Fuel oil supply device

Abstract

The present invention relates to a fuel oil supply device for supplying fuel oil to a combustor of a gas turbine. The fuel oil supply device is provided with: a pump for supplying fuel oil; a supply pressure regulating valve disposed on the downstream side of the pump and used for regulating the supply pressure of the fuel oil by the pump; and a plurality of flow rate regulating valves disposed on the downstream side of the supply pressure regulating valve and used for regulating the flow rate of the fuel oil supplied to a plurality of fuel nozzles of the combustor. A plurality of cavitation suppression parts are provided on the downstream side of each of the plurality of flow control valves. The opening degree of the flow adjusting valve is controlled according to a first pressure of the fuel oil on the upstream side of the flow adjusting valve, a second pressure on the downstream side of the flow adjusting valve, and the flow rate of the fuel oil supplied to the fuel nozzle.

Description

Technical Field

[0001] The present invention relates to a fuel oil supply device for supplying fuel oil to a burner of a gas turbine.

[0002] This application claims priority based on Japanese Patent Application No. 2022-201808 filed with the Japan Patent Office on December 19, 2022, and incorporates its content herein. Background Art

[0003] In a gas turbine, a turbine is driven by combustion gas generated by burning fuel in a burner. In a typical gas turbine, gas fuel operation using gas fuel as fuel is mainly performed, but there is also a gas turbine that performs fuel oil operation using fuel oil as a backup fuel. A fuel oil supply device for supplying fuel oil as fuel for oil firing, for example, includes: a supply pressure regulating valve for regulating the supply pressure of fuel oil from a fuel oil supply source; and in each system of a plurality of fuel nozzles provided in the burner, a flow regulating valve for regulating the flow rate of fuel oil and a differential pressure regulating valve for regulating the differential pressure between the upstream side and the downstream side of the flow regulating valve. In this structure, a flow regulating valve and a differential pressure regulating valve are provided for each supply system corresponding to the fuel nozzle, so the number of regulating valves as a whole (the total number of the supply pressure regulating valve, the flow regulating valve, and the differential pressure regulating valve) increases, and thus the initial cost at the time of introduction becomes high.

[0004] As one method for solving such a problem, it can be considered to reduce the number of regulating valves by sharing a plurality of differential pressure regulating valves provided in each supply system in the above structure. That is, by providing a pressure regulating valve shared in each supply system on the downstream side of the supply pressure regulating valve, the number of regulating valves of the fuel oil supply device can be reduced compared with the case where a differential pressure regulating valve is provided for each supply system. For example, in Patent Document 1, although it is a structure for supplying gas fuel as fuel instead of fuel oil, a structural example is disclosed in which the number of regulating valves is reduced by reducing the differential pressure regulating valve disposed upstream of the flow regulating valve for regulating the fuel flow rate for each fuel nozzle.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: International Publication No. 2013 / 105406 Summary of the Invention

[0008] Technical Problem to be Solved by the Invention

[0009] As described above, in the fuel oil supply system corresponding to each fuel nozzle, when the differential pressure regulating valve is reduced, the number of pressure reduction stages based on the regulating valve in each supply system is reduced (that is, in the structure having a differential pressure regulating valve and a flow regulating valve, it is a two-stage pressure reduction. In contrast, if the differential pressure regulating valve is reduced, it becomes a one-stage pressure reduction based on the flow regulating valve). As a result, the pressure difference between the upstream side pressure and the downstream side pressure of the flow regulating valve becomes larger, and cavitation may occur in the fuel oil passing through the flow regulating valve.

[0010] At least one embodiment of the present invention has been completed in view of the above situation, and its object is to provide a fuel oil supply device that can prevent cavitation from occurring with a flow regulating valve even when the number of pressure reduction stages of the fuel oil becomes smaller due to a reduction in the number of valves in the fuel oil supply system for each fuel nozzle.

[0011] Means for Solving Technical Problems

[0012] To solve the above problems, a fuel oil supply device according to at least one embodiment of the present invention is for supplying fuel oil to a burner of a gas turbine, and the fuel oil supply device includes:

[0013] A pump for supplying the fuel oil;

[0014] A supply pressure regulating valve disposed downstream of the pump for regulating the supply pressure of the fuel oil based on the pump;

[0015] A plurality of flow regulating valves disposed downstream of the supply pressure regulating valve for respectively regulating the flow rate of the fuel oil supplied to a plurality of fuel nozzles of the burner;

[0016] A plurality of cavitation suppression parts provided downstream of each of the plurality of flow regulating valves; and

[0017] An opening degree control part for controlling the opening degree of the flow regulating valve according to a first pressure of the fuel oil on the upstream side of the flow regulating valve, a second pressure on the downstream side of the flow regulating valve, and the flow rate of the fuel oil supplied to the fuel nozzle.

[0018] Advantages of the Invention

[0019] According to at least one embodiment of the present invention, it is possible to provide a fuel oil supply device that can prevent cavitation from occurring with a flow regulating valve even when the number of pressure reduction stages of the fuel oil becomes smaller due to a reduction in the number of valves in the fuel oil supply system for the fuel nozzle. Description of the Drawings

[0020] Figure 1It is a schematic structural diagram of a gas turbine power plant related to an embodiment.

[0021] Figure 2 is Figure 1 a schematic structural diagram of the fuel oil supply device of

[0022] Figure 3 is Figure 2 a schematic structural diagram of the fuel supply device related to a comparative example of

[0023] Figure 4 is a schematic diagram showing Figure 2 the cross-sectional structure of the cavitation suppression part of

[0024] Figure 5 is a block diagram showing Figure 2 the functional structure of the control device of the fuel oil supply device of

[0025] Figure 6 is a diagram showing Figure 5 the operation logic of the second pressure calculation part of

[0026] Figure 7 is a diagram showing the operation logic for calculating Figure 6 the chamber pressure of

[0027] Figure 8 is a chart showing the relationship among the first pressure, the second pressure, the chamber pressure, the pressure loss of the cavitation suppression part, and the nozzle pressure loss. Specific Embodiments

[0028] Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the structures described or shown in the drawings as embodiments are not intended to limit the scope of the present invention thereto, but are merely illustrative examples.

[0029] Figure 1 It is a schematic structural diagram of a gas turbine power plant 1 related to an embodiment. The gas turbine power plant 1 includes a compressor 2, a burner 3, a turbine 4, a fuel oil supply device 5, and a generator 6.

[0030] The compressor 2 is a structure for sucking air (atmosphere) from the outside to generate compressed air. The compressed air generated by the compressor 2 is supplied to the burner 3. The burner 3 burns by mixing the compressed air supplied from the compressor 2 and fuel oil as fuel supplied from the fuel oil supply device 5, thereby generating high-temperature combustion gas. The turbine 4 is driven by receiving the supply of the high-temperature gas generated by the burner 3, and thus outputs a rotational driving force from a rotating shaft 7. The rotating shaft 7 transmits the rotational driving force output from the turbine 4 to the generator 6, and thus the generator 6 generates electricity.

[0031] Next, with reference toFigure 2 The specific structure of the fuel oil supply device 5 will be described. Figure 2 is Figure 1 A schematic structural diagram of the fuel oil supply device 5. The fuel oil supply device 5 is a structure for supplying fuel oil as fuel to the burner 3. In addition, in the burner 3, other fuels such as gaseous fuel are mainly used, and it can be configured to use the fuel oil supplied from the fuel oil supply device 5 as an alternative fuel.

[0032] The fuel oil supply device 5 is configured to be able to supply fuel oil to the fuel nozzles provided in the burner 3. The burner 3 can be provided with a variety of fuel nozzles. In the present embodiment, the burner 3 is provided with a first main nozzle 11M1 and a second main nozzle 11M2 for premixed combustion for the purpose of reducing NOx, and a pilot nozzle 11P for diffusion combustion for the purpose of stabilizing combustion and the like as fuel nozzles.

[0033] In addition, the burner 3 may be provided with a top hat nozzle as a fuel nozzle for premixed combustion for the purpose of further reducing NOx in addition to these fuel nozzles. In this case, the fuel oil supply device 5 can also supply fuel oil to the top hat nozzle. Thus, as the structure of the burner 3 provided with a top hat nozzle, for example, a known structure such as the structure shown in Japanese Patent Laid-Open No. 2007-77867 can be used, and it is not particularly limited.

[0034] The fuel oil supply device 5 includes a common system 10C, a first main fuel supply system 10M1, a second main fuel supply system 10M2, and a pilot fuel supply system 10P.

[0035] The common system 10C is a system for supplying fuel oil to the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P, and includes a fuel oil supply pipeline 15. One end side of the fuel oil supply pipeline 15 is connected to a fuel oil supply source (not shown) as the supply source of fuel oil, and the other end side is branched and connected to the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P. A pump 21 is provided on the fuel oil supply pipeline 15, and by operating the pump 21, it is possible to supply fuel oil from the fuel oil supply source to the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P.

[0036] An oil return line 18 branches off at a position downstream of the pump 21 in the fuel oil supply line 15. The oil return line 18 constitutes an oil return system 23 for returning at least a part of the fuel oil flowing in the fuel oil supply line 15 to the fuel oil supply source. A supply pressure regulating valve 19 is provided on the oil return line 18. The supply pressure regulating valve 19 is a valve capable of controlling the opening degree according to a control signal from the control device 50. By changing the flow rate of the fuel oil returned to the fuel oil supply source via the oil return line 18 according to its opening degree, the pressure of the fuel oil supplied from the fuel oil supply line 15 to each system (the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P) can be adjusted (the first pressure P1 of the fuel oil upstream of the first main flow regulating valve 13M1, the second main flow regulating valve 13M2, and the pilot flow regulating valve 13P).

[0037] In addition, a pressure sensor 20 for measuring the first pressure P1 of the fuel oil in the fuel oil supply line 15 and a temperature sensor 22 for measuring the temperature T are provided in the common system 10C.

[0038] The first main fuel supply system 10M1 is a system for supplying fuel oil to the first main nozzle 11M1. One end side of the first main fuel supply system 10M1 is connected to the fuel oil supply line of the common system 10C, and the other end side is connected to the first main manifold 12M1 for supplying fuel oil to each first main nozzle 11M1. Moreover, a first main flow regulating valve 13M1 for controlling the flow rate of the fuel oil supplied to the first main nozzle 11M1 is provided in the first main fuel supply system 10M1. The first main flow regulating valve 13M1 is a valve for regulating the flow rate of the fuel oil supplied to the first main nozzle 11M1. The first main manifold 12M1 is a structure for distributing the fuel oil supplied from the first main fuel supply system 10M1 to a plurality of first main nozzles 11M1.

[0039] The second main fuel supply system 10M2 is a system for supplying fuel oil to the second main nozzle 11M2. One end side of the second main fuel supply system 10M2 is connected to the fuel oil supply line 15 of the common system 10C, and the other end side is connected to the second main manifold 12M2 for supplying fuel oil to each second main nozzle 11M2. Moreover, a second main flow regulating valve 13M2 for controlling the flow rate of the fuel oil supplied to the second main nozzle 11M2 is provided in the second main fuel supply system 10M2. The second main flow regulating valve 13M2 is a valve for regulating the flow rate of the fuel oil supplied to the second main nozzle 11M2. The second main manifold 12M2 is a structure for distributing the fuel oil supplied from the second main fuel supply system 10M2 to a plurality of second main nozzles 11M2.

[0040] The pilot fuel supply system 10P is a system that supplies fuel oil to the pilot nozzle 11P. One end side of the pilot fuel supply system 10P is connected to the fuel oil supply pipeline 15 of the common system 10C, and the other end side is connected to the pilot manifold 12P that supplies fuel to the pilot nozzle 11P. Moreover, a pilot flow regulating valve 13P for controlling the flow rate of the fuel oil is provided in the pilot fuel supply system 10P. The pilot flow regulating valve 13P is a valve that regulates the flow rate of the fuel oil supplied to the pilot nozzle 11P. The pilot manifold 12P is a structure for distributing the fuel oil supplied from the pilot fuel supply system 10P to a plurality of pilot nozzles 11P.

[0041] In addition, the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P are respectively provided with a differential pressure sensor 16 for detecting the differential pressure ΔP between the upstream pressure (the first pressure P1) and the downstream pressure (the second pressure P2) of the first main flow regulating valve 13M1, the second main flow regulating valve 13M2, and the pilot flow regulating valve 13P. And pressure sensors 17 for detecting the second pressure P are respectively provided on the downstream sides of the first main flow regulating valve 13M1, the second main flow regulating valve 13M2, and the pilot flow regulating valve 13P.

[0042] Moreover, the fuel oil supply device 5 further includes a water injection device 40 for reducing NOx by injecting water into at least a part of the plurality of fuel nozzles. In the present embodiment, the water injection device 40 is configured to inject water into the first main nozzle 11M1 and the second main nozzle 11M2 among the fuel nozzles of the burner 3. Specifically, the water injection device 40 has a water supply source 42 capable of supplying water and a water supply pipeline 44 connecting from the water supply source 42 to the first main nozzle 11M1 and the second main nozzle 11M2.

[0043] Here, Figure 3 is Figure 2 a schematic structural diagram of a fuel oil supply device 5' according to a comparative example. In the fuel oil supply device 5', in the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P, first main differential pressure regulating valves 14M1, second main differential pressure regulating valves 14M2, and pilot differential pressure regulating valves 14P are respectively provided at positions more upstream than the first main flow regulating valve 13M1, the second main flow regulating valve 13M2, and the pilot flow regulating valve 13P. The first main differential pressure regulating valve 14M1, the second main differential pressure regulating valve 14M2, and the pilot differential pressure regulating valve 14P are valves whose opening degrees are controlled to adjust the differential pressure ΔP between the upstream pressure (the first pressure P1) and the downstream pressure (the second pressure P2) of each flow regulating valve to a specified value.

[0044] In addition, in Figure 3In the fuel oil supply device 5' related to the comparative example shown, for the structure corresponding to the fuel oil supply device 5 shown, the same reference numerals are used, and repeated descriptions are appropriately omitted unless otherwise specified. Figure 2 In this comparative example, a flow control valve and a differential pressure control valve are provided for each supply system (the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P) corresponding to each fuel nozzle. Therefore, the number of control valves as a whole increases, and the initial cost at the time of introduction becomes high. Therefore, in the structure of the comparative example, it is possible to consider reducing the number of control valves by omitting the differential pressure control valves (the first main differential pressure control valve 14M1, the second main differential pressure control valve 14M2, and the pilot differential pressure control valve 14P). In this case, the number of pressure reduction stages based on the control valves in each supply system decreases (that is, as shown in

[0045] Figure 3 Figure 3 shown, in the structure in which a differential pressure control valve and a flow control valve are respectively provided for the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P, it is a two-stage pressure reduction. In contrast, if the differential pressure control valve is reduced, it becomes a one-stage pressure reduction based on the flow control valve). As a result, the pressure difference ΔP between the upstream side pressure (the first pressure P1) and the downstream side pressure (the second pressure P2) of the flow control valve becomes large, and there is a problem that cavitation is likely to occur in the fuel oil passing through the flow control valve.

[0046] To solve the problems in this comparative example, in the fuel oil supply device 5 according to the present embodiment, as shown in Figure 2 Figure 2

[0047] Figure 4 represents Figure 2Schematic diagram of the cross-sectional structure of the cavitation suppression section 30. In this structural example, the flow path through which the fuel oil passes through each flow control valve is constituted by a fixed wall surface 31 and a movable wall surface 32 elastically supported by the fixed wall surface 31. Since the movable wall surface 32 is elastically supported by the biasing member 33 such as a spring on the fixed wall surface 31, when the flow rate of the fuel oil is relatively small, the movable wall surface 32 approaches the center side of the flow path by the elastic force applied by the biasing member 33, and thus the cross-sectional area of the flow path becomes relatively smaller. On the other hand, when the flow rate of the fuel oil is relatively large, the pressure received by the movable wall surface 32 from the fuel oil resists the elastic force applied by the biasing member 33, and thus the movable wall surface 32 moves in a manner of approaching the outside from the center of the flow path, so that the cross-sectional area of the flow path increases. Therefore, the fuel oil supply device 5 according to the present embodiment, by including the above-described cavitation suppression section 30, makes the cross-sectional area of the flow path variable according to the flow rate of the fuel oil passing through each flow control valve (the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P), and thus can effectively suppress cavitation even when the pressure difference between the first pressure P1 on the upstream side and the second pressure P2 on the downstream side of each flow control valve becomes large.

[0048] In addition, each cavitation suppression section 30 may be integrally formed with the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P. In this case, by integrally forming the cavitation suppression section 30 with each flow control valve, the above-described structure can be realized in a compact form.

[0049] Next, the structure of the control device 50 for controlling the fuel oil supply device 5 having the above structure will be described.

[0050] The control device 50 is constituted by, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and a computer-readable storage medium, etc. Moreover, a series of processes for realizing various functions are stored, as an example, in the form of a program in a storage medium or the like, and various functions are realized by the CPU reading the program into the RAM or the like and performing information processing / arithmetic processing. In addition, the program may also be applied in a manner of being pre-installed in the ROM or other storage media, or in a state of being stored in a computer-readable storage medium, or in a manner of being distributed via a wired or wireless communication unit. The computer-readable storage medium refers to a magnetic disk, an optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, etc.

[0051] Figure 5 represents Figure 2Block diagram of the functional structure of the control device 50 of the fuel oil supply device. The control device 50 includes a supply pressure adjustment unit 52, a second pressure calculation unit 54, and an opening control unit 56.

[0052] The supply pressure adjustment unit 52 is a structure for adjusting the supply pressure of the fuel oil based on the common system 10C. Specifically, the supply pressure adjustment unit 52 controls the supply pressure of the fuel oil based on the pump 21 and the opening of the supply pressure regulating valve 19 so that the first pressure P1 detected by the pressure sensor 20 becomes a specified value, thereby adjusting the supply pressure (substantially equal to the first pressure P1) based on the common system 10C to become a specified value.

[0053] The second pressure calculation unit 54 is a structure for calculating the downstream pressure, i.e., the second pressure P2, of each flow control valve (the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P). Here, Figure 6 represents Figure 5 the operation logic diagram of the second pressure calculation unit 54, Figure 7 represents the operation logic diagram for calculating Figure 6 the chamber pressure Pc, Figure 8 is a chart showing the relationship between the first pressure P1, the second pressure P2, the chamber pressure Pc, the pressure loss Pk of the cavitation suppression unit 30, and the nozzle pressure loss Pn.

[0054] As Figure 6 shown, the downstream pressure, i.e., the second pressure P2, of each flow control valve (the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P) is calculated by subtracting the chamber pressure Pc, the pressure loss Pk of the cavitation suppression unit 30, and the nozzle pressure loss Pn from the upstream pressure, i.e., the first pressure P1, respectively. Here, as described above, the first pressure P1 is adjusted by controlling the pump 21 and the supply pressure regulating valve 19 in such a way that the detected value of the pressure sensor 20 becomes a specified value (in Figure 8 it is shown that the first pressure P1 is obtained by subtracting the pressure difference ΔPs of the supply pressure regulating valve 19 from the supply pressure P0 based on the pump 21).

[0055] And, as Figure 7 shown, the chamber pressure Pc is obtained, for example, by multiplying the result obtained by inputting the fuel flow command calculated according to the supply and demand signal for the gas turbine power plant 1 into the function FX3 by the result obtained by inputting the water injection amount of the water injection device 40 into the function FX4.

[0056] And, as Figure 6As shown, the pressure loss Pk of the cavitation suppression section 30 is obtained as the result of inputting the fuel oil flow rate into the function FX1. The function FX1 is prepared in advance as a function that defines the correlation between the specified fuel oil flow rate and the pressure loss Pk of the cavitation suppression section 30. In addition, the fuel oil flow rate is obtained by dividing the fuel flow rate command by the fuel density.

[0057] Furthermore, the nozzle pressure loss Pn is obtained by inputting the result of adding the above fuel oil flow rate and the water injection amount based on the water injection device 40 into the function FX2. The function FX2 is prepared in advance as a function that defines the correlation between the sum of the specified fuel oil flow rate and the water injection amount and the nozzle pressure loss Pn.

[0058] By subtracting the thus obtained chamber pressure Pc, the pressure loss Pk of the cavitation suppression section 30, and the nozzle pressure loss Pn from the upstream pressure of each flow control valve, i.e., the first pressure P1, the downstream pressure of each flow control valve, i.e., the second pressure P2, is obtained.

[0059] Return to Figure 5 The opening control section 56 is a structure for controlling the opening degrees of the respective flow control valves (the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P). The opening degrees of the respective flow control valves are calculated based on the first pressure P1 of the fuel oil on the upstream side of the flow control valve, the second pressure P2 on the downstream side of the flow control valve, and the flow rate of the fuel oil supplied to each fuel nozzle. As described above, the detection value of the pressure sensor 20 is adjusted to a specified value by the supply pressure adjustment section 52 to uniquely determine the first pressure P1. The second pressure P2 uses the calculation result of the above second pressure calculation section 54.

[0060] Thus, in the opening control section 56, the opening degrees of the respective flow control valves (the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P) are controlled based on the second pressure P2, but the second pressure P2 calculated in consideration of the pressure loss Pk of the cavitation suppression section 30 is used. Thereby, even when the cavitation suppression section 30 is provided on the downstream side of each flow control valve to suppress cavitation, the opening degrees of the respective flow control valves can be controlled based on the second pressure P2 with good accuracy.

[0061] Furthermore, as described above, the second pressure P2 used in the opening degree control of each flow control valve is calculated based on the chamber pressure Pc and the nozzle pressure loss Pn calculated in consideration of the water injection amount based on the water injection device 40. Thereby, also in the fuel oil supply device 5 provided with the water injection device 40, the opening degrees of the respective flow control valves can be controlled with good accuracy by calculating the chamber pressure Pc and the nozzle pressure loss Pn while considering the influence caused by water injection.

[0062] As described above, according to the above-described embodiments, it is possible to provide a fuel oil supply device 5 that can prevent cavitation from occurring in each flow control valve even when the number of pressure reduction stages of the fuel oil decreases due to a reduction in the number of valves in the fuel oil supply system for the fuel nozzle.

[0063] In addition, within the scope not departing from the gist of the present invention, the constituent elements in the above-described embodiments can be appropriately replaced with well-known constituent elements, and the above-described embodiments can be appropriately combined.

[0064] The content described in each of the above embodiments can be understood as follows, for example.

[0065] (1) A fuel oil supply device according to one aspect, which supplies fuel oil to a burner of a gas turbine, the fuel oil supply device comprising:

[0066] a pump for supplying the fuel oil;

[0067] a supply pressure regulating valve disposed downstream of the pump for regulating the supply pressure of the fuel oil based on the pump;

[0068] a plurality of flow control valves disposed downstream of the supply pressure regulating valve for respectively regulating the flow rate of the fuel oil supplied to a plurality of fuel nozzles provided in the burner;

[0069] a plurality of cavitation suppression portions provided downstream of each of the plurality of flow control valves; and

[0070] an opening degree control portion for controlling the opening degree of the flow control valve based on a first pressure of the fuel oil upstream of the flow control valve, a second pressure downstream of the flow control valve, and the flow rate of the fuel oil supplied to the fuel nozzle.

[0071] According to the aspect of (1) above, a cavitation suppression portion is provided downstream of the flow control valve provided for each supply system for supplying fuel oil to each fuel nozzle provided in the burner. Thus, even when the pressure difference between the upstream side and the downstream side of the flow control valve becomes large due to a reduction in the differential pressure regulating valve in each supply system, it is possible to effectively prevent cavitation from occurring in the fuel oil passing through the flow control valve.

[0072] (2) According to the aspect of (1) above, in another aspect,

[0073] the second pressure includes the pressure loss of the cavitation suppression portion calculated based on the flow rate of the fuel oil.

[0074] According to the method in (2) above, the second pressure used in the opening control of the flow control valve includes the pressure loss in the cavitation suppression section. In this way, by considering the influence caused by arranging the cavitation suppression section on the downstream side of the flow control valve for the opening control of the flow control valve, cavitation can be prevented, and the flow control of the fuel oil supplied to each fuel nozzle can be implemented with good accuracy.

[0075] (3) According to the method in (2) above, in another method,

[0076] The second pressure further includes:

[0077] the chamber pressure of the gas turbine calculated according to the flow rate of the fuel oil; and

[0078] the nozzle pressure loss generated by the plurality of fuel nozzles.

[0079] According to the method in (3) above, by considering the pressure loss of the cavitation suppression section, the chamber pressure of the gas turbine, and the nozzle pressure loss, the second pressure (the downstream pressure of the flow control valve) used in the opening control of the flow control valve can be accurately obtained.

[0080] (4) According to the method in (3) above, in another method,

[0081] It further includes a water injection device for injecting water into at least a part of the plurality of fuel nozzles,

[0082] the chamber pressure is corrected according to the injection amount of the water injected by the water injection device,

[0083] the nozzle pressure loss is calculated according to the injection amount of the water and the flow rate of the fuel oil.

[0084] According to the method in (4) above, in the case of having a water injection device for reducing NOx discharged from the gas turbine by injecting water into at least a part of the fuel nozzles, the chamber pressure and the nozzle pressure loss used in the calculation of the second pressure are calculated according to the injection amount of the water injected by the water injection device. Thus, by considering the influence of water injection on the chamber pressure and the nozzle pressure loss, even in a device having a water injection device, the opening control of the flow adjustment valve can be performed with good accuracy.

[0085] (5) According to any one of the methods in (1) to (4) above, in another method,

[0086] The pump is arranged on the fuel oil supply pipeline connected to the fuel oil supply source,

[0087] The supply pressure regulating valve is provided on the return oil pipeline. The return oil pipeline branches from a position on the fuel oil supply pipeline that is downstream of the pump and upstream of the flow regulating valve, and is used to return at least a part of the fuel oil supplied by the pump to the fuel oil supply source.

[0088] According to the method in (5) above, a return oil pipeline for returning a part of the fuel oil to the fuel oil supply source is provided between the pump and the flow regulating valve in the fuel oil supply pipeline connected to the fuel oil supply source. A supply pressure regulating valve is provided on the return oil pipeline. By adjusting its opening degree, the supply pressure of the fuel oil from the pump, that is, the first pressure, can be controlled.

[0089] (6) According to any one of the methods in (1) to (5) above, in another method,

[0090] The opening degree of the supply pressure regulating valve is controlled so that the first pressure becomes constant.

[0091] According to the method in (6) above, by controlling the opening degree of the supply pressure regulating valve, the first pressure can be maintained constant.

[0092] (7) According to any one of the methods in (1) to (6) above, in another method,

[0093] The cavitation suppression part is integrally formed with the flow regulating valve.

[0094] According to the method in (7) above, by integrally forming the cavitation suppression part with the flow regulating valve, the above structure can be realized in a compact form.

[0095] (8) According to any one of the methods in (1) to (7) above, in another method,

[0096] The cavitation suppression part has a throttling structure with a flow path cross-sectional area variable corresponding to the flow rate of the fuel oil.

[0097] According to the method in (8) above, by providing a throttling structure with a flow path cross-sectional area variable corresponding to the flow rate of the fuel oil on the downstream side of the flow regulating valve, a cavitation suppression part that can effectively suppress cavitation even when the pressure difference between the upstream side and the downstream side of the flow regulating valve becomes large can be well realized.

[0098] Symbol Explanation

[0099] 1 - Gas turbine power plant, 2 - Compressor, 3 - Burner, 4 - Turbine, 5 - Fuel oil supply device, 6 - Generator, 7 - Rotating shaft, 10C - Common system, 10M1 - First main fuel supply system, 10M2 - Second main fuel supply system, 10P - Pilot fuel supply system, 11M1 - First main nozzle, 11M2 - Second main nozzle, 11P - Pilot nozzle, 12M1 - First main manifold, 12M2 - Second main manifold, 12P - Pilot manifold, 13M1 - First main flow control valve, 13M2 - Second main flow control valve, 13P - Pilot flow control valve, 14M1 - First main differential pressure control valve, 14M2 - Second main differential pressure control valve, 14P - Pilot differential pressure control valve, 15 - Fuel oil supply pipeline, 16 - Differential pressure sensor, 17 - Pressure sensor, 18 - Oil return pipeline, 19 - Supply pressure control valve, 20 - Pressure sensor, 21 - Pump, 22 - Temperature sensor, 23 - Oil return system, 30 - Cavitation suppression section, 31 - Fixed wall surface, 32 - Movable wall surface, 33 - Biasing member, 40 - Water injection device, 42 - Water supply source, 44 - Water supply pipeline, 50 - Control device, 52 - Supply pressure adjustment section.

Claims

1. A fuel oil supply device for supplying fuel oil to a burner of a gas turbine, the fuel oil supply device comprising: A pump for supplying the fuel oil; A supply pressure regulating valve disposed downstream of the pump for regulating the supply pressure of the fuel oil based on the pump; A plurality of flow regulating valves disposed downstream of the supply pressure regulating valve for respectively regulating the flow rate of the fuel oil supplied to a plurality of fuel nozzles of the burner; A plurality of cavitation suppression portions provided downstream of each of the plurality of flow regulating valves; and An opening degree control portion for controlling the opening degree of the flow regulating valve according to a first pressure of the fuel oil upstream of the flow regulating valve, a second pressure downstream of the flow regulating valve, and the flow rate of the fuel oil supplied to the fuel nozzle.

2. The fuel oil supply device according to claim 1, wherein The second pressure includes the pressure loss of the cavitation suppression portion calculated based on the flow rate of the fuel oil.

3. The fuel oil supply device according to claim 2, wherein The second pressure further includes: the chamber pressure of the gas turbine calculated based on the flow rate of the fuel oil; and the nozzle pressure loss generated by the plurality of fuel nozzles.

4. The fuel oil supply device according to claim 3, further comprising a water injection device for injecting water into at least a part of the plurality of fuel nozzles, The chamber pressure is corrected according to the injection amount of the water injected by the water injection device, The nozzle pressure loss is calculated according to the injection amount of the water and the flow rate of the fuel oil.

5. The fuel oil supply device according to claim 1 or 2, wherein The pump is provided on a fuel oil supply pipeline connected to a fuel oil supply source, The supply pressure regulating valve is provided on a return oil pipeline, and the return oil pipeline branches from a position on the fuel oil supply pipeline downstream of the pump and upstream of the flow regulating valve, and is used to return at least a part of the fuel oil supplied by the pump to the fuel oil supply source.

6. The fuel oil supply device according to claim 1 or 2, wherein The opening degree of the supply pressure regulating valve is controlled to make the first pressure constant.

7. The fuel oil supply device according to claim 1 or 2, wherein The cavitation suppression portion is integrally formed with the flow regulating valve.

8. The fuel oil supply device according to claim 1 or 2, wherein The cavitation suppression portion has a throttling structure with a flow path cross-sectional area variable corresponding to the flow rate of the fuel oil.

Images