A kind of water turbine generator set magnetic yoke outer periphery roundness detection device

Abstract

The utility model discloses a kind of water turbine generator unit magnetic yoke outer periphery roundness detection devices, including horizontal cantilever (1), the middle part of cantilever (1) is equipped with positioning shaft assembly (2), the both ends of cantilever (1) are equipped with slider (3), the below of slider (3) is equipped with the container (4) of top opening, container (4) is filled with liquid damping medium, container (4) is equipped with counterweight (5) immersed in liquid damping medium, counterweight (5) is connected slider (3) by steel wire (6);The positioning shaft assembly (2) includes positioning shaft sleeve (7), the upper end of positioning shaft sleeve (7) is equipped with the positioning protrusion (8) extending radially outward, positioning shaft sleeve (7) is equipped with the rotating shaft (9) of upper end and fixed cantilever (1).The utility model has the advantages of good detection reliability and fast detection speed.

Description

Technical Field

[0001] This utility model belongs to the field of testing devices for hydro-generator sets, and particularly relates to a device for testing the roundness of the outer circumference of the magnetic yoke of a hydro-generator set. Background Technology

[0002] In a hydro-generator unit, there is a certain air gap between the rotor and the stator, and the uniformity of this gap directly affects the safe operation of the unit. The magnetic yoke is a component of the rotor, made up of multiple stacked steel plates. The top of the magnetic yoke has a flange with a central hole, and the outer circumference of the magnetic yoke is coaxial with the central hole.

[0003] Excessive deviation in the outer circumference of the magnetic yoke can lead to uneven clearance between the rotor and stator during rotation. Insufficient clearance in certain areas can cause friction and collision between the rotor and stator (i.e., "stator rubbing"), which can severely damage critical components such as the stator windings and rotor core, and even cause the unit to shut down. Uniform clearance reduces magnetic field distortion, lowers additional losses, and ensures stable electromagnetic conversion efficiency. Furthermore, the magnetic yoke is a crucial component for fixing the magnetic poles; deviation in its outer circumference can cause the rotor's center of gravity to shift, generating unbalanced forces and increasing vibration during unit operation. Therefore, detecting the outer circumference of the magnetic yoke is essential.

[0004] Existing devices for detecting the outer circumference of a magnetic yoke, such as the device and method for accurately measuring the outer diameter of a hydro-generator magnetic yoke as described in application number 202411687075.1, involve connecting a flange to the magnetic yoke via a base. A horizontal measuring arm support is rotatably connected to the base, and a vertical measuring arm is located at the bottom of the measuring arm support. The measuring arm is positioned on the outside of the magnetic yoke. A dial indicator is fixed to the measuring arm, and by moving the dial indicator up and down, multiple vertical distances between the measuring arm and the magnetic yoke at that circumferential position are measured. The measuring arm is rotated by a certain angle, and then multiple vertical distances between the measuring arm and the magnetic yoke at the next circumferential position are measured. This process is repeated until the measuring arm rotates 360°, at which point the measurement ends. The outer circumference of the magnetic yoke is calculated based on the differences in the distribution of these multiple distance data.

[0005] Because there are numerous measurement points but only one measuring arm as a reference, measurements can only be performed by a single person, resulting in slow measurement speed. Furthermore, due to the influence of manufacturing and assembly processes, the verticality of the measuring arm is difficult to guarantee after the existing detection device is installed on the magnetic yoke. The measuring arm itself is prone to large errors, leading to low reliability of the detection results. Utility Model Content

[0006] The purpose of this invention is to provide a device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator set. This invention has the advantages of good detection reliability and fast detection speed.

[0007] The technical solution of this utility model is as follows: a device for detecting the outer circumference of a yoke of a hydro-generator set, comprising a horizontal cantilever, a positioning shaft assembly in the middle of the cantilever, sliders at both ends of the cantilever, a container with a top opening below the sliders, the container being filled with a liquid damping medium, and a counterweight immersed in the liquid damping medium inside the container, the counterweight being connected to the sliders by a steel wire.

[0008] In the aforementioned hydro-generator set magnetic yoke outer circumference detection device, the positioning shaft assembly includes a positioning sleeve, the upper end of which is provided with a positioning protrusion extending radially outward, and the positioning sleeve is provided with a rotating shaft whose upper end is fixed to the cantilever.

[0009] In the aforementioned hydro-generator set magnetic yoke outer circumference detection device, the positioning bushing is connected to the rotating shaft bearing, and a damping sleeve is provided between the positioning bushing and the rotating shaft.

[0010] In the aforementioned hydro-generator set magnetic yoke outer circumference detection device, the slider is screwed with a locking wrench for tightening the cantilever.

[0011] In the aforementioned hydro-generator set magnetic yoke outer circumference detection device, a lead screw is provided above the cantilever. The lead screw is rotatably connected to the cantilever through at least two supports. Both ends of the lead screw are provided with nuts that connect to corresponding sliders. The inner helical directions of the two nuts are opposite.

[0012] In the aforementioned device for detecting the circumference of the magnetic yoke of a hydro-generator set, at least one end of the lead screw is provided with an adjustment handle.

[0013] In the aforementioned device for detecting the circumference of the magnetic yoke of a hydro-generator set, the liquid damping medium is a magnetorheological fluid, and an electromagnetic coil is provided on the outside of the container.

[0014] In the aforementioned hydro-generator set magnetic yoke outer circumference detection device, the bottom of the container is provided with an annular permanent magnet, the permanent magnet is provided with multiple vertical guide holes, the guide holes are provided with guide posts fixed to the container, the bottom of the permanent magnet is provided with an anti-slip plate, the inner side of the permanent magnet is provided with multiple universal casters that are all connected to the container, and the bottom of the container is provided with an elastic body that gives the permanent magnet an upward elastic force.

[0015] In the aforementioned hydro-generator set magnetic yoke outer circumference roundness detection device, the elastic body includes a central plate fixed to the center of the bottom of the container, and a plurality of spring plates extending to the bottom of the permanent magnet are provided on the outer circumference of the central plate.

[0016] Compared with existing technologies, the cantilever of this invention is rotatably connected to the flange at the top of the magnetic yoke via a positioning shaft assembly. By setting steel wires at both ends of the cantilever and counterweights at the lower ends of the steel wires, the weight of the counterweights keeps the steel wires vertical, making them less susceptible to the influence of processing and assembly processes. Using the steel wires as a measurement reference results in a smaller measurement error, thereby improving the reliability of the test results. Furthermore, the testing device has two steel wires, providing two measurement references, allowing for simultaneous measurement by two people, significantly increasing the measurement speed. Therefore, this invention has the advantages of good detection reliability and high detection speed.

[0017] In addition, the upper end of the steel wire is connected to the cantilever via a slider, allowing the steel wire to move horizontally. This adapts to the detection of magnetic yokes with different outer diameters. When the size of the center hole of the top flange of the magnetic yoke changes, only the corresponding positioning bushing needs to be replaced, making the application scope of this utility model wider.

[0018] Two sliders are equipped with nuts with different spiral directions. The two nuts are connected to the same lead screw. By adjusting the handle, the lead screw is rotated, causing the two nuts to move towards each other simultaneously, which in turn moves the two steel wires at the same time, maintaining the same distance from the magnetic yoke. This reduces the debugging time after the detection device is installed on the magnetic yoke and improves the detection speed. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of Example 1.

[0020] Figure 2 yes Figure 1 Enlarged view at point A.

[0021] Figure 3 This is a schematic diagram of the container structure in Example 2.

[0022] Figure 4 This is a bottom-view diagram of a permanent magnet.

[0023] The labels in the attached diagram are as follows: 1-Cantilever, 2-Positioning shaft assembly, 3-Slider, 4-Container, 5-Counterweight, 6-Wire, 7-Positioning bushing, 8-Positioning protrusion, 9-Rotating shaft, 10-Damping sleeve, 11-Locking wrench, 12-Lead screw, 13-Lead nut, 14-Adjusting handle, 15-Electromagnetic coil, 16-Permanent magnet, 17-Guide hole, 18-Guide column, 19-Anti-slip plate, 20-Universal caster, 21-Elastomer, 22-Center plate, 23-Spring plate, 24-Bracket, 25-Magnetic yoke, 26-Support component, 27-Flange. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0025] Example 1: A device for detecting the outer circumference roundness of a hydro-generator yoke is used to detect the outer circumference roundness of the yoke 25 of the hydro-generator. Before detection, the yoke 25 needs to ensure that its axis is vertical. The usual method is to set multiple circumferentially distributed and height-adjustable support members 26 at the bottom of the yoke 25. By adjusting the height of the multiple support members 26, the axial verticality of the yoke 25 can be achieved. The support members 26 can be hydraulic jacks.

[0026] like Figure 1 As shown, the detection device includes a horizontal cantilever 1, with a positioning shaft assembly 2 located in the middle of the cantilever 1. The positioning shaft assembly 2 includes a positioning sleeve 7, with a radially outwardly extending positioning protrusion 8 at the upper end of the positioning sleeve 7. A rotating shaft 9, whose upper end is fixed to the cantilever 1, is located inside the positioning sleeve 7. The positioning sleeve 7 and the rotating shaft 9 are connected by a bearing. A damping sleeve 10, made of rubber, is provided between the positioning sleeve 7 and the rotating shaft 9 to provide an elastic connection, ensuring stable resistance during rotation and preventing accidental rotation. The positioning sleeve 7 mates with the center hole of the top flange 27 of the magnetic yoke 25. The positioning sleeve 7 is inserted into the center hole, and the positioning protrusion 8 is fixed to the flange 27.

[0027] Both ends of the cantilever 1 are equipped with sliders 3, which are symmetrically distributed about the pivot 9. A locking wrench 11 for tightening the cantilever 1 is screwed onto each slider 3. Below each slider 3 is a container 4 with an open top, which is placed on the ground. A common plastic bucket can be used. The container 4 is filled with a liquid damping medium, which is damping oil. A counterweight 5 is immersed in the liquid damping medium inside the container 4. The counterweight 5 is connected to the slider 3 via a steel wire 6. Preferably, the counterweight 5 has multiple blades to increase the contact area with the damping oil. The steel wire 6 is a guitar string, which has the characteristics of rigidity and strength.

[0028] A lead screw 12 is provided above the cantilever 1. Both ends of the lead screw 12 are provided with brackets 24 fixed to the cantilever 1. The lead screw 12 is connected to the brackets 24 by bearings. An adjustment handle 14 fixed to the lead screw 12 is provided on the outside of the brackets 24. Both ends of the lead screw 12 are provided with nuts 13 that connect to the corresponding sliders 3. The nuts 13 are located inside the corresponding brackets 24. The inner helical directions of the two nuts 13 are opposite, and the helical grooves at both ends of the lead screw 12 are opposite. When the lead screw 12 rotates, the two nuts 13 move towards each other.

[0029] Usage method of Example 1: as follows Figure 1As shown, loosen the locking wrench 11, rotate the adjusting handle 14 to change the distance between the two sliders 3, bringing the steel wire 6 closer to the outer circumference of the magnetic yoke 25. Move the container 4 as needed to ensure that the counterweight 5 does not contact the inner wall of the container 4, and then tighten the locking wrench 11. Along the direction of the steel wire 6, set several measuring points in the height direction, and measure the distance between the steel wire 6 and the magnetic yoke 25 at the corresponding measuring points. A micrometer or dial indicator can be used for measuring. Since there are two steel wires 6, two people can perform measurements simultaneously, with two workers simultaneously checking several vertical measuring points at two circumferential positions of the magnetic yoke. Similarly, rotate the cantilever 1 at a certain angle, simultaneously adjusting the position of the container 4, and check several vertical measuring points at the next two circumferential positions of the magnetic yoke. The final data reflects the roundness of multiple cross-sections of the magnetic yoke.

[0030] During the measurement process, since the counterweight 5 is immersed in damping oil, the counterweight 5 is not easy to shake, which keeps the steel wire 6 in a vertical position and does not shake, thereby improving the measurement accuracy.

[0031] Example 2: An improvement to container 4 in Example 1 is made. The liquid damping medium is a magnetorheological fluid, and an electromagnetic coil 15 is provided on the outside of container 4. A ring-shaped permanent magnet 16 is provided at the bottom of container 4. Multiple vertical guide holes 17 are provided on the permanent magnet 16, and guide posts 18 fixed to container 4 are provided within the guide holes 17. A rubber anti-slip plate 19 is provided at the bottom of permanent magnet 16. Multiple universal casters 20, all connected to container 4, are provided on the inner side of permanent magnet 16. An elastic body 21, which provides upward elastic force to permanent magnet 16, is provided at the bottom of container 4. The elastic body 21 includes a central plate 22 fixed to the center of the bottom of container 4. Multiple spring plates 23 extending to the bottom of permanent magnet 16 are provided on the outer periphery of the central plate 22. The spring plates 23 are elastically connected to permanent magnet 16 but not fixed; that is, the outer ends of the spring plates 23 can slide on the bottom surface of permanent magnet 16. The force exerted by the elastic body 21 on permanent magnet 16 is slightly greater than the weight of permanent magnet 16, thus suspending permanent magnet 16.

[0032] How to use container 4: When cantilever 1 needs to rotate, under the action of elastic body 21, permanent magnet 16 does not contact the bottom surface. Because of the universal casters 20 at the bottom of the container, container 4 rolls and connects to the ground, making it easy to move. After container 4 is moved to the designated position, since there is no magnetic field at this time, the magnetorheological fluid has good fluidity, the lateral resistance of counterweight 5 is small, and after counterweight 5 stops swinging, steel wire 6 can maintain a good vertical state, ensuring improved detection accuracy. Subsequently, the electromagnetic coil 15 is energized, generating a strong magnetic field, which serves two purposes. First, it exponentially increases the viscosity of the magnetorheological fluid, bringing it close to a solid state. This makes the steel wire 6 less prone to shaking under a small amount of external force and also helps the counterweight 5 to swing, reducing the waiting time of the steel wire 6 under external force and improving the detection speed. Second, under the influence of the magnetic field, the permanent magnet 16 descends and contacts the ground through the anti-slip plate 19, increasing the contact area between the container 4 and the ground. This improves the anti-slip performance of the container 4, making it less prone to movement under external force and preventing the steel wire 6 from shifting. If a large external force causes the container 4 to move, simply de-energize the electromagnetic coil 15, and the magnetorheological fluid will lose its magnetism and regain its fluidity. Energize again after the counterweight 5 stops swinging.

Claims

1. A device for detecting the roundness of the outer circumference of a yoke in a hydro-generator set, characterized in that: It includes a horizontal cantilever (1), a positioning shaft assembly (2) in the middle of the cantilever (1), sliders (3) at both ends of the cantilever (1), a container (4) with a top opening below the slider (3), the container (4) is filled with liquid damping medium, and a counterweight (5) immersed in the liquid damping medium is provided in the container (4), and the counterweight (5) is connected to the slider (3) by a steel wire (6).

2. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 1, characterized in that: The positioning shaft assembly (2) includes a positioning shaft sleeve (7), the upper end of which is provided with a positioning protrusion (8) extending radially outward, and the positioning shaft sleeve (7) is provided with a rotating shaft (9) whose upper end is fixed to the cantilever (1).

3. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 2, characterized in that: The positioning bushing (7) is connected to the rotating shaft (9) bearing, and a damping sleeve (10) is provided between the positioning bushing (7) and the rotating shaft (9).

4. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 1, characterized in that: A locking wrench (11) for tightening the cantilever (1) is screwed onto the slider (3).

5. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 1, characterized in that: A lead screw (12) is provided above the cantilever (1). The lead screw (12) is rotatably connected to the cantilever (1) through at least two supports (24). Both ends of the lead screw (12) are provided with nuts (13) that connect to the corresponding sliders (3). The inner holes of the two nuts (13) have opposite spiral directions.

6. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 5, characterized in that: At least one end of the lead screw (12) is provided with an adjustment handle (14).

7. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 4, characterized in that: The liquid damping medium is a magnetorheological fluid, and an electromagnetic coil (15) is provided on the outside of the container (4).

8. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 7, characterized in that: The container (4) has an annular permanent magnet (16) at its bottom. The permanent magnet (16) has multiple vertical guide holes (17). The guide holes (17) have guide posts (18) fixed to the container (4) inside. The bottom of the permanent magnet (16) has an anti-slip plate (19). The inner side of the permanent magnet (16) has multiple universal casters (20) that are all connected to the container (4). The bottom of the container (4) has an elastic body (21) that gives the permanent magnet (16) an upward elastic force.

9. The device for detecting the roundness of the outer circumference of the magnetic yoke of a hydro-generator unit according to claim 8, characterized in that: The elastomer (21) includes a central plate (22) fixed to the center of the bottom of the container (4), and the outer periphery of the central plate (22) is provided with a plurality of spring plates (23) extending to the bottom of the permanent magnet (16).

Images