Power plant governor execution unit

Abstract

The present invention relates to an execution unit for a governor of a power plant, comprising a hydraulic cylinder and a hydraulic system. The hydraulic system includes an oil tank and an oil pump. The hydraulic cylinder includes a plurality of hydraulic cylinder units arranged in parallel, each of which includes a unit cylinder block and a unit piston rod assembled in the corresponding unit cylinder block for guided movement. The hydraulic cylinder further includes a power output rod connected to the power output end of each unit piston rod. The piston of the unit piston rod divides the unit cylinder block into a first piston chamber and a second piston chamber. The oil pump is connected to the first piston chamber and the second piston chamber of each hydraulic cylinder unit via a hydraulic oil passage. A control valve unit is provided in the hydraulic oil passage, and the control valve unit has multiple control modes, and in each control mode, the hydraulic oil passage supplies oil to a different number of hydraulic cylinder units. The present invention provides an execution unit for a governor of a power plant, which can adjust the output force value by changing the pressure-receiving area of ​​the piston.

Description

[Technical Field]

[0001] The present invention relates to an executive component associated with a speed regulator in a power plant, and in particular to an executive unit for a power plant governor. [Background technology]

[0002] In hydroelectric power plants, the amount of water flowing into the generator is controlled by opening and closing guide vanes. The opening and closing of the guide vanes is controlled by an execution unit, which mainly includes a hydraulic cylinder and a hydraulic device. The hydraulic device includes an oil tank, an oil pump, and a hydraulic oil passage connected between the oil pump and the hydraulic cylinder, with a flow control valve installed in the hydraulic oil passage.

[0003] During operation, the magnitude and operating speed of a hydraulic cylinder's output force are controlled by adjusting the flow control valve or the power of the pump station. This control method has the following problems. The cylinder thrust of a hydraulic cylinder is calculated as F = P × S, where S is the piston cross-sectional area of ​​the hydraulic cylinder, a fixed value. P is the hydraulic pressure inside the hydraulic cylinder, a variable value. The hydraulic pressure can be adjusted by changing the power of the pump station and the opening of the flow control valve. However, traditional hydraulic control methods rely on sudden starts, stops, speed changes, or direction changes of the hydraulic system, or the sudden closure of the flow control valve or sudden stopping of operation. As a result, extremely high peak pressures are generated within the system due to the inertia of the flowing liquid and moving parts. This phenomenon is called hydraulic shock. Hydraulic shock can cause serious damage to the hydraulic system and can also lead to certain errors in hydraulic control. Especially during the guide vane adjustment process in hydroelectric power plants, the guide vanes are constantly under load, and the load is unstable. This generates elastic reaction forces in the corresponding hydraulic equipment. This reaction force acts on the driving hydraulic pressure and may have a certain effect on the magnitude of the thrust force of the hydraulic cylinder and speed adjustment. Summary of the Invention

[0004] SUMMARY OF THE INVENTION An object of the present invention is to provide an execution unit for a governor of a power plant that can adjust the output value by changing the pressure-receiving area of ​​the piston.

[0005] In order to solve the above problems, the power plant governor execution unit of the present invention has the following technical configuration. An execution unit for a governor of a power plant includes a hydraulic cylinder and a hydraulic system. The hydraulic system includes an oil tank and an oil pump. The hydraulic cylinder includes multiple hydraulic cylinder units arranged in parallel, each of which includes a unit cylinder block and a unit piston rod assembled in the corresponding unit cylinder block so as to be guided and movable. The hydraulic cylinder further includes a power output rod connected to the power output end of each unit piston rod. The piston of the unit piston rod divides the unit cylinder block into a first piston chamber and a second piston chamber. The oil pump is connected to the first piston chamber and the second piston chamber of each hydraulic cylinder unit via hydraulic oil passages, and a control valve unit is provided in the hydraulic oil passages. The control valve unit has multiple control modes, and in each control mode, the hydraulic oil passages supply oil to a different number of hydraulic cylinder units.

[0006] Furthermore, there are a total of 19 hydraulic cylinder units, of which 18 hydraulic cylinder units form two concentric annular rows, with the inner annular row including six hydraulic cylinder units spaced evenly around the circumference and the outer annular row including 12 hydraulic cylinder units spaced evenly around the circumference, and the remaining hydraulic cylinder unit being located at the center of the hydraulic cylinder units in the inner annular row.

[0007] Furthermore, the hydraulic cylinder units in the outer annular row are referred to in order along the circumferential direction as hydraulic cylinder unit 1, hydraulic cylinder unit 2, hydraulic cylinder unit 3, hydraulic cylinder unit 4, hydraulic cylinder unit 5, hydraulic cylinder unit 6, hydraulic cylinder unit 7, hydraulic cylinder unit 8, hydraulic cylinder unit 9, hydraulic cylinder unit 10, hydraulic cylinder unit 11, and hydraulic cylinder unit 12. The hydraulic cylinder units in the inner annular row are referred to in order along the circumferential direction as hydraulic cylinder unit 13, hydraulic cylinder unit 14, hydraulic cylinder unit 15, hydraulic cylinder unit 16, hydraulic cylinder unit 17, and hydraulic cylinder unit 18. The hydraulic cylinder unit at the center is referred to as hydraulic cylinder unit 19. The control valve unit includes five valve unit modules, one of which controls hydraulic cylinder units 1, 3, 5, 7, 9 and 11 to supply oil simultaneously, one of which controls hydraulic cylinder units 2, 4, 6, 8, 10 and 12 to supply oil simultaneously, one of which controls hydraulic cylinder units 13, 15 and 17 to supply oil simultaneously, one of which controls hydraulic cylinder units 14, 16 and 18 to supply oil simultaneously, and one of which controls hydraulic cylinder unit 19 to supply oil.

[0008] The hydraulic cylinder further includes an outer cylinder block, and a front cylinder block end plate and a rear cylinder block end plate are provided at both ends of the outer cylinder block. The rear end of the unit cylinder block of each hydraulic cylinder unit is fixed to the rear cylinder block end plate, and the power output rod has a small diameter segment that is fitted and guided movably in the front cylinder block end plate and a large diameter segment that is fitted and guided movably in the inner cavity of the outer cylinder block.

[0009] Furthermore, the large diameter segment is provided with communication holes that connect the internal cavities of the outer cylinder blocks on both the front and rear sides of the large diameter segment, and the front end of the unit cylinder block of each hydraulic cylinder unit is provided with a front end oil port connected to the second piston chamber, and the rear end of the unit cylinder block of each hydraulic cylinder unit is provided with a rear end oil port connected to the first piston chamber, and each unit cylinder block is provided with a cylinder block oil path whose front end is connected to the front end oil port.

[0010] Furthermore, the rear cylinder block end plate is provided with an end plate first oil port that connects the corresponding rear end oil port with the control valve unit, and an end plate second oil port that connects the rear end of the cylinder block oil path with the control valve unit.

[0011] The beneficial effects of the present invention are as follows: The multiple hydraulic cylinder units in the present invention output power to the outside through the same power output rod, and the control valve unit can supply oil to the corresponding number of hydraulic cylinder units according to the demand for output force. This allows the force-receiving area of ​​the pistons of the entire hydraulic cylinder to be varied, and ultimately the output value of the hydraulic cylinder to be adjusted. This eliminates the need to frequently change the rotation speed of the oil pump or the opening degree of the corresponding valve, and stabilizes the oil pressure in the hydraulic oil passage, reducing the occurrence of hydraulic shock. [Brief explanation of the drawings]

[0012] These and other objects, features, and advantages of exemplary embodiments of the present disclosure will be readily understood by reading the following detailed description in conjunction with the drawings in which several embodiments of the present disclosure are illustrated by way of example, and not by way of limitation, and in which like or corresponding reference numerals indicate like or corresponding parts. [Figure 1] 1 is a structural schematic diagram of an embodiment of an execution unit for a governor of a power plant in the present invention; FIG. [Figure 2] FIG. 2 is a structural schematic diagram of the hydraulic cylinder in FIG. 1. [Figure 3]FIG. 2 is a schematic diagram showing the distribution of hydraulic cylinder units in FIG. 1. [Figure 4] FIG. 2 is a control schematic diagram of a control valve unit and each hydraulic unit according to the present invention. [Figure 5] FIG. 2 is a schematic diagram showing a state in which a unit piston rod of the hydraulic cylinder unit in FIG. 1 is extended. DETAILED DESCRIPTION OF THE INVENTION

[0013] To facilitate understanding of the present invention, the present invention will be described in more detail below with reference to the drawings and specific embodiments. Preferred embodiments of the present invention are shown in the drawings. The present invention is not limited to the embodiments described herein, but can be implemented in many different forms. These embodiments are shown to provide a clearer and more comprehensive understanding of the contents of the present invention.

[0014] It should be noted that unless otherwise defined, the present invention uses all technical and scientific terms and has the same meaning as commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are for describing specific embodiments and are not intended to limit the present invention.

[0015] An embodiment of an execution unit for a power plant governor of the present invention is shown in Figures 1 to 5. It includes a pump station 20 and a hydraulic cylinder 5, the pump station 20 includes a hydraulic system 25, the hydraulic system 25 includes an oil tank 1 and an oil pump 2, and the oil pump 2 is installed on the oil tank 1.

[0016] The hydraulic cylinder 5 includes a plurality of hydraulic cylinder units 6 arranged in parallel with an outer cylinder block 19. In the present invention, there are 19 hydraulic cylinder units 6, and the axes of all hydraulic cylinder units 6 extend along the front-to-rear direction. A front cylinder block end plate 15 and a rear cylinder block end plate 9 are fixed to the front and rear ends of the outer cylinder block 19, respectively. The outer cylinder block 19, the front cylinder block end plate 15, and the rear cylinder block end plate 9 surround a hollow cavity 26. Each hydraulic cylinder unit 6 includes a unit cylinder block 12 and a unit piston rod 7 assembled to the unit cylinder block 12 so as to be guided and movable in the front-to-rear direction, and each hydraulic cylinder unit 6 is installed within the hollow cavity 26.

[0017] In this embodiment, the rear ends of the unit cylinder blocks 12 of each hydraulic cylinder unit 6 are fixed to the rear cylinder block end plate 9, and the unit cylinder blocks 12 of each hydraulic cylinder unit 6 have an integrally molded structure. The pistons of the unit piston rods 7 divide the unit cylinder block 12 into a first piston chamber 8 and a second piston chamber 27, with the second piston chamber 27 located in front of the first piston chamber 8. The hydraulic cylinder 5 further includes a power output rod 10 connected to the power output end of each unit piston rod 7. The power output rod 10 includes a small-diameter segment 16 that is fitted into the front cylinder block end plate 15 so as to be guided and movable, and a large-diameter segment 17 that is fitted into the internal cavity of the outer cylinder block 19 so as to be guided and movable. In this embodiment, the large-diameter segment 17 and the small-diameter segment 16 are referred to as the large-diameter segment 17 because the outer diameter of the large-diameter segment 17 is larger than that of the small-diameter segment 16, relatively speaking.

[0018] The large diameter segment 17 is fixed to the front end of the unit piston rod 7 of each hydraulic cylinder unit 6, and the large diameter segment 17 has communication holes 18 that connect the internal cavities of the outer cylinder blocks 19 on both the front and rear sides of the large diameter segment 17. In this embodiment, multiple communication holes 18 are provided, and the multiple communication holes 18 are arranged circumferentially at intervals around the outer periphery of the large diameter segment 17.

[0019] The oil pump 2 is connected to the first piston chamber 8 and the second piston chamber 27 of each hydraulic cylinder unit 6 by a hydraulic oil passage 4, and a control valve unit 3 is installed in the hydraulic oil passage 4. The control valve unit 3 has a plurality of control modes, and in each control mode, the hydraulic oil passage 4 supplies oil to a different number of hydraulic cylinder units 6. Specifically, a front-end oil port 14 connected to the second piston chamber 27 is provided at the front end of the unit cylinder block 12 of each hydraulic cylinder unit 6. A cylinder block protrusion 24 is provided on the outer periphery of the unit cylinder block 12. A cylinder block oil path 22 extending along the front-to-rear direction is provided within the cylinder block protrusion 24, and the front end of the cylinder block oil path 22 communicates with the front-end oil port 14.

[0020] A rear-end oil port 11 connecting to the corresponding first piston chamber 8 is provided at the rear end of the unit cylinder block 12 of each hydraulic cylinder unit 6. A first end plate oil port 13 connecting the corresponding rear-end oil port 11 to the control valve unit 3 is provided at the rear cylinder block end plate 9. A second end plate oil port 23 connecting the rear end of the corresponding cylinder block oil path 22 to the control valve unit 3 is further provided at the rear cylinder block end plate 9. Reference numeral 21 in the drawing denotes a controller 21 that controls the operation of the control valve unit 3.

[0021] In this embodiment, 18 of the 19 hydraulic cylinder units 6 form two concentric annular rows. The inner annular row includes six hydraulic cylinder units 6 spaced evenly along the circumferential direction. The outer annular row includes 12 hydraulic cylinder units 6 spaced evenly along the circumferential direction. The remaining hydraulic cylinder unit 6 is located at the center of the hydraulic cylinder units 6 in the inner annular row. In the hydraulic cylinder units 6 on the same circle, the axes of all the hydraulic cylinder units 6 are located on a single circle, and the cylinder block protrusions 24 are located outside the circle. This configuration reduces the radial space occupied by all the hydraulic cylinder units 6, while also contributing to reducing the circumferential space occupied by the hydraulic cylinder units 6 in this ring.

[0022] The hydraulic cylinder units 6 in the outer annular row are referred to in order along the circumferential direction as hydraulic cylinder unit 1 6, hydraulic cylinder unit 2 6, hydraulic cylinder unit 3 6, hydraulic cylinder unit 4 6, hydraulic cylinder unit 5 6, hydraulic cylinder unit 6, hydraulic cylinder unit 7 6, hydraulic cylinder unit 8 6, hydraulic cylinder unit 9 6, hydraulic cylinder unit 10 6, hydraulic cylinder unit 11 6, and hydraulic cylinder unit 12 6. The hydraulic cylinder units 6 in the inner annular row are referred to in order along the circumferential direction as hydraulic cylinder unit 13 6, hydraulic cylinder unit 14 6, hydraulic cylinder unit 15 6, hydraulic cylinder unit 16, hydraulic cylinder unit 17 6, and hydraulic cylinder unit 18 6. The hydraulic cylinder unit 6 at the center is referred to as hydraulic cylinder unit 19 6. The control valve unit 3 includes five valve unit modules 28, one of which controls the first, third, fifth, seventh, nineth, and eleventh hydraulic cylinder units 6 to supply oil simultaneously, one of which controls the second, fourth, sixth, eighth, tenth, and twelfth hydraulic cylinder units 6 to supply oil simultaneously, one of which controls the thirteenth, fifteenth, and seventeenth hydraulic cylinder units 6 to supply oil simultaneously, one of which controls the fourteenth, sixteenth, and eighteenth hydraulic cylinder units 6 to supply oil simultaneously, and one of which controls the nineteenth hydraulic cylinder unit 6 to supply oil.

[0023] During operation, the number of operating hydraulic cylinder units 6 can be selected according to the demand for output force of the hydraulic cylinders 5. For example, if one hydraulic cylinder unit 6 can meet the demand for output force of the entire hydraulic cylinders 5, the corresponding valve unit module 28 of the control valve unit 3 controls the pump station 20 to supply oil to the first piston chamber 8 of the 19th hydraulic cylinder unit 6, and the oil in the second piston chamber 27 of the 19th hydraulic cylinder unit 6 is returned to the oil tank 1 via the cylinder block oil path 22 and the control valve unit 3. The first piston chambers 8 of the other hydraulic cylinder units 6 are connected to the bottom of the oil tank 1 by the control valve unit 3. That is, when the power output rod 10 is driven by one of the hydraulic cylinder units 6 to move forward, the first piston chambers 8 of the other hydraulic cylinder units 6 are in an oil-absorbing state, and pressureless oil in the oil tank 1 is drawn into the corresponding first piston chamber 8.

[0024] That is, one hydraulic cylinder unit 6 has an operating state and a standby state. In the operating state, when it is necessary to extend the unit piston rod 7, oil is pressurized and supplied to the first piston chamber 8 by the control valve unit 3, and the hydraulic oil in the second piston chamber 27 is returned to the oil tank 1 via the cylinder block oil path 22 and the control valve unit 3. On the other hand, when it is necessary to extend the unit piston rod 7, oil is pressurized and supplied to the second piston chamber 27 by the control valve unit 3 and the cylinder block oil path 22, and the hydraulic oil in the first piston chamber 8 is returned to the oil tank 1 via the control valve unit 3. In the standby state, when the unit piston rod 7 extends together with the power output rod 10, the first piston chamber 8 is connected to the oil tank 1 via the control valve unit 3, and the second piston chamber 27 is connected to the oil tank 1 via the cylinder block oil path 22 and the control valve unit 3, and the hydraulic oil in the second piston chamber 27 is returned to the oil tank 1, while hydraulic oil is sucked into the first piston chamber 8. When the unit piston rod 7 contracts together with the power output rod 10, the hydraulic oil in the first piston chamber 8 is returned to the oil tank 1, and the second piston chamber 27 draws the hydraulic oil through the cylinder block oil path 22 and the control valve unit 3.

[0025] Similarly, three hydraulic cylinder units 6 may be selected to simultaneously output power to the outside, four hydraulic cylinder units 6 may simultaneously output power to the outside, six hydraulic cylinder units 6 may simultaneously output power to the outside, seven hydraulic cylinder units 6 may simultaneously output power to the outside, nine hydraulic cylinder units 6 may simultaneously output power to the outside, eighteen hydraulic cylinder units 6 may simultaneously output power to the outside, or nineteen hydraulic cylinder units 6 may simultaneously output power to the outside. When a different number of hydraulic cylinder units 6 output power to the outside, the pressure-receiving cross-sectional areas of the unit piston rods 7 that receive the hydraulic pressure are different. Therefore, even when the hydraulic pressures are consistent, the overall force output to the outside of the hydraulic cylinders 5 can be changed by changing the number of operating hydraulic cylinder units 6. In this embodiment, the hydraulic cross-sectional area received by each unit piston rod 7 is the same, but in other embodiments of the present invention, the hydraulic cross-sectional areas received by each unit piston rod 7 may be different. The special layout of the hydraulic cylinder units 6 allows the force-receiving direction of the power output rod 10 to always coincide with the axis of the power output rod 10 regardless of the operating mode.

[0026] It should be noted that the above-described embodiments are merely examples for explaining the technical concept of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail based on the above-described embodiments, it should be understood that those skilled in the art can appropriately modify the technical means described in each of the above-described embodiments or replace some of the technical features with equivalent means. However, these modifications or substitutions are understood to be included within the technical scope of the present invention as long as they do not deviate from the corresponding technical concept and scope. [Explanation of symbols]

[0027] 1 oil tank 2 oil pumps 3 Control valve unit 4 Hydraulic oil passages 5 hydraulic cylinders 6 Hydraulic Cylinder Unit 7 unit piston rod 8. First piston chamber 9 Rear cylinder block end plate 10 Power Output Rod 11 Rear oil port 12 unit cylinder block 13 End plate first oil port 14 Front end oil port 15 Front cylinder block end plate 16 small diameter segments 17 Large diameter segments 18 Communication hole 19 Outer cylinder block 20. Pump Station 21 Controller 22 Cylinder block oil path 23 End plate second oil port 24 Cylinder block protrusion 25 Hydraulic System 26 Hollow Cavity 27 Second piston chamber 28 Valve Unit Module

Claims

1. An execution unit for a power plant governor, comprising: a hydraulic cylinder and a hydraulic system, the hydraulic system including an oil tank and an oil pump; the hydraulic cylinder includes a plurality of hydraulic cylinder units arranged in parallel, each hydraulic cylinder unit having a unit cylinder block and a unit piston rod assembled in the corresponding unit cylinder block so as to be guided and movable, the hydraulic cylinder further having one power output rod connected to the power output end of each unit piston rod, the piston of the unit piston rod divides the unit cylinder block into a first piston chamber and a second piston chamber, the oil pump is connected to the first piston chamber and the second piston chamber of each hydraulic cylinder unit via a hydraulic oil passage, a control valve unit is provided in the hydraulic oil passage, the control valve unit has a plurality of control modes, and in each control mode the hydraulic oil passage supplies oil to a different number of hydraulic cylinder units.

2. 2. The power plant governor execution unit according to claim 1, characterized in that it has a total of 19 hydraulic cylinder units, of which 18 hydraulic cylinder units form two concentric annular rows, the inner annular row including 6 hydraulic cylinder units equally spaced apart along the circumferential direction, the outer annular row including 12 hydraulic cylinder units equally spaced apart along the circumferential direction, and the remaining one hydraulic cylinder unit is located at a central position of the hydraulic cylinder units of the inner annular row.

3. The hydraulic cylinder units in the outer annular row are referred to in order along the circumferential direction as the No. 1 hydraulic cylinder unit, the No. 2 hydraulic cylinder unit, the No. 3 hydraulic cylinder unit, the No. 4 hydraulic cylinder unit, the No. 5 hydraulic cylinder unit, the No. 6 hydraulic cylinder unit, the No. 7 hydraulic cylinder unit, the No. 8 hydraulic cylinder unit, the No. 9 hydraulic cylinder unit, the No. 10 hydraulic cylinder unit, the No. 11 hydraulic cylinder unit, and the No. 12 hydraulic cylinder unit, the hydraulic cylinder units in the inner annular row are referred to in order along the circumferential direction as the No. 13 hydraulic cylinder unit, the No. 14 hydraulic cylinder unit, the No. 15 hydraulic cylinder unit, the No. 16 hydraulic cylinder unit, the No. 17 hydraulic cylinder unit, and the No. 18 hydraulic cylinder unit, and the hydraulic cylinder unit at the center position is referred to as the No. 19 hydraulic cylinder unit, 3. The power plant governor execution unit according to claim 2, wherein the control valve unit includes five valve unit modules, one of which controls the first, third, fifth, seventh, nineth, and eleventh hydraulic cylinder units to supply oil simultaneously, one of which controls the second, fourth, sixth, eighth, tenth, and twelfth hydraulic cylinder units to supply oil simultaneously, one of which controls the thirteenth, fifteenth, and seventeenth hydraulic cylinder units to supply oil simultaneously, one of which controls the fourteenth, sixteenth, and eighteenth hydraulic cylinder units to supply oil simultaneously, and one of which controls the nineteenth hydraulic cylinder unit to supply oil.

4. The execution unit for a governor of a power plant according to any one of claims 1 to 3, characterized in that the hydraulic cylinder further includes an outer cylinder block, and both ends of the outer cylinder block are provided with a front cylinder block end plate and a rear cylinder block end plate, the rear end of the unit cylinder block of each hydraulic cylinder unit is fixed to the rear cylinder block end plate, and the power output rod has a small diameter segment that is fitted into the front cylinder block end plate so as to be guided and movable, and a large diameter segment that is fitted into the inner cavity of the outer cylinder block so as to be guided and movable.

5. The execution unit for a governor of a power plant according to claim 4, characterized in that the large diameter segment has a communication hole that communicates with the internal cavities of the outer cylinder blocks on both the front and rear sides of the large diameter segment, the front end of the unit cylinder block of each hydraulic cylinder unit has a front end oil port connected to the second piston chamber, the rear end of the unit cylinder block of each hydraulic cylinder unit has a rear end oil port connected to the first piston chamber, and each unit cylinder block has a cylinder block oil path whose front end is connected to the front end oil port.

6. The execution unit for a governor of a power plant described in claim 4, characterized in that the rear cylinder block end plate is provided with an end plate first oil port that connects a corresponding rear end oil port with the control valve unit, and an end plate second oil port that connects the rear end of the cylinder block oil path with the control valve unit.

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