Hydrogenerator Unit Stability Detection and Calibration System and Method

Abstract

The stability detection and calibration system for a hydro-generating unit includes a sensor mounting bracket installed on the outer wall of the cover plate surrounding the main shaft of the hydro-generating unit. An eddy current sensor aligned with the axis of the main shaft of the hydro-generating unit is installed at the upper end of the sensor mounting bracket. The eddy current sensor is connected to a portable vibration and swing detector, and the portable vibration and swing detector is communicatively connected to a remote on-line monitoring system for the hydro-generating unit. It is applicable to monitoring and inspecting the operating status of specific components and parts concerned by users at any time on-site, and signal time-domain and frequency-spectrum analysis can be carried out. The device has a built-in sensor power supply, which avoids the cumbersome work of arranging sensor power supplies, power cables, etc. during on-site testing. Only by installing the sensors can data collection be carried out, reducing the on-site workload and providing a flexible and reliable testing device for on-site work. The vibration and swing data of relevant parts of the unit are detected by using the portable vibration and swing detector and compared with the monitoring data of the on-line monitoring system, so as to achieve the purpose of quickly locating and dealing with defects.

Description

Technical Field

[0001] The present invention relates to the technical field of hydroelectric power generation equipment, and particularly to a stability detection and correction system and method for a hydro-generator set. Background Art

[0002] On low-speed rotating machinery represented by hydro-generator sets, an on-line monitoring system is generally configured to monitor the operation conditions of key operating parts and components of the hydro-generator set, and to grasp the operation state of the unit in real time. When the unit is under maintenance or test, off-line test equipment is also used to test the unit.

[0003] The on-line monitoring system installs long-term effective monitoring points for key parts and components of the unit operation. Panels, signal acquisition, and analysis systems are arranged on site. The measuring points are comprehensive, fixedly installed, and operate for a long time. The disadvantage is that it is not easy to add new measuring points. If other components outside the already arranged measuring points need to be monitored, it is necessary to arrange for the generator set to stop for a long time or during the unit overhaul. At the same time, problems such as cable laying, installation of fixed sensor brackets, adaptation of the number of channels and acquisition frequency of the original monitoring system need to be considered, and the implementation difficulty is relatively large.

[0004] The stability data of the hydro-generator set operation is an important parameter indicating whether the unit operation state is excellent. The unit stability data is generally monitored in real time through the on-line monitoring system. When the stability data of the on-line monitoring system appears abnormal, it is extremely important to quickly and accurately find out the cause of the abnormality. However, its failure causes are diverse, which may be sensor failures, equipment itself vibration and swing, or cable and transmission equipment line failures. It often takes a huge amount of time to find out the specific cause of the failure and requires the unit to stop, resulting in great economic losses. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a stability detection and correction system and method for a hydro-generator set, which can help technicians quickly analyze the cause of abnormal vibration and swing data, accurately locate the fault point, and judge whether it is the abnormal vibration and swing of the equipment itself or the defects of the vibration and swing sensor and the on-line monitoring system, so as to achieve the purpose of timely handling defects and avoiding the expansion of defects.

[0006] To solve the above technical problem, the technical solution adopted by the present invention is:

[0007] A stability detection and correction system for a hydro-generator set includes a sensor mounting bracket installed on the outer wall of the cover plate around the main shaft of the hydro-unit. An eddy current sensor aligned with the axis of the main shaft of the hydro-unit is installed at the upper end of the sensor mounting bracket. The eddy current sensor is connected to a portable vibration and swing detector, and the portable vibration and swing detector is communicatively connected to a remote on-line monitoring system of the hydro-generator set.

[0008] The above-mentioned portable vibration and swing detector has two communication connection methods, wired and wireless, with the remote on-line monitoring system of the water turbine unit.

[0009] The above-mentioned portable vibration and swing detector includes a vibration and swing detector housing. Inside the housing, there is a signal conditioning module, which is connected to the sensor interface on the housing. There are multiple sensor interfaces, which are connected to the multi-channel signal interfaces of the signal conditioning module. The output end of the signal conditioning module is electrically connected to the input end of the AD conversion module. The output end of the AD conversion module is electrically connected to the main board and the storage module. The main board and the storage module are provided with a USB interface for wired data transmission. The main board and the storage module are connected to the liquid crystal display through the display driver. The main board and the storage module are connected to the wireless transmission module.

[0010] The above-mentioned sensor mounting bracket includes a "Z"-shaped bracket in a lateral "Z" shape. The inner sides of the two lower ends of the "Z"-shaped bracket are respectively attached to the upper wall and the side wall of the cover plate. One upward end of the "Z"-shaped bracket is provided with a sensor mounting hole. One downward end of the "Z"-shaped bracket is provided with an outward protruding handle mounting stud for mounting a handle. One end of the handle is provided with a concave hole corresponding to the size of the handle mounting stud.

[0011] There are multiple above-mentioned sensor mounting brackets. The shapes of the inner sides of the two lower ends respectively correspond to the side wall arc surface and the upper plane of the cover plate at the positions of the upper guide bearing, the lower guide bearing and the water guide bearing. The axis of the sensor mounting hole is aligned with the axis of the side wall arc surface.

[0012] The above-mentioned portable vibration and swing detector is provided with a battery, which is connected to the power conversion module. The power conversion module supplies power to each module inside the portable vibration and swing detector.

[0013] For the detection method using the above-mentioned stability detection and calibration system of the water turbine generator set, the detection steps are as follows:

[0014] Step 1: Install the sensor mounting bracket on the corresponding cover plate at the position of the water turbine unit to be detected and calibrated. Install the eddy current sensor in the sensor mounting hole and adjust it to the detection position. Connect the eddy current sensor to the portable vibration and swing detector. Use the handle to make the sensor mounting bracket closely attached to the cover plate. Magnetically adsorb the vibration sensor on the main shaft of the water turbine unit and connect it to the portable vibration and swing detector for detection to obtain the vibration and swing values at this position of the unit, which are defined as measured value A.

[0015] Step 2: Compare the measured value B in the on-line monitoring system of the water turbine unit with the measured value A. If the measured values of A and B are the same, the detection value of the on-line monitoring system of the water turbine unit is accurate. If the measured values of A and B are different, the detection value of the on-line monitoring system of the water turbine unit is distorted, and enter Step 3.

[0016] Step 3: Connect the eddy current sensor connected to the front end of the hydro-generator unit online monitoring system to a portable vibration and swing detector for measurement to obtain a measured value C;

[0017] Step 4: If the measured value C is consistent with the measured value B, the eddy current sensor at the front end is faulty and needs to be replaced. If they are inconsistent, proceed to Step 5;

[0018] Step 5: If the measured value C is consistent with the measured value A, the eddy current sensor at the front end is normal. It should be the fault of the channel and system after this front-end eddy current sensor. At this time, connect the eddy current sensor on the sensor mounting bracket that is connected to the portable vibration and swing detector to the hydro-generator unit online monitoring system. The online monitoring system obtains a measured value D. If the measured value D is consistent with the measured value B, confirm the fault of the channel and system after the front-end eddy current sensor.

[0019] The stability detection and correction system and method for a hydro-generator unit provided by the present invention utilize a portable vibration and swing detector to detect the vibration and swing data of relevant parts of the unit, and compare them with the monitoring data of the online monitoring system, so as to achieve the purpose of quickly locating and handling defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below with reference to the drawings and embodiments:

[0021] Figure 1 is the schematic diagram of the principle of the portable vibration and swing detector;

[0022] Figure 2 is the structural schematic diagram of the portable detector;

[0023] Figure 3 is the connection schematic diagram of the stability detection and correction system for the hydro-generator unit;

[0024] Figure 4 is the structural schematic of the sensor mounting bracket Figure 1 ;

[0025] Figure 5 is the structural schematic of the sensor mounting bracket Figure 2 ;

[0026] Figure 6 is the structural schematic diagram of the handle;

[0027] Figure 7 is the electrical schematic diagram of the portable vibration and swing detector;

[0028] Figure 8 is the signal conditioning circuit schematic diagram of the signal conditioning module;

[0029] Figure 9 is the circuit connection diagram of the AD conversion module;

[0030] Figure 10 This is the circuit connection diagram of the wireless transmission module.

[0031] Among them: power conversion module 1, battery 2, signal conditioning module 3, AD conversion module 4, main board and storage module 5, vibration pendulum instrument housing 6, sensor interface 7, USB interface 8, main shaft of the water turbine unit 9, sensor mounting bracket 10, "Z"-shaped bracket 101, sensor mounting hole 102, handle mounting stud 103, eddy current sensor 11, handle 12, concave hole 121, cover plate 13, display driver 14, wireless transmission module 15. Specific implementation mode

[0032] As Figure 3 shown in , the stability detection and correction system of the water turbine generator set includes a sensor mounting bracket 10 installed on the outer wall of the cover plate 13 surrounding the main shaft 9 of the water turbine generator set. An eddy current sensor 11 aligned with the axis of the main shaft 9 of the water turbine generator set is installed at the upper end of the sensor mounting bracket 10. The eddy current sensor 11 is connected to a portable vibration pendulum detector, and the portable vibration pendulum detector is communicatively connected to a remote on-line monitoring system of the water turbine generator set.

[0033] There are two communication connection methods, wired and wireless, between the above-mentioned portable vibration pendulum detector and the remote on-line monitoring system of the water turbine generator set.

[0034] By installing the sensor mounting bracket 10 on the cover plate 13 at various positions of the water turbine main shaft, aligning the eddy current sensor 11 with the axis of the main shaft 9 of the water turbine generator set and performing on-site monitoring of the vibration pendulum of the main shaft of the water turbine generator set through a portable vibration pendulum detector, the on-site detection result of the vibration pendulum degree of the main shaft of the water turbine generator set can be obtained. The portable vibration pendulum detector has been calibrated through experiments before use, and its on-site detection result is the real vibration pendulum degree of the main shaft on-site. By comparing the on-site vibration pendulum detection result with the on-line monitoring result in the remote on-line monitoring system of the water turbine generator set, and by disassembling the on-line monitored eddy current sensor and installing it on the sensor mounting bracket 10, and by switching the wired and wireless communication methods between the portable vibration pendulum detector and the remote on-line monitoring system of the water turbine generator set, the accuracy and distortion reasons of the vibration pendulum data of the on-line monitoring system of the water turbine generator set can be obtained, and calibration can be performed by using the real on-site vibration pendulum detection data.

[0035] As Figure 1 、 2As shown in FIGS. 7-10, the above-mentioned portable vibration and swing detector includes a vibration and swing detector housing 6. Inside the vibration and swing detector housing 6, there is a signal conditioning module 3. The signal conditioning module 3 is connected to a sensor interface 7 on the vibration and swing detector housing 6. There are multiple sensor interfaces 7, which are connected to the multi-channel signal interface of the signal conditioning module 3. The output end of the signal conditioning module 3 is electrically connected to the input end of the AD conversion module 4. The output end of the AD conversion module 4 is electrically connected to the main board and storage module 5. A USB interface 8 is provided on the main board and storage module 5 for wired data transmission. The main board and storage module 5 are connected to a liquid crystal display through a display driver 14. The main board and storage module 5 are connected to a wireless transmission module 15.

[0036] The signal of the main shaft 9 of the water turbine unit detected by the eddy current sensor 11 enters the signal conditioning module 3. Since the signal conditioning module 3 has a multi-channel signal interface, vibration and swing detection can be carried out at multiple positions simultaneously through multiple sensor mounting brackets 10. For example, vibration and swing detection can be carried out simultaneously at the upper guide bearing, lower guide bearing, and water guide bearing. The main function of the signal conditioning module 3 is to amplify and filter various sensor signals and condition them to the range that can be recognized by the AD conversion chip. The general range is ±5V, and the output range of the sensors used in the equipment design is ±8V. Therefore, the sensor signals need to be amplified by 1 / 2 first.

[0037] In engineering measurement, the sampling frequency cannot be infinitely high and does not need to be infinitely high because generally only the signal components within a certain frequency range are concerned. A low-pass filter is needed to filter out the frequency components higher than 1 / 2 of the sampling frequency, that is, anti-aliasing filtering. In dynamic signal testing, the measuring instrument must have anti-aliasing filtering function. If the analog signal of vibration is not subjected to low-pass anti-aliasing filtering, the high-order modal frequencies are likely to be aliased into the low-frequency band, forming false modal frequencies, which brings difficulties to the identification of modal parameters. According to the signal characteristics of the water turbine generator unit, the equipment adopts a 1kHz 6th-order anti-aliasing filtering design. The AD conversion adopts a 4-channel 16-bit synchronous acquisition mode, and the highest acquisition rate of the channel is 200ksps.

[0038] As Figures 4 - 6 shown in FIG., the above-mentioned sensor mounting bracket 10 includes a "Z" - shaped bracket 101 in a lateral "Z" shape. The inner sides of the two lower ends of the "Z" - shaped bracket 101 are respectively attached to the upper wall and the side wall of the cover plate 13. The upper end of the "Z" - shaped bracket 101 is provided with a sensor mounting hole 102. The lower end of the "Z" - shaped bracket 101 is provided with an outward - protruding handle mounting stud 103 for mounting a handle 12. One end of the handle 12 is provided with a concave hole 121 corresponding to the size of the handle mounting stud 103.

[0039] When applying force to the handle mounting stud 103 through the hand-held handle 12, press the inner two sides on one side of the lower end of the "Z"-shaped bracket 101 tightly against the upper wall and the side wall of the cover plate 13, align the eddy current sensor 11 with the axis of the main shaft 9 of the water turbine unit, and the standard position adjustment of the vibration and swing detection of the main shaft can be achieved by adjusting the radial position of the eddy current sensor 11.

[0040] There are multiple sensor mounting brackets 10 as described above. The shapes of the inner two sides at the lower end respectively correspond to the side wall arc surface and the upper plane of the cover plate 13 at the positions of the upper guide bearing, the lower guide bearing, and the water guide bearing, and the axis of the sensor mounting hole 102 is aligned with the axis of the side wall arc surface.

[0041] Through the setting of the shapes of the inner two sides of the sensor mounting bracket 10 and the cooperation with the axis position of the sensor mounting hole 102, the eddy current sensor 11 is automatically aligned with the axis of the main shaft of the water turbine unit during installation.

[0042] The eddy current sensor used for swing measurement mainly monitors the main shaft. The sensor bracket is generally installed on the oil sump cover plate. The oil sump body is made of rigid material, but the materials of the oil sump cover plate are different, including rigid and aluminum ones, and the aluminum cover plate accounts for a large proportion. The magnetic base cannot meet all requirements in swing measurement. Therefore, it is necessary to optimize the design of the bracket, and the above-mentioned arc surface corresponding design can be used to rotate and align the axis.

[0043] As Figure 1 As shown in the figure, a battery 2 is provided inside the above-mentioned portable vibration and swing detector. The battery 2 is connected to the power conversion module 1, and the power conversion module 1 supplies power to each module inside the portable vibration and swing detector.

[0044] Using the detection method of the above-mentioned water turbine generator unit stability detection and correction system, the detection steps are as follows:

[0045] Step 1: Install the sensor mounting bracket 10 on the corresponding cover plate at the position of the water turbine unit to be detected and calibrated. Install the eddy current sensor 11 in the sensor mounting hole 102 and adjust it to the detection position. Connect the eddy current sensor 11 to the portable vibration and swing detector. Use the handle 12 to make the sensor mounting bracket 10 close to the cover plate 13. Magnetically adsorb the vibration sensor on the main shaft 9 of the water turbine unit and connect it to the portable vibration and swing detector for detection to obtain the vibration and swing values at this position of the unit, which are defined as measured value A;

[0046] Step 2: Compare the measured value B in the on-line monitoring system of the water turbine unit with the measured value A. If the measured values of A and B are the same, the detection value of the on-line monitoring system of the water turbine unit is accurate. If the measured values of A and B are different, the detection value of the on-line monitoring system of the water turbine unit is distorted, and enter Step 3;

[0047] Step 3: Connect the eddy current sensor connected to the front end of the on-line monitoring system of the water turbine unit to a portable vibration and swing detector for measurement to obtain a measured value C;

[0048] Step 4: If the measured value C is consistent with the measured value B, the eddy current sensor at the front end is faulty and needs to be replaced. If they are inconsistent, proceed to Step 5;

[0049] Step 5: If the measured value C is consistent with the measured value A, the eddy current sensor at the front end is normal. It should be the fault of the channel and system after this front-end eddy current sensor. At this time, connect the eddy current sensor 11 connected to the portable vibration and swing detector on the sensor mounting bracket 10 to the on-line monitoring system of the water turbine unit. The on-line monitoring system obtains a measured value D. If the measured value D is consistent with the measured value B, confirm the fault of the channel and system after the front-end eddy current sensor.

Claims

1. A method for detecting and correcting the stability of a hydro-generating unit, characterized in that, It includes a sensor mounting bracket (10) installed on the outer wall of a cover plate (13) surrounding the main shaft (9) of a water turbine unit. An eddy current sensor (11) aligned with the axis of the main shaft (9) of the water turbine unit is installed at the upper end of the sensor mounting bracket (10). The eddy current sensor (11) is connected to a portable vibration and swing detector, and the portable vibration and swing detector is communicatively connected to a remote on-line monitoring system of the water turbine unit; The said sensor mounting bracket (10) includes a "Z"-shaped bracket (101) in a lateral "Z" shape. The inner sides of the two faces at the lower end of the "Z"-shaped bracket (101) are respectively attached to the upper wall and the side wall of the cover plate (13). A sensor mounting hole (102) is provided at the upward end of the "Z"-shaped bracket (101), and a handle mounting stud (103) protruding outward is provided at the downward end of the "Z"-shaped bracket (101) for mounting a handle (12). A concave hole (121) corresponding to the size of the handle mounting stud (103) is provided at one end of the handle (12); The steps of detection are as follows: Step 1: Install the sensor mounting bracket (10) on the corresponding cover plate at the position of the water turbine unit to be detected and calibrated. Install the eddy current sensor (11) in the sensor mounting hole (102) and adjust it to the detection position. Connect the eddy current sensor (11) to the portable vibration and swing detector. Use the handle (12) to make the sensor mounting bracket (10) closely adhere to the cover plate (13). Magnetically adsorb the vibration sensor on the main shaft (9) of the water turbine unit and connect it to the portable vibration and swing detector for detection to obtain the vibration and swing values at this position of the unit, which are defined as measured value A; Step 2: Compare the measured value B in the on-line monitoring system of the water turbine unit with the measured value A. If the measured values of A and B are consistent, the detection value of the on-line monitoring system of the water turbine unit is accurate. If the measured values of A and B are inconsistent, the detection value of the on-line monitoring system of the water turbine unit is distorted, and proceed to Step 3; Step 3: Connect the eddy current sensor connected to the front end of the on-line monitoring system of the water turbine unit to the portable vibration and swing detector for measurement to obtain the measured value C; Step 4: If the measured value C is consistent with the measured value B, the eddy current sensor at the front end is faulty and needs to be replaced. If they are inconsistent, proceed to Step 5; Step 5: If the measured value C is consistent with the measured value A, the eddy current sensor at the front end is normal. It should be the fault of the channel and the system after this front-end eddy current sensor. At this time, connect the eddy current sensor (11) connected to the portable vibration and swing detector on the sensor mounting bracket (10) to the on-line monitoring system of the water turbine unit. The on-line monitoring system obtains the measured value D. If the measured value D is consistent with the measured value B, confirm the fault of the channel and the system after the front-end eddy current sensor.

2. The stability detection and correction method for a hydro-generating unit according to claim 1, characterized in that The said portable vibration and swing detector and the remote on-line monitoring system of the water turbine unit have two communication connection methods: wired and wireless.

3. The stability detection and correction method for a hydro-generating unit according to claim 2, characterized in that, The described portable vibration and swing detector includes a vibration and swing detector housing (6). Inside the vibration and swing detector housing (6), there is a signal conditioning module (3). The signal conditioning module (3) is connected to a sensor interface (7) on the vibration and swing detector housing (6). There are multiple sensor interfaces (7) which are connected to the multi-channel signal interface of the signal conditioning module (3). The output end of the signal conditioning module (3) is electrically connected to the input end of the AD conversion module (4). The output end of the AD conversion module (4) is electrically connected to the main board and storage module (5). The main board and storage module (5) are provided with a USB interface (8) for wired data transmission. The main board and storage module (5) are connected to a liquid crystal display through a display driver (14). The main board and storage module (5) are connected to a wireless transmission module (15).

4. The stability detection and correction method of the water turbine generator set according to claim 3, characterized in that, There are multiple described sensor mounting brackets (10). The inner sides of the lower ends of the sensor mounting brackets (10) respectively correspond to the side wall arc surface and the upper plane of the cover plate (13) at the positions of the three bearings, namely the upper guide bearing, the lower guide bearing and the water guide bearing. The axis of the sensor mounting hole (102) is aligned with the axis of the side wall arc surface.

5. The stability detection and correction method of the hydro-generating unit according to claim 3, characterized in that, The described portable vibration and swing detector is provided with a battery (2). The battery (2) is connected to a power conversion module (1). The power conversion module (1) supplies power to each module inside the portable vibration and swing detector.

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