Method for measuring air gap of hydraulic generator

Abstract

According to the hydro-generator air gap measuring method, the electric telescopic rod is combined with the intelligent trolley, different parameters are set for the intelligent trolley according to different field conditions, and the hydro-generator air gap measuring method can be suitable for various measuring environments; the shaking degree during measurement can be reduced by using extension and contraction of the electric telescopic measuring rod, and meanwhile, result errors caused by operation errors are reduced by combining a data analysis algorithm and direct data display; the electric telescopic measuring rod is quickly extended and shortened by adopting the matching linkage of a fixed pulley block and a fixed block, and the stroke of the telescopic rod is enhanced; meanwhile, the electromagnet is electrified to generate magnetism, so that the device can be adsorbed and fixed on the surface of the stator during operation, the stability of the device is enhanced, the operation can be further remotely controlled through the Bluetooth module, the air gap measurement operation is simpler and more convenient, the air gap measurement precision and measurement efficiency are greatly improved, and the practicability is high. And lots of manpower and material resources are saved.

Description

Technical Field

[0001] The present invention belongs to the field of measuring the air gap between the stator and rotor of a hydrogenerator, and particularly relates to a method for measuring the air gap of a hydrogenerator. Background Art

[0002] In a hydrogenerator set, the air gap between the stator and rotor is very important. The size of the air gap directly affects the magnetic field strength and magnetic resistance between the stator and rotor. A smaller air gap can improve the efficiency of the motor because the magnetic field is stronger and the magnetic resistance is smaller. At the same time, the air gap is also affected by mechanical and thermal expansion. During operation, mechanical vibration or temperature change may cause a slight change in the size of the air gap, which may affect the performance and service life of the equipment. Every time the unit undergoes a major overhaul, before lifting out the rotor, the air gap between the stator and rotor should be measured and recorded to check whether it meets the specified value.

[0003] Most traditional air gap measuring tools utilize the relationship between the movement and inclination of two opposing wedges, and measure the value of the air gap through the change in their relative height, and obtain the reading according to the scale on the main shaft. However, during manual operation, due to the friction of the wedge blocks, the excessive length and thinness of the main shaft, which is prone to distortion, etc., the error increases. Moreover, the generally used main shaft is in an elongated shape and is easily damaged during transportation, such as bending, bumping, breaking, etc. When in use, the left - right swing is also likely to make the main shaft not perpendicular to the wedge block, resulting in a deviation between the measured result and the actual value. Traditional measuring tools generally use a scale, and errors are easily generated when manually measuring and operating. For example, reading errors may occur when observing data, and in some cases, the accuracy of the scale is not high, and the change in the air gap value cannot be accurately detected. Summary of the Invention

[0004] The object of the present invention is to propose a method for measuring the air gap of a hydrogenerator, which is used to solve the technical problems that the measurement result of the air gap of the hydrogenerator rotor is inaccurate, the requirements for workers' operations are relatively high, which greatly wastes human and material resources, and prolongs the installation and maintenance time of the hydrogenerator set.

[0005] To achieve the above object, the present invention provides the following technical solution: A method for measuring the air gap of a hydrogenerator, which uses an air gap measuring device for measurement. The air gap measuring device includes an intelligent trolley, an electric telescopic measuring rod, an adsorption component, and a battery pack;

[0006] The front end of the intelligent vehicle is provided with sensors, including an infrared line-tracking sensor and an ultrasonic ranging sensor. The sensors are connected to a single-chip microcomputer inside the intelligent vehicle. There is a motor drive module on each side of the single-chip microcomputer to connect to the tires of the vehicle, for realizing the transmission control of the forward, backward, turning and stopping of the intelligent vehicle through the sensor signal - single-chip microcomputer - motor drive module; the single-chip microcomputer transmits the measurement data through a wireless transmission module and displays it in the computer system;

[0007] The electric telescopic measuring rod is installed on one side of the intelligent vehicle. The electric telescopic measuring rod includes a housing, a motor, a lead screw, telescopic section a, telescopic section b, telescopic section c and an extension plate: the extension plate is welded to the left side of the housing, the extension plate is fixedly connected to the intelligent vehicle by screws, a support column is fixedly connected below the extension plate by screws, and the lower end of the support column is welded to the intelligent vehicle; the lead screw is connected to the telescopic section a through a threaded through hole at the top of the telescopic section a, and there is a thread on the lead screw that mates with the thread of the through hole. The motor drives the lead screw to rotate, thereby driving the relative telescopic movement between the telescopic section a and the housing. The relative telescopic movement between the telescopic section a and the telescopic section b and between the telescopic section b and the telescopic section c is realized through the cooperation of a connecting rope, a fixed pulley and a fixed block; a left air-gap sensor and a right air-gap sensor are respectively arranged on the left and right sides of the telescopic section c, for measuring the distance between the telescopic section c and the inner surface of the stator and the rotor magnetic pole;

[0008] The adsorption component includes an electromagnet, a spring base, a reset plate and a reset spring. The electromagnet is installed on the other side of the intelligent vehicle. The spring base is fixed on the intelligent vehicle by screws. A cylindrical central shaft is sandwiched between the two spring bases. The diameter of the central shaft is the same as the inner diameter of the spring base. The reset spring is sleeved on the central shaft. The reset plate includes an upper pressure plate and a support plate arranged at an acute angle and a fixing hole for sleeving on the central shaft. The center line of the fixing hole coincides with the axis of the central shaft. The reset spring includes a main body portion sleeved on the central shaft and two elastic feet at an angle. The elastic feet are respectively in contact with the flat plate of the spring base and the upper pressure plate of the reset plate. The lower end of the reset plate is fixedly connected to the electromagnet by screws;

[0009] The battery pack includes a voltage stabilization module for supplying power to electric components;

[0010] When using the air-gap measuring device for measurement, it specifically includes the following steps:

[0011] S1. Place the intelligent vehicle on the stator surface so that the electric telescopic measuring rod can just reach into the air gap between the stator and the rotor. According to the position of the intelligent vehicle, stick black tape on the stator surface. The black tape faces the center of the vehicle. Under the action of the infrared line-tracking sensor, the intelligent vehicle travels along the route. If it encounters an obstacle, the intelligent vehicle stops under the action of the ultrasonic ranging sensor. When the intelligent vehicle travels to the center of the rotor pole, the intelligent vehicle stops. Power on the adsorption component, and the electromagnet of the adsorption component adsorbs on the stator surface to make the intelligent vehicle stable and immobile. Then start the electric telescopic measuring rod and let the electric telescopic measuring rod reach a certain length to start measuring.

[0012] S2. To avoid measurement errors caused by the jitter of the electric measuring telescopic rod, after it extends to an appropriate length, wait for 3 - 5 s. Wait until the readings are stable and then record the data. After the measurement is completed, control the motor of the electric telescopic measuring rod to reverse, retract the electric telescopic measuring rod, then power off the adsorption component, and then start the vehicle to go to the next measurement point and repeat the measurement steps.

[0013] S2. Divide the measurement range of the electric telescopic measuring rod into ten equal parts according to its extended length, and denote them as h1, h2, h3, h4, h5, h6, h7, h8, h9, h 10 , unit: mm;

[0014] S3. Denote the distance measured by the left air gap sensor from the current position to the rotor pole as l a , and denote the distance measured by the right air gap sensor from the current position to the inner surface of the stator as l b . When it is within the height range of h2, denote the distance measured by the left air gap sensor from the current position to the rotor pole as l h2a , and denote the distance measured by the right air gap sensor from the current position to the inner surface of the stator as l h2b , and so on for the distance records at other heights;

[0015] S. Directly transmit the measured data to the display screen and process it to obtain the maximum value la a of the distance l max measured by the left air gap sensor from the current position to the rotor pole, the minimum value la min , the average value la avg , and the variance δ a

[0016]

[0017] The difference between the maximum value and the minimum value is:

[0018] la R = la max - la min The unit is mm;

[0019] The distance l measured at the current position of the right air gap sensor from the inner surface of the stator b The maximum value lb max The minimum value lb min The average value lb avg The variance δ b

[0020]

[0021] The difference between the maximum value and the minimum value is:

[0022] lb R = lb max - lb min

[0023]

[0024] Analyze the test values. If the value of the variance or the range exceeds 0.05, it is initially concluded that there is a deviation in the stator or the rotor poles of the water turbine; The total thickness of the left air gap sensor, the right air gap sensor, and the expansion joint c is denoted as l = 11 mm. At different heights, add the distance measured at the current position of the left air gap sensor from the rotor poles, the distance measured at the current position of the right air gap sensor from the inner surface of the stator, and the thicknesses of the two air gap sensors and the expansion joint c. That is, within the height range h1, the air gap value is calculated according to the following formula: L1 = l h1a + l h1b + l (the unit is mm). The calculation methods for other height ranges are the same as those within the height range h1;

[0025] S5. Compare the length L1 with the standard value of the water turbine air gap to determine whether it exceeds 5% of the air gap design value. If it exceeds, an alarm is issued.

[0026] Preferably, it further includes a Bluetooth module, and the Bluetooth module is used for the control of the intelligent trolley by a mobile communication device.

[0027] Preferably, the cooperation between the connecting rope, the fixed pulley and the fixed block is specifically as follows: on the upper and lower ends of the left and right side walls of the telescopic joint a, there are respectively an upper left pulley a, a lower left pulley a, an upper right pulley a and a lower right pulley a. The left connecting rope a forms a closed loop to link the upper left pulley a and the lower left pulley a. The left section of the left connecting rope a is fixedly connected to the first left fixed block, and the first left fixed block is arranged at the near lower end inside the housing. The right section of the left connecting rope a is fixedly connected to the second left fixed block, and the second left fixed block is arranged at the near upper end outside the telescopic joint b. The cooperation mode of the upper right pulley a, the lower right pulley a, the right connecting rope a, the first right fixed block and the second right fixed block is the same as that of the upper left pulley a, the lower left pulley a, the left connecting rope a, the first left fixed block and the second left fixed block. On the upper and lower ends of the left and right side walls of the telescopic joint b, there are respectively an upper left pulley b, a lower left pulley b, an upper right pulley b and a lower right pulley b. The left connecting rope b forms a closed loop to link the upper left pulley b and the lower left pulley b. The left section of the left connecting rope b is fixedly connected to the third left fixed block, and the third left fixed block is arranged at the near lower end inside the telescopic joint a. The right section of the left connecting rope b is connected to the fourth left fixed block, and the fourth left fixed block is arranged at the near upper end outside the telescopic joint c. The cooperation mode of the upper right pulley a, the lower right pulley a, the right connecting rope a, the third right fixed block and the fourth right fixed block is the same as that of the upper left pulley a, the lower left pulley a, the left connecting rope a, the third left fixed block and the fourth left fixed block. When the electric telescopic measuring rod needs to be extended, the motor is powered by V voltage. The motor is started to make the lead screw rotate clockwise. The thread on the lead screw is matched with the thread of the through hole, driving the telescopic joint a to extend. Under the cooperation of the fixed pulley and the fixed block, the telescopic joint b extends relative to the telescopic joint a. The third fixed block arranged on the telescopic joint a moves upward relative to the telescopic joint b, thereby driving the fourth fixed block arranged on the telescopic joint c to move downward and extend, realizing the extension of the electric telescopic measuring rod. When the electric telescopic measuring rod needs to be shortened, the motor is powered by V voltage. The motor is started to make the lead screw rotate counterclockwise, realizing the shortening of the electric telescopic measuring rod.

[0028] Preferably, the fixed pulley is installed on the side wall of the telescopic joint through a fixed shaft arranged on the telescopic joint, and the linkage plane of the fixed pulley and the connecting rope is perpendicular to the side wall of the telescopic joint.

[0029] Preferably, anti-collision rubber pads are arranged on the telescopic joint c and the housing.

[0030] Preferably, the thickness of the anti-collision rubber pad is 4.5 mm.

[0031] Preferably, the infrared tracking sensor and the ultrasonic ranging sensor are used for detection. According to the actual situation on site, when the intelligent vehicle deviates from the predetermined travel track by 5 cm or is 5 cm away from an obstacle, it will automatically stop and alarm on the operation interface, without the need for manual intervention, improving the measurement efficiency.

[0032] The present invention has the following beneficial effects compared with the prior art:

[0033] A method for measuring the air gap of a hydrogenerator proposed by the present invention combines an electric telescopic rod with an intelligent vehicle. The intelligent vehicle can realize automatic driving for measurement. Only different parameters need to be set for the vehicle according to different on-site situations, and it can be applied to a variety of measurement environments. Using a motor to control the extension and contraction of the electric telescopic measuring rod can reduce the shaking degree during measurement. At the same time, combined with a data analysis algorithm, the data is directly displayed, reducing the result error caused by operation errors. The electric telescopic measuring rod uses a fixed pulley group and a fixed block to cooperate and link to achieve rapid extension and shortening, and enhances the stroke of the telescopic rod. At the same time, using an electromagnet to generate magnetism when energized enables the device to be adsorbed and fixed on the stator surface during operation, enhancing the stability of the device. The above operations can be further remotely controlled through a Bluetooth module, making the air gap measurement operation simpler and more convenient. The use of the electromagnet can make the device fit more closely and will not cause damage to the water turbine, greatly improving the accuracy and measurement efficiency of the air gap measurement, saving a large amount of manpower and material resources, and solving the technical problems in the traditional measurement method that the measurement result of the air gap of the hydrogenerator rotor is inaccurate, and at the same time, it has high requirements for the operation of workers, greatly wasting manpower and material resources, and prolonging the installation and maintenance time of the hydrogenerator unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is the work flow of the method for measuring the air gap of the hydrogenerator of the present invention;

[0035] Figure 2 is a schematic diagram of the air gap measurement device adopted by the method for measuring the air gap of the hydrogenerator of the present invention;

[0036] Figure 3 is a schematic diagram of the electric telescopic measuring rod of the air gap measurement device adopted by the method for measuring the air gap of the hydrogenerator of the present invention;

[0037] Figure 4 is a schematic diagram of the adsorption component of the air gap measurement device adopted by the method for measuring the air gap of the hydrogenerator of the present invention;

[0038] Figure 5 is a measurement schematic diagram of the method for measuring the air gap of the hydrogenerator of the present invention.

[0039] Reference numerals: 1 - intelligent vehicle; 11 - infrared line - tracking sensor; 12 - ultrasonic ranging sensor; 2 - electric telescopic measuring rod; 21 - housing; 211 - first left fixing block; 22 - telescopic section a; 221 - third left fixing block; 23 - telescopic section b; 231 - second left fixing block; 24 - telescopic section c; 241 - fourth left fixing block; 242 - air - gap sensor; 243 - anti - collision rubber pad; 25 - left connecting rope a; 251 - upper left pulley a; 252 - lower left pulley a; 26 - left connecting rope b; 261 - upper left pulley b; 262 - lower left pulley b; 27 - motor; 28 - lead screw; 3 - support column; 4 - extension plate; 5 - adsorption component; 51 - spring base; 52 - reset plate; 53 - electromagnet; 54 - reset spring. Detailed implementation mode

[0040] To enable those skilled in the art to better understand the measurement method of the present invention, the present invention will be further described in detail below with specific embodiments in conjunction with the accompanying drawings. However, it is not limited to a specific example only, and this method can be applied to similar situations.

[0041] Embodiment 1

[0042] Please refer to Figures 2 to 5 , a measuring device for the air gap of a hydro - generator, comprising: an intelligent vehicle 1, an electric telescopic measuring rod 2, an adsorption component 5, a battery pack and a Bluetooth module. The Bluetooth module is used for controlling the intelligent vehicle 1 by a mobile communication device;

[0043] The front end of the intelligent vehicle 1 is provided with sensors, and the sensors include an infrared line - tracking sensor 112 and an ultrasonic ranging sensor 12. The sensors are connected to a single - chip microcomputer inside the intelligent vehicle 1. On both sides of the single - chip microcomputer, there is a motor 27 driving module connected to the tires of the vehicle, which is used to realize the transmission control of the intelligent vehicle 1 for forward, backward, turning and stopping through the sensor signal - single - chip microcomputer - motor driving module; the single - chip microcomputer transmits the measurement data to a computer system through a wireless transmission module and displays it.

[0044] The electric telescopic measuring rod 2 is installed on one side of the intelligent vehicle 1. The electric telescopic measuring rod 2 includes a housing 21, a motor 27, a lead screw 28, a telescopic section a 22, a telescopic section b 23, a telescopic section c 24 and an extension plate 4: The extension plate 4 is welded to the left side of the housing 21. The extension plate 4 is fixedly connected to the intelligent vehicle 1 by screws. A support column 3 is fixedly connected to the lower part of the extension plate 4 by screws. The lower end of the support column 3 is welded to the intelligent vehicle 1. The lead screw 28 is connected to the telescopic section a 22 through a threaded through hole at the top of the telescopic section a 22. There is a thread on the lead screw 28 that is in threaded cooperation with the thread of the through hole. The motor 27 drives the rotation of the lead screw 28 to drive the relative telescopic movement between the telescopic section a 22 and the housing 21. The relative telescopic movement between the telescopic section a 22 and the telescopic section b 23 and between the telescopic section b 23 and the telescopic section c 24 is realized through the cooperation between a connecting rope, a fixed pulley and a fixed block to achieve the relative telescopic movement between two adjacent telescopic sections.

[0045] Please refer to Figure 2, the fixed pulley is installed on the side wall of the telescopic section through a fixed shaft provided on the telescopic section, and the linkage plane of the fixed pulley and the connecting rope is perpendicular to the side wall of the telescopic section.The cooperation between the connecting rope, the fixed pulley and the fixed block is specifically as follows: on the upper and lower ends of the left and right side walls of the telescopic joint a22, there are respectively an upper left pulley a251, a lower left pulley a252, an upper right pulley a and a lower right pulley a. The left connecting rope a25 is a closed loop that links the upper left pulley a251 and the lower left pulley a252. The left section of the left connecting rope a25 is fixedly connected to the first left fixed block 211, and the first left fixed block 211 is arranged near the lower end inside the housing 21. The right section of the left connecting rope a25 is fixedly connected to the second left fixed block 231, and the second left fixed block 231 is arranged near the upper end outside the telescopic joint b23. The cooperation mode of the upper right pulley a, the lower right pulley a, the right connecting rope a, the first right fixed block and the second right fixed block is the same as that of the upper left pulley a251, the lower left pulley a252, the left connecting rope a25, the first left fixed block 211 and the second left fixed block 231. On the upper and lower ends of the left and right side walls of the telescopic joint b23, there are respectively an upper left pulley b261, a lower left pulley b262, an upper right pulley b and a lower right pulley b. The left connecting rope b26 is a closed loop that links the upper left pulley b261 and the lower left pulley b262. The left section of the left connecting rope b26 is fixedly connected to the third left fixed block 221, and the third left fixed block 221 is arranged near the lower end inside the telescopic joint a22. The right section of the left connecting rope b26 is connected to the fourth left fixed block 241, and the fourth left fixed block 241 is arranged near the upper end outside the telescopic joint c24. The cooperation mode of the upper right pulley a, the lower right pulley a, the right connecting rope a, the third right fixed block and the fourth right fixed block is the same as that of the upper left pulley a251, the lower left pulley a252, the left connecting rope a25, the third left fixed block 221 and the fourth left fixed block 241. When the electric telescopic measuring rod 2 needs to extend, a 24V voltage is used to supply power to the motor 27, and the motor 27 is started to make the lead screw 28 rotate clockwise. The thread on the lead screw 28 is in threaded cooperation with the thread of the through hole, driving the telescopic joint a22 to extend. Under the cooperation of the fixed pulley and the fixed block, the telescopic joint b23 extends relative to the telescopic joint a22, and the third fixed block arranged on the telescopic joint a22 moves upward relative to the telescopic joint b23, thereby driving the fourth fixed block arranged on the telescopic joint c24 to move downward and extend, realizing the extension of the electric telescopic measuring rod 2. When the electric telescopic measuring rod 2 needs to shorten, a 24V voltage is used to supply power to the motor 27, and the motor 27 is started to make the lead screw 28 rotate counterclockwise, realizing the shortening of the electric telescopic measuring rod 2. Anti-collision rubber pads 243 are arranged on the telescopic joint c24 and the housing 21 to prevent the electric telescopic measuring rod 2 from colliding with the outer surface of the stator or the rotor, damaging the device or the outer surface of the stator or the rotor. The thickness of the anti-collision rubber pad is 4.5mm.

[0046] Please refer to Figure 5 , air gap sensors 242 are respectively arranged on the left side and the right side of the expansion joint c24 for measuring the distances between the expansion joint c24 and the inner surface of the stator and the rotor poles;

[0047] Please refer to Figure 4 , the adsorption component 5 includes an electromagnet 53, a spring base 51, a reset plate 52 and a reset spring 54. The electromagnet 53 is installed on the other side of the intelligent vehicle 1. The spring base 51 is fixed on the intelligent vehicle 1 by screws. A cylindrical central shaft is clamped between the two spring bases 51. The diameter of the central shaft is the same as the inner diameter of the spring base 51. The reset spring 54 is sleeved on the central shaft. The reset plate 52 includes an upper pressing plate and a supporting plate arranged at an acute angle and a fixing hole for sleeving on the central shaft. The center line of the fixing hole coincides with the axis of the central shaft. The reset spring 54 includes a main body portion sleeved on the central shaft and two elastic feet at an angle. The elastic feet are respectively in contact with the flat plate of the spring base 51 and the upper pressing plate of the reset plate 52. The lower end of the reset plate 52 is fixedly connected with the electromagnet 53 by screws; the battery pack includes a voltage stabilizing module for supplying power to the electric components. When the electromagnet 53 is powered on, the electromagnet 53 adsorbs and presses tightly against the stator end downward. The electromagnet 53 drives the reset plate 52 to compress the reset spring 54, so that the reset spring 54 is deformed and has elastic potential energy. When the measurement is completed and the power is cut off, the reset spring 54 bounces up the reset plate 52 to drive the electromagnet 53 to lift at least 4 cm away from the stator end, without affecting the movement of the intelligent vehicle 1.

[0048] Embodiment 2

[0049] Please refer to Figure 1 and Figure 5 , a method for measuring the air gap of a hydrogenerator, which adopts the air gap measuring device in Embodiment 1. The specific measuring steps are as follows:

[0050] S1. Place the intelligent vehicle 1 on the surface of the stator such that the electric telescopic measuring rod 2 can just reach into the air gap between the stator and the rotor. According to the position of the intelligent vehicle 1, stick black tape on the stator surface, with the black tape facing the center of the vehicle. Under the action of the infrared line-tracing sensor 112, the intelligent vehicle 1 travels along the route. If it encounters an obstacle, under the action of the ultrasonic distance measuring sensor 123, the intelligent vehicle 1 stops. When the intelligent vehicle 1 travels to the center of the rotor pole, the intelligent vehicle 1 stops. Energize the adsorption component 5, and the electromagnet 53 of the adsorption component 5 adsorbs on the surface of the stator, making the intelligent vehicle 1 stable and immobile. Then start the electric telescopic measuring rod 2 and let the electric telescopic measuring rod 2 reach a certain length to start measuring.

[0051] S2. To avoid measurement errors caused by the jitter of the electric measuring telescopic rod, after it extends to the appropriate length, wait for 3 - 5 s. After the reading stabilizes, record the data. After the measurement is completed, control the motor 27 of the electric telescopic measuring rod 2 to reverse, retract the electric telescopic measuring rod 2. Then, power off the adsorption component 5, start the vehicle again, and go to the next measurement point to repeat the measurement steps.

[0052] S2. Divide the measurement range of the electric telescopic measuring rod 2 into ten equal parts on average according to its extended length, and record them as h1, h2, h3, h4, h5, h6, h7, h8, h9, h 10 , in units of mm;

[0053] S3. Record the distance measured by the left air gap sensor 242 at the current position from the rotor pole as l a , and record the distance measured by the right air gap sensor 242 at the current position from the inner surface of the stator as l b . When within the height range of h2, record the distance measured by the left air gap sensor at the current position from the rotor pole as l h2a , and record the distance measured by the right air gap sensor at the current position from the inner surface of the stator as l h2b , and so on for recording the distances at the remaining heights.

[0054] S4. Directly transmit the measured data to the display screen for processing to obtain the maximum value la a of the distance l max measured by the left air gap sensor at the current position from the rotor pole, the minimum value la min , the average value la avg , and the variance δ a

[0055]

[0056] The difference between the maximum value and the minimum value is:

[0057] la R = la max - la min The unit is mm;

[0058] The distance l measured at the current position of the right air gap sensor from the inner surface of the stator b The maximum value lb max The minimum value lb min The average value lb avg The variance δ b

[0059]

[0060] The difference between the maximum value and the minimum value is:

[0061] lb R = lb max - lb min

[0062]

[0063] Analyze the test values. If the value of the variance or the range exceeds 0.05, it is preliminarily concluded that there is a deviation in the stator or the rotor poles of the water turbine; the total thickness of the left air gap sensor, the right air gap sensor, and the expansion joint c24 is denoted as L = 11 mm. At different heights, add the distance measured at the current position of the left air gap sensor from the rotor poles, the distance measured at the current position of the right air gap sensor from the inner surface of the stator, and the thicknesses of the two air gap sensors and the expansion joint c24. That is, within the height range h1, the air gap value is calculated by the following formula: L1 = l h1a + l h1b + l The unit is mm, and the calculation method for other height ranges is the same as that within the height range h1;

[0064] S5. Compare the length L1 with the standard value of the air gap of the water turbine to determine whether it exceeds 5% of the air gap design value. If it exceeds, alarm and conduct further analysis.

[0065] Furthermore, use the infrared tracking sensor 11 and the ultrasonic ranging sensor 12 for detection. According to the actual situation on site, when the intelligent vehicle 1 deviates from the predetermined travel track by 5 cm or is 5 cm away from an obstacle, it will automatically stop and alarm on the operation interface, without the need for manual intervention, improving the measurement efficiency.

[0066] Using the air gap measurement device disclosed in the present invention, the following two measurement methods can be adopted:

[0067] 1. If the air gap measurement points of the water turbine can be determined by observation, when the trolley travels to the position to be measured, the electromagnet can be energized to fix the trolley at the measurement point, and the electric telescopic rod can be controlled to measure the rotor pole at this point. Observe and analyze the data transmitted by the sensor to determine whether there is a fault in the rotor pole. After the rotor pole is detected, start the trolley to move to the next measurement point for measurement;

[0068] 2. If the air gap measurement points cannot be determined, the trolley starts from a certain position on the stator surface, extends the telescopic rod into the air gap and maintains a certain height. Then start the trolley and use the sensor to measure the air gap at this place. Extract the minimum value from the transmitted data. The minimum value point is the position of the rotor pole. At this time, just move the trolley to this place and let the telescopic rod measure the rotor pole from top to bottom.

[0069] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for measuring the air gap of a hydrogenerator, characterized in that, Measurement is carried out using an air gap measuring device, and the air gap measuring device includes an intelligent trolley (1), an electric telescopic measuring rod (2), an adsorption component (5) and a battery pack; A sensor is provided at the front end of the intelligent trolley (1). The sensor includes an infrared tracking sensor (11) and an ultrasonic ranging sensor (12). The sensor is connected to a single-chip microcomputer inside the intelligent trolley (1). There is a motor (27) drive module on each side of the single-chip microcomputer to drive the tires of the trolley, so as to realize the transmission control of the intelligent trolley (1) for forward, backward, turning and stopping through the sensor signal - single-chip microcomputer - motor (27) drive module; The single-chip microcomputer transmits the measurement data to a computer system and displays it through a wireless transmission module; The electric telescopic measuring rod (2) is installed on one side of the intelligent trolley (1). The electric telescopic measuring rod (2) includes a housing (21), a motor (27), a lead screw (28), a telescopic section a (22), a telescopic section b (23), a telescopic section c (24) and an extension plate (4): The extension plate (4) is welded to the left side of the housing (21). The extension plate (4) is fixedly connected to the intelligent trolley (1) by screws. A support column (3) is fixedly connected to the lower part of the extension plate (4) by screws. The lower end of the support column (3) is welded to the intelligent trolley (1); The lead screw (28) is connected to the telescopic section a (22) through a threaded through hole at the top of the telescopic section a (22). There is a thread on the lead screw (28) that mates with the thread of the through hole. The motor (27) drives the lead screw (28) to rotate, thereby driving the relative telescopic movement between the telescopic section a (22) and the housing (21). The relative telescopic movement between the telescopic section a (22) and the telescopic section b (23) and between the telescopic section b (23) and the telescopic section c (24) is realized through the cooperation of a connecting rope, a fixed pulley and a fixed block; Air gap sensors (242) are respectively arranged on the left side and the right side of the telescopic section c (24). The air gap sensors (242) include a left air gap sensor and a right air gap sensor, which are used to measure the distances between the telescopic section c (24) and the inner surface of the stator and the rotor poles; The adsorption component (5) includes an electromagnet (53), a spring base (51), a reset plate (52) and a reset spring (54). The electromagnet (53) is installed on the other side of the intelligent vehicle (1). The spring base (51) is fixed to the intelligent vehicle (1) by screws. A cylindrical central shaft is sandwiched between two spring bases (51). The diameter of the central shaft is the same as the inner diameter of the spring base (51). The reset spring (54) is sleeved on the central shaft. The reset plate (52) includes an upper pressing plate and a supporting plate arranged at an acute angle and a fixing hole for sleeving on the central shaft. The center line of the fixing hole coincides with the axis of the central shaft. The reset spring (54) includes a main body portion sleeved on the central shaft and two elastic feet arranged at an angle. The elastic feet are respectively in contact with the flat plate of the spring base (51) and the upper pressing plate of the reset plate (52). The lower end of the reset plate (52) is fixedly connected to the electromagnet (53) by screws; The battery pack includes a voltage stabilizing module for supplying power to electric components; When using the air gap measuring device for measurement, the following steps are specifically included: S1. Place the intelligent vehicle (1) on the surface of the stator so that the electric telescopic measuring rod (2) can just extend into the air gap between the stator and the rotor. According to the position of the intelligent vehicle (1), stick black tape on the surface of the stator. The black tape is facing the center of the vehicle. Under the action of the infrared tracking sensor (11), the intelligent vehicle (1) travels along the route. If an obstacle is encountered, the intelligent vehicle (1) stops under the action of the ultrasonic distance measuring sensor (12); when the intelligent vehicle (1) travels to the center of the rotor pole, the intelligent vehicle (1) stops, energize the adsorption component (5), and the electromagnet (53) of the adsorption component (5) adsorbs on the surface of the stator to make the intelligent vehicle (1) stable and immovable. Then start the electric telescopic measuring rod (2) and let the electric telescopic measuring rod (2) reach a certain length to start measurement; S2. To avoid measurement errors caused by the shaking of the electric measuring telescopic rod, after extending to an appropriate length, wait for 3 - 5 s until the reading is stable and then record the data; after the measurement is completed, control the motor (27) of the electric telescopic measuring rod (2) to reverse, retract the electric telescopic measuring rod (2), then cut off the power supply of the adsorption component (5), and then start the vehicle to go to the next measurement point and repeat the measurement steps; S2. Divide the measuring range of the electric telescopic measuring rod (2) into ten equal parts according to its elongation length, and denote them as h1, h2, h3, h4, h5, h6, h7, h8, h9, h 10 , with the unit of mm; S3. Record the distance measured by the left air-gap sensor from the rotor magnetic pole at the current position as l a , and record the distance measured by the right air-gap sensor from the inner surface of the stator at the current position as l b , when within the height range of h2, record the distance measured by the left air-gap sensor from the rotor magnetic pole at the current position as l h2a , and record the distance measured by the right air-gap sensor from the inner surface of the stator at the current position as l h2b , and so on for the distance records at other heights; S4. The measured data is directly transmitted to the display screen and processed to obtain the distance l between the current position of the left air gap sensor and the rotor magnetic pole. a The maximum value of la max , minimum value la min , the average value la avg , variance δ a The difference between the maximum value and the minimum value is: la R = la max - la min The unit is mm; The distance l measured by the right air-gap sensor at the current position to the inner surface of the stator b The maximum value lb max , the minimum value lb min , the average value lb avg , the variance δ b The difference between the maximum value and the minimum value is: lb R = lb max - lb min (unit: mm); Analyze the test values. If the value of variance or range exceeds 0.05, it is preliminarily concluded that there is a deviation in the stator or rotor poles of the water turbine; the total thickness of the left air gap sensor, the right air gap sensor, and the expansion joint c (24) is denoted as L. At different heights, the distance measured by the left air gap sensor at the current position from the rotor pole and the distance measured by the right air gap sensor at the current position from the inner surface of the stator are added to the thicknesses of the two air gap sensors (242) and the expansion joint c (24). That is, within the height range h1, the air gap value is calculated according to the following formula: L1 = l h1a +l h1b +l (unit: mm). The calculation methods for other height ranges are the same as those within the height range h1; S5. Compare the length L1 with the standard value of the water turbine air gap to determine whether it exceeds 5% of the air gap design value. If it exceeds, an alarm will be given.

2. The method for measuring the air gap of a hydrogenerator according to claim 1, characterized in that, It also includes a Bluetooth module, and the Bluetooth module is used for the control of the intelligent vehicle (1) by a mobile communication device.

3. The method for measuring the air gap of a hydrogenerator according to claim 1, characterized in that, The cooperation between the connecting rope, the fixed pulley and the fixed block is specifically as follows: on the upper and lower ends of the left and right side walls of the telescopic section a (22), there are respectively an upper left pulley a (251), a lower left pulley a (252), an upper right pulley a and a lower right pulley a. The left connecting rope a (25) is a closed loop that links the upper left pulley a (251) and the lower left pulley a (252). The left section of the left connecting rope a (25) is fixedly connected to the first left fixed block (211), and the first left fixed block (211) is arranged near the lower end inside the housing (21). The right section of the left connecting rope a (25) is fixedly connected to the second left fixed block (231), and the second left fixed block (231) is arranged near the upper end outside the telescopic section b (23). The cooperation of the upper right pulley a, the lower right pulley a, the right connecting rope a, the first right fixed block, and the second right fixed block is the same as the cooperation of the upper left pulley a (251), the lower left pulley a (252), the left connecting rope a (25), the first left fixed block (211), and the second left fixed block (231). On the upper and lower ends of the left and right side walls of the telescopic section b (23), there are respectively an upper left pulley b (261), a lower left pulley b (262), an upper right pulley b and a lower right pulley b. The left connecting rope b (26) is a closed loop that links the upper left pulley b (261) and the lower left pulley b (262). The left section of the left connecting rope b (26) is fixedly connected to the third left fixed block (221), and the third left fixed block (221) is arranged near the lower end inside the telescopic section a (22). The right section of the left connecting rope b (26) is connected to the fourth left fixed block (241), and the fourth left fixed block (241) is arranged near the upper end outside the telescopic section c (24). The cooperation of the upper right pulley a, the lower right pulley a, the right connecting rope a, the third right fixed block, and the fourth right fixed block is the same as the cooperation of the upper left pulley a (251), the lower left pulley a (252), the left connecting rope a (25), the third left fixed block (221), and the fourth left fixed block (241).

4. The measuring method for the air gap of a hydrogenerator according to claim 3, characterized in that, The fixed pulley is installed on the side wall of the telescopic section through a fixed shaft provided on the telescopic section, and the linkage plane of the fixed pulley and the connecting rope is perpendicular to the side wall of the telescopic section.

5. The measuring method for the air gap of a hydrogenerator according to claim 2, characterized in that, An anti-collision rubber pad (243) is provided on the telescopic section c (24) and the housing (21).

6. The method for measuring the air gap of a hydrogenerator according to claim 5, characterized in that, The thickness of the anti-collision rubber pad (243) is 4.5 mm.

7. The method for measuring the air gap of a hydrogenerator according to claim 1, characterized in that, Using the infrared trace sensor (11) and the ultrasonic ranging sensor (12) for detection, according to the actual situation on site, when the intelligent vehicle (1) deviates from the predetermined travel track by 5 cm or is 5 cm away from an obstacle, it will automatically stop and alarm on the operation interface.

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