Water turbine set rotor hoisting centering method and system

Abstract

The invention provides a hydraulic turbine set rotor hoisting centering method which comprises the following steps: S1, surveying and mapping a hydraulic turbine set factory area, constructing a plane-coordinate system, and determining coordinates of a stator; s2, collecting positioning data of a central point location of the rotor, and calculating the moving direction and distance of the rotor; s3, moving the rotor to a position above the stator, acquiring an image from the position above the stator, identifying the image, and moving the rotor; and S4, aligning sensing units are additionally arranged on the stator and the rotor respectively, a pressure monitoring unit is additionally arranged on the stator, and the position and the moving direction of the rotor are finely adjusted. The invention further provides a hydraulic turbine set rotor hoisting and centering system which is used for implementing the hydraulic turbine set rotor hoisting and centering method. The technical problems that the operation of hoisting the water turbine rotor to the stator pit is inconvenient and the operation efficiency is low are solved, and the technical effects that a large amount of manpower is prevented from being input in the water turbine operation and maintenance process, and the automation degree and the working efficiency of hoisting the rotor to the stator pit are improved are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydroelectric power generation, and particularly relates to a method for hoisting and centering a rotor of a hydro-turbine unit and a system for hoisting and centering the rotor of the hydro-turbine unit. BACKGROUND

[0002] As one of the main control devices for modern power production, the core function of a water turbine is to convert water energy into mechanical energy, thereby providing necessary equipment conditions for power generation. However, in the process of operation and maintenance of the water turbine, the rotor of the water turbine generator has a large geometric size and equipment tonnage, which makes the hoisting operation difficult and risky. In addition, the allowable gap between the rotor and the stator is small during hoisting, and the rotor needs to be hoisted with a certain centering accuracy to avoid equipment damage accidents caused by extrusion and collision.

[0003] Currently, when the rotor of the hydro-turbine unit is hoisted out or the stator is reinstalled, a worker is arranged at each magnetic pole of the rotor to hold a wooden plug and continuously pull it up and down, so as to timely find out whether the stator and the rotor are in contact. Meanwhile, the hoisting commander continuously adjusts the position of the hoisting equipment according to the contact position until the rotor is completely lowered into the stator pit. The current operation of hoisting the rotor of the water turbine into the stator pit requires a large number of workers to work together, which is inconvenient and inefficient, and has certain safety hazards. SUMMARY

[0004] In view of the deficiencies in the prior art, the present application provides a method and system for hoisting and centering a rotor of a hydro-turbine unit, which solves the problems of inconvenient operation and low efficiency in hoisting the rotor of the water turbine into the stator pit in the prior art.

[0005] According to an embodiment of the present application, a method for hoisting and centering a rotor of a hydro-turbine unit comprises the following steps,

[0006] S1, mapping the hydro-turbine unit plant area and constructing a plane coordinate system of the hydro-turbine unit plant area, and determining the coordinates of the stator in the plane coordinate system;

[0007] S2, collecting positioning data of the center point of the rotor in the plane coordinate system, and calculating the moving direction and distance of the rotor according to the positioning data of the center point of the rotor and the coordinates of the rotor;

[0008] S3, moving the rotor above the stator according to the moving direction and distance of the rotor calculated in step S2, collecting images of the rotor and the stator from above the rotor, identifying and extracting the edge features of the rotor and the edge features of the stator from the collected images, calculating the distance between the center point of the rotor and the center point of the stator, and moving the rotor until the center point of the rotor coincides with the center point of the stator according to the calculated distance between the center point of the rotor and the center point of the stator.

[0009] S4, respectively installing alignment sensing units on the stator and the rotor, and installing a pressure monitoring unit on the stator, collecting signals emitted by the alignment sensing units and signals emitted by the pressure monitoring unit during the process that the rotor falls into the stator, and fine-tuning the position and moving direction of the rotor according to the signals emitted by the alignment sensing units and the signals emitted by the pressure monitoring unit, until the rotor completely falls into the stator.

[0010] In another aspect, according to the embodiment of the present application, a water turbine set rotor hoisting centering system is also provided for implementing the above-mentioned water turbine set rotor hoisting centering method, which comprises a control module, an upper computer unit, a positioning unit, alignment sensing units, a pressure monitoring unit, an image acquisition unit and a signal acquisition unit, the control module is electrically connected with the upper computer unit, the signal acquisition unit is in communication connection with the upper computer unit, the positioning unit, the alignment sensing units, the pressure monitoring unit and the image acquisition unit are electrically connected with the signal acquisition unit respectively, the positioning unit is installed on the rotor, the alignment sensing units are installed on the stator and the rotor, the pressure monitoring unit is installed on the stator, and the image acquisition unit is installed directly above the rotor.

[0011] Compared with the prior art, the present application has the following beneficial effects: by adopting the surveying and mapping and constructing the plane coordinate system of the water turbine set factory area, determining the coordinates of the stator in the plane coordinate system and collecting the positioning data of the center point position of the rotor in the plane coordinate system to calculate the moving direction and distance of the rotor moving to the upper side of the stator, collecting the images of the rotor and the stator after the rotor moves to the upper side of the stator, extracting and calculating the distance between the center point position of the rotor and the center point position of the stator by identifying the images, and moving the rotor according to the calculated distance between the center point position of the rotor and the center point position of the stator, the center point position of the rotor can coincide with the center point position of the stator, at this time, the center point position of the rotor is aligned with the center point position of the stator, and the rotor can fall into the pit of the stator by operating the rotor to fall down, and during the process that the rotor falls down, the alignment sensing units respectively arranged on the rotor and the stator monitor whether the rotor keeps aligned with the stator during the falling process, and the pressure monitoring unit arranged on the stator monitors whether the rotor contacts or collides with the stator, so as to ensure that the rotor falls smoothly into the pit of the stator, which solves the technical problems of inconvenient operation and low operation efficiency of hoisting the water turbine rotor to the pit of the stator, produces the technical effects of avoiding investing a large amount of manpower during the operation and maintenance of the water turbine, improving the automation degree and work efficiency of hoisting the rotor to the pit of the stator, and protecting and regulating during the process that the rotor falls into the pit of the stator to avoid safety accidents. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 The flowchart of the water turbine set rotor hoisting centering method of the embodiment one of the present application;

[0013] Figure 2 FIG. 1 is a schematic diagram of the plane coordinate system constructed in step S1 of the method for hoisting and centering the rotor of the hydraulic turbine unit according to the first embodiment of the present application;

[0014] Figure 3 FIG. 2 is a structural schematic diagram of the hoisting and centering system for the rotor of the hydraulic turbine unit according to the second embodiment of the present application;

[0015] Figure 4 FIG. 3 is a schematic diagram of the part of the structure of the hoisting and centering system for the rotor of the hydraulic turbine unit according to the first embodiment of the present application installed on the rotor and the stator;

[0016] Figure 5 FIG. 4 is a schematic diagram of the part of the structure of the hoisting and centering system for the rotor of the hydraulic turbine unit according to the second embodiment of the present application installed on the rotor;

[0017] Figure 6 FIG. 5 is a schematic diagram of the part of the structure of the hoisting and centering system for the rotor of the hydraulic turbine unit according to the second embodiment of the present application installed on the stator.

[0018] In the above figures: 1, alignment sensing unit; 2, pressure monitoring unit; 3, signal acquisition unit; 4, upper computer unit; 5, control module; 6, positioning unit; 7, rotor; 8, stator; 9, bridge crane; 10, image acquisition unit. DETAILED DESCRIPTION

[0019] The technical solutions in the present application will be further described below with reference to the accompanying drawings and embodiments.

[0020] Embodiment 1

[0021] As shown in FIGS. 1, 2, 3, 4 and 5, the first embodiment of the present application proposes a method for hoisting and centering the rotor of the hydraulic turbine unit, which comprises the following steps: Figure 1 Figure 2 Figure 4 S1, mapping the factory area of the hydraulic turbine unit and constructing the plane coordinate system of the factory area of the hydraulic turbine unit, and determining the coordinates of the stator 8 in the plane coordinate system;

[0022] S2, collecting the positioning data of the center point of the rotor 7 in the plane coordinate system, and calculating the moving direction and distance of the rotor 7 according to the positioning data of the center point of the rotor 7 and the coordinates of the stator 8;

[0023] S3, moving the rotor 7 to the position corresponding to the center point of the rotor 7 in the plane coordinate system according to the moving direction and distance of the rotor 7 calculated in step S2, and determining the center point of the rotor 7 in the plane coordinate system;

[0024] ​​S3, moving the rotor 7 to above the stator 8 according to the moving direction and distance of the rotor 7 calculated in step S2, collecting images of the rotor 7 and the stator 8 from above the rotor 7 after the rotor 7 is moved to above the stator 8, extracting edge features of the rotor 7 and edge features of the stator 8 by identifying the collected images, calculating a distance between a center point of the rotor 7 and a center point of the stator 8, and moving the rotor 7 according to the calculated distance between the center point of the rotor 7 and the center point of the stator 8 until the center point of the rotor 7 coincides with the center point of the stator 8;

[0025] S4, installing the alignment sensing unit 1 on the stator 8 and the rotor 7 respectively, and installing the pressure monitoring unit 2 on the stator 8, collecting signals emitted by the alignment sensing unit 1 and signals emitted by the pressure monitoring unit 2 respectively during the process that the rotor 7 falls into the stator 8, and fine-tuning the position and moving direction of the rotor 7 according to the signals emitted by the alignment sensing unit 1 and the signals emitted by the pressure monitoring unit 2 until the rotor 7 completely falls into the stator 8.

[0026] Specifically, the water turbine set rotor hoisting centering method provided in the embodiment determines the coordinates of the stator 8 in the plane coordinate system and collects positioning data of the center point of the rotor 7 in the plane coordinate system by surveying and constructing the plane coordinate system of the water turbine set factory site, calculates the moving direction and distance of the rotor 7 to move to above the stator 8 according to the coordinates of the stator 8 and the coordinates of the center point of the rotor 7, moves the rotor 7 to above the stator 8, collects images of the rotor 7 and the stator 8 from above after the rotor 7 is moved to above the stator 8, extracts the center point of the rotor 7 and the center point of the stator 8 by identifying the images, and calculates the distance between the center point of the rotor 7 and the center point of the stator 8, so as to move the rotor 7 according to the calculated distance between the center point of the rotor 7 and the center point of the stator 8 to make the center point of the rotor 7 coincide with the center point of the stator 8, thereby aligning the center point of the rotor 7 with the center point of the stator 8, and then operating the rotor 7 to fall into the pit of the stator 8, and the alignment sensing unit 1 arranged on the rotor 7 and the stator 8 respectively monitors whether the rotor 7 keeps aligned with the stator 8 during the falling process, and the pressure monitoring unit 2 arranged on the stator 8 monitors whether the rotor 7 contacts or collides with the stator 8, so as to ensure that the rotor 7 falls smoothly into the pit of the stator 8. The water turbine set rotor hoisting centering method provided in the embodiment can find the pit of the stator 8 by itself and move the rotor 7 to above the stator 8 during hoisting the rotor 7, and automatically align the center point of the rotor 7 with the center point of the stator 8 by image recognition, so that the rotor 7 can fall smoothly into the pit of the stator 8, and the rotor 7 is protected and regulated during the process that the rotor 7 falls into the pit of the stator 8, without the need to invest a large amount of manpower during operation and maintenance, thereby improving the automation degree and work efficiency of hoisting the rotor 7 to the pit of the stator 8, and avoiding safety accidents.

[0027] AsFigure 2 As shown, in step S1, a planar coordinate system of the hydro-turbine unit plant area is constructed with any point in the hydro-turbine unit plant area as the origin, the moving direction of the bridge of the bridge crane 9 hoisting the rotor 7 as the X axis, and the moving direction of the trolley of the bridge crane 9 hoisting the rotor 7 as the Y axis. The mapping methods include but are not limited to manual tape mapping, three-dimensional laser scanning mapping, and total station mapping, and the coordinates of the stator 8 are plotted based on the position of the center point of the stator 8.

[0028] Please refer to Figure 1 Step S3 includes step S31, image preprocessing, converting the RGB image to a grayscale image, and the calculation formula is

[0029] I(x, y) = 0.299R(x, y) + 0.587G(x, y) + 0.1148B(x, y)

[0030] wherein I(x, y) is the pixel value of the grayscale image at coordinates (x, y), R(x, y) is the pixel value of the red channel of the image at coordinates (x, y), G(x, y) is the pixel value of the green channel of the image at coordinates (x, y), and B(x, y) is the pixel value of the blue channel of the image at coordinates (x, y);

[0031] Then the image is smoothed using a Gaussian kernel to suppress noise:

[0032] I blur (x, y) = I(x, y) * Gσ(x, y)

[0033] wherein σ controls the smoothing degree, I blur (x, y) is the pixel value of the image after high filtering at coordinates (x, y).

[0034] Further, step S31 includes step S32, edge detection, extracting the contour information of the rotor 7 and the stator 8 in the image, and using the Sobel operator to calculate the horizontal and vertical gradients:

[0035]

[0036] wherein G x is the horizontal gradient, and G y is the vertical gradient; the gradient amplitude and direction are calculated:

[0037]

[0038] wherein is the gradient vector of the image, and θ is the gradient direction;

[0039] The local maximum pixel in the gradient direction is retained, the edge is refined, and double threshold detection is used to generate a binary edge map E(x,y).

[0040] Furthermore, step S32 includes step S33, Hough circle detection, detecting the parameters (a, b, r) of the circle in the parameter space. The parametric equation of the circle is:

[0041] (xa) 2 +(yb) 2 =r 2

[0042] Where (a, b) is the coordinate of the center of the circle, and r is the radius; construct a three-dimensional accumulator A(a, b, r), count the possible circle parameters, and then for each edge point (x i ,y i ), along the gradient direction θ i Search for the center of the circle:

[0043] a=x i -rcosθ i , b=y i -rsinθ i

[0044] In the radius range [r min , r max ] traverse r in the loop, update the accumulator A(a, b, r), find the local maximum value in the accumulator, correspond to the candidate circle parameters, merge the overlapping candidate circles through non-maximum suppression, and extract the coordinates and radius of the rotor 7 and stator 8 based on the determination of the circle center.

[0045] like Figure 1 and Figure 4 As shown, step S4 also includes step S41, judging whether the alignment sensor unit 1 is turned on according to whether the signal transmitted by the alignment sensor unit 1 is received. If the signal transmitted by the alignment sensor unit 1 is received, the alignment sensor unit 1 is turned on. At this time, the rotor 7 and the stator 8 are aligned, and the rotor 7 can continue to fall. If the signal transmitted by the alignment sensor unit 1 is not received, the alignment sensor unit 1 is not turned on. At this time, the rotor 7 and the stator 8 are not aligned, and step S2 needs to be re-executed until the alignment sensor unit 1 is turned on.

[0046] In detail, the step S4 further comprises a step S42, judging whether the rotor 7 produces deviation in the falling process according to whether the signal transmitted by the pressure monitoring unit 2 is received. If the signal transmitted by the pressure monitoring unit 2 is not received, the deviation degree of the rotor 7 is still within the controllable range, and the falling can be continued. If the signal transmitted by the pressure monitoring unit 2 is received, a pressure threshold is set in advance, the deviation amount and the deviation direction of the rotor 7 are judged according to the change amount of the pressure data monitored by the pressure monitoring unit 2 and the position where the pressure data on the stator 8 changes, the rotor 7 is controlled to move in the opposite direction of the deviation direction in the falling process until the signal transmitted by the pressure monitoring unit 2 is not received again when the change amount of the pressure data is within the pressure threshold, and the rotor 7 is stopped from falling and reversely moved in the deviation direction until the change amount of the pressure data is adjusted to be within the pressure threshold when the change amount of the pressure data exceeds the pressure threshold, the rotor 7 is controlled to continue falling while moving in the opposite direction of the deviation direction until the signal transmitted by the pressure monitoring unit 2 is not received again after the change amount of the pressure data is adjusted to be within the pressure threshold.

[0047] Embodiment two

[0048] As shown in Figures 3 to 6 Embodiment two of the present application proposes a hoisting and centering system for the rotor of a hydraulic turbine unit, which is used to implement the method for hoisting and centering the rotor of a hydraulic turbine unit according to Embodiment one.

[0049] As shown in Figure 3As shown, the water turbine rotor hoisting centering system comprises a control module 5, an upper computer unit 4, a positioning unit 6, a centering sensing unit 1, a pressure monitoring unit 2, an image acquisition unit 10 and a signal acquisition unit 3, the upper computer unit 4 is used for constructing a plane coordinate system, inputting the coordinates of the stators 8 and analyzing and displaying the positional relationship between the rotor 7 and the stators 8, when the number of the stators 8 is two or more, the upper computer unit 4 can number each stator 8 and record the coordinates of the corresponding numbered stator 8, the control module 5 is electrically connected with the upper computer unit 4, the control module 5 is used for being connected with a bridge crane 9 hoisting the rotor 7 and sending a driving command to the bridge crane 9 under the instruction of the upper computer unit 4, so as to control the speed and direction of the bridge crane 9 moving the rotor 7, the signal acquisition unit 3 is in communication connection with the upper computer unit 4, the positioning unit 6, the centering sensing unit 1, the pressure monitoring unit 2 and the image acquisition unit 10 are electrically connected with the signal acquisition unit 3, the positioning unit 6 is installed on the rotor 7, the positioning unit 6 is used for collecting the positioning data of the rotor 7 and sending to the signal acquisition unit 3, the centering sensing unit 1 is installed on the stator 8 and the rotor 7, the centering sensing unit 1 is used for monitoring whether the rotor 7 and the stator 8 are kept in centering, the pressure monitoring unit 2 is installed on the stator 8, the pressure monitoring unit 2 is used for monitoring whether the rotor 7 contacts or collides with the stator 8, the image acquisition unit 10 is installed directly above the rotor 7, the image acquisition unit 10 is used for shooting the images of the rotor 7 and the stator 8 and sending to the signal acquisition unit 3, the signal acquisition unit 3 collects the signals collected by the positioning unit 6, the centering sensing unit 1, the pressure monitoring unit 2 and the image acquisition unit 10 and transmits to the upper computer unit 4.

[0050] Please refer to Figure 4 , Figure 5 and Figure 6 , the centering sensing unit 1 comprises at least one of a photoelectric opposite shooting switch, a laser opposite shooting switch and a visual centering system. In the embodiment, the centering sensing unit 1 selects a laser centering switch, which is respectively installed at the bottom of the rotor 7 and the corresponding position of the stator 8, and the number of the laser centering switch is four, the four laser centering switches are arranged along the circumference of the rotor 7, and the four laser centering switches are respectively turned on when the rotor 7 is centered with the stator 8.

[0051] Please combine Figure 4 , Figure 5 and Figure 6The pressure monitoring unit 2 comprises at least one of a strain gauge, an optical fiber strain sensor and an ultra-weak fiber grating strain sensor, and the surface of the pressure monitoring unit 2 is covered with a flat plate buffer, which can be made of silica gel, carbon fiber, rubber or other materials that are easy to be plastic and have pressure resistance effect, so as to play a buffering role. In the embodiment, the flat plate buffer is made of silica gel, the thickness of the flat plate buffer is not greater than the width of the gap between the rotor 7 and the stator 8, and the ultra-weak fiber grating stress sensor is embedded in the flat plate buffer. The flat plate buffer made of silica gel can fill the gap between the rotor 7 and the stator 8 to play a protection role, preventing the rotor 7 and the stator 8 from colliding and being damaged.

[0052] Specifically, the pressure monitoring unit 2 is arranged according to the number of magnetic poles on the rotor 7, and in the embodiment, the pressure monitoring unit 2 is installed on the edge of the stator 8.

[0053] As shown in Figure 3 , the control module 5 is in communication connection with the original walking driving module and the equipment state monitoring module of the bridge crane 9. The control module 5 sends driving commands and speed to the walking driving module of the bridge crane 9 according to the control instruction of the upper computer unit 4, and the walking driving module controls the driving motor of the bridge crane 9 to adjust the speed and direction of the walking of the bridge crane 9, so as to realize the control of the moving direction and distance of the rotor 7.

[0054] As shown in Figure 3 , the positioning unit 6 can be one of the positioning systems such as laser, encoder, code band and WCS, and can also directly obtain positioning data from the PLC electrical control system and the equipment safety monitoring system of the hydroelectric generating set factory area which have positioning data.

[0055] Please refer to Figure 3 , the image acquisition unit 10 adopts a camera, and the camera is installed above the hook of the bridge crane 9, so as to ensure that the camera can shoot the clear edges of the rotor 7 and the stator 8.

[0056] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the present application, and all of them should be covered in the scope of the claims of the present application.

Claims

1. A method for hoisting and centering a turbine rotor, characterized by: The following steps are included: S1. Survey and map the turbine plant area and construct a plane coordinate system for the turbine plant area, and determine the coordinates of the stator in the plane coordinate system; S2. Collecting the positioning data of the center point of the rotor in the plane coordinate system, and calculating the moving direction and distance of the rotor based on the positioning data of the center point of the rotor and the coordinates of the stator; S3. Move the rotor above the stator according to the movement direction and distance of the rotor calculated in step S2, capture images of the rotor and the stator from above the rotor, identify and extract edge features of the rotor and the stator from the captured images, calculate the distance between the center point of the rotor and the center point of the stator, and move the rotor according to the calculated distance between the center point of the rotor and the center point of the stator until the center point of the rotor coincides with the center point of the stator; S4. Install an alignment sensing unit on the stator and rotor respectively, and install a pressure monitoring unit on the stator. During the process of the rotor falling into the stator, collect the signals emitted by the alignment sensing unit and the pressure monitoring unit respectively, and fine-tune the position and movement direction of the rotor according to the signals emitted by the alignment sensing unit and the pressure monitoring unit until the rotor completely falls into the stator.

2. A method for hoisting and centering a turbine rotor according to claim 1, characterized in that: In step S1, a plane coordinate system of the turbine plant is constructed with any point in the turbine plant as the origin, the moving direction of the bridge of the bridge crane for hoisting the rotor as the X-axis, and the moving direction of the hoisting trolley of the bridge crane for hoisting the rotor as the Y-axis.

3. The method for hoisting and centering a turbine rotor according to claim 1, wherein: Step S3 includes step S31, image preprocessing, converting the RGB image into a grayscale image, and the calculation formula is I(x,y)=0.299R(x,y)+0.587G(x,y)+0.114B(x,y) Where I(x, y) is the pixel value of the grayscale image at coordinate (x, y), R(x, y) is the pixel value of the red channel of the image at coordinate (x, y), G(x, y) is the pixel value of the green channel of the image at coordinate (x, y), and B(x, y) is the pixel value of the blue channel of the image at coordinate (x, y). Then use Gaussian kernel to smooth the image and suppress noise: I blur (x,y)=I(x,y)*G σ (x,y) in, σ controls the degree of smoothness, I blur (x, y) is the pixel value of the high-filtered image at coordinate (x, y).

4. A method for hoisting and centering a turbine rotor according to claim 3, characterized in that: Step S31 is followed by step S32, edge detection, extracting the contour information of the rotor and stator in the image, and calculating the horizontal and vertical gradients using the Sobel operator: Among them, G x is the horizontal gradient, G y is the gradient in the vertical direction; calculate the gradient magnitude and direction: in, is the gradient vector of the image, θ is the gradient direction; The local maximum pixel in the gradient direction is retained, the edge is refined, and double threshold detection is used to generate a binary edge map E(x,y).

5. A method for hoisting and centering a turbine rotor according to claim 4, characterized in that: Step S32 is followed by step S33, Hough circle detection, which detects the parameters (a, b, r) of the circle in the parameter space. The parametric equation of the circle is: (x-a) 2 +(y-b) 2 =r 2 Where (a, b) is the coordinate of the center of the circle, and r is the radius; construct a three-dimensional accumulator A(a, b, r), count the possible circle parameters, and then for each edge point (x i ,y i ), along the gradient direction θ i Search for the center of the circle: a=x i -rcosθ i ,b=y i -rsinθ i In the radius range [r min , r max ] traverse r in the loop, update the accumulator A(a, b, r), find the local maximum value in the accumulator, correspond to the candidate circle parameters, merge the overlapping candidate circles through non-maximum suppression, and extract the coordinates and radius of the rotor and stator based on the determination of the circle center.

6. The method for hoisting and centering a turbine rotor according to claim 1, characterized in that: Step S4 also includes step S41, judging whether the alignment sensor unit is turned on based on whether a signal transmitted by the alignment sensor unit is received. If the signal transmitted by the alignment sensor unit is received, the alignment sensor unit is turned on, and the rotor and the stator are aligned at this time, and the rotor can continue to fall; if the signal transmitted by the alignment sensor unit is not received, the alignment sensor unit is not turned on, and the rotor and the stator are not aligned at this time, and step S2 needs to be re-executed until the alignment sensor unit is turned on.

7. The method for hoisting and centering a turbine rotor according to claim 1, characterized in that: Step S4 also includes step S42, judging whether the rotor is offset during the falling process based on whether the signal transmitted by the pressure monitoring unit is received. If the signal transmitted by the pressure monitoring unit is not received, the offset degree of the rotor is still within the controllable range and can continue to fall; if the signal transmitted by the pressure monitoring unit is received, a pressure threshold is set in advance, and the offset and offset direction of the rotor are judged based on the change in pressure data monitored by the pressure monitoring unit and the position where the pressure data on the stator changes. When the change in pressure data is within the pressure threshold, the rotor is controlled to move in the opposite direction of the offset direction during the falling process until the signal transmitted by the pressure monitoring unit is no longer received. When the change in pressure data exceeds the pressure threshold, the rotor is stopped from falling and moved in the opposite direction of the deviation until the change in pressure data is adjusted to within the pressure threshold. After the change in pressure data is adjusted to within the pressure threshold, the rotor is controlled to continue falling while moving in the opposite direction of the offset direction until the signal transmitted by the pressure monitoring unit is no longer received.

8. A hydro turbine rotor hoisting and centering system, characterized by: A method for hoisting and centering a turbine rotor according to any one of claims 1 to 7, comprising a control module, a host computer unit, a positioning unit, an alignment sensor unit, a pressure monitoring unit, an image acquisition unit, and a signal acquisition unit, wherein the control module is electrically connected to the host computer unit, the signal acquisition unit is communicatively connected to the host computer unit, the positioning unit, the alignment sensor unit, the pressure monitoring unit, and the image acquisition unit are respectively electrically connected to the signal acquisition unit, the positioning unit is mounted on the rotor, the alignment sensor unit is mounted on the stator and the rotor, the pressure monitoring unit is mounted on the stator, and the image acquisition unit is mounted directly above the rotor.

9. A hydro-turbine rotor hoisting and centering system according to claim 8, characterized in that: The alignment sensing unit includes at least one of a photoelectric alignment switch, a laser alignment switch and a visual alignment system.

10. The hydro-turbine rotor hoisting and centering system according to claim 8, characterized in that: The pressure monitoring unit includes at least one of a strain gauge, an optical fiber strain sensor, and an ultra-weak fiber Bragg grating strain sensor.

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