Permanent magnet external drive deep sea submersible pump

Abstract

The permanent magnet external driving deep-sea submersible pump of the application constructs a cross-gap composite flow control structure between the impeller outlet and the guide vane inlet, the convex end of the auxiliary small vane extends into the groove ring, and the groove ring depth is greater than the radial groove, the small vane is parallel to the groove bottom surface and partially in the groove and partially outside the groove, so that the auxiliary small vane becomes a "bridging" element across the dynamic and static gap between the impeller and the water outlet section, the depth difference cooperation of the auxiliary small vane and the groove ring forms a local low impedance backflow inhibition zone, effectively blocks the excitation energy transmission path between the dynamic and static vane rows; the gradually expanding structure of the guide groove further promotes pressure recovery and vorticity dissipation. The multi-stage structure gradient cooperation makes the outlet flow field pressure pulsation main frequency amplitude significantly reduced, the hydraulic efficiency is stably improved due to the reduction of flow loss and excitation force attenuation, and is especially suitable for the long-term vibration reduction and efficiency improvement requirements under deep-sea working conditions.

Description

Technical Field

[0001] This invention relates to the field of fluid machinery technology, specifically to a deep-sea submersible pump, and more specifically to a permanent magnet externally driven deep-sea submersible pump. Background Technology

[0002] Deep-sea submersible pumps suffer from clogging, efficiency decline, and severe vibration, which are essentially due to pump body instability. Clogging is not simply the accumulation of foreign matter, but rather the formation of a progressive scale layer by fine particles on the blade pressure surface and volute. This layer alters the surface roughness and induces premature boundary layer transition, resulting in large-scale separation vortices in the mainstream region. These separation vortices consume effective energy and induce low-frequency pulsations, which, when coupled with the rotor's natural frequency, create a resonance tendency. Efficiency decline stems from the distortion of the velocity triangle caused by interstitial leakage flow and the deposit layer, resulting in a significant deviation of the actual head-flow curve from the design point. Furthermore, the compressibility of the high-pressure water in the deep sea causes a drift in specific speed, exacerbating the deviation. Vibration is not only excited by unbalanced forces but also amplified into transcritical flutter due to the nonlinear stiffness of the bearing supports under high pressure. These three factors, through a closed-loop feedback of flow field, structure, and interface wear, cause the system operating point to slide from the stability margin region to the unstable boundary, which is the fundamental internal logic of performance degradation.

[0003] Without improvements, the equipment will age irreversibly and rapidly during its operational cycle, widening the gap between its availability and rated lifespan year by year. This will ultimately force the project to terminate prematurely or incur the extremely high risk of replacement in ultra-deep water. Therefore, there is an urgent need to provide an improved deep-sea submersible pump structure.

[0004] This invention focuses on improving the blade and guide vane structure, as their hydraulic profile directly determines the particle migration trajectory and pressure pulsation generation mechanism. By optimizing the blade and guide vane structure, load distribution can be balanced, deposition paths can be blocked, and excitation frequencies can be reduced. This breaks the positive feedback loop of "deposition-erosion-vibration" and ensures long-term maintenance-free operation in the deep sea. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a permanent magnet externally driven deep-sea submersible pump.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A permanent magnet externally driven deep-sea submersible pump includes an inlet section, a motor stator, a motor rotor, an impeller, an outlet section, a shaft, and bearings. The inlet section, impeller, and outlet section are arranged sequentially along the fluid flow direction. One end of the shaft is fixedly mounted with the impeller via a key, and the other end is mounted with the outlet section via a bearing. The impeller includes an upper cover plate, inlet blades, and a lower cover plate. The motor rotor is fixedly mounted on the outside of the upper cover plate, and the motor stator is located radially outside the motor rotor, with its axial ends fixedly connected to the inlet section and the outlet section, respectively. The pump is characterized by: The intersection point a of the trailing edge of the inlet blade and the lower cover plate of the impeller is located at the outlet end of the lower cover plate of the impeller, and the intersection point b of the trailing edge of the inlet blade and the upper cover plate of the impeller is close to the bend of the upper cover plate of the impeller. The tail end of the upper cover plate of the impeller is provided with multiple radially grooved grooves evenly arranged circumferentially, and the radial grooves are located between the intersection point b and the tail end of the upper cover plate of the impeller. Auxiliary blades are provided in the radial grooves. One end of the auxiliary blade is located in the radial groove, and the other end protrudes from the radial groove and extends into the water outlet section. The auxiliary blades are straight blades, and the height of the auxiliary blades is less than the depth of the radial grooves.

[0008] Furthermore, the water outlet section includes an outer cover plate of the spatial guide vane, a spatial guide vane, and an inner cover plate of the spatial guide vane. The inner cover plate of the spatial guide vane is mounted on the bearing. The spatial guide vane is installed between the outer cover plate and the inner cover plate of the spatial guide vane. The intersection point c between the leading edge of the spatial guide vane and the inner cover plate of the spatial guide vane is located at the inlet of the inner cover plate of the spatial guide vane. The intersection point d between the leading edge of the spatial guide vane and the outer cover plate of the spatial guide vane is close to the bend of the outer cover plate of the spatial guide vane. A grooved ring and a flow guide groove are sequentially provided at the inlet of the outer cover plate of the guide vane.

[0009] Furthermore, the protruding end of the auxiliary leaflet extends into the grooved ring, and the depth of the grooved ring is greater than the depth of the radial groove.

[0010] Furthermore, the auxiliary leaflet is parallel to the bottom surface of the groove ring.

[0011] Furthermore, part of the auxiliary leaflet is located inside the groove ring, and part is located outside the groove ring.

[0012] Furthermore, the guide channel is a groove structure with multiple grooves evenly distributed along the circumferential inner wall of the outer cover plate of the spatial guide vane.

[0013] Furthermore, the depth of the guide groove is less than the depth of the groove ring.

[0014] Furthermore, the guide channel is a circular arc channel.

[0015] Furthermore, the width of the guide channel gradually increases along the direction of fluid flow.

[0016] Furthermore, the length of the auxiliary leaflet extending into the groove ring accounts for 20% to 30% of the total length of the auxiliary leaflet.

[0017] Furthermore, there is a gap between the inlet end of the auxiliary leaflet and the sidewall of the radial groove.

[0018] Furthermore, the height of the auxiliary leaflet is 50% to 80% of the depth of the radial groove.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. In this invention, the intersection point a of the trailing edge of the inlet blade and the lower cover plate of the impeller is located at the outlet end of the lower cover plate, and the intersection point b of the trailing edge of the inlet blade and the upper cover plate of the impeller is near the bend of the upper cover plate. The upper cover plate has multiple radially grooved sections evenly distributed circumferentially at its tail end, located between intersection point b and the tail end of the upper cover plate. Auxiliary blades are installed within these radial grooves; one end of each auxiliary blade is located within the radial groove, and the other end protrudes from the groove and extends into the outlet section. The auxiliary blades are straight blades, and their height is less than the depth of the radial grooves. This invention achieves vibration reduction and efficiency enhancement through impeller outlet structure optimization. The axial misalignment of the blade trailing edge and the intersection point of the upper and lower cover plates (the lower intersection point is located at the outlet end, and the upper intersection point is near the bend of the cover plate) improves velocity triangle matching and reduces impact loss. The radial groove at the tail end of the upper cover plate, housing a protruding auxiliary blade with a height less than the groove depth, dissipates high-frequency pressure pulsations, suppresses secondary flow and wake regions near the upper cover plate, and reduces mixing losses. Under the combined effect, the uniformity of the outlet flow field is improved, the hydraulic excitation is attenuated, the vibration intensity is reduced, and the hydraulic efficiency is reliably improved due to the reduction of flow losses.

[0021] 2. The water outlet section of this invention includes a spatial guide vane outer cover plate, a spatial guide vane, and a spatial guide vane inner cover plate. The spatial guide vane inner cover plate is mounted on a bearing. The spatial guide vane is installed between the spatial guide vane outer cover plate and the spatial guide vane inner cover plate. The intersection point c between the leading edge of the spatial guide vane and the spatial guide vane inner cover plate is located at the inlet of the spatial guide vane inner cover plate, and the intersection point d between the leading edge of the spatial guide vane and the spatial guide vane outer cover plate is near the bend of the spatial guide vane outer cover plate. A grooved ring and a flow guide groove are sequentially arranged at the inlet of the guide vane outer cover plate. The water outlet section of this invention achieves vibration reduction and efficiency enhancement through the synergistic effect of the spatial guide vane, the leading edge layout, and the flow guide structure. The axial misalignment of the intersection points of the leading edge of the spatial guide vane and the inner and outer cover plates, with the inner intersection point located at the inlet end and the outer intersection point near the bend of the outer cover plate, allows the guide vane inlet angle of attack to adaptively change along the blade height, effectively matching the non-uniform flow field at the impeller outlet and reducing impact loss and unsteady excitation force. A grooved ring and a guide channel are installed at the inlet of the guide vane outer cover plate. The grooved ring forms a local buffer cavity to homogenize the incoming flow pressure gradient, while the guide channel guides the fluid on the wall to turn in an orderly manner, suppressing corner separation and secondary vortex generation, and reducing low-frequency pulsation caused by flow separation. The dual structure works synergistically to improve the dynamic and static interference effect, significantly improving the uniformity of the outlet flow, reducing hydraulic losses, decreasing pump vibration intensity, and simultaneously improving operational stability and hydraulic efficiency.

[0022] 3. This invention further optimizes the specific structure, such as the protruding end of the auxiliary blade extending into the grooved ring, the depth of which is greater than the depth of the radial groove. The auxiliary blade is parallel to the bottom surface of the grooved ring. Part of the auxiliary blade is located inside the grooved ring, and part is located outside the grooved ring. The guide channel is a structure of multiple grooves evenly distributed along the circumferential inner wall of the outer cover plate of the spatial guide vane. The depth of the guide channel is less than the depth of the grooved ring. The guide channel is an arc groove. The width of the guide channel gradually increases along the fluid flow direction. The length of the auxiliary blade extending into the grooved ring accounts for 20% to 30% of the total length of the auxiliary blade. There is a gap between the inlet end of the auxiliary blade and the sidewall of the radial groove. The height of the auxiliary blade is 50% to 80% of the depth of the radial groove. This invention constructs a cross-gap composite flow control structure between the impeller outlet and the guide vane inlet. The core innovation lies in the fact that the protruding end of the auxiliary blade extends into the grooved ring, and the depth of the grooved ring is greater than that of the radial groove, with the blade parallel to the bottom surface of the groove, partly inside the groove and partly outside the groove. This design makes the auxiliary blade a "bridging" element that bridges the dynamic and static gap between the impeller and the outlet section. On the one hand, the protruding end extends into the groove ring to a depth of 20%–30% of the total blade length. Utilizing the deep cavity buffering effect of the groove ring, the secondary flow induced by the blade is guided into the groove ring for deceleration, pressurization, and energy dissipation, significantly reducing the high-frequency pressure pulsation caused by the interference between the impeller outlet wake and the guide vane leading edge. On the other hand, the blade height is 50%–80% of the radial groove depth, preserving sufficient flow space to avoid over-constraint. A gap is left between the inlet end and the sidewall of the radial groove to prevent flow blockage. Simultaneously, the guide channels are evenly distributed circumferentially along the outer cover plate of the spatial guide vane, employing a gradually changing depth and widening arc groove structure (depth less than the groove ring) to guide the wall fluid to turn in an orderly manner and homogenize the incoming flow. The depth difference between the auxiliary blade and the groove ring forms a local low-impedance backflow suppression zone, effectively blocking the excitation energy transfer path between the dynamic and static blade rows. The gradually expanding structure of the guide channels further promotes pressure recovery and vortex dissipation. The multi-stage structure and its sequential arrangement significantly reduce the amplitude of the dominant frequency of pressure pulsation in the outlet flow field. The hydraulic efficiency is steadily improved due to the reduction of flow loss and the attenuation of excitation force, making it particularly suitable for long-term vibration reduction and efficiency enhancement needs in deep-sea conditions. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of a deep-sea submersible pump with an external permanent magnet drive according to the present invention;

[0025] Figure 2 for Figure 1Enlarged structural diagram of region A in the middle;

[0026] Figure 3 This is a schematic diagram of the axial projection structure of the tail end portion of the impeller upper cover plate 41;

[0027] Figure 4 This is a schematic diagram of the axial projection structure of the inlet portion of the outer cover plate 51 of the space guide vane.

[0028] The reference numerals in the above figures are as follows: 1. Inlet section; 2. Motor stator; 3. Motor rotor; 4. Impeller; 5. Outlet section; 6. Shaft; 7. Bearing; 41. Upper cover plate; 42. Inlet blade; 43. Lower cover plate of impeller; 8. Radial groove; 9. Auxiliary blade; 51. Outer cover plate of spatial guide vane; 52. Spatial guide vane; 53. Inner cover plate of spatial guide vane; 10. Groove ring; 11. Guide groove. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] The present invention will now be described in further detail with reference to the accompanying drawings.

[0031] like Figure 1-4 As shown, a permanent magnet externally driven deep-sea submersible pump includes an inlet section 1, a motor stator 2, a motor rotor 3, an impeller 4, an outlet section 5, a shaft 6, and a bearing 7. The inlet section 1, impeller 4, and outlet section 5 are arranged sequentially along the fluid flow direction. One end of the shaft 6 is fixedly mounted with the impeller 4 via a key, and the other end is mounted with the outlet section 5 via the bearing 7. The impeller 4 includes an upper impeller cover plate 41, inlet blades 42, and a lower impeller cover plate 43. The motor rotor 3 is fixedly mounted on the outside of the upper impeller cover plate 41, and the motor stator 2 is located radially outside the motor rotor 3, with its axial ends fixedly connected to the inlet section 1 and the outlet section 5, respectively. Its distinguishing feature is... The intersection point a of the trailing edge of the inlet blade 42 and the impeller lower cover plate 43 is located at the outlet end of the impeller lower cover plate 43, and the intersection point b of the trailing edge of the inlet blade 42 and the impeller upper cover plate 41 is close to the bend of the impeller upper cover plate 41; the tail end of the impeller upper cover plate 41 is provided with a plurality of radially grooved grooves 8 evenly arranged in the circumferential direction, and the radial grooves 8 are located between the intersection point b and the tail end of the impeller upper cover plate 41; auxiliary blades 9 are provided in the radial grooves 8; one end of the auxiliary blade 9 is located in the radial groove 8, and the other end protrudes from the radial groove 8 and extends into the water outlet section 5; the auxiliary blade 9 is a straight plate-shaped blade, and the height of the auxiliary blade 9 is less than the depth of the radial groove 8.

[0032] Furthermore, the water outlet section 5 includes a spatial guide vane outer cover plate 51, a spatial guide vane 52, and a spatial guide vane inner cover plate 53. The spatial guide vane inner cover plate 53 is mounted on the bearing 7. The spatial guide vane 52 is mounted between the spatial guide vane outer cover plate 51 and the spatial guide vane inner cover plate 53. The intersection point c between the leading edge of the spatial guide vane 52 and the spatial guide vane inner cover plate 53 is located at the inlet of the spatial guide vane inner cover plate 53. The intersection point d between the leading edge of the spatial guide vane 52 and the spatial guide vane outer cover plate 51 is close to the bend of the spatial guide vane outer cover plate 51. A groove ring 10 and a guide groove 11 are sequentially provided at the inlet of the guide vane outer cover plate 51.

[0033] Furthermore, the protruding end of the auxiliary leaflet 9 extends into the groove ring 10, and the depth of the groove ring 10 is greater than the depth of the radial groove 8.

[0034] Furthermore, the auxiliary leaflet 9 is parallel to the bottom surface of the groove ring 10.

[0035] Furthermore, part of the auxiliary leaflet 9 is located inside the groove ring 10, and part is located outside the groove ring 10.

[0036] Furthermore, the guide groove 11 is a groove structure with multiple grooves evenly distributed along the circumferential inner wall of the outer cover plate 51 of the space guide vane.

[0037] Furthermore, the depth of the guide groove 11 is less than the depth of the groove ring 10.

[0038] Furthermore, the guide channel 11 is a circular arc groove.

[0039] Furthermore, the width of the guide channel 11 gradually increases along the direction of fluid flow.

[0040] Furthermore, the length of the auxiliary leaflet 9 extending into the groove ring 10 accounts for 20% to 30% of the total length of the auxiliary leaflet 9.

[0041] Furthermore, there is a gap between the inlet end of the auxiliary leaflet 9 and the sidewall of the radial groove 8.

[0042] Furthermore, the height of the auxiliary leaflet 9 is 50% to 80% of the depth of the radial groove 8.

[0043] In this invention, the intersection point 'a' of the trailing edge of the inlet blade and the lower cover plate of the impeller is located at the outlet end of the lower cover plate, and the intersection point 'b' of the trailing edge of the inlet blade and the upper cover plate of the impeller is near the bend of the upper cover plate. The upper cover plate has multiple radially evenly arranged grooves at its tail end, located between intersection point 'b' and the tail end of the upper cover plate. Auxiliary blades are arranged within these radial grooves; one end of each auxiliary blade is located within the radial groove, and the other end protrudes from the groove and extends into the outlet section. The auxiliary blades are straight blades, and their height is less than the depth of the radial grooves. This invention achieves vibration reduction and efficiency improvement through impeller outlet structure optimization. The axial misalignment of the blade trailing edge and the intersection point of the upper and lower cover plates (the lower intersection point is located at the outlet end, and the upper intersection point is near the bend of the cover plate) improves velocity triangle matching and reduces impact loss. The radial groove at the tail end of the upper cover plate, housing a protruding auxiliary blade with a height less than the groove depth, dissipates high-frequency pressure pulsations, suppresses secondary flow and wake regions near the upper cover plate, and reduces mixing losses. Under the combined effect, the uniformity of the outlet flow field is improved, the hydraulic excitation is attenuated, the vibration intensity is reduced, and the hydraulic efficiency is reliably improved due to the reduction of flow losses.

[0044] The water outlet section of this invention includes an outer cover plate of a spatial guide vane, a spatial guide vane, and an inner cover plate of a spatial guide vane. The inner cover plate is mounted on a bearing, and the spatial guide vane is installed between the outer and inner cover plates. The intersection point c between the leading edge of the spatial guide vane and the inner cover plate is located at the inlet of the inner cover plate, and the intersection point d between the leading edge of the spatial guide vane and the outer cover plate is near the bend of the outer cover plate. A grooved ring and a flow guide groove are sequentially arranged at the inlet of the outer cover plate. The water outlet section of this invention achieves vibration reduction and efficiency enhancement through the synergistic effect of the spatial guide vane, the leading edge layout, and the flow guidance structure. The axial misalignment of the intersection points of the leading edge of the spatial guide vane and the inner and outer cover plates, with the inner intersection point located at the inlet and the outer intersection point near the bend of the outer cover plate, allows the inlet angle of attack of the guide vane to adaptively change along the blade height, effectively matching the non-uniform flow field at the impeller outlet and reducing impact loss and unsteady excitation force. A grooved ring and a guide channel are installed at the inlet of the guide vane outer cover plate. The grooved ring forms a local buffer cavity to homogenize the incoming flow pressure gradient, while the guide channel guides the fluid on the wall to turn in an orderly manner, suppressing corner separation and secondary vortex generation, and reducing low-frequency pulsation caused by flow separation. The dual structure works synergistically to improve the dynamic and static interference effect, significantly improving the uniformity of the outlet flow, reducing hydraulic losses, decreasing pump vibration intensity, and simultaneously improving operational stability and hydraulic efficiency.

[0045] This invention further optimizes the specific structure, such as extending the protruding end of the auxiliary blade into the grooved ring, the depth of which is greater than the depth of the radial groove. The auxiliary blade is parallel to the bottom surface of the grooved ring. Part of the auxiliary blade is located inside the grooved ring, and part is located outside the grooved ring. The guide channel is a structure of multiple grooves evenly distributed along the circumferential inner wall of the outer cover plate of the spatial guide vane. The depth of the guide channel is less than the depth of the grooved ring. The guide channel is an arc groove. The width of the guide channel gradually increases along the fluid flow direction. The length of the auxiliary blade extending into the grooved ring accounts for 20% to 30% of the total length of the auxiliary blade. There is a gap between the inlet end of the auxiliary blade and the sidewall of the radial groove 8. The height of the auxiliary blade is 50% to 80% of the depth of the radial groove. This invention constructs a cross-gap composite flow control structure between the impeller outlet and the guide vane inlet. The core innovation lies in the fact that the protruding end of the auxiliary blade extends into the grooved ring, and the depth of the grooved ring is greater than that of the radial groove, with the blade parallel to the bottom surface of the groove, partly inside the groove and partly outside the groove. This design makes the auxiliary blade a "bridging" element that bridges the dynamic and static gap between the impeller and the outlet section. On the one hand, the protruding end extends into the groove ring to a depth of 20%–30% of the total blade length. Utilizing the deep cavity buffering effect of the groove ring, the secondary flow induced by the blade is guided into the groove ring for deceleration, pressurization, and energy dissipation, significantly reducing the high-frequency pressure pulsation caused by the interference between the impeller outlet wake and the guide vane leading edge. On the other hand, the blade height is 50%–80% of the radial groove depth, preserving sufficient flow space to avoid over-constraint. A gap is left between the inlet end and the sidewall of the radial groove to prevent flow blockage. Simultaneously, the guide channels are evenly distributed circumferentially along the outer cover plate of the spatial guide vane, employing a gradually changing depth and widening arc groove structure (depth less than the groove ring) to guide the wall fluid to turn in an orderly manner and homogenize the incoming flow. The depth difference between the auxiliary blade and the groove ring forms a local low-impedance backflow suppression zone, effectively blocking the excitation energy transfer path between the dynamic and static blade rows. The gradually expanding structure of the guide channels further promotes pressure recovery and vortex dissipation. The multi-stage structure and its sequential arrangement significantly reduce the amplitude of the dominant frequency of pressure pulsation in the outlet flow field. The hydraulic efficiency is steadily improved due to the reduction of flow loss and the attenuation of excitation force, making it particularly suitable for long-term vibration reduction and efficiency enhancement needs in deep-sea conditions.

[0046] The above embodiments are illustrative of the present invention and not intended to limit the invention. It is understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A permanent magnet externally driven deep-sea submersible pump, comprising an inlet section (1), a motor stator (2), a motor rotor (3), an impeller (4), an outlet section (5), a shaft (6), and a bearing (7); the inlet section (1), impeller (4), and outlet section (5) are arranged sequentially along the fluid flow direction; one end of the shaft (6) is fixedly mounted with the impeller (4) by a key, and the other end is mounted with the outlet section (5) by the bearing (7); the impeller (4) includes an upper impeller cover plate (41), inlet blades (42), and a lower impeller cover plate (43); the motor rotor (3) is fixedly mounted on the outside of the upper impeller cover plate (41), and the motor stator (2) is located radially outside the motor rotor (3) and its axial ends are fixedly connected to the inlet section (1) and the outlet section (5), respectively; characterized in that: The intersection point a of the trailing edge of the inlet blade (42) and the impeller lower cover plate (43) is located at the outlet end of the impeller lower cover plate (43), and the intersection point b of the trailing edge of the inlet blade (42) and the impeller upper cover plate (41) is close to the bend of the impeller upper cover plate (41). The tail end of the impeller upper cover plate (41) is provided with multiple radial grooves (8) evenly arranged along the circumference. The radial grooves (8) are located between the intersection point b and the tail end of the impeller upper cover plate (41). An auxiliary blade (9) is provided in the radial groove (8). One end of the auxiliary blade (9) is located in the radial groove (8), and the other end protrudes from the radial groove (8) and extends into the water outlet section (5). The auxiliary blade (9) is a straight blade, and the height of the auxiliary blade (9) is less than the depth of the radial groove (8).

2. The permanent magnet externally driven deep-sea submersible pump as described in claim 1, characterized in that, The water outlet section (5) includes a space guide vane outer cover plate (51), a space guide vane (52), and a space guide vane inner cover plate (53). The space guide vane inner cover plate (53) is mounted on a bearing (7). The space guide vane (52) is mounted between the space guide vane outer cover plate (51) and the space guide vane inner cover plate (53). The intersection point c between the leading edge of the space guide vane (52) and the space guide vane inner cover plate (53) is located at the inlet of the space guide vane inner cover plate (53). The intersection point d between the leading edge of the space guide vane (52) and the space guide vane outer cover plate (51) is close to the bend of the space guide vane outer cover plate (51). A groove ring (10) and a guide groove (11) are sequentially provided at the inlet of the guide vane outer cover plate (51).

3. The permanent magnet externally driven deep-sea submersible pump as described in claim 2, characterized in that, The protruding end of the auxiliary leaflet (9) extends into the groove ring (10), and the depth of the groove ring (10) is greater than the depth of the radial groove (8).

4. A permanent magnet externally driven deep-sea submersible pump as described in claim 3, characterized in that, The auxiliary leaflet (9) is parallel to the bottom surface of the groove ring (10).

5. A permanent magnet externally driven deep-sea submersible pump as described in claim 4, characterized in that, Part of the auxiliary leaflet (9) is located inside the grooved ring (10), and part is located outside the grooved ring (10).

6. A permanent magnet externally driven deep-sea submersible pump as described in claim 5, characterized in that, The guide groove (11) is a groove structure that is evenly distributed along the inner circumferential direction of the outer cover plate (51) of the space guide vane.

7. A permanent magnet externally driven deep-sea submersible pump as described in claim 6, characterized in that, The depth of the guide groove (11) is less than the depth of the groove ring (10).

8. A permanent magnet externally driven deep-sea submersible pump as described in claim 7, characterized in that, The guide groove (11) is a circular arc groove.

9. A permanent magnet externally driven deep-sea submersible pump as described in claim 8, characterized in that, The width of the guide channel (11) gradually increases along the direction of fluid flow.

10. A permanent magnet externally driven deep-sea submersible pump as described in claim 9, characterized in that, The length of the auxiliary leaflet (9) extending into the groove ring (10) accounts for 20% to 30% of the total length of the auxiliary leaflet (9).

11. A permanent magnet externally driven deep-sea submersible pump as described in claim 10, characterized in that, There is a gap between the inlet end of the auxiliary leaflet (9) and the sidewall of the radial groove (8).

12. A permanent magnet externally driven deep-sea submersible pump as described in claim 1, characterized in that, The height of the auxiliary leaflet (9) is 50% to 80% of the depth of the radial groove (8).

Images