JPH1037763A - Intercooler switching control device of wet air gas turbine facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unstable condition of combustion of a combustor, misfire, and the like by bypassing compressed air to a bypass pipe when wet air gas turbine facility is started and stopped, and preventing over cooling of compressed air by an intercooler. SOLUTION: When a gas turbine starting command 19A is inputted to the set side S of a hold circuit 24 of a starting time switching circuit 22, the outlet temperature of a high pressure air compressor is low at an initial start, an intercooler operating signal 28 is not outputted from an AND circuit 25, and thereby, a fully opening signal 37 is outputted from a NOT circuit 36 so as to fully open a bypass valve 15. The inlet valve 16a and the outlet valve 16b of an intercooler side valve 16 are fully closed by a fully closing signal 42 from the NOT circuits 40, 41 of a stop time switching circuit 23. As a result, a wet air gas turbine facility is started in a condition in which compressed air led from a low pressure air compressor to a high pressure air compressor is bypassed to a bypass pipe, and thereby, it is possible to prevent over cooling of compressed air by the intercooler, and it is also possible to carry out combustion of a combustor stably.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intercooler switching control device for humid air gas turbine equipment.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a conventional humid air gas turbine facility. A low pressure air compressor 2, a high pressure air compressor 3, and a high pressure gas turbine 4 are mounted on the same shaft 1.
And a low-pressure gas turbine 5, and a generator 6 is connected to an end of the shaft 1.

[0003] The atmosphere is sucked into the low-pressure air compressor 2 and compressed, and the compressed air 7 compressed by the low-pressure air compressor 2 is cooled by an intercooler 8. The compressed air 7 is introduced into the high-pressure air compressor 3 and is further compressed. The compressed air 7 having a high pressure is guided to the humidification tower 9 and the volume thereof is increased by mixing the steam.

[0004] The compressed air 7 'mixed with steam in the humidification tower 9 to become humid air is introduced into a combustor 10 and burns together with a fuel 11 such as natural gas. The gas is introduced into the gas turbine 4 to drive the high-pressure gas turbine 4, and is subsequently introduced into the low-pressure gas turbine 5 to drive the low-pressure gas turbine 5, and then exhausted.

[0005] The intercooler 8 is supplied with water 13. The supplied water 13 cools the compressed air 7 guided from the low-pressure air compressor 2 to the high-pressure air compressor 3 and at the same time. The water itself is heated to become heated water 13 ′, guided to the humidification tower 9, the steam is separated and mixed with the compressed air 7, and the non-evaporated heated water 13 ′ is mixed with the water 13 to form an intercooler. A circulation back to 8 is performed.

In the humid air gas turbine equipment, the compressed air 7 compressed by the low-pressure air compressor 2 is cooled by heat exchange with water 13 by an intercooler 8 to reduce the volume, and then the high-pressure air is cooled. By compressing with the compressor 3, the compression efficiency can be increased.

[0007] Further, the volume of the compressed air 7 which has become high pressure in the high-pressure air compressor 3 is increased by mixing the steam in the humidification tower 9. The compressed air 7 ′ (humid air) whose volume has been increased by the mixing of steam as described above is burned in the combustor 10 to become a high-temperature and high-pressure gas 12. 5, the high-pressure gas turbine 4 and the low-pressure gas turbine 5 are driven with high efficiency.

In the conventional wet air gas turbine equipment shown in FIG. 4, the gas turbines 4 and 5 are started and stopped, and the gas turbines 4 and 5 are normally operated based on a gas turbine load command. In this state, the intercooler 8 is always used to cool the compressed air 7 guided from the low-pressure air compressor 2 to the high-pressure air compressor 3.

[0009]

However, as described above, when the intercooler 8 is always operated regardless of whether the gas turbines 4 and 5 are started, stopped, or in normal operation, it is particularly necessary to operate the intercooler 8 at all times. At the beginning of the operation of the gas turbines 4 and 5 in which the flow rate of the compressed air 7 is low and immediately before the stop, the compressed air 7 is supercooled by the cooling by the intercooler 8, so that the wetness guided to the combustor 10 is reduced. When the temperature of the compressed air 7 ′, which is air, is reduced, there is a problem that combustion in the combustor 10 becomes unstable, and in some cases, a fire may occur.

[0010] The present invention provides a humid air gas turbine system that prevents compressed air from being supercooled when starting and stopping a gas turbine in which the flow rate of compressed air is reduced, and stabilizes combustion in a combustor. It is an object of the present invention to provide an intercooler switching control device.

[0011]

According to the present invention, compressed air from a low-pressure air compressor is cooled by an intercooler and supplied to a high-pressure air compressor, and compressed air from the high-pressure air compressor is increased by a humidification tower. An intercooler switching control device for humid air gas turbine equipment that introduces gas into a dampening combustor and performs combustion, and sequentially introduces the combusted gas into a high-pressure gas turbine and a low-pressure gas turbine, and is compressed by a low-pressure air compressor. To the high-pressure air compressor via the intercooler, a bypass pipe provided to bypass the intercooler, a bypass valve provided in the bypass pipe, and air on the intercooler side of the bypass pipe. An intercooler valve installed in the pipe, a thermometer that detects the outlet temperature of the high-pressure air compressor, and the outlet temperature of the high-pressure air compressor when the gas turbine is started. The bypass valve open until it reaches in,
When the intercooler side valve is closed, the intercooler side valve is opened when the high-pressure air compressor outlet temperature reaches the set temperature, and the bypass valve is closed. An intercooler switching control device for humid air gas turbine equipment, comprising: a control device having a stop-time switching circuit that opens the bypass valve when the load becomes lower than the set load and switches the intercooler side valve to close. It is related.

In the present invention, when the humid air gas turbine equipment is started and stopped, the compressed air is bypassed to the bypass pipe, so that the compressed air is prevented from being supercooled by the intercooler. This prevents problems such as instability of combustion of the combustor and misfire that occurred when starting and stopping the wet gas turbine equipment.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an embodiment of the present invention applied to the conventional humid air gas turbine equipment shown in FIG. 4. In FIG. 1, the same reference numerals as those in FIG. Is represented.

As shown in FIG. 1, the intercooler 8 is bypassed to an air pipe 14 for supplying the compressed air 7 compressed by the low-pressure air compressor 2 to the high-pressure air compressor 3 via the intercooler 8. Provided a bypass pipe 14a,
A bypass valve 15 is provided in the bypass pipe 14a.

The bypass pipe 14 in the air pipe 14
An intercooler-side valve 16 is provided in the air pipe 14b on the intercooler 8 side from a. The example of FIG. 1 shows a case where the intercooler side valve 16 is configured by an inlet valve 16a provided on the inlet side of the intercooler 8 and an outlet valve 16b provided on the outlet side of the intercooler 8. In the description, a case will be described in which the inlet valve 16a and the outlet valve 16b are provided. The intercooler side valve 16 may include only one of the inlet valve 16a and the outlet valve 16b as necessary.

A thermometer 17 for detecting the temperature of the compressed air 7 is installed at the outlet of the high-pressure air compressor 3, and the outlet temperature 18 detected by the thermometer 17 and a gas turbine start command 19A, gas turbine stop command 19B,
A control device 21 that receives a gas turbine control signal 19 including a gas turbine load command 19C and the like and outputs a switching signal 20 to the bypass valve 15 and the inlet valve 16a and the outlet valve 16b that are the intercooler side valves 16 is provided. I do.

FIG. 2 shows a logic circuit of the control device 21. The logic circuit is roughly composed of a start-up switching circuit 22 and a stop-time switching circuit 23.

When the gas turbine start command 19A is issued, the start-time switching circuit 22 inputs the command 19A to the AND circuit 25 via the set side S of the hold circuit 24.

During normal operation, the temperature of the compressed air 7 cooled by the intercooler 8 shown in FIG. 1 and introduced into the high-pressure air compressor 3 is, for example, about 60 ° C. The outlet temperature is, for example, about 280 ° C., and in such a case, the outlet temperature 1 of the high-pressure air compressor 3
8 is set to, for example, 150 ° C., and the high-pressure air compressor 3 outlet temperature 18 detected by the thermometer 17 is set to the set temperature T.
Then, the signal 26 is output to the timer 27, and after a predetermined time set in the timer 27, the signal 26 is output to the AND circuit 25.

When the gas turbine start command 19A from the hold circuit 24 and the signal 26 from the timer 27 are input to the AND circuit 25 together, an intercooler operation signal 28 is output from the AND circuit 25 to the AND circuit 29. It has become so.

When a gas turbine stop command 19B is issued to the reset side R of the hold circuit 24, the command 19B is input as a reset signal.

When the start-up switching circuit 22 has a signal 30 for fully opening the inlet valve 16a and a signal 31 for fully opening the outlet valve 16b, the intercooler side valve 16, Full open signal 3
And an AND circuit 33 for outputting the intercooler operation signal 28 and the intercooler side valve fully open signal 3
When 2 are input to the AND circuit 29 together, the fully closed signal 35 is output to the bypass valve 15 via the set side S of the hold circuit 34. A reset signal 49 from an OR circuit 47 to be described later is input to a reset side R of the hold circuit 34.

Further, a fully closed signal 35 output from the hold circuit 34 is input to a knot circuit 36. When the fully closed signal 35 is input, no signal is output, and the fully closed signal 35 is output. Bypass valve 1 when not input
5, a full open signal 37 is output.

The stop-time switching circuit 23 has a hold circuit 38 for inputting an intercooler operation signal 28 from the AND circuit 25 of the start-time switching circuit 22. The intercooler operation signal 28 is input to the hold circuit 38. Then, the fully open signal 39 is output to each of the inlet valve 16a and the outlet valve 16b of the intercooler side valve 16 via the set side S.

A fully open signal 39 output from the hold circuit 38 is input to knot circuits 40 and 41, respectively. The knot circuits 40 and 41 operate when the intercooler operation signal 28 is input. A signal is not output, and when the intercooler operation signal 28 is not input, a fully closed signal 42 is output to the inlet valve 16a and the outlet valve 16b.

Furthermore, when the gas turbine stop command 19B is issued, the stop-time switching circuit 23 is configured to input the command 19B to the AND circuit 44 via the set side S of the hold circuit 43.

When the maximum load of the humid air gas turbine equipment is, for example, 250 MWD, a set load P of, for example, 40 MWD is set in the load command 19C of the gas turbines 4, 5, and the gas turbine load command 19C is set to
The signal 45 is output to the AND circuit 44 when the following occurs.

When the command 19B and the signal 45 from the hold circuit 43 are input to the AND circuit 44 together,
The bypass signal 46 is output from the ND circuit 44 to the OR circuit 47.

Further, a bypass signal 46 from the AND circuit 44 is input to a timer 48, and the hold circuit 38 is delayed by a time set by the timer 48.
Is input as a reset signal to the reset side R.

Further, the gas turbine start command 19A is input to the OR circuit 47, and the bypass signal 46
Any one of the gas turbine start command 19A and the OR circuit 47
, A reset signal 49 is output from the OR circuit 47 to the reset side R of the hold circuit 34 of the start-up switching circuit 22.

Next, the operation of the above embodiment will be described.

FIG. 3 shows the bypass valve 15 and the inlet valve 16 serving as the intercooler-side valve 16 when the gas turbine is started, during normal operation of the gas turbine, and when the gas turbine is stopped.
FIG. 6 is an operation diagram showing opening and closing operations of a and the outlet valve 16b.

At the time of starting the gas turbine, as shown in FIG. 2, when a gas turbine start command 19A is issued, the command 19A is input to the set side S of the hold circuit 24 of the start-time switching circuit 22. However, since the outlet temperature 18 of the high-pressure air compressor 3 is low at the initial stage of startup and is, for example, 150 ° C. or less of the set temperature T, the signal 26 is not output, and therefore the intercooler operation signal 28 is output from the AND circuit 25. Therefore, the fully closed signal 35 from the AND circuit 29 is not output.

For this reason, since there is no full-close signal 35 from the hold circuit 34, the full-open signal 37 is output from the knot circuit 36, and the bypass valve 15 is fully opened.

Further, since the intercooler operation signal 28 is not output, the fully open signal 39 from the hold circuit 38 of the stop-time switching circuit 23 is not output, so that the fully closed signal 42 from the knot circuits 40 and 41 is not output. The output is output to the inlet valve 16a and the outlet valve 16b of the intercooler side valve 16, and the inlet valve 16a and the outlet valve 16b are fully closed.

As described above, the humid air gas turbine equipment is started while the compressed air 7 guided from the low-pressure air compressor 2 to the high-pressure air compressor 3 in FIG. 1 is bypassed to the bypass pipe 14a. The compressed air 7 is prevented from being supercooled by the intercooler 8, so that the combustion of the combustor 10 can be stabilized.

When the flow rate of the compressed air 7 increases with an increase in the gas turbine load command, the high-pressure air compressor 3
When the outlet temperature 18 gradually rises and reaches, for example, 150 ° C. of the set temperature T, a signal 26 is output to the timer 27, and after a predetermined time delay by the timer 27, the signal 26 is output to the AND circuit 25. You.

Then, the gas turbine start command 19A from the hold circuit 24 and the signal 26 from the timer 27 are input to the AND circuit 25 together, so that the AN
The D circuit 25 outputs the intercooler operation signal 28 to the AND circuit 29. At this time, the inlet valve 16a
And the outlet valve 16b are in the fully closed state.
3 does not output the intercooler side valve fully open signal 32,
Therefore, the fully closed signal 35 from the AND circuit 29 is not output.

When the intercooler operation signal 28 from the AND circuit 25 is turned off, the hold circuit 38
, The inlet valve 16a and the outlet valve 16b are simultaneously fully opened by the fully opened signal 39.

When the inlet valve 16a and the outlet valve 16b are fully opened, the signals 30 and 31 of the start-up switching circuit 22 are ANDed.
By being input to the circuit 33, the intercooler side valve fully open signal 32 is output to the AND circuit 29, whereby the AND circuit 29 outputs the fully closed signal 35 to the bypass valve 15 to fully close the bypass valve 15. . As described above, the temperature of the compressed air 7 at the outlet of the high-pressure air compressor 3 is equal to the set temperature T.
After that, normal operation in the humid air gas turbine facility is performed.

As described above, the gas turbines 4, 5
When switching from the startup state to the normal operation state, the inlet valve 1
6a and the outlet valve 16b are fully opened before the bypass valve 15
Are completely closed, the switching can be performed safely.

When the gas turbine stop command 19B is issued from the normal operation state, the command 19B is output to the AND circuit 44 via the hold circuit 43. However, at this time, since the gas turbine load command 19C is usually higher than the set load P, for example, 40 MWD, the signal 45 becomes AN
The signal is not input to the D circuit 44, and the bypass signal 46 is not output from the AND circuit 44.

On the other hand, the gas turbine stop command 19B is applied to the reset side R of the hold circuit 24 of the start-up switching circuit 22.
, There is no signal output from the hold circuit 24 to the AND circuit 25 due to the absence of the gas turbine start command 19A. Thereby, the AND circuit 25
Intercooler operation signal 28 from
The fully closed signal 35 from the circuit 29 also disappears. However, since the reset signal 49 has not yet been input to the hold circuit 34, the fully closed signal 35 is held, and the bypass valve 15 maintains the fully closed state.

Although the intercooler operation signal 28 from the AND circuit 25 is not input to the hold circuit 38 of the stop-time switching circuit 23, the bypass signal 46 is not input to the hold circuit 38 yet. 3
9 is held, and thus the inlet valve 16a and the outlet valve 16b maintain the fully open state.

When the gas turbine load command 19C gradually decreases and becomes lower than the set load P, for example, 40 MWD,
The output of the signal 45 causes the command 19B from the hold circuit 43 based on the gas turbine stop command 19B.
And the signal 45 are input to the AND circuit 44, so that the bypass signal 46 is output from the AND circuit 44.

When the bypass signal 46 is output, the reset signal 49 is immediately input to the reset side R of the hold circuit 34 by the OR circuit 47, and the hold circuit 34 is reset. The full-close signal 35 disappears, and the bypass valve 15 is fully opened by the full-open signal 37 from the knot circuit 36.

Also, when the bypass signal 46 is
8, after a predetermined time delay from the full opening of the bypass valve 15, the bypass signal 46 is input to the reset side R of the hold circuit 38, and the hold circuit 38 is reset. The full open signal 39 of the outlet valve 16a and the outlet valve 16b disappears.
6a and the outlet valve 16b are fully closed.

Thus, when the gas turbine load command 19C becomes lower than the set load P when the gas turbines 4 and 5 in FIG. 1 are stopped, the low-pressure air compressor 2
Is bypassed to the bypass pipe 14a, so that when the humid air gas turbine equipment is stopped, the compressed air 7 is prevented from being supercooled by the intercooler 8, and thus the combustor 10 Combustion can be stabilized.

As described above, the gas turbines 4, 5
When the gas turbines 4 and 5 are stopped from the normal operation state, since the bypass valve 15 is fully opened and then the inlet valve 16a and the outlet valve 16b are fully closed, the switching can be performed safely.

When the gas turbine start command 19A is issued again from the gas turbine stop state, the command 19
A resets the hold circuit 43 of the stop-time switching circuit 23, and resets the hold circuit 34 of the start-up switching circuit 22 by a reset signal 49 from the OR circuit 47.

As described above, when the humid air gas turbine equipment is started, when the flow rate of the compressed air 7 until the outlet temperature 18 of the high-pressure air compressor 3 reaches the set temperature T is small, the compressed air 7 is supplied to the bypass pipe 14a. To prevent the compressed air 7 from being overcooled by the intercooler 8, and when the humid air gas turbine equipment is stopped, when the gas turbine load command 19C drops to the set load P, the flow rate decreases. The compressed air 7 is bypassed to the bypass pipe 14a to prevent the compressed air 7 from being supercooled by the intercooler 8, so that when the humid air gas turbine equipment is started or stopped,
Due to the decrease in the temperature of the compressed air 7, it is possible to reliably prevent a problem such as unstable combustion of the combustor 10 or misfire, which has conventionally occurred.

[0053]

According to the present invention, when the humid air gas turbine equipment is started and stopped, the compressed air is bypassed to the bypass pipe, thereby preventing the compressed air from being supercooled by the intercooler. Thus, an excellent effect of reliably preventing the occurrence of problems such as instability of combustion of the combustor or misfiring which occur when starting or stopping the conventional wet gas turbine equipment can be achieved.

[Brief description of the drawings]

FIG. 1 is an overall block diagram illustrating an example of an embodiment of the present invention.

FIG. 2 is a logic circuit diagram of the control device of FIG. 1;

FIG. 3 is an operation diagram showing an opening / closing operation state of a bypass valve and an inlet valve and an outlet valve which are intercooler-side valves when the gas turbine is started, the gas turbine is normally operated, and the gas turbine is stopped.

FIG. 4 is an overall block diagram showing an example of a conventional humid air gas turbine facility.

[Explanation of symbols]

 2 low-pressure air compressor 3 high-pressure air compressor 4 high-pressure gas turbine 5 low-pressure gas turbine 7 compressed air 8 intercooler 9 humidification tower 10 combustor 12 gas 14 air pipe 14a bypass pipe 14b air pipe 15 bypass valve 16 intercooler side valve 17 Thermometer 18 Outlet temperature 19C Gas turbine load command 21 Controller 22 Start-up switching circuit 23 Stop-time switching circuit P set load T set temperature

Claims (1)

[Claims] The compressed air from a low-pressure air compressor is cooled by an intercooler and supplied to a high-pressure air compressor. The compressed air from the high-pressure air compressor is humidified by a humidification tower and introduced into a combustor. An intercooler switching control device for humid air gas turbine equipment that performs combustion and sequentially introduces post-combustion gas into a high-pressure gas turbine and a low-pressure gas turbine, wherein compressed air compressed by a low-pressure air compressor is passed through an intercooler. A bypass pipe provided to bypass the intercooler in an air pipe supplied to the high-pressure air compressor; a bypass valve provided in the bypass pipe; and an intercooler-side valve provided in an air pipe on the intercooler side of the bypass pipe. And a thermometer that detects the outlet temperature of the high-pressure air compressor. A start-up switching circuit that opens the valve, closes the intercooler side valve, closes the intercooler side valve when the high-pressure air compressor outlet temperature reaches the set temperature, and closes the bypass valve. A control device having a stop-time switching circuit that opens a bypass valve and closes an intercooler-side valve when the turbine load command falls below a set load. Control device.