A method for determining the height of a rotor magnetic pole of a large-scale axial flow variable-pitch unit

Abstract

The application discloses a large-scale axial flow variable-pitch unit rotor magnetic pole height determination method, wherein a magnetic pole T tail of the magnetic pole is matched with a magnetic yoke T tail groove of the magnetic yoke; the magnetic pole and the magnetic yoke are fixed in a radial direction position by a magnetic pole key; axial direction positions of the magnetic pole and the magnetic yoke are limited by a magnetic pole stopper; magnetic pole height adjustment is realized by adjusting up and down positions of the magnetic pole stopper; a magnetic pole center line height is deviated from a stator core center line average height within ±2mm, and height deviations of 110 magnetic poles are within ±1.5mm; the method specifically comprises the following steps: step 1, determination of the magnetic pole center line height; step 2, determination of a magnetic pole stopper distance from a rotor brake ring plate B point height; step 3, adjustment and welding of the magnetic pole stopper height; and step 4, installation of the magnetic pole. The method is used to determine the height in the rotor magnetic pole reconstruction process, improves the efficiency and precision of the rotor magnetic pole height adjustment, and reduces the workload.

Description

Technical Field

[0001] This invention relates to the field of hydropower equipment retrofitting technology, and in particular to a method for determining the elevation of rotor magnetic poles in a large axial-flow propeller turbine unit. Background Technology

[0002] A hydroelectric power station with an axial-flow propeller turbine unit has been in operation for nearly 40 years. The equipment is severely aged and its performance has deteriorated, necessitating a complete overhaul and upgrade. According to the upgrade plan, the rotor poles need to be replaced entirely. National standards stipulate that the average elevation deviation between the rotor pole centerline and the stator core centerline should be within ±2mm, and the deviation of all 110 poles should not exceed ±1.5mm. Traditional installation methods require installing all poles, tightening the pole keys, and then measuring the pole centerline elevation, adjusting any that do not meet the requirements. This method is extremely cumbersome, requiring elevation measurements for each pole during installation, repeated adjustments based on the data, and significant workload after tightening the pole keys. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a method for determining the elevation of rotor magnetic poles during the modification process of large axial-flow propeller turbine units. This method is used to determine the elevation during the modification process of rotor magnetic poles, thereby effectively improving the efficiency and accuracy of rotor magnetic pole elevation adjustment and reducing workload.

[0004] To achieve the aforementioned technical effects, the objective of this invention is as follows: A method for determining the elevation of rotor magnetic pole modification in a large axial-flow propeller turbine unit: The magnetic pole T-tail of the magnetic pole mates with the magnetic yoke T-tail groove; the magnetic pole and the magnetic yoke are fixed in the radial direction by a magnetic pole key; the axial direction of the magnetic pole and the magnetic yoke is limited by a magnetic pole stop block. The magnetic pole height can be adjusted by adjusting the up and down position of the magnetic pole stop. The average elevation deviation between the magnetic pole centerline and the stator core centerline is within ±2mm, and the elevation deviation of the 110 magnetic poles is within ±1.5mm. The method specifically includes the following steps: Step 1, Determining the elevation of the magnetic pole centerline; Step 2, determining the height of the magnetic pole stop block from point B on the rotor brake ring plate; Step 3: Adjusting and welding the height of the magnetic pole stop; Step 4, Installing the magnetic poles.

[0005] The specific steps of step 1 are as follows: Step 1.1: After the unit is fully rotated before overhaul and all data meet the technical requirements for rotation, and the air damper is in the reset state, measure the distance between the air damper base plate and the rotor brake ring plate. Set a point on the air damper base plate, defined as A; define B on the plane within the range of the rotor brake ring plate vertically above this point; measure the distance m between points A and B using an inside micrometer. Step 1.2: After the stator core modification is completed, measure the distance k from the center line of the stator core to point A on the wind gate foundation plate; Step 1.3: Based on the principle of consistent stator core centerline elevation, the distance from the rotor magnetic pole centerline to point A is H; Step 1.4, the distance from the rotor magnetic pole centerline to point B on the rotor brake ring plate. j = k - m .

[0006] The specific steps of step 2 are as follows: Step 2.1, Measure the length of the T-tail of each magnetic pole. L i ; Step 2.2, the distance from the upper surface of each magnetic pole stop block to point B on the rotor brake ring plate. n i = j - L i / 2.

[0007] The specific steps of step 3 are as follows: Based on the calculated height of the corresponding magnetic pole stop from point B on the rotor brake ring plate n i When installing the magnetic pole stop, the height of the magnetic pole stop should deviate from the theoretical value by within 0.30mm.

[0008] The specific steps of step 4 are as follows: After the magnetic pole stop is installed, hang the magnetic pole, tighten the magnetic pole key, measure the elevation of the magnetic pole centerline, and reprocess the magnetic poles whose elevation of the magnetic pole centerline exceeds the tolerance.

[0009] The present invention has the following beneficial effects: 1. The method of this invention controls the elevation of the magnetic pole centerline by adjusting the installation data of the stop block. It is simple to operate and highly efficient.

[0010] 2. The installation method of this invention can reduce the number of times the magnetic poles are hoisted and reduce the risk of magnetic pole loss.

[0011] 3. By applying this method to the rotor magnetic pole modification of a hydropower station, the elevation of 110 magnetic poles was successfully installed in one go, saving 10 days of construction time. Attached Figure Description

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a schematic diagram of the magnetic pole mounting structure.

[0014] Figure 2 for Figure 1 AA view.

[0015] Figure 3 A schematic diagram for determining the elevation of the magnetic pole centerline.

[0016] In the diagram: Magnetic pole 1, Magnetic yoke 2, Magnetic pole T-tail 3, Magnetic yoke T-tail groove 4, Magnetic pole stop block 5, Air damper base plate 6, Rotor brake ring plate 7, Stator core center line 8, Rotor magnetic pole center line 9. Detailed Implementation

[0017] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0018] Example 1: See Figure 1-2 A method for determining the elevation of rotor magnetic pole modification in a large axial-flow propeller turbine unit: The magnetic pole T-tail 3 of magnetic pole 1 mates with the magnetic yoke T-tail groove 4 of magnetic yoke 2; magnetic pole 1 and magnetic yoke 2 are fixed in radial direction by magnetic pole keys; the axial direction of magnetic pole 1 and magnetic yoke 2 is limited by magnetic pole stops 5; the height of magnetic pole 1 is adjusted by adjusting the vertical position of magnetic pole stops 5; the average elevation deviation between the centerline elevation of magnetic pole 1 and the centerline elevation of the stator core is within ±2mm, and the elevation deviation of the 110 magnetic poles is within ±1.5mm. Since the requirements for magnetic pole elevation deviation are high during the modification process, this method can effectively solve the problem of elevation determination.

[0019] Example 2: See 3. The method specifically includes the following steps: Step 1, Determining the elevation of the centerline of magnetic pole 1: Step 1.1: After the unit is fully rotated before overhaul and all data meet the technical requirements for rotation, and the air damper is in the reset state, measure the distance between the air damper base plate 6 and the rotor brake ring plate 7. Set a point on the air damper base plate 6, defined as A; define B on the plane within the range of the rotor brake ring plate 7 vertically above this point; measure the distance m between points A and B using an inside micrometer. Step 1.2: After the stator core modification is completed, measure the distance k between the center line 8 of the stator core and point A on the wind gate foundation plate 6. Step 1.3, based on the principle that the stator core centerline 8 has the same elevation, the distance from the rotor magnetic pole centerline 9 to point A is H; Step 1.4, the distance between the rotor magnetic pole centerline 9 and point B on the rotor brake ring plate 7. j = k - m .

[0020] Step 2, determining the height of the magnetic pole stop 5 from point 7B of the rotor brake ring plate: Step 2.1, measure the length of the tail 3 of each magnetic pole T. L i ; Step 2.2, the distance from the upper surface of each magnetic pole stop 5 to point B on the rotor brake ring plate 7. n i = j - L i / 2.

[0021] Step 3, Adjustment and welding of the height of magnetic pole stop 5: Based on the calculated distance between the corresponding magnetic pole stop 5 and point B on the rotor brake ring plate 7 n i The data is installed with magnetic pole stop 5, and the height of magnetic pole stop 5 is required to deviate from the theoretical value within 0.30mm.

[0022] Step 4, Installation of Magnetic Pole 1: After the magnetic pole stop block 5 is installed, the magnetic pole 1 is hung up, the magnetic pole key is tightened, the elevation of the magnetic pole center line is measured, and the magnetic poles whose elevation of the magnetic pole center line exceeds the tolerance are reprocessed.

Claims

1. A method for determining the elevation of rotor magnetic pole modification in a large axial-flow propeller turbine unit, characterized in that: The magnetic pole T-tail (3) of the magnetic pole (1) is matched with the magnetic yoke T-tail groove (4) of the magnetic yoke (2); the magnetic pole (1) and the magnetic yoke (2) are fixed in the radial direction by magnetic pole key; the axial direction of the magnetic pole (1) and the magnetic yoke (2) is limited by magnetic pole stop (5); The height of the magnetic pole (1) can be adjusted by adjusting the up and down position of the magnetic pole stop (5); The elevation of the center line of the magnetic pole (1) deviates from the average elevation of the center line of the stator core within ±2mm, and the elevation deviation of the 110 magnetic poles is within ±1.5mm. The method specifically includes the following steps: Step 1, Determining the elevation of the centerline of the magnetic pole (1); Step 2, Determining the height of the magnetic pole stop (5) from point B of the rotor brake ring plate (7); Step 3, Adjustment and welding of the height of the magnetic pole stop (5); Step 4, Installation of magnetic pole (1); The specific steps of step 1 are as follows: Step 1.1: After the unit is fully rotated before overhaul and all data meet the technical requirements for rotation, and the air damper is in the reset state, measure the distance between the air damper base plate (6) and the rotor brake ring plate (7). Set a point on the air damper base plate (6) and define it as A; define B on the plane within the range of the rotor brake ring plate (7) vertically above this point; measure the distance m between points A and B using an inside micrometer. Step 1.2: After the stator core modification is completed, measure the distance k between the center line (8) of the stator core and point A on the wind gate foundation plate (6); Step 1.3, according to the principle that the center line (8) of the stator core is consistent with the elevation, the distance between the center line (9) of the rotor magnetic pole and point A is H; Step 1.4, the distance between the rotor magnetic pole centerline (9) and point B on the rotor brake ring plate (7) j = k - m ; The specific steps of step 2 are as follows: Step 2.1, measure the length of the tail of each magnetic pole T (3). L i ; Step 2.2, the distance from the upper surface of each magnetic pole stop (5) to point B on the rotor brake ring plate (7) n i = j - L i / 2; The specific steps of step 3 are as follows: Based on the calculated distance of the corresponding magnetic pole stop (5) from point B on the rotor brake ring plate (7) n i Install the magnetic pole stop (5) according to the data, and require that the height of the magnetic pole stop (5) deviates from the theoretical value within 0.30mm; The specific steps of step 4 are as follows: After the magnetic pole stop block (5) is installed, the magnetic pole (1) is hung up, the magnetic pole key is tightened, the elevation of the magnetic pole center line is measured, and the magnetic poles whose elevation of the magnetic pole center line exceeds the tolerance are reprocessed.

Images