An optimized control device for guide vane of axial flow variable pitch water turbine

Abstract

The utility model relates to the field of hydraulic turbine, concretely relates to a kind of axial flow variable pitch water turbine guide vane optimization control device, the utility model includes ring body and two thrust cylinders, two thrust cylinders are located ring body both sides respectively, the output shaft of thrust cylinder is all hinged with tension rod, and the end of tension rod away from thrust cylinder is all connected with ring body top rotation;Ring body bottom is rotationally connected with several connecting rods in uniform circumferentially, and the end of connecting rod away from ring body is rotationally connected with control arm, and the end of control arm away from connecting rod is provided with coordination hole, and coordination hole top is rotationally connected with guide vane end cover, and coordination hole bottom is equipped with guide vane plate.The technical scheme of the utility model is used to control the opening of axial flow variable pitch water turbine, so that the opening can adapt to the working condition and bring higher energy efficiency.

Description

Technical Field

[0001] This utility model relates to the field of water turbine technology, and more specifically, to an optimized control device for guide vanes of an axial-flow propeller-type water turbine. Background Technology

[0002] As the core power equipment of low-head, high-flow hydropower stations, the axial-flow propeller turbine's key advantage lies in the dynamic adjustment of the runner blade angle according to changes in head and load, forming a specific matching relationship with the opening of the movable guide vanes—this is known as "coordination." Precise coordination control allows the turbine to maintain high energy conversion efficiency over a wide operating range, significantly improving the power station's economic benefits and energy utilization. However, current coordination control methods have significant drawbacks. First, current coordination control relies on model tests and limited field efficiency test data to pre-set fixed coordination curves. This static control strategy cannot adapt to the changing operating conditions encountered after the unit begins operation. For example, increased surface roughness and flow channel deformation due to silt abrasion, cavitation, and biofouling of flow passage components, as well as increased mechanical transmission clearances, all cause the turbine's actual output characteristics to "drift" away from the preset operating conditions, leading to a gradual deviation of the preset coordination relationship from its optimal state and resulting in energy loss. Second, obtaining precise coordination relationships is costly. Relying on equipment such as ultrasonic flow meters for prototype efficiency testing consumes a significant amount of manpower and resources, which is detrimental to the economic benefits of generator sets. This makes it difficult for many power plants to fully verify and optimize the coordination curves in the field. At the same time, since manufacturing and installation errors cannot be completely avoided, the optimal coordination relationship of the same model of generator set may differ. A fixed curve is difficult to apply universally and cannot meet the individual operating requirements of the generator set. Utility Model Content

[0003] To address the aforementioned problems, this invention provides an optimized control device for the guide vanes of an axial-flow propeller turbine, used to regulate the opening degree of the axial-flow propeller turbine so that the opening degree can adapt to the operating conditions and bring about higher energy efficiency.

[0004] This utility model is achieved through the following technical solution: an optimized control device for guide vanes of an axial-flow propeller turbine, comprising a ring body and two thrust cylinders, the two thrust cylinders being located on both sides of the ring body respectively, and the output shaft of each thrust cylinder being hinged with a tension rod, the end of the tension rod away from the thrust cylinder being rotatably connected to the top of the ring body; Several connecting rods are rotatably connected to the bottom of the ring body. A control arm is rotatably connected to the end of the connecting rod away from the ring body. A matching hole is opened at the end of the control arm away from the connecting rod. A guide vane end cap is rotatably connected to the top of the matching hole. A guide vane plate is fitted at the bottom of the matching hole.

[0005] Furthermore, the thruster includes a cylinder block, a cylinder head fixedly connected to the top of the cylinder block, the cylinder block and the cylinder head forming a closed oil chamber, a cylinder liner slidably connected inside the oil chamber, and a piston rod fixedly connected to the bottom of the cylinder liner.

[0006] Furthermore, the piston rod surface is provided with a ground chrome plating layer.

[0007] Furthermore, it also includes a controller, and a displacement sensor is installed inside the cylinder. Both the displacement sensor and the thruster are connected to the controller via signals.

[0008] Furthermore, the connecting rods are all hinged to the ring body via rod pins, and several threaded sleeves are threaded onto the connecting rods.

[0009] Furthermore, a guide rail is fixedly connected to the middle section of the ring in the height direction, and a detection block is slidably connected to the guide rail. The detection block is equipped with a driving component that drives the detection block to slide on the guide rail. Two laser rangefinders are provided at the bottom of the detection block, and the laser rangefinders are located on both sides of the detection block.

[0010] Furthermore, a groove is provided on the connecting rod along the length of the connecting rod.

[0011] Furthermore, the width of the groove is less than 1 / 2 of the width of the connecting rod.

[0012] Furthermore, the driving component is a roller driven by a motor.

[0013] Furthermore, the end of the tension rod near the thrust cylinder is hinged to the piston rod via a heavy-duty joint.

[0014] The technical solution of this utility model has at least the following beneficial effects: The ring body in this scheme is integrated into the axial-flow propeller turbine. Its function is to adjust the blade opening of the axial-flow propeller turbine, thereby ensuring that more water kinetic energy can be converted into electrical energy.

[0015] The thrust cylinder is used to provide driving force, and the matching hole of the control arm is used to install the blade pivot of the axial-flow propeller turbine. It is fixedly connected to the blade pivot of the axial-flow propeller turbine through the guide vane end cover, so that the guide vane plate can effectively move the blade pivot in the matching hole.

[0016] When this scheme implements blade control, the thrust cylinder on one side of the ring retracts while the thrust cylinder on the other side extends, causing the ring to rotate. Both ends of the tension rod are hinged to accommodate changes in the connection point after the ring rotates. The thrust cylinder provides a large driving force to overcome the work done by the water flow, thus effectively driving the blades to adjust their opening. The connecting rod hinged at the bottom of the ring is driven by the ring's rotation, pulling the control arm. Because the control arm is constrained by the matching hole and the blade pivot of the axial-flow propeller turbine, it rotates around the blade pivot, causing the guide vane to drive the blade pivot to rotate and adjust the blade opening of the axial-flow propeller turbine. By adjusting the blade opening, the blade opening can adapt to the water flow conditions under various influences, thereby achieving higher energy conversion efficiency. Attached Figure Description Figure 1 This is an isometric schematic diagram of an embodiment of the axial-flow propeller turbine guide vane optimization control device of this utility model; Figure 2 This is a top view schematic diagram of an embodiment of the axial flow propeller turbine guide vane optimization control device of this utility model; Figure 3 This is a schematic diagram of the detection block in an embodiment of the axial-flow propeller turbine guide vane optimization control device of this utility model; Figure 4 This is a schematic diagram of the connecting rod in an embodiment of the axial-flow propeller turbine guide vane optimization control device of this utility model; Figure 5 This is a schematic diagram of the matching hole in an embodiment of the axial-flow propeller turbine guide vane optimization control device of this utility model.

[0017] Reference numerals: 1. Ring body; 2. Thrust cylinder; 3. Pull rod; 4. Connecting rod; 5. Control arm; 6. Matching hole; 7. Guide vane end cap; 8. Guide vane plate; 9. Rod pin; 10. Guide rail; 11. Detection block; 12. Drive component; 13. Laser rangefinder; 14. Groove; 15. Screw sleeve; 201. Cylinder body; 202. Cylinder head; 203. Cylinder liner; 204. Piston rod. Detailed Implementation

[0018] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0019] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0021] The following detailed description illustrates the specific implementation method: Example 1 As attached Figures 1-5 As shown, an optimized control device for guide vanes of an axial-flow propeller turbine includes an annular body 1 and two thrust cylinders 2, located on opposite sides of the annular body 1. Each thruster includes a cylinder body 201, with a cylinder head 202 bolted to the top. The cylinder body 201 and cylinder head 202 form a closed oil chamber. A cylinder liner 203 is slidably connected within the oil chamber, and a piston rod 204 is bolted to the bottom of the cylinder liner 203. The surface of the piston rod 204 is coated with a ground chrome plating layer. Each piston rod 204 of the thrust cylinder 2 is hinged to a tension rod 3. The end of the tension rod 3 closest to the thrust cylinder 2 is hinged to the piston rod 204 via a heavy-duty joint, while the end of the tension rod 3 furthest from the thrust cylinder 2 is rotatably connected to the top of the annular body 1.

[0022] The bottom of the ring body 1 is circumferentially connected to several connecting rods 4. The end of the connecting rod 4 away from the ring body 1 is rotatably connected to a control arm 5. The end of the control arm 5 away from the connecting rod 4 is provided with a matching hole 6. The top of the matching hole 6 is rotatably connected to a guide vane end cap 7. The bottom of the matching hole 6 is fitted with a guide vane plate 8.

[0023] It also includes a controller, and a displacement sensor (not shown in the figure) is installed in the cylinder 201. The displacement sensor is used to detect the displacement distance of the piston rod 204. Both the displacement sensor and the thruster are connected to the controller signal.

[0024] Propeller turbines generate electricity by rotating blades driven by water flow. Typically, water enters a spiral pipe with several outlets. The water flowing out of these outlets impacts the blades in a circumferential motion, causing them to rotate. The pipe diameter decreases towards the end to balance the pressure at each outlet. However, increased surface roughness due to silt abrasion, cavitation, and biological adhesion, along with channel deformation, alters the impact point of the water flow, reducing the impact on the blades and lowering power generation efficiency. Therefore, active blade adjustment is necessary to change the blade opening according to variations in water flow.

[0025] In this embodiment, the ring 1 is integrated into the axial-flow propeller turbine. Its function is to adjust the blade opening of the axial-flow propeller turbine, thereby ensuring that more water kinetic energy can be converted into electrical energy.

[0026] The thrust cylinder 2 provides driving force. The matching hole 6 of the control arm 5 is used to install the blade pivot of the axial-flow propeller turbine. It is fixedly connected to the blade pivot of the axial-flow propeller turbine through the guide vane end cover 7, thereby enabling the guide vane plate 8 to effectively move the blade pivot within the matching hole 6. The thruster adopts a hydraulic cylinder structure to provide a large driving force, enabling the blade to twist against the water flow. The piston rod 204 needs to have high strength and good wear resistance. Therefore, high-strength alloy steel is used as the material, and its surface is precision ground and chrome-plated, resulting in extremely high smoothness, hardness, and corrosion resistance, ensuring long-term stable operation when paired with the cylinder liner 203. One end of the piston rod 204 is connected to the tension rod 3 through a heavy-duty spherical bearing. This connection method allows for the transmission of huge thrust / pull forces while compensating for minor misalignment that may occur during installation and operation, preventing jamming.

[0027] The thruster integrates a displacement sensor to detect the absolute position of the piston rod 204 in real time and feeds this position signal back to the controller, forming the basis of position closed-loop control. Then, the thruster's extension and retraction are precisely adjusted through negative feedback control.

[0028] In this embodiment, when the blade control is executed, the thrust cylinder 2 on one side of the ring body 1 contracts while the thrust cylinder 2 on the other side extends, causing the ring body 1 to rotate. Depending on which thrust cylinder 2 is extended or retracted, the ring body 1 is driven to rotate clockwise or counterclockwise. Both ends of the tension rod 3 are hinged to adapt to the change in the arc trajectory of the connection point after the ring body 1 rotates. The thrust cylinder 2 provides a large driving force to overcome the work done by the water flow, thereby effectively driving the blade to rotate. The connecting rod 4 hinged at the bottom of the ring body 1 is driven by the rotation of the ring body 1, thereby pulling the control arm 5. The control arm 5 is constrained by the matching hole 6 and the blade pivot of the axial flow propeller turbine, so the control arm 5 will rotate around the blade pivot, thereby causing the guide vane plate 8 to drive the blade pivot to rotate and adjust the blade opening of the axial flow propeller turbine. By adjusting the blade opening, the blade opening can be adapted to the water flow after being affected by various factors, thereby obtaining higher energy conversion efficiency.

[0029] Example 2 The difference from the above embodiment is that the connecting rod 4 is hinged to the ring body 1 through the rod pin 9, and the connecting rod 4 is threaded with a number of threaded sleeves 15.

[0030] The pin 9 ensures a stable connection between the connecting rod 4 and the ring 1. After the connecting rod 4 is installed, due to installation or manufacturing errors, the rotation of each connecting rod 4 under the action of the ring 1 may be different. The threaded sleeve 15 can precisely adjust the center of gravity distribution of the connecting rod 4, thereby adjusting the attitude of the connecting rod 4 after the ring 1 rotates. This design is used to ensure that all blades move synchronously after the device is installed or overhauled, eliminating manufacturing and installation errors.

[0031] Example 3 The difference from the above embodiment is that a guide rail 10 is bolted to the middle section of the ring 1 in the height direction, and a detection block 11 is slidably connected to the guide rail 10. The detection block 11 is provided with a driving component 12 that drives the detection block 11 to slide on the guide rail 10. The driving component 12 is a roller driven by a motor. Two small laser rangefinders 13 are bolted to the bottom of the detection block 11, and the laser rangefinders 13 are located on both sides of the detection block 11. A groove 14 is opened on the connecting rod 4 along the length direction of the connecting rod 4, and the width of the groove 14 is less than 1 / 2 of the width of the connecting rod 4.

[0032] During deployment, it is necessary to check whether each link 4 is synchronized. During operation, the propellers also transmit power to the control arm 5, interfering with the attitude of the links 4 and causing them to become out of sync. Therefore, a guide rail 10 is installed in the middle section of the ring body 1 in the height direction. Two laser rangefinders 13 are installed on the detection block 11 at the bottom of the guide rail 10. These rangefinders can determine the positions of two points on the links 4 based on changes in the detection data during inspection, thereby determining the attitude of the links 4. Specifically, the links 4 block the laser beam path of the laser rangefinders 13. When the laser rangefinders 13 move above the links 4, the distance detection value of the laser rangefinders 13 decreases, thus determining the intersection point of the laser beams from the links 4 and 13. The detection block 11 can rotate along the ring body 1 to detect each link 4 and verify whether the attitude of the links 4 is uniform. The groove 14, through the resulting changes in the distance detection value, narrows the detection range to a smaller area, improving the positioning accuracy of the points.

[0033] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A guide vane optimization control device for an axial-flow propeller turbine, characterized in that, It includes a ring body (1) and two thrust cylinders (2). The two thrust cylinders (2) are located on both sides of the ring body (1). The output shaft of each thrust cylinder (2) is hinged with a tension rod (3). The end of the tension rod (3) away from the thrust cylinder (2) is rotatably connected to the top of the ring body (1). The bottom of the ring body (1) is circumferentially connected to several connecting rods (4). The end of the connecting rod (4) away from the ring body (1) is rotatably connected to a control arm (5). The end of the control arm (5) away from the connecting rod (4) is provided with a matching hole (6). The top of the matching hole (6) is rotatably connected to a guide vane end cap (7). The bottom of the matching hole (6) is fitted with a guide vane plate (8).

2. The axial-flow propeller turbine guide vane optimization control device according to claim 1, characterized in that, The thruster includes a cylinder body (201), a cylinder head (202) is fixedly connected to the top of the cylinder body (201), the cylinder body (201) and the cylinder head (202) form a closed oil chamber, a cylinder liner (203) is slidably connected in the oil chamber, and a piston rod (204) is fixedly connected to the bottom of the cylinder liner (203).

3. The axial-flow propeller turbine guide vane optimization control device according to claim 2, characterized in that, The piston rod (204) has a ground chrome plating layer on its surface.

4. The axial-flow propeller turbine guide vane optimization control device according to claim 3, characterized in that, It also includes a controller, and a displacement sensor is provided inside the cylinder (201). The displacement sensor and the thruster are both connected to the controller signal.

5. The axial-flow propeller turbine guide vane optimization control device according to claim 1, characterized in that, The connecting rods (4) are all hinged to the ring (1) through the rod pins (9), and several threaded sleeves (15) are threaded on the connecting rods (4).

6. The axial-flow propeller turbine guide vane optimization control device according to claim 5, characterized in that, A guide rail (10) is fixedly connected to the middle section of the ring (1) in the height direction. A detection block (11) is slidably connected to the guide rail (10). A drive component (12) is provided on the detection block (11) to drive the detection block (11) to slide on the guide rail (10). Two laser rangefinders (13) are provided at the bottom of the detection block (11). The laser rangefinders (13) are located on both sides of the detection block (11).

7. The axial-flow propeller turbine guide vane optimization control device according to claim 6, characterized in that, A groove (14) is provided on the connecting rod (4) along the length direction of the connecting rod (4).

8. The axial-flow propeller turbine guide vane optimization control device according to claim 7, characterized in that, The width of the groove (14) is less than 1 / 2 of the width of the connecting rod (4).

9. The axial-flow propeller turbine guide vane optimization control device according to claim 6, characterized in that, The driving component (12) is a roller driven by a motor.

10. The axial-flow propeller turbine guide vane optimization control device according to claim 2, characterized in that, The end of the tension rod (3) near the thrust cylinder (2) is hinged to the piston rod (204) via a heavy-duty joint.

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