas turbine device including a control device according to the present invention.

FIG. 2 is a control block diagram of a control device according to the present invention.

FIG. 3 is an overall configuration diagram of a conventional regenerative gas turbine device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Combustor 3 Heat exchanger 4 Turbine 10 Rotational speed control device 12 Exhaust gas temperature control device 14 Acceleration limiting device 14a Acceleration fuel calculation circuit 14b Acceleration fuel correction circuit 16 Fuel control device (low selector) 20 Control device 21 Flow rate control Valve N Turbine rotation speed NREF Desired rotation speed T3 Turbine inlet temperature T4 Turbine exhaust gas temperature T5 Heat exchanger outlet air temperature TREF Desired exhaust gas temperature P2 Heat exchanger inlet air pressure

Claims (2)

[Claims] 1. A compressor for compressing air, a combustor for combusting fuel with compressed air, a turbine driven by combustion gas from the combustor and directly connected to the compressor, and exhaust gas from the turbine. In a control method of a regenerative gas turbine device including a heat exchanger that heats compressed air, a first fuel amount for detecting a rotation speed of a turbine and maintaining the rotation speed at a desired value is calculated, and an exhaust gas of the turbine is calculated. A second fuel amount for detecting the temperature to maintain the desired exhaust gas temperature is calculated, and a third fuel amount for limiting acceleration so that the turbine inlet temperature does not reach a predetermined maximum temperature. Is calculated, and the outlet air temperature of the heat exchanger is detected.
The fuel amount supplied to the combustor is controlled to the smallest fuel amount among the first fuel amount, the second fuel amount, and the corrected third fuel amount. A method for controlling a regenerative gas turbine device characterized. 2. A compressor for compressing air, a combustor for combusting fuel with the compressed air, a turbine driven by combustion gas from the combustor and directly connected to the compressor, and exhaust gas from the turbine. In a control device for a regenerative gas turbine device including a heat exchanger that heats compressed air, a rotation speed control device that detects a rotation speed of a turbine and controls a first fuel amount for maintaining a desired rotation speed. An exhaust gas temperature control device that detects the exhaust gas temperature of the turbine and controls the second fuel amount for maintaining the desired exhaust gas temperature, an inlet air pressure of the heat exchanger, and an outlet air temperature of the heat exchanger. An acceleration limiting device for detecting and controlling a third amount of fuel for limiting acceleration so that the inlet temperature of the turbine does not reach a predetermined maximum temperature, the acceleration limiting device comprising an inlet of the heat exchanger. An acceleration fuel calculation circuit that calculates the third fuel amount from the air pressure, and an acceleration fuel correction circuit that corrects the calculated third fuel amount by the outlet air temperature. Further, the fuel amount supplied to the combustor. Is provided with a fuel control device that controls the fuel amount to the smallest one of the first fuel amount, the second fuel amount, and the corrected third fuel amount.