An execution unit for a power plant speed regulator

Abstract

The present invention relates to an actuator unit for a power plant speed governor, comprising a hydraulic cylinder and an oil pressure system, the oil pressure system comprising an oil tank and an oil pump. The hydraulic cylinder comprises a plurality of hydraulic cylinder units arranged in parallel, each hydraulic cylinder unit comprising a unit cylinder body and a unit piston rod guided and movable and assembled on the corresponding unit cylinder body. The hydraulic cylinder further comprises a power output rod connected to the power output end of each unit piston rod, the piston of the unit piston rod dividing the unit cylinder body 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 circuit. The hydraulic oil circuit is provided with a control valve group, the control valve group having multiple control modes. In each control mode, the hydraulic oil circuit supplies oil to a different number of hydraulic cylinder units. The present invention provides an actuator unit for a power plant speed governor that can adjust the output force value by changing the pressure area of the piston.

Description

Technical Field

[0001] The invention relates to a supporting execution component of a power plant speed regulating device, in particular to an execution unit for a power plant speed regulator. Background Art

[0002] In a hydroelectric power plant, the amount of water entering is changed by opening and closing the guide vanes, thereby controlling the power generation of the generator. The opening and closing of the guide vanes is controlled by an actuator unit. The actuator unit mainly includes a hydraulic cylinder and an oil pressure device. The oil pressure device includes an oil tank, an oil pump, and a hydraulic oil circuit connected between the oil pump and the hydraulic cylinder. A flow regulating valve is provided on the hydraulic oil circuit.

[0003] During operation, the output force and speed of the hydraulic cylinder are regulated by adjusting the flow control valve or pump station power. This control method has the following problems: Since the hydraulic cylinder thrust F = P * S, where S represents the cross-sectional area of the hydraulic cylinder piston, which is a fixed quantity, and P represents the oil pressure within the hydraulic cylinder, which is a variable, this control method can be achieved by changing the pump station power and the flow control valve. However, this traditional oil pressure adjustment method is dependent on sudden starts, stops, speed changes, or reversals in the hydraulic system, as well as sudden closing or cessation of the flow control valve orifice. Due to the inertia of the flowing fluid and moving parts, high peak pressures can be generated within the system. This phenomenon is called hydraulic shock, which can cause significant damage to the hydraulic system and introduce errors in hydraulic adjustment. Especially during the guide vane adjustment process in hydroelectric power plants, the guide vanes are constantly subjected to load, but this force is not stable. This creates an elastic reaction force on the corresponding hydraulic equipment. This reaction force acts on the driving hydraulics, affecting the thrust and speed adjustment of the hydraulic cylinder. Summary of the Invention

[0004] The object of the present invention is to provide an actuator for a power plant speed governor, which can adjust the output force value by changing the pressure area of a piston.

[0005] To solve the above technical problems, the technical solution of an execution unit for a power plant speed governor in the present invention is as follows:

[0006] An actuator unit for a power plant speed governor includes a hydraulic cylinder and an oil pressure system. The oil pressure system includes an oil tank and an oil pump. The hydraulic cylinder includes a plurality of hydraulic cylinder units arranged in parallel. Each hydraulic cylinder unit includes a unit cylinder body and a unit piston rod guided and movable and assembled on the corresponding unit cylinder body. The hydraulic cylinder also 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 body 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 through a hydraulic oil circuit. A control valve group is provided on the hydraulic oil circuit. The control valve group has multiple control modes. Under each control mode, the hydraulic oil circuit supplies oil to a different number of hydraulic cylinder units.

[0007] Furthermore, there are a total of 19 hydraulic cylinder units, of which 18 hydraulic cylinder units are arranged in two concentric circles. The inner circle includes 6 hydraulic cylinder units evenly spaced along the circumference, and the outer circle includes 12 hydraulic cylinder units evenly spaced along the circumference. The last hydraulic cylinder unit is located at the center of the inner circle of hydraulic cylinder units.

[0008] Furthermore, the outer circle of hydraulic cylinder units are respectively referred to as No. 1 hydraulic cylinder unit, No. 2 hydraulic cylinder unit, No. 3 hydraulic cylinder unit, No. 4 hydraulic cylinder unit, No. 5 hydraulic cylinder unit, No. 6 hydraulic cylinder unit, No. 7 hydraulic cylinder unit, No. 8 hydraulic cylinder unit, No. 9 hydraulic cylinder unit, No. 10 hydraulic cylinder unit, No. 11 hydraulic cylinder unit and No. 12 hydraulic cylinder unit in the circumferential order, and the inner circle of hydraulic cylinder units are respectively referred to as No. 13 hydraulic cylinder unit, No. 14 hydraulic cylinder unit, No. 15 hydraulic cylinder unit, No. 16 hydraulic cylinder unit, No. 17 hydraulic cylinder unit in the circumferential order. Yuanhe No. 18 hydraulic cylinder unit, the hydraulic cylinder unit in the center position is called hydraulic cylinder unit No. 19, the control valve group includes five valve group modules, one of which controls the oil supply of hydraulic cylinder units No. 1, 3, 5, 7, 9, and 11 at the same time, one of which controls the oil supply of hydraulic cylinder units No. 2, 4, 6, 8, 10, and 12 at the same time, one of which controls the oil supply of hydraulic cylinder units No. 13, 15, and 17 at the same time, one of which controls the oil supply of hydraulic cylinder units No. 14, 16, and 18 at the same time, and one of which controls the oil supply of hydraulic cylinder unit No. 19.

[0009] Furthermore, the hydraulic cylinder also includes an outer cylinder body, and a front cylinder end plate and a rear cylinder end plate are provided at both ends of the outer cylinder body. The rear end of the unit cylinder of each hydraulic cylinder unit is fixed on the said rear cylinder end plate, and the power output rod includes a small diameter section that cooperates with the guiding movement of the front cylinder end plate and a large diameter section that cooperates with the guiding movement of the inner cavity of the outer cylinder body.

[0010] Furthermore, a connecting hole is provided on the large diameter section to connect the inner cavity of the outer cylinder body on the front and rear sides of the large diameter section. The front end of the unit cylinder body of each hydraulic cylinder unit is provided with a front oil port connected to the second piston chamber, and the rear end of the unit cylinder body of each hydraulic cylinder unit is provided with a rear end oil port connected to the first piston chamber. Each unit cylinder body is provided with a cylinder oil channel whose front end is connected to the front oil port.

[0011] Furthermore, the rear cylinder end plate is provided with a first end plate oil port connecting the corresponding rear end oil port with the control valve group and a second end plate oil port connecting the rear end of the cylinder oil channel with the control valve group.

[0012] The beneficial effects of the present invention are as follows: the multiple hydraulic cylinder units in the present invention output power outward through the same power output rod. According to the demand for output force, the control valve group can choose to supply oil to the corresponding number of hydraulic cylinder units, thereby changing the overall piston force area of the hydraulic cylinder, and ultimately changing the output force value of the hydraulic cylinder. There is no need to frequently change the oil pump speed or the opening of the corresponding valve. The oil pressure in the hydraulic oil circuit can be stable, reducing the generation of hydraulic shock. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an illustrative and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0014] Figure 1 This is a structural diagram of an embodiment of an execution unit for a power plant speed governor in the present invention;

[0015] Figure 2 yes Figure 1 Schematic diagram of the structure of the hydraulic cylinder;

[0016] Figure 3 yes Figure 1 Schematic diagram of the distribution of each hydraulic cylinder unit;

[0017] Figure 4 This is a control diagram of the control valve group and each hydraulic unit in the present invention;

[0018] Figure 5 yes Figure 1 Schematic diagram of the hydraulic cylinder unit with the piston rod extended;

[0019] Explanation of the accompanying drawings: 1. Oil tank; 2. Oil pump; 3. Control valve group; 4. Hydraulic oil circuit; 5. Hydraulic cylinder; 6. Hydraulic cylinder unit; 7. Unit piston rod; 8. First piston chamber; 9. Rear cylinder end plate; 10. Power output rod; 11. Rear end oil port; 12. Unit cylinder; 13. End plate first oil port; 14. Front end oil port; 15. Front cylinder end plate; 16. Small diameter section; 17. Large diameter section; 18. Connecting hole; 19. Outer cylinder; 20. Pump station; 21. Controller; 22. Cylinder oil channel; 23. End plate second oil port; 24. Cylinder protrusion. DETAILED DESCRIPTION

[0020] To facilitate understanding of the present invention, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0021] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0022] An example of an implementation of an execution unit for a power plant speed regulator in the present invention is as follows: Figures 1 to 5 As shown: it includes a pump station and a hydraulic cylinder. The pump station includes an oil pressure system. The oil pressure system includes an oil tank 1 and an oil pump 2. The oil pump 2 is arranged on the oil tank.

[0023] The hydraulic cylinder includes an outer cylinder body 19 and a plurality of hydraulic cylinder units 6 arranged in parallel. In the present invention, the number of hydraulic cylinder units 6 is 19, and the axis of each hydraulic cylinder unit 6 is extended along the front and rear directions. The front and rear ends of the outer cylinder body 19 are respectively fixed with a front cylinder end plate 15 and a rear cylinder end plate 9. The outer cylinder body, the front cylinder end plate and the rear cylinder end plate form a cavity. Each hydraulic cylinder unit 6 includes a unit cylinder body 12 and a unit piston rod 7 guided and moved on the unit cylinder body along the front and rear directions. Each hydraulic cylinder unit 6 is arranged in the cavity.

[0024] In this embodiment, the rear end of the unit cylinder body 12 of each hydraulic cylinder unit is fixed on the rear cylinder end plate 9. The unit cylinder body of each hydraulic cylinder unit is an integrally formed structure. The piston of the unit piston rod divides the unit cylinder body into a first piston chamber 8 and a second piston chamber. The second piston chamber is located on the front side of the first piston chamber 8. The hydraulic cylinder also includes a power output rod 10 connected to the power output end of each unit piston rod. The power output rod 10 includes a small diameter section 16 that cooperates with the guiding movement of the front cylinder end plate and a large diameter section 17 that cooperates with the guiding movement of the outer cylinder body inner cavity. The large diameter section and small diameter section in this embodiment are relative. The outer diameter of the large diameter section is larger than the outer diameter of the small diameter section, so it is called a large diameter section.

[0025] The large diameter section 17 is fixed to the front end of the unit piston rod 7 of each hydraulic cylinder unit. A connecting hole 18 is opened on the large diameter section to connect the inner cavity of the outer cylinder body on the front and rear sides of the large diameter section. In this embodiment, there are multiple connecting holes, and the multiple connecting holes are distributed circumferentially at intervals on the outer periphery of the large diameter section.

[0026] The oil pump is connected to the first and second piston chambers of each hydraulic cylinder unit via a hydraulic oil circuit 4. A control valve assembly 3 is provided on the hydraulic oil circuit. This control valve assembly 3 has multiple control modes. In each control mode, the hydraulic oil circuit supplies oil to a different number of hydraulic cylinder units. Specifically, each hydraulic cylinder unit has a front oil port 14 connected to the second piston chamber at the front end of the unit cylinder body. A cylinder protrusion 24 is provided on the outer periphery of the unit cylinder body. A cylinder oil passage 22 extending in the front-to-back direction is provided within the cylinder protrusion. The front end of the cylinder oil passage 22 is connected to the front oil port 14.

[0027] Each hydraulic cylinder unit has a rear end oil port 11 connected to the corresponding first piston chamber at the rear end of the cylinder body. A first end plate oil port 13 is provided on the rear end plate, connecting the corresponding rear end oil port with the control valve group. A second end plate oil port 23 is also provided on the rear end plate, connecting the rear end of the corresponding cylinder oil passage 22 with the control valve group 3. Item 21 in the figure represents a controller that controls the operation of the control valve group 3.

[0028] In this embodiment, 18 of the 19 hydraulic cylinder units are arranged in two concentric circles. The inner circle includes six hydraulic cylinder units evenly spaced circumferentially, while the outer circle includes 12 hydraulic cylinder units evenly spaced circumferentially. The last hydraulic cylinder unit is located at the center of the inner circle. Within a circle of hydraulic cylinder units, the axes of all hydraulic cylinder units lie on a circle, with the cylinder body protrusion located outside of this circle. This arrangement helps reduce the circumferential space occupied by the hydraulic cylinder units in that circle, while also reducing the radial space occupied by all hydraulic cylinder units.

[0029] The outer circle of hydraulic cylinder units are called No. 1 hydraulic cylinder unit, No. 2 hydraulic cylinder unit, No. 3 hydraulic cylinder unit, No. 4 hydraulic cylinder unit, No. 5 hydraulic cylinder unit, No. 6 hydraulic cylinder unit, No. 7 hydraulic cylinder unit, No. 8 hydraulic cylinder unit, No. 9 hydraulic cylinder unit, No. 10 hydraulic cylinder unit, No. 11 hydraulic cylinder unit and No. 12 hydraulic cylinder unit in order along the circumferential direction, and the inner circle of hydraulic cylinder units are called No. 13 hydraulic cylinder unit, No. 14 hydraulic cylinder unit, No. 15 hydraulic cylinder unit, No. 16 hydraulic cylinder unit, No. 17 hydraulic cylinder unit and No. 18 hydraulic cylinder unit in order along the circumferential direction. Hydraulic cylinder unit No. 18, the hydraulic cylinder unit in the center position is called hydraulic cylinder unit No. 19, the control valve group includes five valve group modules, one of which controls the oil supply to hydraulic cylinder units No. 1, 3, 5, 7, 9, and 11 at the same time, one of which controls the oil supply to hydraulic cylinder units No. 2, 4, 6, 8, 10, and 12 at the same time, one of which controls the oil supply to hydraulic cylinder units No. 13, 15, and 17 at the same time, one of which controls the oil supply to hydraulic cylinder units No. 14, 16, and 18 at the same time, and one of which controls the oil supply to hydraulic cylinder unit No. 19.

[0030] During use, the number of working hydraulic cylinder units can be selected according to the output force requirement of the hydraulic cylinder. For example, when one hydraulic cylinder unit can meet the overall output force requirement of the hydraulic cylinder, the corresponding valve group module of the control valve group controls the pump station to supply oil to the first piston chamber of hydraulic cylinder unit No. 19, and the oil in the second piston chamber of hydraulic cylinder unit No. 19 flows back to the oil tank through the cylinder body oil channel and the control valve group. The first piston chambers of other hydraulic cylinder units are connected to the bottom of the oil tank through the control valve group. That is to say, when the power output rod is driven by one of the hydraulic cylinder units and moves forward, the first piston chambers of other hydraulic cylinder units are in the oil pumping state, and the pressure-free oil in the oil tank is pumped into the corresponding first piston chamber.

[0031] That is to say, a hydraulic cylinder unit has a working state and an idle state. In the working state, when the unit piston rod needs to be extended, oil is pumped to the first piston chamber through the control valve group, and the hydraulic oil in the second piston chamber flows back to the oil tank through the cylinder oil passage and the control valve group; when the unit piston rod needs to be extended, oil is pumped to the second piston chamber through the control valve group and the cylinder oil passage, and the hydraulic oil in the first piston chamber flows back to the oil tank through the control valve group. In the idle state, when the unit piston rod is extended along with the power output rod, the first piston chamber is connected to the oil tank through the control valve group, and the second piston chamber is connected to the oil tank through the cylinder oil passage and the control valve group, and the hydraulic oil in the second piston chamber flows back to the oil tank, while hydraulic oil is pumped into the first piston chamber; when the unit piston rod is retracted along with the power output rod, the hydraulic oil in the first piston chamber flows back to the oil tank, and the second piston chamber is pumped into the oil tank through the cylinder oil passage and the control valve group.

[0032] By the same token, you can also choose to have three hydraulic cylinder units output power simultaneously, four hydraulic cylinder units output power simultaneously, six hydraulic cylinder units output power simultaneously, seven hydraulic cylinder units output power simultaneously, nine hydraulic cylinder units output power simultaneously, eighteen hydraulic cylinder units output power simultaneously, and nineteen hydraulic cylinder units output power simultaneously. When different numbers of hydraulic cylinder units output power, the pressure cross-sectional area of the unit piston rod that bears the hydraulic pressure is different. Therefore, even if the oil pressure remains consistent, the overall outward output force of the hydraulic cylinder can be changed by changing the number of working hydraulic cylinder units. In this embodiment, the hydraulic cross-sectional area borne by the piston rods of each unit is the same. In other embodiments of the present invention, the hydraulic cross-sectional area borne by the piston rods of each unit may also be different. Through the special layout of the hydraulic cylinder units, regardless of the working mode, it can be ensured that the force direction of the power output rod is always consistent with the axis of the power output rod.

[0033] In the foregoing description of this specification, unless otherwise expressly specified or limited, terms such as "fixed," "mounted," "connected," or "connected" should be understood broadly. For example, the term "connected" can refer to a fixed connection, a removable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediary; or the internal connection between two components or the interaction between two components. Therefore, unless otherwise expressly defined in this specification, those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0034] According to the above description of this specification, those skilled in the art may also understand that the terms used below, such as "up", "down", "front", "back", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", "center", "longitudinal", "transverse", "clockwise" or "counterclockwise", etc., which indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the drawings of this specification, and are only for the purpose of facilitating the explanation of the scheme of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the device or element involved must have the specific orientation, be constructed and operate in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms cannot be understood or interpreted as limitations on the scheme of the present invention.

[0035] In addition, the terms "first" or "second" used in this specification to refer to numbers or ordinal numbers are used for descriptive purposes only and should not be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this specification, "plurality" means at least two, such as two, three or more, etc., unless otherwise clearly specified.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An actuator unit for a power plant speed governor, comprising a hydraulic cylinder and an oil pressure system, wherein the oil pressure system comprises an oil tank and an oil pump, and is characterized in that: The hydraulic cylinder includes a plurality of hydraulic cylinder units arranged in parallel, each hydraulic cylinder unit includes a unit cylinder body and a unit piston rod guided and movable on the corresponding unit cylinder body, the hydraulic cylinder also 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 body 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 through a hydraulic oil circuit, a control valve group is provided on the hydraulic oil circuit, the control valve group has a plurality of control modes, under each control mode, the hydraulic oil circuit supplies oil to a different number of hydraulic cylinder units, There are 19 hydraulic cylinder units in total, of which 18 hydraulic cylinder units are arranged in two concentric circles. The inner circle includes 6 hydraulic cylinder units evenly spaced along the circumference, and the outer circle includes 12 hydraulic cylinder units evenly spaced along the circumference. The last hydraulic cylinder unit is located at the center of the inner circle of hydraulic cylinder units. The outer circle of hydraulic cylinder units are called No. 1 hydraulic cylinder unit, No. 2 hydraulic cylinder unit, No. 3 hydraulic cylinder unit, No. 4 hydraulic cylinder unit, No. 5 hydraulic cylinder unit, No. 6 hydraulic cylinder unit, No. 7 hydraulic cylinder unit, No. 8 hydraulic cylinder unit, No. 9 hydraulic cylinder unit, No. 10 hydraulic cylinder unit, No. 11 hydraulic cylinder unit and No. 12 hydraulic cylinder unit in order along the circumferential direction, and the inner circle of hydraulic cylinder units are called No. 13 hydraulic cylinder unit, No. 14 hydraulic cylinder unit, No. 15 hydraulic cylinder unit, No. 16 hydraulic cylinder unit, No. 17 hydraulic cylinder unit and No. 18 hydraulic cylinder unit in order along the circumferential direction. Hydraulic cylinder unit No. 18, the hydraulic cylinder unit in the center position is called hydraulic cylinder unit No. 19, the control valve group includes five valve group modules, one of which controls the oil supply to hydraulic cylinder units No. 1, 3, 5, 7, 9, and 11 at the same time, one of which controls the oil supply to hydraulic cylinder units No. 2, 4, 6, 8, 10, and 12 at the same time, one of which controls the oil supply to hydraulic cylinder units No. 13, 15, and 17 at the same time, one of which controls the oil supply to hydraulic cylinder units No. 14, 16, and 18 at the same time, and one of which controls the oil supply to hydraulic cylinder unit No.

19.

2. The execution unit for a power plant speed governor according to claim 1, characterized in that: The hydraulic cylinder also includes an outer cylinder body, and a front cylinder end plate and a rear cylinder end plate are provided at both ends of the outer cylinder body. The rear end of the unit cylinder of each hydraulic cylinder unit is fixed to the said rear cylinder end plate, and the power output rod includes a small diameter section that cooperates with the guiding movement of the front cylinder end plate and a large diameter section that cooperates with the guiding movement of the inner cavity of the outer cylinder body.

3. The execution unit for a power plant speed governor according to claim 2, characterized in that: A connecting hole is provided on the large diameter section to connect the inner cavity of the outer cylinder body on the front and rear sides of the large diameter section. The front end of the unit cylinder body of each hydraulic cylinder unit is provided with a front oil port connected to the second piston chamber, and the rear end of the unit cylinder body of each hydraulic cylinder unit is provided with a rear end oil port connected to the first piston chamber. Each unit cylinder body is provided with a cylinder oil channel whose front end is connected to the front oil port.

4. The execution unit for a power plant speed governor according to claim 2, characterized in that: The rear cylinder end plate is provided with a first end plate oil port communicating with the corresponding rear end oil port and the control valve group, and a second end plate oil port communicating with the rear end of the cylinder oil passage and the control valve group.

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