A real-time diagnosis method and device for large-scale steam turbines in thermal power plants

Abstract

This invention discloses a method and device for real-time diagnosis of large rotating turbines in thermal power plants. To facilitate real-time vibration diagnosis of inaccessible high-level parts of the turbine by inspection personnel, an electrically operated lifting structure is specifically designed for use with a drone gimbal camera. The lifting structure includes a load box, and a magnetic vibration sensor is mounted below the load box via a vertical connecting rod, allowing for direct delivery of the vibration sensor to the area to be inspected on the turbine. This invention enables the delivery of magnetically attracted vibration sensors to large rotating turbines via drones, facilitating real-time vibration diagnosis of high-level parts of the turbine that are difficult for inspection personnel to reach. Simultaneously, a spiral vibration isolation sleeve is nested at the end of the connecting wire of the magnetic vibration sensor near the load box, effectively blocking vibration transmitted between the load box and the magnetic vibration sensor through the connecting wire, thus realizing the feasibility of drone-delivered magnetic vibration sensors.

Description

Technical Field

[0001] This invention relates to the technical field of diagnostics of large-scale rotating units in thermal power plants, and particularly to a method and apparatus for real-time diagnostics of large-scale rotating units in thermal power plants. Background Technology

[0002] In thermal power plants, rotating equipment mainly consists of fans, pumps, and coal mills. Large rotating units mainly include forced draft fans, induced draft fans, pulverized coal exhaust fans, feedwater pumps, circulating water pumps, condensate pumps, coal mills, ash slurry pumps, slag slurry pumps, and high-pressure flushing water pumps. A malfunction can affect unit operation and even lead to unit shutdown. When a fault occurs and maintenance is required, the time and cost are high. Therefore, it is essential to conduct real-time diagnostics on these large turbines. Currently, real-time diagnostics generally rely on installing vibration sensors on these large turbines to monitor vibrations during operation. Based on these monitoring results, the operation center diagnoses whether a fault has occurred. In addition, power plants also arrange for inspection personnel to conduct regular inspections of these large turbines. During the inspections, the inspection personnel carry vibration testing instruments for detection and diagnosis. However, for large turbines, certain high positions that are difficult for inspection personnel to reach become blind spots. The operation center determines that a fault occurs in the high part of the large turbine by relying on sensors pre-installed at the high position. However, a decrease in the monitoring accuracy of these sensors can lead to false alarms at the operation center. In this case, a more reliable approach is for inspection personnel to go to the location and conduct on-site real-time diagnostics to determine whether the problem lies with the pre-installed sensors or with the faulty part of the turbine. To address this, we have designed a real-time diagnostic device based on existing drone technology, which avoids the cumbersome climbing of the turbine's external supports by inspection personnel and effectively improves their personal safety. Summary of the Invention

[0003] To address the existing problems mentioned above, this invention provides a method and device for real-time diagnosis of large rotating turbines in thermal power plants. To facilitate real-time vibration diagnosis of hard-to-reach parts of the rotating turbines by inspection personnel, an electric lifting structure that can be used in conjunction with a drone gimbal camera is specially designed. The electric lifting structure is equipped with a load box, and a magnetic vibration sensor is installed below the load box via a vertical connecting rod, which facilitates the direct delivery of the vibration sensor to the part of the rotating turbine to be inspected for real-time vibration diagnosis.

[0004] The technical solution of this invention is as follows:

[0005] This invention provides a real-time diagnostic method for large-scale rotating units in thermal power plants, comprising the following steps:

[0006] S1. The inspection personnel remotely control the drone to fly to the high part of the large rotating machine that generates an abnormal alarm at the inspection site, observe and determine the specific location through the drone's gimbal camera, and control the drone to hover above that location.

[0007] S2. A load cell extends downward from the end of the gimbal camera away from the camera, and a magnetic vibration sensor connected to the load cell via a vertical connecting rod extends downward from the drone landing gear.

[0008] S3. The remote control load box powers on the magnetic vibration sensor, which magnetically attaches to the part to be detected on the rotating machine and detaches from the lower end of the vertical connecting rod.

[0009] S4. The inspection personnel use a handheld control terminal to determine in real time whether the abnormality is due to a problem with the pre-installed sensor or a fault in the corresponding part of the device, based on the data wirelessly transmitted by the magnetic vibration sensor through the controller in the load box. The real-time diagnostic results are then fed back to the operation center, which decides on the next steps.

[0010] Furthermore, one side of the magnetic vibration sensor is detachably snapped onto the lower end of the vertical connecting rod.

[0011] Furthermore, the magnetic vibration sensor includes an electromagnet and a vibration sensor, with the electromagnet nested at the lower end of the vibration sensor, and the connecting wires of the electromagnet and the vibration sensor being electrically connected to the controller inside the load box.

[0012] This invention also provides a real-time diagnostic device for large rotating units in thermal power plants, comprising a support base, an electrically telescopic structure, a load box, a vertical connecting rod, a spiral vibration isolation sleeve, a connecting sleeve, and a magnetic vibration sensor. The support base is used to mount on the end of a drone gimbal camera away from the camera. The support base is provided with a vertically downward electrically telescopic structure, and the electrically telescopic structure is provided with a load box that can be moved up and down by the electrically telescopic structure. The lower end of the load box is provided with a vertically downward extending vertical connecting rod, and the lower end of the vertical connecting rod is detachably snapped with a connecting sleeve. A magnetic vibration sensor is locked onto the connecting sleeve. The end of the connecting wire of the magnetic vibration sensor near the load box is nested with a spiral vibration isolation sleeve for blocking the vibration transmitted between the load box and the magnetic vibration sensor through the connecting wire. The spiral vibration isolation sleeve is made of a rigid elastic material and extends downward in a spiral. The upper end of the spiral vibration isolation sleeve is fixedly mounted on the lower end surface of the load box.

[0013] Furthermore, the magnetic vibration sensor includes an electromagnet and a vibration sensor, with the electromagnet nested at the lower end of the vibration sensor, and the connecting wires of the electromagnet and the vibration sensor being electrically connected to the controller inside the load box.

[0014] Furthermore, the load box is equipped with a controller and a power supply. The power supply can power the controller, electromagnet and vibration sensor. The controller can wirelessly communicate with the control terminal of the on-site inspection personnel.

[0015] Furthermore, the load box is also equipped with a second servo motor connected to the vertical connecting rod. The side of the second servo motor is abutted by a vertically extending limit rod used to restrict the planar movement of the second servo motor. A threaded sleeve that is helically nested on the upper end of the vertical connecting rod is fixedly provided on the lower end surface of the load box. The upper end of the vertical connecting rod is provided with an externally threaded threaded section to form a threaded connection with the threaded sleeve.

[0016] Furthermore, an annular groove is provided on the outer wall of the lower end of the vertical connecting rod, and a detachable sleeve is provided on the connecting sleeve corresponding to the connecting groove for elastically nesting on the vertical connecting rod, so that the magnetic vibration sensor can be hung on the vertical connecting rod when it is not magnetically attached to the part to be detected on the rotating machine.

[0017] Furthermore, the electric telescopic structure includes a first servo motor, a right-angle reducer, a lead screw, a guide rod, and a connecting plate. The first servo motor and the right-angle reducer are connected together and respectively mounted on the support base. The output end of the right-angle reducer is connected to the lead screw hinged to the support base. The lead screw extends vertically downward from the support base and has a connecting plate hinged to its lower end. A guide rod is fixedly mounted on the connecting plate and the support base. The load box is nested on the lead screw and the guide rod and is threadedly connected to the lead screw.

[0018] Furthermore, with the load box moved downwards by the lead screw to the lower end of the lead screw, the upper end of the magnetic vibration sensor is lower than the lower end of the UAV's landing gear.

[0019] Because the present invention employs the above-mentioned technology, its specific positive and beneficial effects compared with the prior art are as follows:

[0020] 1. In order to facilitate real-time vibration diagnosis of parts of the rotating machine that are difficult for inspection personnel to reach at high levels, this invention is specially designed with an electric lifting structure that can be used in conjunction with a drone gimbal camera. The electric lifting structure is equipped with a load box, and a magnetic vibration sensor is installed below the load box via a vertical connecting rod. The vibration sensor can be directly delivered to the part of the rotating machine to be inspected, so that the inspection personnel can diagnose in real time on-site whether the problem is caused by a pre-installed sensor or a fault in that part of the rotating machine.

[0021] 2. To avoid the large size of the magnetic vibration sensor after adding a controller and power supply, which would affect the vibration detection accuracy, this invention includes an electromagnet and a vibration sensor. The electromagnet and vibration sensor are connected to the load box above via a connecting line. The end of the connecting line near the load box is nested with a spiral vibration isolation sleeve, which can effectively block the vibration transmitted between the load box and the magnetic vibration sensor through the connecting line. This makes it feasible for the drone to deliver the magnetic vibration sensor. This avoids the downward transmission of vibrations that would affect the detection accuracy of the vibration sensor by the hovering drone, and also avoids the rigid connection between the magnetic vibration sensor and the hovering drone, which would affect the hovering stability of the drone. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the UAV diagnostic structure of the present invention in a contracted state;

[0023] Figure 2 yes Figure 1 Right view of the structure shown;

[0024] Figure 3 This is a schematic diagram of the UAV diagnostic structure of the present invention in its extended state;

[0025] Figure 4 yes Figure 3 Right view of the structure shown;

[0026] Figure 5 This is a schematic diagram of the structure of the diagnostic device of the present invention;

[0027] Figure 6 yes Figure 5 A magnified view of a portion of point A in the middle;

[0028] Figure 7 yes Figure 5 Top view of the structure shown;

[0029] Figure 8 yes Figure 5 Left view of the structure shown;

[0030] Figure 9 yes Figure 5 This is a schematic diagram of the retractable lever structure in the diagnostic device of the present invention;

[0031] Figure 10 yes Figure 9 A cross-sectional view of the structure shown.

[0032] In the diagram: 1-arm, 2-body, 3-landing gear, 4-first servo motor, 5-bearing plate, 6-load box, 7-pan-tilt camera, 8-first spiral vibration isolation sleeve, 9-optical bar, 10-connecting plate, 11-vertical connecting rod, 12-power supply line, 13-electromagnet, 14-vibration sensor, 15-jointing sleeve, 16-detection line, 17-lead screw, 18-second spiral vibration isolation sleeve, 19-right angle reducer, 20-pan-tilt connecting plate, 21-jointing groove, 22-detachable sleeve, 23-threaded section, 24-limiting rod, 25-second servo motor, 26-threaded sleeve. Detailed Implementation

[0033] Example 1:

[0034] like Figures 1-10 As shown, this invention also provides a real-time diagnostic device for large rotating turbines in thermal power plants. Based on existing UAV technology, it mainly includes a UAV, a gimbal camera, a support base, an electrically telescopic structure, a load box 6, a vertical connecting rod 11, a spiral vibration isolation sleeve, a connecting sleeve 15, and a magnetic vibration sensor 14. The lower end of the UAV is equipped with a gimbal camera. A support base is located on the end of the gimbal camera away from the camera, which is the arm portion where the gimbal and UAV are hinged. This ensures that the support base does not affect the rotation of the gimbal relative to the UAV, nor does it affect the up-and-down swing of the camera. The support base includes a support plate 5 for mounting the electrically telescopic structure and a gimbal connecting plate 20 for connecting to the gimbal. An electrically telescopic structure is provided on the support base, and a load box 6, which can be driven to move up and down by the electrically telescopic structure, is provided on the electrically telescopic structure. A vertically extending vertical connecting rod 11 is located at the lower end of the load box 6. The lower end of the connecting rod 11 is detachably snapped with a coupling sleeve 15, and a magnetic vibration sensor 14 is locked onto the coupling sleeve 15. The end of the connecting wire of the magnetic vibration sensor 14 near the load box 6 is nested with a spiral vibration isolation sleeve to block the vibration transmitted between the load box 6 and the magnetic vibration sensor 14 through the connecting wire. The spiral vibration isolation sleeve is made of hard elastic materials such as spring steel and plastic and extends downward spirally. The spiral vibration isolation sleeve is a spirally extended tubular structure and has a notch on the outside along the spiral line for the connecting wire to be inserted. The upper end of the spiral vibration isolation sleeve is fixedly set on the lower end surface of the load box 6. At the same time, when the load box 6 is moved downward to the lower end of the lead screw 17 driven by the lead screw 17, the upper end of the magnetic vibration sensor 14 should be lower than the lower end of the landing gear 3 of the UAV to avoid the UAV landing gear 3 affecting the magnetic vibration sensor 14 to be attracted to the detection part of the rotating machine.

[0035] The magnetic vibration sensor 14 includes an electromagnet 13 and a vibration sensor 14. The electromagnet 13 is nested at the lower end of the vibration sensor 14. The connecting lines of the electromagnet 13 and the vibration sensor 14 are a power supply line 12 and a detection line 16, respectively. The spiral vibration isolation sleeve includes a first spiral vibration isolation sleeve 8 corresponding to the power supply line 12 and a second spiral vibration isolation sleeve 18 corresponding to the detection line 16. The upper ends of the first spiral vibration isolation sleeve 8 and the second spiral vibration isolation sleeve 18 are respectively fixedly installed on the left and right sides of the lower end face of the load box 6. That is, the first spiral vibration isolation sleeve 8 and the second spiral vibration isolation sleeve 18 extend spirally downward on the left and right sides of the vertical connecting rod 11. The power supply line 12 and the detection line 16 are electrically connected to the controller in the load box 6. The load box 6 is equipped with a microcontroller controller and a power supply. The power supply can supply power to the microcontroller controller, the electromagnet 13 and the vibration sensor 14. The microcontroller controller has a wireless communication module and can wirelessly interact with the control terminal of the on-site inspection personnel.

[0036] Typically, when a drone hovers approximately 100mm above the rotating part to be tested, the magnetic vibration sensor 14 suddenly magnetically attaches downwards to the rotating part, causing a significant downward pull on the drone, which severely affects its flight stability. To further improve the stability of the magnetic vibration sensor 14 as it lands on the rotating part to be tested, a second servo motor 25 connected to the vertical connecting rod 11 is installed inside the load box 6. A vertically extending limit rod 24, which restricts the planar movement of the second servo motor 25, is attached to the side of the second servo motor 25. A threaded sleeve 26, spirally nested on the upper end of the vertical connecting rod 11, is fixedly installed on the lower end face of the load box 6. The upper end of the vertical connecting rod 11 has an externally threaded section 23 to form a threaded connection with the threaded sleeve 26. Thus, when the drone hovers above the rotating part to be tested, the electric telescopic structure first drives the load... The load box 6 moves downwards with the magnetic vibration sensor 14. When the load box 6 reaches its lowest position, the second servo motor 25 drives the threaded section 23 of the vertical connecting rod 11 to rotate relative to the threaded sleeve 26, causing the vertical connecting rod 11 to move downwards until the inspector observes through the camera that the electromagnet 13 is about to touch the part to be tested on the rotating machine. At this point, the magnetic vibration sensor 14 is finely adjusted downwards. In this way, the electromagnet 13 is energized and the second servo motor 25 is synchronously controlled to drive the vertical connecting rod 11 upwards. After the electromagnet 13 is magnetically attracted to the part to be tested on the rotating machine, the vertical connecting rod 11 and the connecting sleeve 15 are also separated synchronously. The connecting wire of the magnetic vibration sensor 14 is secured by the spiral vibration isolation sleeve. This minimizes the interaction between the UAV and the magnetic vibration sensor 14, effectively ensuring the hovering stability of the UAV.

[0037] The detachable connection between the vertical connecting rod 11 and the connecting sleeve 15 is achieved by providing an annular groove 21 on the lower outer wall of the vertical connecting rod 11 and a detachable sleeve 22 on the connecting sleeve 15 corresponding to the connecting groove 21 for elastically nesting on the vertical connecting rod 11. This allows the magnetic vibration sensor 14 to be hung on the vertical connecting rod 11 when it is not magnetically attached to the part to be detected on the rotating machine.

[0038] The electric telescopic structure includes a first servo motor 4, a right-angle reducer 19, a lead screw 17, a guide bar 9, and a connecting plate 10. The first servo motor 4 and the right-angle reducer 19 are connected together and respectively mounted on the support base. The output end of the right-angle reducer 19 is connected to the lead screw 17 hinged on the support base. The lead screw 17 extends vertically downward from the support base and the lower end is hinged to the connecting plate 10. The guide bar 9 is fixedly mounted on the connecting plate 10 and the support base. The load box 6 is nested on the lead screw 17 and the guide bar 9 and is threadedly connected to the lead screw 17. The microcontroller in the load box 6 is electrically connected to the first servo motor 4 to control the first servo motor 4. Thus, the control terminal held by the inspection personnel on site can control the first servo motor 4, the second servo motor 25, the electromagnet 13, and the vibration sensor 14, and receive the detection data from the vibration sensor 14 through interactive communication with the microcontroller in the load box 6.

[0039] Mechanism of Use: During inspection, the inspector remotely controls the drone to a high position on the large rotating machine that triggered the abnormal alarm. Using the drone's gimbal camera, the inspector determines the exact location and hovers the drone approximately 100mm above that position. Then, the inspector, holding a control terminal, controls the first servo motor 4 to rotate the lead screw 17. The load box 6 moves downwards along the lead screw 17, causing the end of the gimbal camera furthest from the camera to electrically extend downwards. The magnetic vibration sensor 14 extends downwards from the drone's landing gear 3 until the inspector observes through the gimbal camera that the magnetic vibration sensor 14 is about to touch the part of the rotating machine to be inspected. The inspector then remotely controls the load box... Six pairs of magnetic vibration sensors 14 are powered on, and the magnetic vibration sensors 14 are magnetically attached to the part to be tested on the rotating machine. At the same time, the second servo motor 25 in the load box 6 is controlled to drive the vertical connecting rod 11 to move upward, so that the lower end of the vertical connecting rod 11 is disengaged from the connecting sleeve 15 at the upper end of the magnetic vibration sensor 14. After the vibration sensor 14 is powered on, the inspection personnel hold a control terminal and judge in real time whether the abnormality is due to a problem with the pre-installed sensor or a fault in that part of the rotating machine, based on the data wirelessly transmitted by the controller in the load box 6 through the magnetic vibration sensor 14. The real-time diagnosis results are fed back to the operation center, which decides on the next steps.

[0040] Based on the above-mentioned real-time diagnostic device for large-scale rotating units in thermal power plants, the present invention also provides a real-time diagnostic method for large-scale rotating units in thermal power plants, comprising the following steps:

[0041] S1. The inspection personnel remotely control the drone to fly to the high part of the large rotating machine that generates an abnormal alarm at the inspection site, observe and determine the specific location through the drone's gimbal camera, and control the drone to hover above that location.

[0042] S2. The load box 6 extends downward from the end of the gimbal camera away from the camera. The magnetic vibration sensor 14 connected to the load box 6 via the vertical connecting rod 11 extends downward from the drone landing gear 3 until the inspection personnel observe through the gimbal camera that the magnetic vibration sensor 14 is about to touch the part of the rotating machine to be inspected.

[0043] S3. The inspection personnel remotely control the load box 6 pairs of magnetic vibration sensors 14 to power on, and the magnetic vibration sensors 14 are magnetically attracted to the part to be detected on the rotating machine and detached from the lower end of the vertical connecting rod 11.

[0044] S4. The inspection personnel use a handheld control terminal to determine in real time whether the abnormality is due to a problem with the pre-installed sensor or a fault in the corresponding part of the device, based on the data wirelessly transmitted by the controller in the load box 6 through the magnetic vibration sensor 14. The real-time diagnostic results are then fed back to the operation center, which decides on the next steps.

Claims

1. A method for real-time diagnosis of large rotating units in thermal power plants, characterized in that: Includes the following steps: S1. The inspection personnel remotely control the drone to fly to the high part of the large rotating machine that generates an abnormal alarm at the inspection site, observe and determine the specific location through the drone's gimbal camera, and control the drone to hover above that location. S2. A load cell extends downward from the end of the gimbal camera away from the camera, and a magnetic vibration sensor connected to the load cell via a vertical connecting rod extends downward from the drone landing gear. S3. The remote control load box powers on the magnetic vibration sensor, which magnetically attaches to the part to be detected on the rotating machine and detaches from the lower end of the vertical connecting rod. S4. The inspection personnel use a handheld control terminal to determine in real time whether the abnormality is due to a problem with the pre-installed sensor or a fault in the corresponding part of the device, based on the data wirelessly transmitted by the magnetic vibration sensor through the controller in the load box. The real-time diagnostic results are then fed back to the operation center, which decides on the next steps.

2. The real-time diagnostic method for large rotating units in a thermal power plant according to claim 1, characterized in that: One side of the magnetic vibration sensor is detachably snapped onto the lower end of the vertical connecting rod.

3. The real-time diagnostic method for large rotating units in a thermal power plant according to claim 2, characterized in that: The magnetic vibration sensor includes an electromagnet and a vibration sensor. The electromagnet is nested at the lower end of the vibration sensor, and the connecting wires of the electromagnet and the vibration sensor are electrically connected to the controller in the load box.

4. A real-time diagnostic device for large-scale rotating units in thermal power plants, characterized in that: The device includes a support base, an electrically telescopic structure, a load box, a vertical connecting rod, a spiral vibration isolation sleeve, a connecting sleeve, and a magnetic vibration sensor. The support base is mounted on the end of the drone gimbal camera away from the camera. The support base has a vertically downward-facing electrically telescopic structure, on which is a load box that can be moved up and down by the electrically telescopic structure. The lower end of the load box has a vertically downward-extending vertical connecting rod, and the lower end of the vertical connecting rod is detachably snapped with a connecting sleeve. A magnetic vibration sensor is locked onto the connecting sleeve. The end of the connecting wire of the magnetic vibration sensor near the load box is nested with a spiral vibration isolation sleeve to block the vibration transmitted between the load box and the magnetic vibration sensor through the connecting wire. The spiral vibration isolation sleeve is made of a rigid elastic material and extends downward in a spiral. The upper end of the spiral vibration isolation sleeve is fixedly mounted on the lower end surface of the load box.

5. The real-time diagnostic device for large-scale rotating units in thermal power plants according to claim 4, characterized in that: The magnetic vibration sensor includes an electromagnet and a vibration sensor. The electromagnet is nested at the lower end of the vibration sensor, and the connecting wires of the electromagnet and the vibration sensor are electrically connected to the controller in the load box.

6. The real-time diagnostic device for large-scale rotating units in thermal power plants according to claim 5, characterized in that: The load box contains a controller and a power supply. The power supply can power the controller, electromagnet and vibration sensor. The controller can wirelessly communicate with the control terminal of the on-site inspection personnel.

7. A real-time diagnostic device for large-scale rotating units in thermal power plants according to claim 6, characterized in that: The load box is also equipped with a second servo motor connected to the vertical connecting rod. The side of the second servo motor is abutted by a vertically extending limit rod used to restrict the planar movement of the second servo motor. A threaded sleeve that is helically nested on the upper end of the vertical connecting rod is fixedly provided on the lower end surface of the load box. The upper end of the vertical connecting rod is provided with an externally threaded section to form a threaded connection with the threaded sleeve.

8. The real-time diagnostic device for large-scale rotating units in thermal power plants according to claim 7, characterized in that: The lower outer wall of the vertical connecting rod is provided with an annular groove. The connecting sleeve is provided with a detachable sleeve for elastically nesting on the vertical connecting rod, so that the magnetic vibration sensor can be hung on the vertical connecting rod when it is not magnetically attached to the part to be detected on the rotating machine.

9. A real-time diagnostic device for large-scale rotating units in a thermal power plant according to claim 8, characterized in that: The electric telescopic structure includes a first servo motor, a right-angle reducer, a lead screw, a guide rod, and a connecting plate. The first servo motor and the right-angle reducer are connected together and respectively mounted on the support base. The output end of the right-angle reducer is connected to the lead screw hinged to the support base. The lead screw extends vertically downward from the support base and has a connecting plate hinged to its lower end. A guide rod is fixedly mounted on the connecting plate and the support base. The load box is nested on the lead screw and the guide rod and is threadedly connected to the lead screw.

10. A real-time diagnostic device for large-scale rotating units in a thermal power plant according to claim 9, characterized in that: With the load box moved downwards by the lead screw to the lower end of the lead screw, the upper end of the magnetic vibration sensor is lower than the lower end of the UAV's landing gear.

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