Design method of oil injection port of motor stator core end

Abstract

This invention discloses a design method for oil injection ports at the ends of motor stator cores, comprising the following steps: S1: Designing the number of oil injection ports at each end of the stator core, with each port covering 3-5 slots of distributed windings; S2: Adjusting the average flow velocity of cooling oil at the injection ports, with the average flow velocity between 0.5 m / s and 3.0 m / s; S3: Creating a half-section model of the stator assembly; S4: Creating an envelope model of the winding ends; S5: Confirming the cooling oil landing point position; S6: Adjusting the cooling oil landing point position; S7: Verifying the cross-sectional area of ​​the injection port flow channel. This method features high speed and high reliability, making it highly suitable for the increasingly shorter product development cycles required today.

Description

Technical Field

[0001] This invention relates to the field of motor design technology, specifically to a design method for an oil injection port at the end of a motor stator core. Background Technology

[0002] Currently, oil cooling, which involves spraying oil through nozzles at the ends of the motor stator core to cool the stator windings, is a popular method. However, if the cross-section of the cooling oil channel formed by the nozzle is too large, the cooling oil cannot form a jet stream, and under gravity, it fails to cool the winding ends. If the cross-section is too small, although the cooling oil can form a jet stream, it results in significant flow resistance, increasing losses in the electric drive system and reducing system efficiency. Furthermore, if the coolant is positioned too close to the stator core end face, spraying only on the straight section of the winding end, the cooling effect is poor. Conversely, if the coolant is positioned too far from the stator core end face, it will not reach the winding ends, resulting in no cooling effect.

[0003] The existing approach involves first performing simulation analysis using simulation tools, followed by observation using a cooling test with a transparent shell to confirm the suitability of the cooling location and the magnitude of the oil flow resistance—a time-consuming and labor-intensive process. This invention proposes a design method for the oil injection port at the end of the motor stator core, which features high speed and high reliability, making it highly suitable for the increasingly shorter product development cycles required today. Summary of the Invention

[0004] The purpose of this invention is to provide a design method for the oil injection port at the end of the motor stator core, which has the significant advantages of high speed and high reliability, and is very suitable for the current demand for increasingly shorter product development cycles.

[0005] A design method for an oil injection port at the end of a motor stator core, provided by the present invention, includes the following steps: S1: Design the number of oil injection ports at each end of the stator core, with each oil injection port covering 3-5 slots of distributed windings; S2: Adjust the average flow rate of the cooling oil at the injection port to between 0.5 m / s and 3.0 m / s.

[0006] S3: Create a half-section model of the stator assembly; S4: Create the envelope model of the winding ends; S5: Confirm the location of the coolant drop point; S6: Adjust the coolant drop point; S7: Check the cross-sectional area of ​​the fuel injector channel.

[0007] Furthermore, in step S1 above, the oil injection port is located near the outer diameter of the stator core.

[0008] Furthermore, step S3 specifically includes: S31: In the model of a stator core with windings, create a reference surface based on two surfaces along the circumferential direction of the stator lamination, using an oil injection port in the stator core as an example. S32: Using the reference plane from step S31, remove half of the stator assembly model to obtain a half-section model.

[0009] Furthermore, step S4 specifically includes: S41: Using the reference plane from step S31, create a sketch; S42: Draw the motor axis, and create multiple first straight lines perpendicular to the motor axis at the intersection of the winding ends near the motor axis; S43: Simultaneously draw two envelope lines along the outer diameter of the winding end. The starting point of one envelope line intersects with two of the first lines, and the starting point of the other envelope line intersects with two other different first lines. S44: If the starting points of the two envelope lines are not parallel to the motor axis, then take the point closest to the motor axis among the starting points of the envelope lines as the starting point, draw an axial line parallel to the motor axis, and the starting point of the axial line intersects with two of the first lines. Measure the length of one of the envelope lines, and draw a first vertical line perpendicular to the motor axis at the 1 / 3 position of this envelope line near the end of the stator core. Measure the length of the axial line, and draw a second vertical line perpendicular to the motor axis at the 1 / 3 position of the axial line near the end of the stator core.

[0010] Furthermore, step S5 specifically includes: S51: Straight lines along the top and bottom surfaces of the stator core oil injection port in the radial direction of the motor; S52: Draw multiple second straight lines along the starting points of these straight lines based on the cooling oil flow path, with each pair of the second straight lines overlapping. S53: Draw multiple third straight lines along the ray direction of the second straight line closest to the end face of the stator core, with the endpoint of the third straight line falling on the axial straight line.

[0011] Furthermore, step S6 specifically includes: S61: Adjust the landing point of each end of the stator core to be on both sides of one of the first straight lines; S62: To meet the requirements of S61, adjust the position of the top and bottom surfaces of the stator core oil injection port along the radial direction of the motor.

[0012] The beneficial effects of this invention are that it has the significant characteristics of high speed and high reliability, which is very suitable for the current demand for increasingly shorter product development cycles. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a partial stator core model.

[0014] Figure 2 This is a schematic diagram of a partial stator core model. Detailed Implementation

[0015] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0016] This invention provides a design method for an oil injection port at the end of a motor stator core, comprising the following steps: S1: Design the number of oil injection ports at each end of the stator core, with each oil injection port covering 3-5 slots of distributed windings; S2: Adjust the average flow rate of the cooling oil at the injection port to between 0.5 m / s and 3.0 m / s.

[0017] S3: Create a half-section model of the stator assembly; S4: Create the envelope model of the winding ends; S5: Confirm the location of the coolant drop point; S6: Adjust the coolant drop point; S7: Check the cross-sectional area of ​​the fuel injector channel.

[0018] In step S1 above, the oil injection port is close to the outer diameter of the stator core.

[0019] Step S3 specifically includes: S31: In the model of a stator core with windings, create a reference surface based on two surfaces along the circumferential direction of the stator lamination, using an oil injection port in the stator core as an example. S32: Using the reference plane from step S31, remove half of the stator assembly model to obtain a half-section model.

[0020] Furthermore, step S4 specifically includes: S41: Using the reference plane from step S31, create a sketch; S42: Draw the motor axis, and create multiple first straight lines perpendicular to the motor axis at the intersection of the winding ends near the motor axis; S43: Simultaneously draw two envelope lines along the outer diameter of the winding end. The starting point of one envelope line intersects with two of the first lines, and the starting point of the other envelope line intersects with two other different first lines. S44: If the starting points of the two envelope lines are not parallel to the motor axis, then take the point closest to the motor axis among the starting points of the envelope lines as the starting point, draw an axial line parallel to the motor axis, and the starting point of the axial line intersects with two of the first lines. Measure the length of one of the envelope lines, and draw a first vertical line perpendicular to the motor axis at the 1 / 3 position of this envelope line near the end of the stator core. Measure the length of the axial line, and draw a second vertical line perpendicular to the motor axis at the 1 / 3 position of the axial line near the end of the stator core.

[0021] Step S5 specifically includes: S51: Straight lines along the top and bottom surfaces of the stator core oil injection port in the radial direction of the motor; S52: Draw multiple second straight lines along the starting points of these straight lines based on the cooling oil flow path, with each pair of the second straight lines overlapping. S53: Draw multiple third straight lines along the ray direction of the second straight line closest to the end face of the stator core, with the endpoint of the third straight line falling on the axial straight line.

[0022] Step S6 specifically includes: S61: Adjust the landing point of each end of the stator core to be on both sides of one of the first straight lines; S62: To meet the requirements of S61, adjust the position of the top and bottom surfaces of the stator core oil injection port along the radial direction of the motor.

[0023] Specifically, the stator assembly of a radial flux internal rotor motor will be used as an example for explanation, as follows: First, a model of the stator core with windings should be created. Then, the specific steps are as follows: S1: Design the number of oil injection ports at each end of the stator core, and the number of distributed windings covered by each oil injection port should preferably be 3-5 slots; The oil injection nozzles should be placed as close as possible to the outer diameter of the stator core to minimize adverse effects on electromagnetic performance. Count the total number of oil injection nozzles at both ends of the stator core.

[0024] S2: The average flow velocity of the fuel injector is designed to be between 0.5 m / s and 3.0 m / s; Extract the minimum cross-sectional area of ​​the cooling oil passage formed by the oil spray nozzle at the end of the stator core. Divide the rated cooling flow rate of the stator oil passage by the minimum cross-sectional area and then by the total number of oil spray nozzles to obtain the average flow velocity of the cooling oil at the oil spray nozzle. 0.5 m / s ≤ average flow velocity ≤ 3.0 m / s. Increasing the width of the fuel injector along the circumferential direction of the stator lamination increases the minimum cross-sectional area, thus reducing the average flow velocity; decreasing the width of the fuel injector along the circumferential direction of the stator lamination decreases the minimum cross-sectional area, thus increasing the average flow velocity.

[0025] S3: Create a half-section model of the stator assembly: Specifically, including: S31: In the model of a stator core with windings, create a reference surface based on two surfaces along the circumferential direction of the stator lamination, using an oil injection port in the stator core as an example. S32: Using this reference plane, remove half of the stator assembly model to obtain a half-section model.

[0026] S4: Create the envelope model of the winding ends.

[0027] Specifically, including: S41: Use the above reference plane to create a sketch; S42: Draw the motor axis. Create multiple first straight lines perpendicular to the motor axis at the intersection of the winding ends near the motor axis. Here, we take line 1, line 2, line 3, and line 4. S43: Simultaneously draw two envelope lines along the outer diameter of the winding end. Here, we take line 5 and line 6. The starting point of line 5 intersects with line 1 and line 2, and the starting point of line 6 intersects with line 3 and line 4.

[0028] Of course, in particular, if the starting point of line 5 or line 6 is not parallel to the motor axis, then the point closest to the motor axis among the starting points of line 5 or 6 is used as the starting point to draw line 7 parallel to the motor axis. The starting point of line 7 intersects with line 3 and line 4.

[0029] Measure the length of line 5, and draw line 8 perpendicular to the motor axis at the 1 / 3 position of line 5 near the end of the stator core. Measure the length of line 7, and draw line 9 perpendicular to the motor axis at the 1 / 3 position of line 7 near the end of the stator core.

[0030] In this example, line 5 is parallel to the motor axis.

[0031] S5: Confirm the location of the coolant drop.

[0032] Specifically, including: S51: Draw straight lines along the top and bottom surfaces of the motor radially from the stator core oil injection port; S52: Draw multiple second straight lines along the starting points of these straight lines based on the flow path of the cooling oil. The multiple second straight lines overlap in pairs. Here, we take straight lines 10, 11, 12, 13, and 14. Straight lines 10 and 11 overlap, and straight lines 12, 13, and 14 overlap. S53: Draw multiple third lines (line 15 and line 16) along the ray direction of the second straight line (line 11 and line 14) closest to the end face of the stator core. The endpoints of the third lines (point 1 and point 2) are on the axial line, which is line 7.

[0033] S6: Adjust the coolant drop point.

[0034] Specifically, including: S61: The landing point of each end of the stator core should be on both sides of straight line 8 or straight line 9. At least one end of the stator core should be on both sides of the first vertical straight line (take straight line 8) or the second vertical straight line (take straight line 9), and the landing point of the other end should be on the side of straight line 8 or straight line 9 closer to the end of the stator core. If the landing point does not meet the above requirements, the position of the top and bottom surfaces of the stator core oil injection port along the radial direction of the motor should be adjusted.

[0035] S7: Check the cross-sectional area of ​​the fuel injector channel.

[0036] Check the cross-sectional area of ​​the fuel injector channel according to step S2. If the cross-sectional area is not suitable, use step S2 to adjust the cross-sectional area of ​​the channel to a suitable value.

[0037] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A design method for an oil injection port at the end of a motor stator core, characterized in that, Including the following steps: S1: Design the number of oil injection ports at each end of the stator core, with each oil injection port covering 3-5 slots of distributed windings; S2: Adjust the average flow rate of the cooling oil at the injection port to between 0.5 m / s and 3.0 m / s. S3: Create a half-section model of the stator assembly; S4: Create the envelope model of the winding ends; S5: Confirm the location of the coolant drop point; S6: Adjust the coolant drop point; S7: Check the cross-sectional area of ​​the fuel injector channel.

2. The design method for the oil injection port at the end of the motor stator core according to claim 1, characterized in that, In step S1 above, the oil injection port is close to the outer diameter of the stator core.

3. The design method for the oil injection port at the end of the motor stator core according to claim 1, characterized in that, Step S3 specifically includes: S31: In the model of a stator core with windings, create a reference surface based on two surfaces along the circumferential direction of the stator lamination, using an oil injection port in the stator core as an example. S32: Using the reference plane from step S31, remove half of the stator assembly model to obtain a half-section model.

4. The design method for the oil injection port at the end of the motor stator core according to claim 3, characterized in that, Step S4 specifically includes: S41: Using the reference plane from step S31, create a sketch; S42: Draw the motor axis, and create multiple first straight lines perpendicular to the motor axis at the intersection of the winding ends near the motor axis; S43: Simultaneously draw two envelope lines along the outer diameter of the winding end. The starting point of one envelope line intersects with two of the first lines, and the starting point of the other envelope line intersects with two other different first lines. S44: If the starting points of the two envelope lines are not parallel to the motor axis, then take the point closest to the motor axis among the starting points of the envelope lines as the starting point, draw an axial line parallel to the motor axis, and the starting point of the axial line intersects with two of the first lines. Measure the length of one of the envelope lines, and draw a first vertical line perpendicular to the motor axis at the 1 / 3 position of this envelope line near the end of the stator core. Measure the length of the axial line, and draw a second vertical line perpendicular to the motor axis at the 1 / 3 position of the axial line near the end of the stator core.

5. The design method for the oil injection port at the end of the motor stator core according to claim 4, characterized in that, Step S5 specifically includes: S51: Straight lines along the top and bottom surfaces of the stator core oil injection port in the radial direction of the motor; S52: Draw multiple second straight lines along the starting points of these straight lines based on the cooling oil flow path, with each pair of the second straight lines overlapping. S53: Draw multiple third straight lines along the ray direction of the second straight line closest to the end face of the stator core, with the endpoint of the third straight line falling on the axial straight line.

6. The design method for the oil injection port at the end of the motor stator core according to claim 5, characterized in that, Step S6 specifically includes: S61: Adjust the landing point of each end of the stator core to be on both sides of one of the first straight lines; S62: If the requirement of S61 is to be met, adjust the position of the top and bottom surfaces of the stator core oil injection port along the radial direction of the motor.

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