JPH05157204A - Fuel control device for auxiliary boiler for a plurality of boiler systems - Google Patents

Abstract

PURPOSE:To prevent the occurrence of the delay in response of an auxiliary boiler by a method wherein a fuel preceding charge signal determined through reduction of a total effective fuel flow rate on the input heat side from a fuel equivalent amount on the output heat side is added to a fuel flow rate signal and based on an addition result, the opening of the flow rate regulating valve of the auxiliary boiler is regulated. CONSTITUTION:Based on steam flow rates 22 and 23 discharged from respective boilers, a fuel equivalent amount 26 on the output heat side of each boiler is determined and based on fuel flow rates 30 and 31 fed to respective boilers, a total effective fuel flow rate 36 on the input heat side is determined. Based on a deviation between the fuel equivalent amount 26 on the output heat side and the total effective fuel flow rate 36 on the input heat side, a fuel preceding charge signal 38 is determined. A fuel flow rate signal 17 is corrected by means of the fuel preceding charge signal 38, and by means of the obtained correction fuel flow rate signal 40, a fuel flow rate regulating valve 18 of an auxiliary boiler is controlled. This constitution prevents the occurrence of the delay in response of the auxiliary boiler.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel control device for an auxiliary boiler in a multiple boiler facility.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a multiple boiler installation.
It is a cogeneration facility that drives the generator 2 with the gas turbine 1 to supply electricity to the power supply facility 4 in the facility 3 and uses the heat of the exhaust gas of the gas turbine 1 to generate steam with the exhaust heat recovery boiler 5. Is generated and steam is fed to the heat supply equipment 6 in the facility 3.

Since the above-mentioned cogeneration equipment is generally of a power-driven type, the amount of steam fluctuates according to changes in the amount of power generation. Therefore, an auxiliary boiler 7 is further provided to control the amount of steam. It is designed to be stable.

Reference numeral 8 in FIG. 3 denotes a main steam pipe for sending steam from the exhaust heat recovery boiler 5 and the auxiliary boiler 7 to the heat supply equipment 6.

The auxiliary boiler 7 is, as shown in FIG.
The pressure detector 9 is provided on the outlet side of the auxiliary steamer 7 of the main steam pipe 8, the pressure detection signal 10 detected by the pressure detector 9 is sent to the subtractor 12 inside the control device 11, and the subtractor 12 sets the setter 13 The deviation signal 15 is compared with the pressure setting signal 14 from the above, and the obtained deviation signal 15 is converted into a fuel flow rate signal 17 by a controller 16 such as a proportional integral controller to adjust the opening degree of the fuel flow rate adjusting valve 18. Thus, the pressure of the steam inside the main steam pipe 8 is controlled to be kept constant.

In FIG. 4, 19 is a fuel supply passage for the auxiliary boiler 7, and 42 is a fuel supply passage for the gas turbine 1. In addition to the above-mentioned cogeneration equipment, there are various types of multiple boiler equipment.

[0007]

However, the above-described conventional fuel control device for the auxiliary boiler in the multiple boiler facility has the following problems.

That is, since it takes a considerable amount of time from the change in the output of the gas turbine 1 to the change in the evaporation amount of the exhaust heat recovery boiler 5 and the change in the steam pressure in the main steam pipe 8, it takes a considerable amount of time. 8 If the opening of the fuel flow rate adjusting valve 18 is adjusted after detecting the change in the pressure of the steam inside, the output change of the gas turbine 1 itself cannot be dealt with, resulting in a response delay. Will wake up.

Therefore, there is a problem that the steam pressure in the main steam pipe 8 is not stable.

In view of the above situation, it is an object of the present invention to provide a fuel control device for an auxiliary boiler in a multi-boiler facility that can eliminate a response delay.

[0011]

The present invention is directed to an auxiliary boiler 7
A plurality of boilers 43, 7 including
In a multi-boiler facility in which steam outlets of the main steam pipe 8 are connected, a pressure detector 9 is provided at the most downstream position of the main steam pipe 8, and a pressure detection signal detected by the pressure detector 9 is provided. 10 is provided with a subtracter 12 that compares the pressure setting signal 14 set in the setting device 13 to obtain a deviation, and a controller 16 that converts the obtained deviation signal 15 into a fuel flow rate signal 17 is provided. , 7 are provided with steam flow rate detectors 20 and 21 individually at the steam outlets, and the respective steam flow rate detectors 20 and 2 are provided.
1, an adder 25 for adding the vapor flow rates 22 and 23 detected in 1 to obtain a total vapor flow rate 24, and a function generator 27 for converting the total vapor flow rate 24 into a fuel equivalent amount 26 on the heat output side are provided. Fuel flow rate detectors 28 and 29 are provided on the fuel supply paths 42 and 19 of the boilers 43 and 7, respectively.
The fuel flow rates 30 and 31 detected by
Effective fuel flow rate 3 effectively used for evaporation every 3 and 7
2 and 33 are provided with function generators 34 and 35, and an adder 37 for adding the respective effective fuel flow rates 32 and 33 to obtain a total effective fuel flow rate 36 on the heat input side is provided. A subtractor 39 is provided that subtracts the total effective fuel flow rate 36 on the heat input side from the fuel equivalent amount 26 to obtain a fuel advance input signal 38, and adds the fuel advance input signal 38 to the fuel flow rate signal 17 to add fuel to the auxiliary boiler 7. The present invention relates to a fuel control device for an auxiliary boiler in a multi-boiler facility, which is provided with an adder 41 for obtaining a corrected fuel flow rate signal 40 for adjusting the opening of the flow rate adjusting valve 18.

[0012]

According to the present invention, a plurality of boilers 43, 7 including an auxiliary boiler 7 are provided, and a steam outlet of each of the boilers 43, 7 is connected by a main steam pipe 8. The pressure detector 9 provided at the most downstream position of 8 detects the pressure of the steam inside the main steam pipe 8, and the subtractor 12 detects the pressure detection signal 10 from the pressure detector 9 and the pressure set in the setter 13. The deviation from the setting signal 14 is taken, and the obtained deviation signal 15 is converted into a fuel flow rate signal 17 by the controller 16.

Further, steam flow rate detectors 20 and 21 are individually provided at the steam outlets of the boilers 43 and 7, and the steam flow rates 22 and 23 detected by the steam flow rate detectors 20 and 21 are added to the adder 2 respectively.
5 is added to obtain the total steam flow rate 24, and the total steam flow rate 2
4 is converted by the function generator 27 into the fuel equivalent amount 26 on the heat output side.

Further, the fuel supply path 4 of each boiler 43, 7
2 and 19 are provided with fuel flow rate detectors 28 and 29, and the fuel flow rates 30 and 31 detected by the fuel flow rate detectors 28 and 29 are effectively evaporated by the function generators 34 and 35 for each boiler 43, 7. The effective fuel flow rates 32 and 33 used are converted, and the effective fuel flow rates 32 and 33 are added by an adder 37 to obtain a total effective fuel flow rate 36 on the heat input side.

Then, the total effective fuel flow rate 36 on the heat input side is subtracted from the fuel equivalent amount 26 on the heat output side by the subtractor 39 to obtain the fuel preceding injection signal 38, and the fuel flow rate signal 17 is supplied to the fuel flow rate signal 17 by the adder 41. The preceding injection signal 38 is added to obtain the corrected fuel flow rate signal 40, and the opening degree of the fuel flow rate adjusting valve 18 of the auxiliary boiler 7 is adjusted based on the corrected fuel flow rate signal 40.

[0016]

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

1 and 2 show an embodiment of the present invention.

Further, in the drawings, the same components as those in FIGS. 3 and 4 are designated by the same reference numerals and the description thereof will be omitted, and only the configuration unique to the present invention will be described below.

Each boiler in a plurality of boiler facilities (in the case of the cogeneration facility in FIG. 3 as an example, the combination of the gas turbine 1 and the exhaust heat recovery boiler 5 is counted as one boiler 43 in terms of function, and the auxiliary boiler 7 is also included. The steam flow rate detector 20, 2 is provided at the steam outlet of the boiler (counted as one boiler).
1 is provided, and the adder 25 for adding the steam flow rates 22 and 23 detected by the steam flow rate detectors 20 and 21 to obtain the total steam flow rate 24 is provided, and the total steam flow rate 24 is set to the fuel equivalent amount 26 on the heat output side. A function generator 27 for conversion is provided.

Further, the fuel supply passages 42 of the boilers 43, 7 are
19 is provided with fuel flow rate detectors 28 and 29, and the fuel flow rates 30 and 31 detected by the fuel flow rate detectors 28 and 29 are the amount of fuel effectively used for evaporation in each boiler 43, 7, that is, Function generator 3 for converting fuel flow rate 32, 33
4, 35 are provided, and an adder 37 for adding the respective effective fuel flow rates 32, 33 to obtain a total effective fuel flow rate 36 on the heat input side is provided.

Further, a subtracter 39 is provided for subtracting the total effective fuel flow rate 36 on the heat input side from the fuel equivalent amount 26 on the heat output side to obtain a fuel advance input signal 38. 38 to add corrected fuel flow rate signal 40
An adder 41 for determining

Next, the operation will be described.

The process from the detection of the change in the pressure of the steam inside the main steam pipe 8 to the adjustment of the opening of the fuel flow rate adjusting valve 18 is the same as that shown in FIGS.

Further, in the present invention, the steam flow rate detectors 20 and 21 provided at the steam outlets of the boilers 43 and 7 are used for the boilers 4.
The steam flow rates 22 and 23 of 3 and 7 are detected, and the steam flow rate 2
2, 23 are added by the adder 25 to obtain the total steam flow rate 24, and the total steam flow rate 24 is converted by the function generator 27 into the fuel equivalent amount 26 on the heat output side.

Further, the fuel supply paths 42 of the boilers 43, 7 are
The fuel flow rate detectors 28 and 29 provided in 19 are used for each boiler 4
The fuel flow rates 30 and 31 of 3 and 7 are detected, and the fuel flow rate 3
0, 31 is converted into the amount of fuel effectively used for evaporation in each boiler 43, 7 by the function generators 34, 35, that is, the effective fuel flow rates 32, 33, and the effective fuel flow rates 32, 33 are added. The total effective fuel flow rate 36 on the heat input side is obtained by addition in the device 37.

Then, the total effective fuel flow rate 36 on the heat input side is subtracted from the fuel equivalent amount 26 on the heat output side by a subtractor 39 to obtain a fuel advance input signal 38.

Finally, the adder 41 adds the preceding fuel input signal 38 to the fuel flow rate signal 17 to obtain the corrected fuel flow rate signal 40.
And the opening of the fuel flow rate adjusting valve 18 of the auxiliary boiler 7 is adjusted based on the corrected fuel flow rate signal 40.

In this way, the fuel preceding injection signal 38 is obtained by taking the deviation between the fuel equivalent amount 26 on the heat output side of each boiler 43, 7 and the total effective fuel flow rate 36 on the heat input side, and the preceding fuel injection signal 38 is obtained. Since the fuel flow rate signal 17 to the fuel flow rate adjusting valve 18 of the auxiliary boiler 7 is corrected by 38, the response delay of the auxiliary boiler 7 can be prevented, so that the pressure inside the main steam pipe 8 is always maintained. Can be kept constant.

The present invention is not limited to the above-described embodiment, but the fuel equivalent amount 26 on the heat output side and the total effective fuel flow rate 36 on the heat input side are individually added to the fuel flow rate signal 17. Of course, it may be subtracted, it is effective for general equipment provided with a plurality of boilers, and other various changes may be made without departing from the scope of the present invention.

[0030]

As described above, according to the fuel control device for the auxiliary boiler in the multi-boiler facility of the present invention, the excellent effect that the response delay of the auxiliary boiler 7 can be prevented can be obtained.

[Brief description of drawings]

FIG. 1 is a control system diagram of an embodiment of the present invention.

FIG. 2 is an overall view of a multi-boiler facility using FIG.

FIG. 3 is an overall view of a conventional multi-boiler facility.

FIG. 4 is a control system diagram of FIG.

[Explanation of symbols]

 7,43 Boiler (reference numeral 7 is an auxiliary boiler) 8 Main steam pipe 9 Pressure detector 10 Pressure detection signal 12 Subtractor 13 Setter 14 Pressure setting signal 15 Deviation signal 16 Controller 17 Fuel flow rate signal 18 Fuel flow rate control valve 19, 42 Fuel supply channel 20,21 Steam flow rate detector 22,23 Steam flow rate 24 Total steam flow rate 25 Adder 26 Fuel equivalent amount on heat output side 27 Function generator 28,29 Fuel flow rate detector 30,31 Fuel flow rate 32,33 Effective fuel flow rate 34,35 Function generator 36 Total effective fuel flow rate 37 Adder 38 Fuel preceding injection signal 39 Subtractor 40 Corrected fuel flow rate signal 41 Adder

Claims (1)

[Claims] 1. A plurality of boilers 43 including an auxiliary boiler 7,
7, the steam outlet of each boiler 43, 7 is connected to the main steam pipe 8
In a multi-boiler system connected by, a pressure detector 9 is provided at the most downstream position of the main steam pipe 8, and the pressure detection signal 10 detected by the pressure detector 9 and the pressure set in the setter 13 are set. Subtractor 1 that compares the setting signal 14 to obtain the deviation
2 is provided, and a controller 16 for converting the obtained deviation signal 15 into a fuel flow rate signal 17 is provided, and each boiler 43, 7 is provided.
The steam flow rate detectors 20 and 21 are individually provided at the steam outlets of the steam flow rates 2 detected by the steam flow rate detectors 20 and 21.
Adder 2 for adding 2 and 23 to obtain total steam flow rate 24
5 is provided, and the total vapor flow rate 24 is set to the fuel equivalent amount 26 on the heat output side.
A function generator 27 for converting into
Fuel flow rate detectors 28 are provided in the fuel supply passages 42 and 19 of 3, 7 respectively.
29, and function generators 34, 35 for converting the fuel flow rates 30, 31 detected by the fuel flow rate detectors 28, 29 into effective fuel flow rates 32, 33 effectively used for evaporation for each boiler 43, 7. And the respective effective fuel flow rates 32 and 33 are added to obtain the total effective fuel flow rate 36 on the heat input side.
7 and a subtracter 39 for subtracting the total effective fuel flow rate 36 on the heat input side from the fuel equivalent amount 26 on the heat output side to obtain a fuel advance input signal 38, and adding the fuel advance input to the fuel flow rate signal 17. Corrected fuel flow rate signal 4 for adjusting the opening of the fuel flow rate adjusting valve 18 of the auxiliary boiler 7 by adding the signal 38
A fuel control device for an auxiliary boiler in a multi-boiler facility, characterized in that an adder 41 for determining 0 is provided.