Anti-play deep-well pump and variable-frequency proportional pressure control method thereof

Abstract

According to the anti-shifting deep-well pump, a centripetal stabilizing structure extending from the radial outer side to the radial inner side is arranged on the back face of a hub of an impeller, an anti-shifting small impeller is arranged in the center of the back face, and a centrifugal stabilizing structure extending from the radial inner side to the radial outer side is arranged on the front face of a hub of the anti-shifting small impeller; a multi-stage step face is arranged on the back face of a hub of the guide vane and comprises a step inner side face and a step outer side face, and a backflow structure is arranged on the step outer side face. The step inner side face comprises a first step inner side face connected with the pump shaft, the first step inner side face is of a center inwards-concave structure, and a flow throwing ring is arranged at the inwards-concave center. The hub back face of the anti-channeling small impeller comprises a first anti-channeling hub back face connected with the pump shaft, the first anti-channeling hub back face is of a structure with the center protruding outwards, and a flow throwing buffering groove matched with the flow throwing ring is formed in the center of the center protruding outwards. Due to the fact that the impeller and the guide vane structure are improved, movement is reduced, energy-saving and water-saving performance is optimized, and working condition performance and efficiency are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid machinery, in particular to a deep-well pump with anti-axial movement and a variable frequency proportional pressure control method thereof. BACKGROUND

[0002] Deep-well pumps are widely used in various industries and are the main energy-consuming equipment. With the practical needs of cost reduction and efficiency improvement, the energy-saving reconstruction of high-power deep-well pumps is increasingly required. The most effective way to save energy is to improve the efficiency of the pump. The stability design of the impeller and guide vane of the pump is directly related to the efficiency index of the pump. According to the experience of flow field analysis, using reasonable guide vane and impeller structure can greatly reduce the axial movement of the pump, and also optimize the energy-saving and water-saving performance and improve the efficiency. Therefore, it is necessary to optimize the design of the impeller and guide vane of the deep-well pump.

[0003] The prior art CN210397245U discloses a guide vane assembly of a deep-well pump, which comprises one or more guide vane groups 1. The guide vane group 1 comprises a guide vane shell 2, and the guide vane shell 2 is sequentially provided with a guide vane 3 and an impeller 4 from top to bottom. The upper end of the guide vane shell 2 is provided with a necked portion 5 which is inserted into a slot of the guide vane 3 to be fixed. The guide vane 3 is provided with a leak stop mechanism which can change the stress structure between parts and improve the stress area between stacked parts, thereby ensuring the reliability of compression.

[0004] However, the above-mentioned impeller and guide vane structure has design limitations, only involving the design of part of non-universal impeller and guide vane structure, and not essentially changing the related structure, which has poor adaptability, large axial movement, poor energy-saving and water-saving performance, and low efficiency. Therefore, in view of these problems, the present application proposes a deep-well pump with anti-axial movement and a variable frequency proportional pressure control method to solve the above-mentioned problems to reduce the axial movement and optimize the energy-saving and water-saving performance to improve the working condition performance and efficiency. SUMMARY

[0005] The present application aims to solve the problems existing in the prior art and proposes a deep-well pump with anti-axial movement and a variable frequency proportional pressure control method.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] The application discloses an anti-channeling deep well pump, which comprises a water inlet section, a pump shaft, an impeller, a guide vane, a water outlet section, and the impeller and the guide vane are arranged in a multi-stage series staggered mode; characterized in that: a hub back surface of the impeller is provided with a centripetal stabilizing structure extending from a radial outer side to a radial inner side, and a center of the hub back surface is provided with an anti-channeling small impeller, a hub front surface of the anti-channeling small impeller is provided with a centrifugal stabilizing structure extending from the radial inner side to the radial outer side; a hub back surface of the guide vane is provided with a multi-stage stepped surface, which comprises a stepped inner side surface and a stepped outer side surface, and the stepped outer side surface is provided with a backflow structure; wherein the centripetal stabilizing structure, the anti-channeling small impeller, the centrifugal stabilizing structure and the backflow structure form a microcirculation flow path to prevent axial channeling of the impeller and the guide vane; the stepped inner side surface comprises a first stepped inner side surface connected with the pump shaft, the first stepped inner side surface is in a central concave structure, and a flow throwing ring is arranged at a center of the concave structure; the hub back surface of the anti-channeling small impeller comprises a first anti-channeling hub back surface connected with the pump shaft, the first anti-channeling hub back surface is in a central convex structure, and a flow throwing buffer groove matched with the flow throwing ring is arranged at a center of the convex structure; and the stepped inner side surface and the hub back surface of the anti-channeling small impeller form a dynamic balance sealing structure.

[0008] Further, the anti-channeling small impeller is in a five-pointed star shape in section.

[0009] Further, the centripetal stabilizing structure is a flow channel in a curve structure, the curve structure is part of an Archimedes spiral, and an outlet of the flow channel is connected with a recess of the anti-channeling small impeller.

[0010] Further, the centrifugal stabilizing structure is a guide body in a rib structure, a center line of the rib structure is part of a hyperbola, and an inlet of the guide body is connected with the recess of the anti-channeling small impeller.

[0011] Further, the backflow structure is a linear groove uniformly distributed on a circumference, and an inlet of the linear groove is connected with an outlet of the anti-channeling small impeller.

[0012] Further, the stepped inner side surface further comprises a second stepped inner side surface, the second stepped inner side surface is a horizontal surface perpendicular to the axis, one side of the second stepped inner side surface is connected with the stepped outer side surface, and the other side of the second stepped inner side surface is connected with the first stepped inner side surface; the hub back surface of the anti-channeling small impeller further comprises a second anti-channeling hub back surface, one side of the second anti-channeling hub back surface is connected with the first anti-channeling hub back surface, and the second anti-channeling hub back surface is parallel to the second stepped inner side surface.

[0013] Further, the first stepped inner side surface comprises two first stepped inlet inner side surfaces and first stepped outlet inner side surfaces in an included angle, and the included angle is 80°-120°.

[0014] Further, the first anti-channeling hub back surface comprises two obtuse first anti-channeling hub inlet back surfaces and first anti-channeling hub outlet back surfaces, wherein the first anti-channeling hub inlet back surface is a converging flow surface with the first step inlet inner side surface in the flow direction, and the first anti-channeling hub outlet back surface is a diverging flow surface with the first step outlet inner side surface in the flow direction.

[0015] Further, the discharge flow channel is provided between the flow buffering groove and the hub front surface of the impeller, and the outlet direction of the discharge flow channel is tangent to the hub front surface of the impeller.

[0016] A variable frequency proportional pressure control method of a deep well pump, the deep well pump being an anti-channeling deep well pump, characterized in that the method comprises the following steps:

[0017] S1: system initialization, setting a basic target pressure P1 of the deep well pump, the pressure value being the minimum pressure meeting the basic water demand of the most unfavorable point of the pipe network;

[0018] S2: real-time monitoring and obtaining an instantaneous total flow Q of the pipe network system;

[0019] S3: based on the instantaneous total flow Q, dynamically calculating an additional pressure value ΔP according to a nonlinear pressure-flow proportional function relationship f(Q); wherein the function relationship f(Q) is configured such that when the instantaneous total flow Q is zero or very small, ΔP=0; when the instantaneous total flow Q increases, ΔP increases accordingly, but the growth rate gradually decreases with the increase of the instantaneous total flow Q;

[0020] S4: adding the basic target pressure P1 and the additional pressure value ΔP to obtain a dynamic target pressure P of the system at the current time;

[0021] S5: real-time acquisition of the actual pressure P2 of the pipe network;

[0022] S6: comparing the dynamic target pressure P and the actual pressure P2, generating a control signal and outputting it to the frequency converter through a PID control algorithm;

[0023] S7: the frequency converter adjusts the operating frequency of the deep well pump motor according to the control signal, thereby changing the rotational speed, so that the actual pressure P2 tracks the dynamic target pressure P, realizing constant pressure water supply according to demand, energy saving and water saving.

[0024] Further, the nonlinear pressure-flow proportional function relationship f(Q) is a piecewise function or a smooth curve function, and its mathematical expression is ΔP=K*(1-eˆ(-C))*Q or ΔP=K*Q*eˆ(-N); wherein K is a pressure proportional coefficient, C is a decay coefficient, N is a power index, 0

[0025] Further, the pressure proportionality coefficient K, the attenuation coefficient C, and the power exponent N are not fixed values, and they can be adaptively adjusted according to different time periods in a day or historical water use patterns.

[0026] Compared with the prior art, the application has the following advantages:

[0027] 1. The back surface of the hub of the impeller is provided with a centripetal stabilizing structure extending from the radial outer side to the radial inner side, and the center of the back surface is provided with an anti-channeling small impeller, and the front surface of the hub of the anti-channeling small impeller is provided with a centrifugal stabilizing structure extending from the radial inner side to the radial outer side; the back surface of the hub of the guide vane is provided with a multi-stage stepped surface, which includes a stepped inner side surface and a stepped outer side surface, and the stepped outer side surface is provided with a backflow structure, wherein the centripetal stabilizing structure, the anti-channeling small impeller, the centrifugal stabilizing structure, and the backflow structure form a micro-circulation flow path, effectively preventing axial movement of the impeller and the guide vane.

[0028] 2. The stepped inner side surface includes a first stepped inner side surface connected to the pump shaft, and the first stepped inner side surface is in a central concave structure, and a flow throwing ring is arranged at the center of the concave structure; the back surface of the hub of the anti-channeling small impeller includes a first anti-channeling hub back surface connected to the pump shaft, and the first anti-channeling hub back surface is in a central convex structure, and a flow throwing buffer groove matched with the flow throwing ring is arranged at the center of the convex structure, and the stepped inner side surface and the back surface of the hub of the anti-channeling small impeller effectively form a dynamic balance sealing structure.

[0029] 3. In view of efficient flow, it is crucial to optimize the circuit structure, and in the application, the anti-channeling small impeller adopts a five-point star shape, the centripetal stabilizing structure adopts an Archimedes spiral-shaped flow passage, the centrifugal stabilizing structure adopts a hyperbolic rib-shaped flow guide, and the backflow structure adopts a straight-line-shaped channel, which are optimized designs considering the working environment of the deep-well pump, greatly reducing channeling and optimizing energy-saving and water-saving performance, thereby improving working condition performance and efficiency.

[0030] 4. In order to optimize the balance effect, the applicant adopts the following ways: the second anti-channeling hub back surface is parallel to the second stepped inner side surface, the first anti-channeling hub inlet back surface and the first stepped inlet inner side surface are converging in the flow direction, the first anti-channeling hub outlet back surface and the first stepped outlet inner side surface are diverging in the flow direction, and the outlet direction of the discharge flow passage is tangent to the front surface of the hub of the impeller, which balances the impeller and the guide vane while reducing channeling.

[0031] 5. The dynamic target pressure P is compared with the actual pressure P2, and a control signal is generated and output to the frequency converter through a PID control algorithm; the frequency converter adjusts the operating frequency of the deep well pump motor according to the control signal, thereby changing the rotating speed, so that the actual pressure P2 tracks the dynamic target pressure P, and constant pressure water supply according to demand, energy saving and water saving is realized; compared with the prior art, the above-mentioned mode adopts variable frequency proportional pressure control, has higher automation degree, and can produce better energy saving and water saving effects. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is an axial sectional structure schematic diagram of the deep well pump in the prior art.

[0033] Figure 2 It is an improved structure schematic diagram of the impeller 3 and the guide vane 4 in the present application.

[0034] Figure 3 It is a relative relationship schematic diagram of the anti-channeling small impeller 6 and the centripetal stabilizing structure 7 in the present application.

[0035] Figure 4 It is a relative relationship schematic diagram of the anti-channeling small impeller 6 and the centrifugal stabilizing structure 8 in the present application.

[0036] Figure 5 It is an axial sectional structure schematic diagram of the backflow structure 9 in the present application.

[0037] In the figure: the water inlet section 1, the pump shaft 2, the impeller 3, the guide vane 4, the water outlet section 5, the centripetal stabilizing structure 7, the anti-channeling small impeller 6, the centrifugal stabilizing structure 8, the backflow structure 9, the inner side of the step 10, the outer side of the step 11, the back of the hub of the anti-channeling small impeller 6 12, the first inner side of the step 101, the flow throwing ring 102, the second inner side of the step 103, the first anti-channeling hub back 121, the flow throwing buffer groove 122, the second anti-channeling hub back 123, the discharge flow channel 124, the first step inlet inner side 1011, the first step outlet inner side 1012, the first anti-channeling hub inlet back 1211, the first anti-channeling hub outlet back 1212, and the arrows “→, ←, ↑, ↓” represent the liquid flow direction / flow state. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0039] The present application will be further described in detail below in combination with the drawings.

[0040] As Figures 1-5 shown, an anti-axial movement deep well pump comprises an inlet section 1, a pump shaft 2, an impeller 3, a guide vane 4, and an outlet section 5, wherein the impeller 3 and the guide vane 4 are arranged in a multi-stage series staggered manner; characterized in that: a hub back surface of the impeller 3 is provided with a centripetal stabilizing structure 7 extending from a radial outer side to a radial inner side, a back surface center is provided with an anti-axial movement small impeller 6, a hub front surface of the anti-axial movement small impeller 6 is provided with a centrifugal stabilizing structure 8 extending from a radial inner side to a radial outer side; a hub back surface of the guide vane 4 is provided with a multi-stage stepped surface, which comprises a stepped inner side surface 10 and a stepped outer side surface 11, and the stepped outer side surface 11 is provided with a backflow structure 9, wherein the centripetal stabilizing structure 7, the anti-axial movement small impeller 6, the centrifugal stabilizing structure 8, and the backflow structure 9 form a micro-circulation flow path to prevent axial movement of the impeller 3 and the guide vane 4; the stepped inner side surface 10 comprises a first stepped inner side surface 101 connected with the pump shaft 2, the first stepped inner side surface 101 is in a central concave structure, and a flow throwing ring 102 is arranged at a concave center; a hub back surface 12 of the anti-axial movement small impeller 6 comprises a first anti-axial movement hub back surface 121 connected with the pump shaft 2, the first anti-axial movement hub back surface 121 is in a central convex structure, and a flow throwing buffer groove 122 matched with the flow throwing ring 102 is arranged at a convex center, and the stepped inner side surface 10 and the hub back surface 12 of the anti-axial movement small impeller 6 form a dynamic balance sealing structure.

[0041] Further, a cross section of the anti-axial movement small impeller 6 is in a pentagram shape.

[0042] Further, the centripetal stabilizing structure 7 is a flow passage in a curve structure, the curve structure is part of an Archimedes spiral, and an outlet of the flow passage is communicated with a recess of the anti-axial movement small impeller 6.

[0043] Further, the centrifugal stabilizing structure 8 is a flow guide in a rib structure, a center line of the rib structure is part of a hyperbola, and an inlet of the flow guide is communicated with the recess of the anti-axial movement small impeller 6.

[0044] Further, the backflow structure 9 is a straight line type groove uniformly distributed on a circumference, an inlet of the straight line type groove is communicated with an outlet of the anti-axial movement small impeller 6.

[0045] Further, the stepped inner side surface 10 further comprises a second stepped inner side surface 103, the second stepped inner side surface 103 is a horizontal surface perpendicular to an axis, one side of the second stepped inner side surface 103 is connected with the stepped outer side surface 11, and the other side of the second stepped inner side surface 103 is connected with the first stepped inner side surface 101; the hub back surface 12 of the anti-axial movement small impeller 6 further comprises a second anti-axial movement hub back surface 123, one side of the second anti-axial movement hub back surface 123 is connected with the first anti-axial movement hub back surface 121, and the second anti-axial movement hub back surface 123 is parallel to the second stepped inner side surface 103.

[0046] Further, the first step inner side surface 101 comprises two first step inlet inner side surfaces 1011 and first step outlet inner side surfaces 1012 which are at an included angle of 80°-120°.

[0047] Further, the first anti-channeling hub back surface 121 comprises two first anti-channeling hub inlet back surfaces 1211 and first anti-channeling hub outlet back surfaces 1212 which are at an obtuse angle, wherein the first anti-channeling hub inlet back surface 1211 is a converging flow surface with the first step inlet inner side surface 1011 in the flow direction, and the first anti-channeling hub outlet back surface 1212 is a diverging flow surface with the first step outlet inner side surface 1012 in the flow direction.

[0048] Further, the flow discharge channel 124 is provided between the flow discharge channel 122 and the hub front surface of the impeller 3, and the outlet direction of the flow discharge channel 124 is tangent to the hub front surface of the impeller 3.

[0049] A variable frequency proportional pressure control method for a deep well pump, the deep well pump being an anti-channeling deep well pump, characterized in that it comprises the following steps:

[0050] S1: system initialization, setting the basic target pressure P1 of the deep well pump, which is the minimum pressure meeting the basic water demand of the most unfavorable point of the pipe network;

[0051] S2: real-time monitoring and obtaining the instantaneous total flow Q of the pipe network system;

[0052] S3: based on the instantaneous total flow Q, an additional pressure value ΔP is dynamically calculated according to a nonlinear pressure-flow proportional function relationship f(Q); wherein the function relationship f(Q) is configured as: when the instantaneous total flow Q is zero or very small, ΔP=0; when the instantaneous total flow Q increases, ΔP increases accordingly, but its growth rate gradually decreases with the increase of the instantaneous total flow Q;

[0053] S4: adding the basic target pressure P1 and the additional pressure value ΔP to obtain the dynamic target pressure P of the system at the current time;

[0054] S5: real-time acquisition of the actual pressure P2 of the pipe network;

[0055] S6: comparing the dynamic target pressure P and the actual pressure P2, generating a control signal through a PID control algorithm and outputting it to the frequency converter;

[0056] S7: the frequency converter adjusts the operating frequency of the deep well pump motor according to the control signal, thereby changing its speed, so that the actual pressure P2 tracks the dynamic target pressure P, realizing on-demand, energy-saving and water-saving constant pressure water supply.

[0057] Further, the non-linear pressure-flow ratio function f(Q) is a piecewise function or a smooth curve function, and its mathematical expression is ΔP=K*(1-eˆ(-C))*Q or ΔP=K*Q*eˆ(-N); wherein K is a pressure ratio coefficient, C is a decay coefficient, N is a power index, 0

[0058] Further, the pressure ratio coefficient K, the decay coefficient C, and the power index N are not fixed values, and they can be adaptively adjusted according to different time periods in a day or historical water usage patterns.

[0059] The hub back surface of the impeller is provided with a centripetal stabilizing structure extending from the radial outside to the radial inside, and the center of the back surface is provided with an anti-channeling small impeller, and the hub front surface of the anti-channeling small impeller is provided with a centrifugal stabilizing structure extending from the radial inside to the radial outside; the hub back surface of the guide vane is provided with a multi-stage stepped surface, which includes a stepped inside surface and a stepped outside surface, and the stepped outside surface is provided with a backflow structure, wherein the centripetal stabilizing structure, the anti-channeling small impeller, the centrifugal stabilizing structure, and the backflow structure form a micro-circulation flow path, effectively preventing the axial movement of the impeller and the guide vane.

[0060] The stepped inside surface includes a first stepped inside surface connected to the pump shaft, and the first stepped inside surface has a central concave structure, and the concave center is provided with a flow throwing ring; the hub back surface of the anti-channeling small impeller includes a first anti-channeling hub back surface connected to the pump shaft, and the first anti-channeling hub back surface has a central convex structure, and the convex center is provided with a flow throwing buffer groove matched with the flow throwing ring, and the stepped inside surface and the hub back surface of the anti-channeling small impeller effectively form a dynamic balance sealing structure.

[0061] In view of efficient flow, it is crucial to optimize the circuit structure. In the present application, the anti-channeling small impeller adopts a five-point star shape, the centripetal stabilizing structure adopts an Archimedes spiral-shaped flow passage, the centrifugal stabilizing structure adopts a hyperbolic rib-shaped flow guide, and the backflow structure adopts a straight-line groove. These structures are optimized designs considering the working environment of the deep-well pump, greatly reducing the channeling and optimizing the energy-saving and water-saving performance, thereby improving the working condition performance and efficiency.

[0062] In order to optimize the balance effect, the applicant adopts the following methods: the second anti-channeling hub back surface is parallel to the second stepped inside surface, the first anti-channeling hub inlet back surface and the first stepped inlet inside surface have a converging flow surface in the flow direction, the first anti-channeling hub outlet back surface and the first stepped outlet inside surface have a diverging flow surface in the flow direction, and the outlet direction of the discharge flow passage is tangent to the hub front surface of the impeller. These methods balance the impeller and the guide vane while reducing the channeling.

[0063] The dynamic target pressure P is compared with the actual pressure P2, a control signal is generated by a PID control algorithm and is output to the frequency converter, the frequency converter adjusts the running frequency of the motor of the deep-well pump according to the control signal, so as to change the rotating speed, so that the actual pressure P2 tracks the dynamic target pressure P, and constant pressure water supply according to demand, energy saving and water saving is realized.

[0064] The above embodiments are illustrative of the present application, but are not a limitation of the present application, and it can be understood that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and the protection scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A deep well pump with anti-slip mechanism, comprising an inlet section (1), a pump shaft (2), an impeller (3), guide vanes (4), and an outlet section (5), wherein the impeller (3) and guide vanes (4) are arranged in a multi-stage series staggered configuration; characterized in that: The impeller (3) has a centripetal stabilizing structure (7) extending radially outward to radially inward on the back of its hub, and an anti-cavitation impeller (6) is provided at the center of its back. The anti-cavitation impeller (6) has a centrifugal stabilizing structure (8) extending radially inward to radially outward on the front of its hub. The guide vane (4) has a multi-stage stepped surface on its back of its hub, including an inner stepped surface (10) and an outer stepped surface (11). A reflux structure (9) is provided on the outer stepped surface (11). The centripetal stabilizing structure (7), the anti-cavitation impeller (6), the centrifugal stabilizing structure (8), and the reflux structure (9) form a micro-circulation flow path to prevent the impeller (3) and guide vane (4) from cavitating. The axial movement of the step inner side (10) includes a first step inner side (101) connected to the pump shaft (2), the first step inner side (101) has a central concave structure, and a flow-throwing ring (102) is provided at the concave center; the hub back (12) of the anti-cavitation impeller (6) includes a first anti-cavitation hub back (121) connected to the pump shaft (2), the first anti-cavitation hub back (121) has a central convex structure, and a flow-throwing buffer groove (122) that cooperates with the flow-throwing ring (102) is provided at the convex center. The step inner side (10) and the hub back (12) of the anti-cavitation impeller (6) constitute a dynamic balance sealing structure.

2. The anti-slip deep well pump as described in claim 1, characterized in that, The cross-section of the anti-slip impeller (6) is in the shape of a five-pointed star.

3. The anti-slip deep well pump as described in claim 2, characterized in that, The centripetal stabilizing structure (7) is a curved flow channel, which is part of the Archimedean spiral. The outlet of the flow channel is connected to the recess of the anti-channel impeller (6).

4. The anti-slip deep well pump as described in claim 2, characterized in that, The centrifugal stabilizing structure (8) is a ribbed fluid guide, the center line of which is part of a hyperbola, and the inlet of the fluid guide is connected to the recess of the anti-channel impeller (6).

5. The anti-slip deep well pump as described in claim 2, characterized in that, The reflux structure (9) is a straight channel evenly distributed around the circumference, and its inlet is connected to the outlet of the anti-channel impeller (6).

6. The anti-slip deep well pump as described in claim 1, characterized in that, The inner side of the step (10) also includes a second inner side of the step (103), which is a horizontal plane perpendicular to the axis. One side of the second inner side of the step (103) is connected to the outer side of the step (11), and the other side is connected to the inner side of the first step (101). The back of the hub of the anti-slip impeller (6) (12) also includes a second anti-slip hub back (123), which is connected to the back of the first anti-slip hub (121) on one side. The back of the second anti-slip hub (123) is parallel to the inner side of the second step (103).

7. The anti-slip deep well pump as described in claim 1, characterized in that, The inner side of the first step (101) includes two inner sides of the first step inlet (1011) and the inner side of the first step outlet (1012) at an angle of 80° to 120°.

8. The anti-slip deep well pump as described in claim 7, characterized in that, The back side of the first anti-slip hub (121) includes two obtuse-angled back sides of the first anti-slip hub inlet (1211) and the back side of the first anti-slip hub outlet (1212), wherein the back side of the first anti-slip hub inlet (1211) and the inner side of the first step inlet (1011) form a narrowing flow surface in the flow direction, and the back side of the first anti-slip hub outlet (1212) and the inner side of the first step outlet (1012) form a gradually expanding flow surface in the flow direction.

9. The anti-slip deep well pump as described in claim 1, characterized in that, A discharge channel (124) is provided between the flow buffer trough (122) and the front of the impeller (3) hub, and the outlet direction of the discharge channel (124) is tangent to the front of the impeller (3) hub.

10. A variable frequency proportional pressure control method for a deep well pump, wherein the deep well pump is an anti-slip deep well pump as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1: System initialization, setting the basic target pressure P1 of the deep well pump. This pressure value is the minimum pressure required to meet the basic water demand at the most unfavorable point of the pipeline network. S2: Real-time monitoring and acquisition of the instantaneous total flow rate Q of the pipeline network system; S3: Based on the instantaneous total flow rate Q, an additional pressure value ΔP is dynamically calculated according to a nonlinear pressure-flow ratio function relationship f(Q); The functional relationship f(Q) is configured as follows: when the instantaneous total flow rate Q is zero or extremely small, ΔP = 0; as the instantaneous total flow rate Q increases, ΔP increases accordingly, but its growth rate gradually decreases as the instantaneous total flow rate Q increases. S4: Add the basic target pressure P1 to the additional pressure value ΔP to obtain the dynamic target pressure P of the system at the current moment; S5: Real-time acquisition of the actual pressure P2 of the pipeline network; S6: Compare the dynamic target pressure P with the actual pressure P2, generate a control signal through the PID control algorithm, and output it to the frequency converter; S7: The frequency converter adjusts the operating frequency of the deep well pump motor according to the control signal, thereby changing its speed so that the actual pressure P2 tracks the dynamic target pressure P, realizing constant pressure water supply that is on demand, energy-saving, and water-saving.

11. The variable frequency proportional pressure control method for a deep well pump as described in claim 10, characterized in that, The nonlinear pressure-flow ratio function f(Q) is a piecewise function or a smooth curve function, and its mathematical expression is ΔP=K*(1-eˆ(-C))*Q or ΔP=K*Q*eˆ(-N); where K is the pressure ratio coefficient, C is the attenuation coefficient, N is the power exponent, 0<N<1, and e is the natural constant. These coefficients are obtained through pump characteristic curves and hydraulic model tests of the pipeline network.

12. The variable frequency proportional pressure control method for a deep well pump as described in claim 11, characterized in that, The pressure proportionality coefficient K, attenuation coefficient C, and power exponent N are not fixed values; they can be adaptively adjusted according to different times of day or historical water usage patterns.

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