fuel oil supply unit

Abstract

To prevent generation of cavitation by using a flow regulating valve even when the number of decompression stages of fuel oil is reduced along with reduction of the number of valves in a supply system of the fuel oil relative to a fuel nozzle.SOLUTION: This disclosure relates to a fuel oil supply system for supplying fuel oil to a combustor of a gas turbine. The fuel oil supply device includes: a pump for supplying the fuel oil; a supply pressure regulating valve disposed downstream of the pump to regulate supply pressure of the fuel oil by using the pump; and a plurality of flow regulating valves each disposed downstream of the supply pressure regulating valve to regulate a flow rate of the fuel oil to be supplied to each of a plurality of fuel nozzles of the combustor. A plurality of cavitation suppression sections are provided downstream of the plurality of the flow regulating valves. An opening of the flow regulating valve is controlled on the basis of first pressure of the fuel oil on the upstream side of the flow regulating valve, second pressure on the downstream side of the flow regulating valve and a flow rate of the fuel oil to be supplied to the fuel nozzle.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] In a gas turbine, the turbine is driven by combustion gas generated by combusting fuel in a combustor. In typical gas turbines, fuel gas operation that mainly uses fuel gas as fuel is performed; however, some gas turbines are also capable of oil-fired operation that uses fuel oil as fuel for backup purposes. A fuel oil supply device for supplying fuel oil, which is fuel for oil-firing, comprises, for example: a supply pressure regulating valve for regulating the supply pressure of fuel oil from a fuel oil supply source; and in each system corresponding to a plurality of fuel nozzles provided in a combustor, a flow rate 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 rate regulating valve. In this configuration, the flow rate regulating valve and the differential pressure regulating valve are provided for each supply system corresponding to each fuel nozzle, so the total number of regulating valves (the total number of supply pressure regulating valves, flow rate regulating valves, and differential pressure regulating valves) increases as a whole, which leads to high initial cost at the time of introduction.

[0003] As one approach to solving such a problem, sharing a plurality of differential pressure regulating valves provided in each supply system across all supply systems in the above configuration allows the number of section valves to be reduced. That is, by providing a pressure regulating valve shared by each supply system downstream of the supply pressure regulating valve, the number of regulating section valves included in the fuel oil supply device can be reduced compared to a case where a differential pressure regulating valve is provided for each supply system. For example, Patent Document 1 discloses a configuration example in which the number of regulating valves is reduced by reducing the number of differential pressure regulating valves arranged upstream of flow rate regulating valves for regulating the fuel flow rate to each fuel nozzle, although the configuration disclosed therein is for supplying fuel gas instead of fuel oil as fuel.

Prior Art Literature

Patent Literature

[0004] [Patent Document 1] International Publication No. 2013 / 105406 [Overview of the project] [Problems that the invention aims to solve]

[0005] As mentioned above, if the number of differential pressure control valves in the fuel oil supply system corresponding to each fuel nozzle is reduced, the number of pressure reduction stages by the control valves in each supply system will decrease (i.e., differential pressure control section Valves and flow control section In a configuration with a valve, the pressure reduction is two-stage, whereas reducing the differential pressure control valve allows for flow rate adjustment. section (This results in a one-stage pressure reduction by the valve.) As a result, the pressure difference between the upstream and downstream pressures of the flow control valve increases, and the flow control valve section Cavitation may occur in the fuel oil passing through the valve.

[0006] At least one embodiment of this disclosure has been made in view of the above circumstances and aims to provide a fuel oil supply device that can prevent cavitation with a flow control valve even when the number of pressure reduction stages for fuel oil decreases due to a reduction in the number of valves in the fuel oil supply system to each fuel nozzle. [Means for solving the problem]

[0007] A fuel oil supply device according to at least one embodiment of this disclosure solves the above problem, A fuel oil supply device for supplying fuel oil to the combustor of a gas turbine, A pump for supplying the aforementioned fuel oil, A supply pressure regulating valve is located downstream of the pump and adjusts the supply pressure of the fuel oil by the pump, The aforementioned supply pressure control section A plurality of flow control valves are arranged downstream of the valve and are used to adjust the flow rate of the fuel oil supplied to each of the plurality of fuel nozzles of the combustor, A plurality of cavitation suppression units are provided downstream of each of the plurality of flow control valves, Based on the first pressure of the fuel oil upstream of the flow control valve, the second pressure downstream of the flow control valve, and the flow rate of the fuel oil supplied to the fuel nozzle, the flow control valve section An opening degree control unit for controlling the opening degree of a valve, It is equipped with. [Effects of the Invention]

[0008] According to at least one embodiment of this disclosure, a fuel oil supply device is provided that can prevent cavitation from occurring with a flow control valve, even when the number of pressure reduction stages for fuel oil decreases due to a reduction in the number of valves in the fuel oil supply system to the fuel nozzle. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of a gas turbine power plant according to one embodiment. [Figure 2] Figure 1 is a schematic diagram of the fuel oil supply system. [Figure 3] Figure 2 is a schematic diagram of the fuel oil supply device according to the comparative example. [Figure 4] Figure 2 is a schematic diagram showing the cross-sectional structure of the cavitation suppression section. [Figure 5] Figure 2 is a block diagram showing the functional configuration of the control device for the fuel oil supply system. [Figure 6] This figure shows the calculation logic of the second pressure calculation unit in Figure 5. [Figure 7] Figure 7 shows the calculation logic for calculating the cabin pressure in Figure 6. [Figure 8] This graph shows the relationship between the first pressure, second pressure, cabin pressure, pressure loss in the cavitation suppression section, and nozzle pressure loss. [Modes for carrying out the invention]

[0010] Hereinafter, several embodiments of the present invention will be described with reference to the accompanying drawings. However, the configurations described as embodiments or shown in the drawings are not intended to limit the scope of the present invention thereto, and are merely illustrative examples.

[0011] FIG. 1 is a schematic configuration diagram of a gas turbine power plant 1 according to an embodiment. The gas turbine power plant 1 includes a compressor 2, a combustor 3, a tu - bine 4, a fuel oil supply device 5, and a generator 6.

[0012] The compressor 2 is configured to suck in air (atmospheric air) from the outside and generate compressed air. The compressed air generated by the compressor 2 is supplied to the combustor 3. The combustor 3 generates high-temperature combustion gas by mixing and combusting the compressed air supplied from the compressor 2 with fuel oil, which is fuel supplied from the fuel oil supply device 5. The turbine 4 is driven by being supplied with the high-temperature gas generated by the combustor 3, and outputs a rotational driving force from a rotating shaft 7. The rotational driving force output from the turbine 4 is transmitted to the generator 6 through the rotating shaft 7, whereby power generation is performed by the generator 6.

[0013] Next, the specific configuration of the fuel oil supply device 5 will be described with reference to FIG. 2. FIG. 2 is a schematic configuration diagram of the fuel oil supply device 5 of FIG. 1. The fuel oil supply device 5 is configured to supply fuel oil as fuel to the combustor 3. Note that the combustor 3 may mainly use other fuels such as fuel gas, and may be configured to use fuel oil supplied from the fuel oil supply device 5 as an alternative fuel.

[0014] The fuel oil supply device 5 is configured to be capable of supplying fuel oil to fuel nozzles provided in the combustor 3. The combustor 3 may be provided with a plurality of types of fuel nozzles. In the present embodiment, as the fuel nozzles, the combustor 3 includes a first main nozzle 11M1 and a second main nozzle 11M2 for premixed combustion aimed at reducing NOx, and a pilot nozzle 11P for diffusion combustion aimed at stabilizing combustion and the like.

[0015] Furthermore, in addition to these fuel nozzles, the combustor 3 may also be equipped with a top-hat nozzle, which is a fuel nozzle for premixed combustion aimed at further reducing NOx emissions. In this case, the fuel oil supply device 5 can also supply fuel oil to the top-hat nozzle. to The configuration of the combustor 3 equipped with a nozzle is not particularly limited and can be any known configuration, such as the configuration shown in Japanese Patent Application Publication No. 2007-77867.

[0016] The fuel oil supply system 5 includes a common system 10C, a first main fuel supply system 10M1, a second main fuel supply system 10M2, and a pilot to It is equipped with a fuel supply system 10P.

[0017] Common system 10C includes the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot to This system supplies fuel oil to the fuel supply system 10P and includes a fuel oil supply line 15. One end of the fuel oil supply line 15 is connected to a fuel oil source (not shown), which is the source of the fuel oil, and the other end branches off and connects 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 in the fuel oil supply line 15, and by operating the pump 21, fuel oil is supplied from the fuel oil source to the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P. to Fuel oil can be supplied to fuel supply system 10P.

[0018] Downstream of the fuel oil supply line 15 from the pump 21, a return line 18 branches off, which constitutes a return system 23 for returning at least a portion of the fuel oil flowing through the fuel oil supply line 15 back to the fuel oil supply source. A supply pressure regulating valve 19 is provided in the return line 18. sectionValve 19 is a valve whose opening degree can be controlled based on a control signal from the control device 50. By changing the flow rate of fuel oil returned to the fuel oil supply source via the 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 (first main fuel supply system 10M1, second main fuel supply system 10M2, and pilot fuel supply system 10P) can be adjusted (the first pressure P1 of the fuel oil upstream of the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P).

[0019] Furthermore, the common system 10C is equipped with 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.

[0020] The first main fuel supply system 10M1 is a system for supplying fuel oil to the first main nozzle 11M1. One end of the first main fuel supply system 10M1 is connected to the fuel oil supply line of the common system 10C. 15 It is connected to the first main nozzle 11M1, and the other end is connected to the first main nozzle 11M1 for supplying fuel oil to each of the first main nozzles Ni It is connected to the hold 12M1. Furthermore, the first main fuel supply system 10M1 is provided with a first main flow control valve 13M1 for controlling the flow rate of fuel oil supplied to the first main nozzle 11M1. The first main flow control valve 13M1 is a valve for adjusting the flow rate of fuel oil supplied to the first main nozzle 11M1. Ni The hold 12M1 is configured to distribute fuel oil supplied from the first main fuel supply system 10M1 to a plurality of first main nozzles 11M1.

[0021] The second main fuel supply system 10M2 is a system for supplying fuel oil to the second main nozzles 11M2. One end 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 is connected to the second main nozzles 11M2 for supplying fuel oil to each of the second main nozzles 11M2. NiIt is connected to the hold 12M2. Furthermore, the second main fuel supply system 10M2 is provided with a second main flow control valve 13M2 for controlling the flow rate of fuel oil supplied to the second main nozzle 11M2. The second main flow control valve 13M2 is a valve for adjusting the flow rate of fuel oil supplied to the second main nozzle 11M2. Ni The hold 12M2 is configured to distribute fuel oil supplied from the second main fuel supply system 10M2 to multiple second main nozzles 11M2.

[0022] pie B ッ to The fuel supply system 10P is a system that supplies fuel oil to the pilot nozzle 11P. to One end of the fuel supply system 10P is connected to the fuel oil supply line 15 of the common system 10C, and the other end supplies fuel to the pilot nozzle 11P. oil of Supplement It is connected to the pilot manifold 12P that supplies power. to The fuel supply system 10P has a pilot that controls the flow rate of fuel oil. to A flow control valve 13P is provided. to The flow control valve 13P is pilot to This is a valve that regulates the flow rate of fuel oil supplied to nozzle 11P. Ni Hold 12P supplies fuel oil from the pilot fuel supply system 10P to multiple pilots to This configuration is for distributing to nozzle 11P.

[0023] Furthermore, the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P are, So Each of the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P is equipped with a differential pressure sensor 16 for detecting the differential pressure ΔP between the first pressure P1, which is the upstream pressure, and the second pressure P2, which is the downstream pressure. Furthermore, downstream of the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P, the second pressure P 2Each is provided with a pressure sensor 17 for detecting the pressure.

[0024] The fuel oil supply device 5 also further includes a water injection device 40 for reducing NOx by injecting water into at least some of the fuel nozzles. In this embodiment, the water injection device 40 is configured to inject water into the first main nozzle 11M1 and the second main nozzle 11M2 of the fuel nozzles of the combustor 3. Specifically, the water injection device 40 has a water supply source 42 capable of supplying water and a water supply line 44 connected from the water supply source 42 to the first main nozzle 11M1 and the second main nozzle 11M2.

[0025] Here, Figure 3 is a schematic diagram of the fuel oil supply device 5' relating to the comparative example in Figure 2. The fuel oil supply device 5' includes a first main fuel supply system 10M1, a second main fuel supply system 10M2, and a pipe B ッ to Each of the fuel supply systems 10P is provided with a first main differential pressure control valve 14M1, a second main differential pressure control valve 14M2, and a pilot differential pressure control valve 14P upstream of the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P. The first main differential pressure control valve 14M1, the second main differential pressure control valve 14M2, and the pilot differential pressure control valve 14P are valves whose opening degree is controlled to adjust the differential pressure ΔP between the upstream pressure (first pressure P1) and the downstream pressure (second pressure P2) of each flow control valve to a predetermined value. In addition, in the comparative example shown in Figure 3, the components corresponding to the fuel oil supply device 5 shown in Figure 2 are denoted by the same reference numerals, and unless otherwise specified, redundant explanations are omitted as appropriate.

[0026] In this comparative example, since a flow control valve and a differential pressure control valve are provided for each fuel supply system corresponding to each fuel nozzle (first main fuel supply system 10M1, second main fuel supply system 10M2, and pilot fuel supply system 10P), the total number of control valves increases, resulting in higher initial costs during implementation. Therefore, in the configuration of the comparative example, by omitting the differential pressure control valves (first main differential pressure control valve 14M1, second main differential pressure control valve 14M2, and pilot differential pressure control valve 14P), the control valves are adjusted. section One possible solution is to reduce the number of valves. In this case, the number of pressure reduction stages by control valves in each supply system will decrease (that is, as shown in Figure 3, the differential pressure control valves in the first main fuel supply system 10M1, the second main fuel supply system 10M2, and the pilot fuel supply system 10P will each be reduced). section Valves and flow control section In a configuration where a valve is provided, there is a two-stage pressure reduction, whereas if the differential pressure control valve is reduced, the flow rate can be controlled. section (This results in a one-stage pressure reduction by the valve.) As a result, the differential pressure ΔP between the upstream pressure (first pressure P1) and the downstream pressure (second pressure P2) of the flow control valve increases, and the flow control valve section One problem is that cavitation is more likely to occur in the fuel oil as it passes through the valve.

[0027] To solve the problems in such comparative examples, the fuel oil supply device 5 according to this embodiment is provided with cavitation suppression units 30 downstream of each of the first main flow control valve 13M1, the second main flow control valve 13M2, and the pilot flow control valve 13P, as shown in Figure 2. The cavitation suppression unit 30 has, for example, a throttling structure in which the flow path cross-sectional area is variable in accordance with the flow rate of the fuel oil passing through it.

[0028] Figure 4 is a schematic diagram showing the cross-sectional structure of the cavitation suppression section 30 in Figure 2. In this configuration example, the flow path through which the fuel oil that has passed through each flow control valve passes is composed of a fixed wall surface 31 and a movable wall surface 32 elastically supported by the fixed wall surface 31. The movable wall surface 32 is elastically supported by a biasing member 33 such as a spring, so when the fuel oil flow rate is relatively low, the elastic force applied by the biasing member 33 causes the movable wall surface 32 to move towards the center of the flow path, making the flow path cross-sectional area relatively small. On the other hand, when the fuel oil flow rate is relatively high, the pressure received by the movable wall surface 32 resists the elastic force applied by the biasing member 33, causing the movable wall surface 32 to move away from the center of the flow path. side As the flow path moves toward the flow path, the cross-sectional area of ​​the flow path increases. Therefore, the fuel oil supply device 5 according to this embodiment, by including the aforementioned cavitation suppression unit 30, can effectively suppress cavitation even when the differential pressure between the first pressure P1 upstream of each flow control valve and the second pressure P2 downstream of each flow control valve becomes large, by varying the cross-sectional area of ​​the flow path according to the flow rate of fuel oil passing through each flow control valve (first main flow control valve 13M1, second main flow control valve 13M2, and pilot flow control valve 13P).

[0029] Furthermore, each cavitation suppression unit 30 may be integrally configured 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, the cavitation suppression unit 30 is configured with each flow control valve. amount By integrating it with the control valve, the above configuration can be realized in a compact form.

[0030] Next, the configuration of the control device 50 for controlling the fuel oil supply device 5 having the above configuration will be described. The control device 50 is composed of, for example, a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), and a computer-readable storage medium. A series of processes for realizing various functions are stored in the storage medium in the form of a program, for example. The CPU reads this program into the RAM and performs information processing and calculations to realize the various functions. The program may be pre-installed in the ROM or other storage medium, provided in a state where it is stored in a computer-readable storage medium, or distributed via wired or wireless communication. Computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, semiconductor memory, etc.

[0031] Figure 5 is a block diagram showing the functional configuration of the control device 50 of the fuel oil supply device shown in Figure 2. The control device 50 comprises a supply pressure adjustment unit 52, a second pressure calculation unit 54, and an opening degree control unit 56.

[0032] The supply pressure adjustment unit 52 is configured to adjust the supply pressure of fuel oil supplied by the common system 10C. Specifically, the supply pressure adjustment unit 52 controls the supply pressure of fuel oil supplied by the pump 21 and the opening degree of the supply pressure adjustment valve 19 so that the first pressure P1 detected by the pressure sensor 20 becomes a predetermined value, thereby adjusting the supply pressure from the common system 10C (approximately equal to the first pressure P1) to a predetermined value.

[0033] The second pressure calculation unit 54 is configured to calculate the second pressure P2, which is the downstream pressure of each flow control valve (first main flow control valve 13M1, second main flow control valve 13M2, and pilot flow control valve 13P). Here, Figure 6 is a diagram showing the calculation logic of the second pressure calculation unit 54 in Figure 5, Figure 7 is a diagram showing the calculation logic for calculating the cabin pressure Pc in Figure 6, and Figure 8 is a graph showing the relationship between the first pressure P1, the second pressure P2, the cabin pressure Pc, the pressure loss Pk of the cavitation suppression unit 30, and the nozzle pressure loss Pn.

[0034] As shown in Figure 6, the second pressure P2, which is the downstream pressure of each flow control valve (first main flow control valve 13M1, second main flow control valve 13M2, and pilot flow control valve 13P), is calculated by subtracting the cabin pressure Pc, the pressure loss Pk of the cavitation suppression unit 30, and the nozzle pressure loss Pn from the first pressure P1, which is the upstream pressure. Here, the first pressure P1 is adjusted by the supply pressure adjustment unit 52 controlling the pump 21 and the supply pressure adjustment valve 19 so that the detected value of the pressure sensor 20 becomes a predetermined value (Figure 8 shows that the first pressure P1 is obtained by subtracting the differential pressure ΔPs of the supply pressure adjustment valve 19 from the supply pressure P0 from the pump 21).

[0035] Furthermore, as shown in Figure 7, the cabin pressure Pc is obtained by multiplying the result of inputting the fuel flow command, calculated based on the supply and demand signal for the gas turbine power plant 1, into function FX3, with the result of inputting the amount of water injected by the water injection device 40 into function FX4.

[0036] Furthermore, the pressure loss Pk of the cavitation suppression unit 30 is obtained as a result of inputting the fuel oil flow rate into the function FX1, as shown in Figure 6. Function FX1 is pre-defined as a function that defines the correlation between the fuel oil flow rate and the pressure loss Pk of the cavitation suppression unit 30. The fuel oil flow rate is obtained by dividing the fuel flow rate command by the fuel density.

[0037] Furthermore, the nozzle pressure loss Pn is obtained by inputting the result of adding the aforementioned fuel oil flow rate and the amount of water injected by the water injection device 40 into the function FX2. Function FX2 is pre-defined as a function that defines the correlation between the sum of the fuel oil flow rate and the amount of water injected and the nozzle pressure loss Pn.

[0038] The cabin pressure Pc, the pressure loss Pk of the cavitation suppression unit 30, and the nozzle pressure loss Pn, obtained in this way, are subtracted from the first pressure P1, which is the upstream pressure of each flow control valve, to obtain the second pressure P2, which is the downstream pressure of each flow control valve.

[0039] Returning to Figure 5, the opening degree control unit 56 is configured to control the opening degree of each flow control valve (first main flow control valve 13M1, second main flow control valve 13M2, and pilot flow control valve 13P). degree The first pressure P1 of the fuel oil upstream of the flow control valve, the second pressure P2 downstream of the flow control valve, and the flow rate of fuel oil supplied to each fuel nozzle are used to calculate the pressure. The first pressure P1 is uniquely determined by the supply pressure adjustment unit 52 adjusting the detected value of the pressure sensor 20 to a predetermined value, as described above. The second pressure P2 is calculated using the result of the second pressure calculation unit 54 described above.

[0040] In this manner, the opening control unit 56 controls the opening degree of each flow control valve (first main flow control valve 13M1, second main flow control valve 13M2, and pilot flow control valve 13P) based on the second pressure P2, but the second pressure P2 used is calculated taking into account the pressure loss Pk of the cavitation suppression unit 30. As a result, even when a cavitation suppression unit 30 is provided downstream of each flow control valve to suppress cavitation, the opening degree of each flow control valve can be controlled based on a highly accurate second pressure P2.

[0041] Furthermore, the second pressure P2 used for controlling the opening degree of each flow control valve is calculated based on the cabin pressure Pc and nozzle pressure loss Pn, which are determined considering the amount of water injected by the water injection device 40, as described above. This allows for accurate flow control in the fuel oil supply device 5 equipped with the water injection device 40, by determining the cabin pressure Pc and nozzle pressure loss Pn while considering the effects of water injection. section The valve opening degree can be controlled.

[0042] As described above, according to the above embodiment, even when the number of pressure reduction stages for fuel oil decreases due to a reduction in the number of valves in the fuel oil supply system to the fuel nozzle, a fuel oil supply device 5 is provided that can prevent cavitation from occurring in each flow control valve.

[0043] Furthermore, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, without departing from the spirit of this disclosure, and the above-described embodiments may also be combined as appropriate.

[0044] The contents described in each of the above embodiments can be understood, for example, as follows:

[0045] (1) A fuel oil supply device according to one embodiment is: A fuel oil supply device for supplying fuel oil to the combustor of a gas turbine, A pump for supplying the aforementioned fuel oil, A supply pressure regulating valve is located downstream of the pump and adjusts the supply pressure of the fuel oil by the pump, The aforementioned supply pressure control section A plurality of flow control valves are arranged downstream of the valve and are used to adjust the flow rate of the fuel oil supplied to each of the plurality of fuel nozzles of the combustor, A plurality of cavitation suppression units are provided downstream of each of the plurality of flow control valves, Based on the first pressure of the fuel oil upstream of the flow control valve, the second pressure downstream of the flow control valve, and the flow rate of the fuel oil supplied to the fuel nozzle, the flow control valve section An opening degree control unit for controlling the opening degree of a valve, It is equipped with.

[0046] According to the embodiment of (1) above, a cavitation suppression unit is provided downstream of the flow control valve, which is provided in each supply system for supplying fuel oil to each fuel nozzle of the combustor. As a result, even when the differential pressure on the upstream and downstream sides of the flow control valve increases due to the reduction of differential pressure control valves in each supply system, cavitation can be effectively prevented from occurring in the fuel oil that has passed through the flow control valve.

[0047] (2) In other embodiments, in the embodiment of (1) above, The second pressure includes the pressure loss of the cavitation suppression unit calculated based on the flow rate of the fuel oil.

[0048] According to the embodiment of (2) above, the second pressure used to control the opening degree of the flow control valve includes the pressure loss in the cavitation suppression section. By controlling the opening degree of the flow control valve while taking into account the effect of providing the cavitation suppression section downstream of the flow control valve in this way, it is possible to prevent the occurrence of cavitation while controlling the flow rate of fuel oil supplied to each fuel nozzle with good accuracy.

[0049] (3) In other embodiments, in the embodiment of (2) above, The second pressure is, The cabin pressure of the gas turbine, calculated based on the flow rate of the fuel oil, Nozzle pressure loss due to the plurality of fuel nozzles, It also includes.

[0050] According to the embodiment of (3) above, by considering the pressure loss of the cavitation suppression section, the gas turbine cabin pressure, and the nozzle pressure loss, the second pressure (downstream pressure of the flow control valve) used for controlling the opening of the flow control valve can be determined with high accuracy.

[0051] (4) In other embodiments, in the embodiment of (3) above, The system further comprises a water injection device for injecting water into at least some of the plurality of fuel nozzles, The cabin pressure is corrected based on the amount of water injected by the water injection device. The nozzle pressure loss is calculated based on the amount of water injected and the flow rate of the fuel oil.

[0052] According to the embodiment of (4) above, when a water injection device is provided to reduce NOx emitted from the gas turbine by injecting water into at least some of the fuel nozzles, the cabin pressure and nozzle pressure drop used in calculating the second pressure are calculated based on the amount of water injected by the water injection device. This allows for accurate flow rate adjustment even in devices equipped with a water injection device by considering the effect of water injection on cabin pressure and nozzle pressure drop. sectionThe valve opening degree can be controlled.

[0053] (5) In other embodiments, in any one embodiment of (1) to (4) above, The pump is installed in a fuel oil supply line connected to a fuel oil supply source. The supply pressure regulating valve is located downstream of the pump in the fuel oil supply line, and the flow rate regulating valve section It is provided in a return line that branches off from the upstream side of the valve and returns at least a portion of the fuel oil supplied by the pump back to the fuel oil supply source.

[0054] According to the embodiment of (5) above, a return line is provided between the pump and the flow control valve in the fuel oil supply line connected to the fuel oil supply source to return a portion of the fuel oil to the fuel oil supply source. A supply pressure control valve is provided in the return line, and by adjusting its opening degree, the first pressure, which is the fuel oil supply pressure from the pump, can be controlled.

[0055] (6) In other embodiments, in any one embodiment of (1) to (5) above, The opening of the supply pressure control valve is controlled so that the first pressure remains constant.

[0056] According to the embodiment of (6) above, the first pressure can be kept constant by controlling the opening degree of the supply pressure control valve.

[0057] (7) In other embodiments, in any one embodiment of (1) to (6) above, The cavitation suppression unit controls the flow rate section It is integrated with the valve.

[0058] According to the embodiment of (7) above, the cavitation suppression unit flows amount By integrating it with the control valve, the above configuration can be realized in a compact form.

[0059] (8) In other embodiments, in any one embodiment of (1) to (7) above, The cavitation suppression unit has a throttling structure in which the flow path cross-sectional area is variable in accordance with the flow rate of the fuel oil.

[0060] According to the embodiment of (8) above, the flow of fuel oil downstream of the flow control valve amount By providing a throttling structure with a variable flow path cross-sectional area in response to this, a cavitation suppression unit can be suitably realized that can effectively suppress cavitation even when the differential pressure on the upstream and downstream sides of the flow control valve becomes large. [Explanation of symbols]

[0061] 1. Gas turbine power plant 2 Compressor 3 Combustor 4 Turbines 5 Fuel oil supply device 6 Generators 7 Rotation axis 10C common system 10M1 Main Fuel Supply System No. 1 10M2 Second Main Fuel Supply System 10P Pilot to fuel supply system 11M1 First Main Nozzle 11M2 Second Main Nozzle 11P Pilot Nozzle 12M1 1st Main Match Ni hold 12M2 2nd Main Match Ni hold 12P Pilot Ni hold 13M1 First Main Flow Control Valve 13M2 Second Main Flow Control Valve 13P Pilot flow control valve 14M1 No. 1 Main Differential Pressure Control Valve 14M2 Second Main Differential Pressure Control Valve 14P Pilot Differential Pressure Control Valve 15 Fuel oil supply line 16 Differential pressure sensor 17 Pressure Sensor 18 Return Line 19. Supply pressure regulating valve 20 Pressure Sensors 21 pumps 22 Temperature Sensor 23 Return System 30 Cavitation suppression section 31 Fixed wall surface 32 Movable wall 33. Biasing member 40 Water injection device 42 Water source 44 Water supply lines 50 Control device 52 Supply pressure adjustment unit

Claims

1. A fuel oil supply device for supplying fuel oil to the combustor of a gas turbine, A pump for supplying the aforementioned fuel oil, A supply pressure regulating valve is located downstream of the pump and adjusts the supply pressure of the fuel oil by the pump, A plurality of flow control valves are arranged downstream of the supply pressure control valve and for adjusting the flow rate of the fuel oil supplied to each of the plurality of fuel nozzles of the combustor, A plurality of cavitation suppression units are provided downstream of each of the plurality of flow control valves, An opening control unit 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, Equipped with, The fuel oil supply device includes a second pressure which includes the pressure loss of the cavitation suppression section calculated based on the flow rate of the fuel oil.

2. The second pressure is, The cabin pressure of the gas turbine, calculated based on the flow rate of the fuel oil, Nozzle pressure loss due to the plurality of fuel nozzles, The fuel oil supply device according to claim 1, further comprising:

3. The system further comprises a water injection device for injecting water into at least some of the plurality of fuel nozzles, The cabin pressure is corrected based on the amount of water injected by the water injection device. The fuel oil supply device according to claim 2, wherein the nozzle pressure loss is calculated based on the amount of water injected and the flow rate of the fuel oil.

4. The pump is installed in a fuel oil supply line connected to a fuel oil supply source. The fuel oil supply device according to claim 1 or 2, wherein the supply pressure regulating valve is provided in a return line that branches off from the fuel oil supply line downstream of the pump and upstream of the flow rate regulating valve, and returns at least a portion of the fuel oil supplied by the pump back to the fuel oil supply source.

5. The fuel oil supply device according to claim 1 or 2, wherein the opening of the supply pressure control valve is controlled so that the first pressure remains constant.

6. The fuel oil supply device according to claim 1 or 2, wherein the cavitation suppression unit is integrally configured with the flow rate control valve.

7. The fuel oil supply device according to claim 1 or 2, wherein the cavitation suppression unit has a throttling structure in which the flow path cross-sectional area is variable in accordance with the flow rate of the fuel oil.

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