An automatic calibration device for a generator rotor air gap sensor

Abstract

The application provides a kind of generator rotor air gap sensor automatic calibration device, including notebook computer, controller, air gap sensor and calibration device ontology;Air gap sensor is fixedly installed on the wall surface of hydroelectric generator stator, and the metal plate matched with it is installed on the calibration device ontology;Calibration device ontology includes outer frame structure and actuating mechanism, and the actuating mechanism is installed in the outer frame structure, and the actuating mechanism can drive the metal plate to move on the X, Y, Z axis of spatial coordinate system, drive the metal plate to swing and overturn, so that the metal plate is accurately aligned with the air gap sensor.The automatic calibration device can realize the position adjustment of the six degrees of freedom of the metal plate, can satisfy the alignment of the metal plate with the air gap sensor under different generator set stator forms and different calibration site conditions, effectively avoid the calculation and analysis errors caused by manual adjustment, and can simulate the actual working environment of the air gap sensor, and truly reflect the performance of the air gap sensor to be calibrated.

Description

Technical Field

[0001] This invention relates to the field of sensor and instrument calibration technology, and in particular to an automatic calibration device for a generator rotor air gap sensor. Background Technology

[0002] The air gap between the stator and rotor of a hydro-generator is a crucial electromagnetic parameter that directly impacts the generator's operational performance and economic and technical indicators. As the core component of the air gap monitoring system, the performance of the air gap sensor directly affects the accuracy and reliability of the monitoring results. However, due to limitations in installation location and calibration conditions, there is currently no mature equipment in China for on-site calibration of the air gap sensor. Calibration of the air gap sensor is typically performed manually during unit overhauls. This involves pre-fabricating metal plate components with fixed or adjustable support distances, placing these components in front of the air gap sensor's capacitor plate, or manually adjusting the distance between the metal plate component and the capacitor plate, and comparing the deviation between the data displayed by the air gap acquisition system and the fixed support distance to determine the sensor's functionality and performance indicators.

[0003] Current methods and devices for manually adjusting air gap sensors suffer from significant limitations in accuracy due to human error. Furthermore, the measurement errors from manually compiling field test data result in substantial repeatability and linearity errors. The actual operating environment of an air gap sensor involves measuring the air gap between the rotor and stator when the generator rotor rotates at a high speed above 1Hz. Manually moving the measuring metal plate cannot simulate this real-world operating condition. Therefore, it is necessary to design a fully automated air gap sensor calibration device. Summary of the Invention

[0004] In view of the fact that current calibration methods and devices for manually adjusting air gap sensors have poor calibration accuracy and cannot simulate the actual working environment of air gap sensors, this invention provides an automatic calibration device for generator rotor air gap sensors.

[0005] The technical solution adopted in this invention is as follows:

[0006] An automatic calibration device for a generator rotor air gap sensor includes a laptop computer, a controller, an air gap sensor, and a calibration device body.

[0007] The laptop computer's air gap sensor and calibration device body are respectively connected to the controller via a computer communication line, a sensor feedback signal acquisition cable, and a control signal output cable.

[0008] The air gap sensor is fixedly installed on the stator wall of the hydro generator, and the matching metal electrode plate is installed on the body of the calibration device.

[0009] The verification device body includes an outer frame structure and an actuator. The actuator is installed inside the outer frame structure and includes a Y-axis sliding component, a Z-axis displacement component, and an X-axis rotation sliding component. The actuator can drive the metal electrode plate to position and move on the X, Y, and Z axes of the spatial coordinate system, drive the metal electrode plate to swing and flip, so that the metal electrode plate is accurately aligned with the air gap sensor.

[0010] Furthermore, the Y-axis sliding assembly of the spatial coordinate system includes a U-shaped sliding frame, an adjusting screw, and a slide rail;

[0011] The slide rail is symmetrically installed at the top center of the rectangular frame structure along the X-axis of the spatial coordinate system.

[0012] The U-shaped sliding frame has slots on both sides that match the slide rails, and it is slidably installed between the two slide rails;

[0013] The adjusting screw passes through the rectangular frame structure and is threadedly connected to the rectangular frame structure. A handwheel is installed at one end of the screw located outside the rectangular frame structure, and the other end of the screw is rotatably mounted on the U-shaped sliding frame.

[0014] Furthermore, the spatial coordinate system Z-axis displacement assembly includes a gearbox, an active adjustment shaft, a driven locking shaft, a hanger, and a gearbox rotation locking screw;

[0015] The gearbox has mounting shafts extending outward on both sides, which can be rotatably mounted in the U-shaped sliding frame via the mounting shafts.

[0016] The active adjustment shaft and the driven locking shaft pass symmetrically and horizontally through the gearbox and can rotate relative to the gearbox. Adjustment gears are installed on the shafts of both the active adjustment shaft and the driven locking shaft inside the gearbox. There is a gap between the adjustment gear on the active adjustment shaft and the adjustment gear on the driven locking shaft. A handwheel is fixedly installed at the end of the active adjustment shaft outside the gearbox, and a locking handwheel is threadedly installed at the end of the driven locking shaft outside the gearbox.

[0017] The hanger has a U-shaped structure, with a rack fixedly installed at the top center. The rack passes vertically through the gearbox and meshes with the adjusting gears on the active adjusting shaft and the driven locking shaft. The bottom of the hanger is symmetrically provided with hook-shaped bodies that are installed to cooperate with the X-axis rotation sliding assembly of the spatial coordinate system.

[0018] The gearbox rotation locking screws are symmetrically threaded onto the U-shaped sliding frame, and can abut against the mounting shafts on both sides of the gearbox within the U-shaped sliding frame.

[0019] Furthermore, the top of the gearbox is also provided with a mounting base through which the rack passes, and the mounting base is threadedly connected to a hanger locking screw that can pass through the mounting base and abut against the rack.

[0020] Furthermore, the spatial coordinate system X-axis rotation sliding assembly includes a power source mounting box, a power source, and an X-axis telescopic rod;

[0021] The power source mounting box has mounting shafts extending outward on both sides, which can be rotated and mounted on the hook-shaped body at the bottom of the hanger. The mounting shaft is threaded with a locking handwheel that can clamp the hook-shaped body.

[0022] The power source is installed in the power source mounting box and is connected to the controller through a control signal output cable. It passes through the power source mounting box and is connected to the X-axis telescopic rod.

[0023] The X-axis telescopic rod is installed on the top of the power source mounting box, with a metal electrode plate rotatably installed at one end, and a cross laser locator installed at the center of the metal electrode plate.

[0024] Furthermore, the top of the power source mounting box is also equipped with a connecting rod locking screw that can position the X-axis telescopic rod.

[0025] Furthermore, a liquid level and a digital level are also installed on one side of the top of the power source mounting box.

[0026] Furthermore, the power source is a stepper motor or an electric cylinder.

[0027] Furthermore, a strong magnet capable of adsorbing onto the stator wall is installed on one end face of the outer frame structure.

[0028] Furthermore, a lifting ring is provided on one side of the top of the outer frame structure for hoisting purposes.

[0029] The beneficial effects of this invention are:

[0030] Compared with existing technologies, this generator rotor air gap sensor automatic calibration device can adjust the actuator in the outer frame structure to align the metal plate with the air gap sensor, connect the air gap sensor air gap feedback signal to the controller, and start the automatic calibration program in the laptop computer. It can automatically perform calibration error analysis on the air gap sensor to be calibrated, thereby effectively avoiding errors caused by manually adjusting the distance of the metal plate, errors caused by manual reading, and errors caused by manual calculation and analysis.

[0031] The actuator of this generator rotor air gap sensor automatic calibration device can achieve six degrees of freedom position adjustment of the metal plate, which can accurately align the metal plate of the actuator with the air gap sensor under different generator set stator forms and different calibration site conditions. At the same time, the power source of the actuator, together with the controller, can realize high-frequency and rapid back-and-forth movement of the metal plate, simulating the actual working environment of the air gap sensor, that is, measuring the air gap between the rotor and the stator when the generator rotor rotates at a high speed of 1Hz or higher, so as to truly reflect the performance of the air gap sensor to be calibrated. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] in:

[0034] Figure 1 This is a schematic diagram of the overall structure of the automatic calibration device for the generator rotor air gap sensor of the present invention;

[0035] Figures 2 to 7 This is a schematic diagram of the disassembled structure of the verification device body of the present invention;

[0036] Figure 1 —In the diagram, 1—Laptop, 2—Controller, 3—Air gap sensor, 4—Calibration device body, 5—Computer communication cable, 6—Sensor feedback signal acquisition cable, 7—Control signal output cable, 8—Metal electrode plate, 9—Outer frame structure, 10—Y-axis sliding assembly of spatial coordinate system, 11—Z-axis displacement assembly of spatial coordinate system, 12—X-axis rotational sliding assembly of spatial coordinate system, 13—U-shaped sliding frame, 14—Adjusting screw, 15—Slide rail, 16—Handwheel I, 17—Gearbox, 18—Active adjusting shaft, 19— Driven locking shaft, 20—Hanger, 21—Gearbox rotation locking screw, 22—Mounting shaft I, 23—Adjusting gear, 24—Handwheel II, 25—Locking handwheel I, 26—Rack, 27—Hook-like body, 28—Mounting seat, 29—Hanger locking screw, 30—Power source mounting box, 31—Power source, 32—X-axis telescopic rod, 33—Mounting shaft II, 34—Locking handwheel II, 35—Cross laser positioner, 36—Linkage locking screw, 37—Liquid level, 38—Digital level, 39—Strong magnet, 40—Lifting ring. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] The calibration methods and devices for manually adjusting air gap sensors suffer from numerous problems, including the impact of human error on the accuracy of calibration results, measurement errors from manually compiling on-site test data, and significant repeatability and linearity errors. This embodiment provides an automatic calibration device for generator rotor air gap sensors.

[0039] like Figure 1 As shown, the automatic calibration device for the generator rotor air gap sensor includes a laptop computer 1, a controller 2, an air gap sensor 3, and a calibration device body 4. The laptop computer 1 is equipped with an automatic calibration program, specifically the DZ96-08 air gap sensor calibration bench automatic calibration program developed by Chengdu Gaoshen Technology Co., Ltd. The controller 2 uses the SDDZ-08 air gap sensor calibration device product from Chengdu Gaoshen Technology Co., Ltd. The laptop computer 1 is connected to the controller 2 via a computer communication cable 5. The air gap sensor 3 uses a VibroSys™ VM5.0 air gap sensor from Canada as the measuring element, and the TN8000STA hydro-generator stability analysis system from Beijing Huake Tongan Monitoring Technology Co., Ltd. is used as the display device. The air gap sensor 3 is fixedly installed on the stator wall of the hydro-generator and connected to the controller 2 via a sensor feedback signal acquisition cable 6. A metal electrode plate 8, matching the air gap sensor 3, is installed on the calibration device body 4.

[0040] The calibration device body 4 can be installed on the stator wall of the hydro generator. The calibration device body 4 includes an outer frame structure 9 and an actuator. The actuator is installed inside the outer frame structure 9. The actuator can drive the metal electrode plate 8 to be positioned and moved on the X, Y, and Z axes of the spatial coordinate system, and drive the metal electrode plate 8 to swing and flip, so that the metal electrode plate 8 is accurately aligned with the air gap sensor 3.

[0041] Furthermore, in order to provide a detailed explanation of the actuator's structure and how it drives the metal electrode plate 8 to achieve various positional adjustments, the following detailed explanation is provided:

[0042] Since the actuator needs to adjust the metal electrode plate 8 in multiple positions, this embodiment designs the actuator based on a spatial rectangular coordinate system. Specifically, it consists of a spatial coordinate system Y-axis sliding component 10, a spatial coordinate system Z-axis displacement component 11, and a spatial coordinate system X-axis rotational sliding component 12. The spatial coordinate system Y-axis sliding component 10 is mounted on the outer frame structure 9, the spatial coordinate system Z-axis displacement component 11 is mounted on the spatial coordinate system Y-axis sliding component 10, and the spatial coordinate system X-axis rotational sliding component 12 is mounted at the bottom of the spatial coordinate system Z-axis displacement component 11, located inside the outer frame structure 9. The metal electrode plate 8 is mounted on the spatial coordinate system X-axis rotational sliding component 12.

[0043] Structure of the Y-axis sliding component 10 in the spatial coordinate system:

[0044] like Figure 2 and Figure 3 As shown, the Y-axis sliding assembly 10 of the spatial coordinate system includes a U-shaped sliding frame 13, an adjusting screw 14, and slide rails 15. There are two slide rails 15, symmetrically installed at the top center of the rectangular frame structure along the X-axis of the spatial coordinate system. The U-shaped sliding frame 13 has slots on both sides to accommodate the slide rails 15, allowing it to slide between the two slide rails 15. The U-shaped sliding frame 13 serves as the base for the Z-axis displacement assembly 11 of the spatial coordinate system. The adjusting screw 14 passes through the rectangular frame structure and is threadedly connected to it. A handwheel I 16 is installed at one end of the adjusting screw 14 located outside the rectangular frame structure, and the other end is rotatably mounted on the U-shaped sliding frame 13.

[0045] Position adjustment function of Y-axis sliding component 10 in spatial coordinate system:

[0046] The first degree of freedom of the actuator is formed by the X-axis sliding component in conjunction with the outer frame structure 9, such as... Figure 2 As shown in the spatial coordinate system, by rotating the handwheel I16 in both directions, the adjusting screw 14 rotates relative to the outer frame structure 9. Since the adjusting screw 14 is threadedly connected to the rectangular frame structure, it can push or pull the U-shaped sliding frame 13 to slide on the two slide rails 15, so that the spatial coordinate system Z-axis displacement component 11, the spatial coordinate system X-axis rotation sliding component 12, and the metal pole plate 8 are positioned and moved on the Y-axis of the spatial coordinate system.

[0047] Structure of the Z-axis displacement component 11 in the spatial coordinate system:

[0048] like Figure 4 , Figure 5 and Figure 6As shown, the spatial coordinate system Z-axis displacement assembly 11 is installed within the U-shaped sliding frame 13 and extends along the Z-axis direction of the spatial coordinate system. The spatial coordinate system Z-axis displacement assembly 11 includes a gearbox 17, an active adjustment shaft 18, a driven locking shaft 19, a hanger 20, and a gearbox rotation locking screw 21. Mounting shafts I 22 extend outward from both sides of the gearbox 17, allowing the gearbox 17 to be rotatably mounted within the U-shaped sliding frame 13 via the two mounting shafts I 22. The active adjusting shaft 18 and the driven locking shaft 19 pass symmetrically and horizontally through the gearbox 17 and are rotatable relative to the gearbox 17. Adjusting gears 23 are mounted on the shafts of both the active adjusting shaft 18 and the driven locking shaft 19 within the gearbox 17. A gap is left between the adjusting gears 23 on the active adjusting shaft 18 and the driven locking shaft 19. A handwheel II 24 is fixedly mounted on the end of the active adjusting shaft 18 outside the gearbox 17, and a locking handwheel I 25 is threadedly mounted on the end of the driven locking shaft 19 outside the gearbox 17. The hanger 20 has a U-shaped structure. A rack 26 is fixedly mounted at the middle of the top of the hanger 20. The rack 26 passes vertically through the gearbox 17 and meshes with the adjusting gears 23 on the active adjusting shaft 18 and the driven locking shaft 19. Hook-shaped bodies 27 are symmetrically provided at the bottom of the hanger 20 to cooperate with the X-axis rotation sliding assembly 12 of the spatial coordinate system. The gearbox rotation locking screw 21 is symmetrically threaded onto the U-shaped sliding frame 13, and the gearbox rotation locking screw 21 can abut against the mounting shaft I 22 on both sides of the gearbox 17 inside the U-shaped sliding frame 13.

[0049] Position adjustment function of Z-axis displacement component 11 in spatial coordinate system:

[0050] First, the gearbox 17 of the Z-axis displacement assembly 11 in the spatial coordinate system, together with the U-shaped sliding frame 13, constitutes the second degree of freedom of the actuator; such as Figure 2 and Figure 4 As shown, since the gearbox 17 can be rotatably mounted in the U-shaped sliding frame 13 via two mounting shafts I 22, the gearbox 17 can drive the hanger 20, the X-axis rotation sliding assembly 12 of the spatial coordinate system, and the metal pole plate 8 to swing and adjust the angle relative to the U-shaped sliding frame 13 and the outer frame structure 9, and the swing angle is positioned by the gearbox rotation locking screw 21.

[0051] Secondly, the adjusting gear 23 inside the gearbox 17, together with the rack 26 on the top of the hanger 20, constitutes the third degree of freedom of the actuator. By rotating the handwheel II 24 in both directions, the active adjusting shaft 18 drives the adjusting gear 23 on the active adjusting shaft 18 to rotate inside the gearbox 17. Since the adjusting gear 23 on the active adjusting shaft 18 meshes with the rack 26 on the top of the hanger 20, the rack 26 can move relative to the gearbox 17 on the Z-axis of the spatial coordinate system, thereby driving the X-axis rotation sliding assembly 12 and the metal pole plate 8 to rise and fall within the outer frame structure 9. When it is necessary to position this degree of freedom, the locking handwheel I 25, which is threaded onto the driven locking shaft 19, can be rotated to abut against the outer wall of the gearbox 17, thereby creating resistance to the rotation of the driven locking shaft 19. Thus, the position of the rack 26 is positioned by the adjusting gear 23 on the driven locking shaft 19 that meshes with the rack 26.

[0052] Furthermore, such as Figure 4 and Figure 5 As shown, in this embodiment, a mounting base 28 is provided on the top of the gearbox 17 to allow the rack 26 to pass through, and a hanger locking screw 29 that can pass through the mounting base 28 and abut against the rack 26 is threaded onto the mounting base 28 to further position the rack 26.

[0053] Structure of the X-axis rotation sliding component 12 in the spatial coordinate system:

[0054] like Figure 1 and Figure 6 As shown, the X-axis rotation sliding assembly 12 of the spatial coordinate system is mounted on the hanger 20 via hook-shaped bodies 27 symmetrically arranged at the bottom of the hanger 20; as Figure 7 As shown, the X-axis rotation sliding assembly 12 of the spatial coordinate system includes a power source mounting box 30, a power source 31, and an X-axis telescopic rod 32. The power source mounting box 30 has mounting shafts II 33 extending outwards from both sides. The power source mounting box 30 is rotatably mounted on a hook-shaped body 27 at the bottom of the hanger 20 via the mounting shafts II 33. A locking handwheel II 34, capable of clamping the hook-shaped body 27, is threaded onto the mounting shafts II 33. The power source 31 is installed inside the power source mounting box 30 and connected to the controller 2 via a control signal output cable 7. The power source 31 passes through the power source mounting box 30 and is connected to the X-axis telescopic rod 32 via a transmission connection. The X-axis telescopic rod 32 is mounted on the top of the power source mounting box 30, with a metal electrode plate 8 rotatably mounted at one end. A cross laser locator 35 is mounted at the center of the metal electrode plate 8.

[0055] This embodiment provides two power source methods. Method 1: The power source 31 adopts a stepper motor, which is connected to the X-axis telescopic rod 32 through a gear mechanism to form a ball screw jack structure, thereby satisfying the telescopic movement of the X-axis telescopic rod 32 relative to the power source mounting box 30. Method 2: The power source 31 adopts an electric cylinder, the cylinder body is installed in the power source mounting box 30, and the X-axis telescopic rod 32 is the telescopic rod of the electric cylinder.

[0056] Position adjustment function of the X-axis rotation sliding component 12 in the spatial coordinate system:

[0057] First, the mounting shafts II 33 extending outwards on both sides of the power source mounting box 30, together with the hook-shaped body 27 at the bottom of the hanger 20, constitute the fourth degree of freedom of the actuator. The power source mounting box 30, through the mounting shafts II 33, can drive the X-axis telescopic rod 32 and the metal electrode plate 8 to rotate relative to the hanger 20, and the rotation angle is positioned by clamping the hook-shaped body 27 with the locking handwheel II 34. Second, the power source 31, together with the X-axis telescopic rod 32, constitutes the fifth degree of freedom of the actuator. Since the power source 31 is connected to the controller 2 through the control signal output cable 7, the controller 2 controls the operation of the power source 31, causing the X-axis telescopic rod 32 to drive the metal electrode plate 8 to move and extend relative to the power source mounting box 30. Furthermore, the metal electrode plate 8 is rotatably mounted at the end of the X-axis telescopic rod 32, and can rotate relative to the X-axis telescopic rod 32, thus constituting the sixth degree of freedom of the actuator. Further, to prevent the X-axis telescopic rod 32 from moving when the power source 31 is not activated, such as... Figure 7 As shown, the top of the power source mounting box 30 is also equipped with a connecting rod locking screw 36 that can position the X-axis telescopic rod 32.

[0058] Based on the detailed structure and position adjustment function of the above actuator, the following operations can be performed when calibrating the air gap sensor 3 on site:

[0059] The on-site verification device body 4 is transported to the vicinity of the stator wall of the hydro-generator, and the air gap sensor 3 is fixedly installed on the stator wall. The outer frame structure 9 is moved to initially align the metal electrode plate 8 with the air gap sensor 3 to be verified. Then, the cross laser positioner 35 is turned on to prepare for subsequent precise adjustment, guiding the precise adjustment of the metal electrode plate 8. The precise adjustment of the metal electrode plate 8 is carried out through the aforementioned six degrees of freedom position adjustment and corresponding positioning, so that the metal electrode plate 8 is accurately aligned with and close to the air gap sensor 3 to be verified. Since the X-axis rotation sliding assembly of the actuator ultimately needs to be aligned with the air gap sensor 3 in a horizontal posture to ensure that the extension and retraction movement of the X-axis telescopic rod 32 driven by the power source 31 can simulate the actual working environment of the air gap sensor 3, therefore, as Figure 7 As shown, in this embodiment, a liquid level 37 and a digital level 38 are also installed on one side of the top of the power source mounting box 30.

[0060] After the position adjustment of the actuator and outer frame structure 9 is completed, and the metal electrode plate 8 is positioned, the control signal output cable 7 between the actuator and the controller 2 is connected, and the computer communication cable 5 between the controller 2 and the laptop 1 is connected. The feedback signal from the air gap sensor 3 is connected back to the corresponding input terminal of the controller 2 through the sensor feedback signal acquisition cable 6. The power cord is turned on, and the equipment start-up verification program is started to complete the automatic verification process of the generator rotor air gap sensor, obtaining the automatic verification result of the air gap sensor. The verification program can set the number of automatic sampling points, the travel distance of the metal electrode plate 8, and the movement frequency of the metal electrode plate 8. The forward and return movement frequencies of the metal electrode plate 8 are set according to the power source 31, which can simulate the actual working environment of the air gap sensor.

[0061] Because the on-site calibration of the air gap sensor requires manual handling and securing of the external frame structure 9, therefore, as Figure 1 As shown, in this embodiment, three sets of strong magnets 39 capable of adsorbing onto the stator wall are installed on one end face of the outer frame structure 9. The strong magnets 39 enable the outer frame structure 9 to adhere to the stator wall of the hydro-generator. Simultaneously, in this embodiment, a lifting ring 40 is provided on one side of the top of the outer frame structure 9 for hoisting, allowing the outer frame structure 9 to be hoisted and transported, and preventing the actuator 2 and the outer frame structure 9 from accidentally falling and being damaged during the calibration process.

[0062] To verify the effectiveness of the automatic calibration device for the generator rotor air gap sensor, this embodiment compares the automatic calibration results obtained by the automatic calibration device with the automatic calibration results obtained by a manually adjusted calibration method and device.

[0063] The automatic verification results of the air gap sensor obtained by the automatic verification device of the generator rotor air gap sensor are shown in Table 8. The automatic verification results of the air gap sensor obtained by the manually adjusted verification method and verification device are shown in Table 9.

[0064] Table 8 Automatic Calibration Results of Air Gap Sensors

[0065]

[0066] Table 9. Verification Results of Manually Adjusted Verification Methods

[0067] Air gap acquisition system displays data (mm) 5.4 10.6 14.7 18.9 25.6 Relative error (%) 8％ 6％ -2％ -6％ 2％

[0068] As can be seen from the comparison in Tables 8 and 9, the automatic calibration device for the generator rotor air gap sensor effectively avoids errors caused by manual adjustment of the metal plate distance, errors caused by manual reading, and errors caused by manual calculation and analysis. The resulting automatic calibration results for the air gap sensor are more accurate. The metal plates of the automatic calibration device can move back and forth rapidly at high frequency. Specifically, when the generator's rated speed is 125 r / min and the rotor is rotating at a high speed of 0.48 s / r, the metal plates of the automatic calibration device can move from a 5 mm position to a 25 mm position within 0.48 s, simulating the actual working environment of the air gap sensor and truly reflecting the performance of the air gap sensor to be calibrated.

[0069] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A generator rotor air gap sensor auto-checking device, characterized by: The automatic calibration device for the generator rotor air gap sensor includes a laptop computer, a controller, an air gap sensor, and the calibration device body. The laptop computer's air gap sensor and calibration device body are respectively connected to the controller via a computer communication line, a sensor feedback signal acquisition cable, and a control signal output cable. The air gap sensor is fixedly installed on the stator wall of the hydro generator, and the matching metal electrode plate is installed on the body of the calibration device. The verification device body includes an outer frame structure and an actuator. The actuator is installed inside the outer frame structure. The actuator includes a Y-axis sliding component, a Z-axis displacement component, and an X-axis rotation sliding component. The actuator can drive the metal plate to be positioned and moved on the X, Y, and Z axes of the spatial coordinate system, and drive the metal plate to swing and flip, so that the metal plate is accurately aligned with the air gap sensor. The Y-axis sliding assembly of the spatial coordinate system includes a U-shaped sliding frame, an adjusting screw, and a slide rail. The slide rail is symmetrically installed at the top center of the rectangular outer frame structure along the X-axis of the spatial coordinate system. The U-shaped sliding frame has slots on both sides to fit the slide rail, and it is slidably installed between the two slide rails. The adjusting screw passes through the rectangular outer frame structure and is threadedly connected to the rectangular outer frame structure. A handwheel is installed at one end of the adjusting screw located outside the rectangular outer frame structure, and the other end of the adjusting screw is rotatably installed on the U-shaped sliding frame. The spatial coordinate system Z-axis displacement assembly includes a gearbox, an active adjusting shaft, a driven locking shaft, a hanger, and a gearbox rotation locking screw. The gearbox has mounting shafts extending outwards on both sides, allowing it to be rotatably mounted within a U-shaped sliding frame. The active adjusting shaft and the driven locking shaft symmetrically and horizontally pass through the gearbox and are rotatable relative to it. Adjusting gears are mounted on the shafts of both the active adjusting shaft and the driven locking shaft within the gearbox. A gap is maintained between the adjusting gear on the active adjusting shaft and the adjusting gear on the driven locking shaft. A handwheel is fixedly installed at the end of the active adjustment shaft outside the gearbox, and a locking handwheel is threadedly installed at the end of the driven locking shaft outside the gearbox. The hanger has a U-shaped structure, with a rack fixedly installed at the middle of its top. The rack passes vertically through the gearbox and meshes with the adjustment gears on the active adjustment shaft and the driven locking shaft. The bottom of the hanger is symmetrically provided with hook-shaped bodies that cooperate with the X-axis rotation sliding assembly of the spatial coordinate system. The gearbox rotation locking screw is symmetrically threaded on the U-shaped sliding frame, and it can abut against the mounting shafts on both sides of the gearbox inside the U-shaped sliding frame.

2. The automatic calibration device for generator rotor air gap sensor according to claim 1, characterized in that: The top of the gearbox is also provided with a mounting base through which the rack passes, and the mounting base is threadedly connected to a hanger locking screw that can pass through the mounting base and abut against the rack.

3. The automatic calibration device for generator rotor air gap sensor according to claim 1, characterized in that: The spatial coordinate system X-axis rotation sliding assembly includes a power source mounting box, a power source, and an X-axis telescopic rod; The power source mounting box has mounting shafts extending outward on both sides, which can be rotated and mounted on the hook-shaped body at the bottom of the hanger. A locking handwheel that can clamp the hook-shaped body is threaded onto the mounting shaft. The power source is installed in the power source mounting box and is connected to the controller through a control signal output cable. It passes through the power source mounting box and is connected to the X-axis telescopic rod. The X-axis telescopic rod is installed on the top of the power source mounting box, with a metal electrode plate rotatably installed at one end, and a cross laser locator installed at the center of the metal electrode plate.

4. The automatic calibration device for generator rotor air gap sensor according to claim 3, characterized in that: The top of the power source mounting box is also equipped with a connecting rod locking screw that can position the X-axis telescopic rod.

5. The automatic calibration device for generator rotor air gap sensor according to claim 3, characterized in that: A liquid level and a digital level are also installed on one side of the top of the power source mounting box.

6. The automatic calibration device for generator rotor air gap sensor according to claim 3, characterized in that: The power source is a stepper motor or an electric cylinder.

7. The automatic calibration device for generator rotor air gap sensor according to claim 1, characterized in that: A strong magnet capable of adsorbing onto the stator wall is installed on one end face of the outer frame structure.

8. The automatic calibration device for generator rotor air gap sensor according to claim 1, characterized in that: The top side of the outer frame structure is equipped with a lifting ring for hoisting.

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