Magnetic suspension device capable of improving control capability, motor and pump

Abstract

The utility model relates to a magnetic suspension device, motor and pump for increasing control ability, including: enhancement winding, permanent magnet rotor, main shaft and stator assembly, two permanent magnet rotor are coaxial and are arranged along up and down direction, two permanent magnet rotor are respectively and fixedly connected with main shaft, two permanent magnet rotor have the same magnetic pole number and magnetic pole arrangement direction, and the stator assembly has the same magnetic pole number and the same magnetic pole arrangement direction. The two stator assemblies are respectively located at the outer sides of the two permanent magnet rotors, the two stator assemblies respectively drive the two permanent magnet rotors to suspend and rotate through magnetic force, the enhanced winding comprises a plurality of enhanced coils, and the enhanced coils of the two enhanced windings are respectively and uniformly distributed around the two permanent magnet rotors. The outer sides of the upper permanent magnet rotor and the lower permanent magnet rotor are both provided with the reinforcing windings, and when the main shaft moves axially, the reinforcing windings provide extra magnetic pulling force for the main shaft, so that the main shaft is reset, and the axial deviation of the main shaft is reduced; the upper and lower enhanced windings respectively generate different enhanced magnetic circuits, and axial magnetic pull forces with different sizes can be provided for the upper and lower permanent magnet rotors.

Description

TECHNICAL FIELD

[0001] The utility model relates to magnetic suspension device technical field especially a kind of magnetic suspension device of increasing control ability, motor and pump. BACKGROUND

[0002] Traditional centrifugal pump usually uses mechanical bearing to support and position rotor, and this design is prone to problems such as bearing wear, lubricant failure, unreliable sealing and inability to meet ultra-clean requirements. In addition, traditional pumps have vibration and noise problems and high operating costs. In order to overcome these shortcomings, magnetic suspension technology is widely used in the field of pumps.

[0003] Magnetic suspension technology suspends the impeller in the pump shell by using magnetic field, thereby achieving a contactless and wear-free operating state. Compared with traditional mechanical bearing centrifugal pumps, magnetic suspension pumps have higher efficiency, longer service life and lower maintenance cost.

[0004] Although significant progress has been made in magnetic suspension pumps, there are still some challenges in existing technology. In particular, thin-sheet magnetic suspension motors have poor control of main shaft axial movement, and the main shaft is prone to excessive deviation, which affects normal use. SUMMARY

[0005] The utility model aims at solving above-mentioned problem, provides a kind of magnetic suspension device of increasing control ability, motor and pump, solves above-mentioned technical problem.

[0006] A kind of magnetic suspension device of increasing control ability, including: enhanced winding, permanent magnet rotor, main shaft and stator assembly, two permanent magnet rotors are coaxial and are arranged along the up and down direction, two permanent magnet rotors are fixedly connected with main shaft respectively, the magnetic pole number of two permanent magnet rotors is same and the magnetic pole arrangement direction is same, two stator assemblies are located respectively outside two permanent magnet rotors, two stator assemblies are respectively driven two permanent magnet rotors to suspend and rotate by magnetic force, the enhanced winding includes multiple enhancement coils, the enhancement coil of two enhanced windings is respectively arranged uniformly around two permanent magnet rotors.

[0007] Further, the stator assembly includes a first magnetic yoke and a coil set, the coil set is fixedly wrapped outside the first magnetic yoke, the first magnetic yoke and the coil set are uniformly arranged around the permanent magnet rotor, and the enhancement coil is fixedly connected with the first magnetic yoke.

[0008] Further, the stator assembly further includes a second magnetic yoke, the first magnetic yoke and the second magnetic yoke are shared by two stator assemblies, the second magnetic yoke is located between the coil sets of two stator assemblies and between the two enhancement coils, the second magnetic yoke is annular, the main shaft passes through the through hole in the middle of the second magnetic yoke, and the first magnetic yoke passes through the second magnetic yoke in the up and down direction.

[0009] Further, the first magnetic yoke comprises an axial arm and a first radial arm, the axial arm is fixedly connected with the first radial arm at both ends, the first radial arm protrudes inward and is located at the radial outer side of the permanent magnet rotor, the coil group is sleeved on the outer side of the axial arm, and the reinforcing coil corresponds to the first radial arm one by one.

[0010] Further, the first magnetic yoke further comprises a second radial arm, the second radial arm is in contact with and fixedly connected with the axial arm, and the reinforcing coil is sleeved on the outer side of the second radial arm.

[0011] Further, the axis of the reinforcing coil is perpendicular to the axis of the coil group.

[0012] Further, when the reinforcing coil is located at the axial outer side of the two first radial arms, the axial arm is formed with an end portion, and an axial extension arm is formed on the end portion, and the axial extension arm is located at the radial outer side of the reinforcing coil.

[0013] Further, the main shaft is made of a non-magnetic conductive material.

[0014] A motor using the magnetic suspension device: further comprising a housing, the stator assembly is fixedly connected with the housing, and the permanent magnet rotor and the main shaft are not in contact with the housing.

[0015] A pump using the motor: further comprising a pump housing and an impeller, the pump housing is fixed with the housing and is inserted into the inside of the housing, the pump housing is formed with an inlet and an outlet respectively, the permanent magnet rotor and the main shaft are located in the inside of the pump housing, and the impeller is fixedly connected with the permanent magnet rotor and / or the main shaft.

[0016] The utility model has the advantages that:

[0017] 1. The upper and lower permanent magnet rotors are provided with reinforcing windings on the outer sides, when the main shaft moves in the axial direction, the reinforcing windings provide the main shaft with additional magnetic pulling force, so that the main shaft is reset, and the axial deviation of the main shaft is reduced;

[0018] 2. When the main shaft does not produce axial deviation, the upper and lower reinforcing windings can be selected to be energized, because the magnetic field generated by the reinforcing coil and the rotating coil is the same, so the rotating driving force on the permanent magnet rotor is increased;

[0019] 3. When the main shaft does not produce axial deviation and the radial main control force is insufficient, the reinforcing windings can also adopt the same control strategy as the suspension coil to generate the same magnetic field as the suspension coil, so as to enhance the radial control force on the permanent magnet rotor;

[0020] 4. Two stator assemblies correspond to one permanent magnet rotor respectively, two independent magnetic circuits are formed, the total electromagnetic force suffered by the permanent magnet rotor is improved, so that greater power is provided for the main shaft under the condition of same motor size, and the flow and head of the pump are improved.

[0021] 5. The two independent magnetic circuits can change the magnetic force suffered by the two permanent magnet rotors respectively, so that two different forces are provided for the two ends of the main shaft when the main shaft suffers radial external force near the impeller end, the deviation and deflection amplitude of the main shaft are reduced, and the stability of the main shaft during rotation is improved. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only one embodiment of the present application, and for those skilled in the art, other drawings can be obtained on the basis of the provided drawings without creative labor.

[0023] Figure 1 : schematic diagram of magnetic pole change of rotating magnetic field;

[0024] Figure 2 : schematic diagram of magnetic pole change of coil of levitation magnetic field;

[0025] Figure 3 : main view of sectional view of magnetic suspension device;

[0026] Figure 4 : main view of sectional view of magnetic suspension device;

[0027] Figure 5 : main view of sectional view of magnetic suspension pump;

[0028] Figure 6 : schematic diagram of sectional structure at A-A in Figure 5

[0029] Figure 7 : perspective view of magnetic suspension pump. DETAILED DESCRIPTION

[0030] The present application will be further described below in combination with the drawings and examples:

[0031] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0032] ​In the description of the utility model, it needs to be explained that, unless there is definite stipulation and limitation, the terms "mount", "connect", "connect" should be understood in broad sense, for example, it can be fixed connection, also can be detachable connection, or integrally connected, it can be direct connection, also can be indirectly connected through intermediate medium.

[0033] In the description of the utility model, it needs to be understood that, the orientation or position relation indicated by the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or position relation shown in the drawing, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the utility model.

[0034] Embodiment one:

[0035] As Figures 1 to 7 Indicated, a kind of magnetic suspension device of increasing control ability, comprising: reinforcing winding, permanent magnet rotor 5, main shaft 6 and stator assembly, two permanent magnet rotors 5 are coaxial and are arranged along up-down direction, two permanent magnet rotors 5 are respectively fixedly connected with main shaft 6, the magnetic pole number of two permanent magnet rotors 5 is same and the magnetic pole arrangement direction is same, two stator assemblies are respectively located two permanent magnet rotors 5 outer side, two stator assemblies are respectively driven two permanent magnet rotors 5 suspension and rotation by magnetic force, the reinforcing winding includes multiple reinforcing coils 4, the reinforcing coil 4 of two reinforcing windings is respectively arranged uniformly around two permanent magnet rotors 5, and each reinforcing winding provides axial magnetic force to corresponding permanent magnet rotor 5.

[0036] Further, the stator assembly includes first magnetic yoke 1 and coil group, the coil group is sleeved and fixed on the outer side of first magnetic yoke 1, the first magnetic yoke 1 and coil group are arranged uniformly around permanent magnet rotor 5, and the reinforcing coil 4 is fixedly connected with first magnetic yoke 1.

[0037] Further, the stator assembly further includes second magnetic yoke 9, two stator assemblies share first magnetic yoke 1 and second magnetic yoke 9, the second magnetic yoke 9 is located between the coil group of two stator assemblies and between two reinforcing coils 4, the second magnetic yoke 9 is annular, the main shaft 6 passes through the through hole in the middle of second magnetic yoke 9, and the first magnetic yoke 1 passes through second magnetic yoke 9 in up-down direction.

[0038] Furthermore, it also includes a radial sensor and a controller. The radial sensor is used to detect the radial position of the upper and lower ends of the main shaft 6, and the controller is used to change the current of the suspension coil 2 in the coil group. By changing the magnitude of the current in the upper and lower suspension coils 2, different magnetic forces are applied to the two permanent magnet rotors 5, causing the main shaft 6 to deflect.

[0039] Taking an example where each stator assembly has 8 coil groups and each permanent magnet rotor 5 has two radially magnetized magnetic poles, the levitation and rotation principle of two permanent magnet rotors 5 corresponding to an independent magnetic circuit is explained. It should be noted that the structure of the two permanent magnet rotors 5 corresponding to one magnetic circuit in this embodiment is not only applicable to the aforementioned eight first magnetic yokes 1 and two magnetic poles of the permanent magnet rotor 5, but also applicable to various combinations of permanent magnet rotors 5 with different numbers of magnetic poles and different numbers of coil groups.

[0040] Each coil group may include one or more coils:

[0041] Optionally, a coil group includes a single coil. In this case, a single coil provides both the rotating magnetic field and the levitation magnetic field to a permanent magnet rotor 5. The structure using only a single coil is simpler, but it places higher demands on the control system.

[0042] Optionally, the coil group includes a levitation coil 2 and a rotating coil 3, which are respectively mounted on the outside of the first magnetic yoke 1. The rotating coil 3 is used to drive the permanent magnet rotor 5 to rotate. The levitation coil 2 and the rotating coil 3 together drive the permanent magnet rotor 5 to levitate. The rotating coil 3 in the same coil group is located at the end of the levitation coil 2 near the second magnetic yoke 9. This method uses more coils in each coil group, but the requirements for the control system are lower.

[0043] It should be noted that the existing technology for magnetic levitation bearingless motors is to drive permanent magnets to levitate and rotate via coil groups.

[0044] It should be noted that, as Figure 4 As shown, Figure 4 When both the upper and lower reinforcing coils 4 are energized, the reinforcing windings provide a strong rotational driving force. For example... Figure 3 As shown, during axial offset control, only one set of reinforcing coils 4 in the upper and lower sets of reinforcing windings is energized and has a magnetic circuit passing through it. The magnetic circuit needs to be closed within the second yoke 9.

[0045] Furthermore, the first magnetic yoke 1 includes an axial arm 10 and a first radial arm 11. The two ends of the axial arm 10 are fixedly connected to the first radial arm 11, and the first radial arm 11 protrudes inward and is located on the radial outer side of the permanent magnet rotor 5. The coil assembly is fitted on the outer side of the axial arm 10. The reinforcing coil 4 corresponds one-to-one with the first radial arm 11. The reinforcing coil 4 is located on the upper side and / or lower side of the first radial arm 11 corresponding to it.

[0046] like Figure 3 As shown, the upper coil group generates magnetomotive force, and the upper magnetic circuit passes through the upper half of the left first magnetic yoke 1, the upper permanent magnet rotor 5, the upper half of the right first magnetic yoke 1 and the second magnetic yoke 9 respectively; the lower coil group generates magnetomotive force, and the lower magnetic circuit passes through the lower half of the left first magnetic yoke 1, the lower permanent magnet rotor 5, the lower half of the right first magnetic yoke 1 and the second magnetic yoke 9 respectively.

[0047] It should be noted that each independent main magnetic circuit 14 ( Figure 3 (with arrows in the middle) includes the superposition of two components: the rotating magnetic circuit generated by the rotating coil 3 and the levitation magnetic circuit generated by the levitation coil 2.

[0048] Now, let the rotating coils 3 of two adjacent first magnetic yokes 1 be energized with currents in the same direction, generating an N-pole magnetic field at a certain moment. Then, the rotating coils 3 of the two radially symmetrical first magnetic yokes 1 (on the same stator assembly) should be energized with currents in opposite directions, thereby generating an S-pole magnetic field at the same moment. At this time, a pair of magnetic fields required for rotation are formed. Through the phase change of the current, the pair of magnetic fields are rotated, thereby driving the permanent magnet rotor 5 to rotate. The changes in the rotating magnetic field and the position of the permanent magnet rotor 5 are as follows: Figure 1 As shown.

[0049] in, Figure 1 The upper and lower layers are viewed from above. Figure 1 In this context, "upper layer" refers to the magnetic field of the upper stator assembly and the upper permanent magnet rotor 5, "lower layer" refers to the magnetic field of the lower stator assembly and the lower permanent magnet rotor 5, "lower angle" refers to the rotation angle of the permanent magnet rotor 5, the magnetic field inside the circle is the magnetic field of the permanent magnet rotor 5, and the magnetic field outside the circle is the rotating magnetic field of the corresponding first radial arm 11.

[0050] Radial active levitation of the permanent magnet rotor 5 requires the generation of two pairs of magnetic poles by energizing the levitation coil 2 of the stator assembly, which is existing technology in the field of magnetic levitation motors. The number of levitation magnetic pole pairs is equal to the number of rotating magnetic pole pairs ± 1 pair. The offset correction of the permanent magnet rotor 5 is achieved by superimposing the levitation magnetic field onto the resultant magnetic field of the rotating magnetic field.

[0051] The positional changes of the levitation magnetic field and the permanent magnet rotor 5 are as follows: Figure 2 As shown. Among them, Figure 2The upper layer and the lower layer in the figure are the top view perspective, Figure 2 The "upper layer" in the figure refers to the magnetic field of the upper layer stator assembly and the upper layer permanent magnet rotor 5, the "lower layer" refers to the magnetic field of the lower layer stator assembly and the lower layer permanent magnet rotor 5, the angle below refers to the angle of rotation of the permanent magnet rotor 5, the magnetic field inside the circle is the magnetic field of the permanent magnet rotor 5, and the magnetic field outside the circle is the suspension magnetic field of the corresponding stator assembly.

[0052] Among them, in addition to the radial 2 degrees of freedom being active suspension and axial rotation, the remaining degrees of freedom are passive suspension.

[0053] It should be noted that since the polarities of the axial magnetic poles of the two permanent magnet rotors 5 are the same, the polarities of the two first radial arms 11 of the same first magnetic yoke 1 are the same.

[0054] Further, the axis of the enhancement coil 4 is perpendicular to the axis of the coil group.

[0055] The positions of the two enhancement windings have the following ways:

[0056] Way one: the enhancement coils 4 of the two enhancement windings are respectively located on the upper side of the corresponding first radial arm 11.

[0057] When the main shaft 6 is upwardly offset (i.e. the two permanent magnet rotors 5 are synchronously axially moved upwardly), the distances from the two permanent magnet rotors 5 to the corresponding enhancement windings decrease. If the enhancement windings are energized, the enhancement magnetic circuit 15 will pass through the permanent magnet rotor 5 and the enhancement winding, and the enhancement winding located above the permanent magnet rotor 5 will give the permanent magnet rotor 5 an upward magnetic pull force, so that the permanent magnet rotor 5 moves upwardly, resulting in an increase in the axial offset of the main shaft 6. Therefore, at this time, the two enhancement windings are not energized, so as to avoid increasing the axial offset of the main shaft 6.

[0058] When the main shaft 6 is downwardly offset (i.e. the two permanent magnet rotors 5 are synchronously axially moved downwardly), the distances from the two permanent magnet rotors 5 to the corresponding enhancement windings increase. If the enhancement windings are energized, the enhancement magnetic circuit 15 will pass through the permanent magnet rotor 5 and the enhancement winding, and the enhancement winding located above the permanent magnet rotor 5 will give the permanent magnet rotor 5 an upward magnetic pull force, so that the permanent magnet rotor 5 moves upwardly, resulting in a decrease in the axial offset of the main shaft 6. Therefore, at this time, the two enhancement windings are energized, so as to decrease the axial offset of the main shaft 6.

[0059] This way is suitable for the equipment in which the main shaft 6 has a downward axial offset trend, and the two enhancement windings can both exert an axial force on the corresponding permanent magnet rotor 5, so that the ability to correct the downward offset of the main shaft 6 is stronger. However, when the main shaft 6 is upwardly offset, energizing the enhancement windings will increase the offset, so this way is not suitable for the equipment in which the main shaft 6 has an upward offset trend.

[0060] Way two: the enhancement coils 4 of the two enhancement windings are respectively located on the lower side of the corresponding first radial arm 11, as shown in Figure 4 .

[0061] When the main shaft 6 is upwardly deflected (i.e. the two permanent magnets 5 are synchronously moved downwardly in the axial direction), the distance between the two permanent magnets 5 and the corresponding reinforcing windings is increased. If the reinforcing windings are energized, the reinforcing magnetic circuit 15 will pass through the permanent magnets 5 and the reinforcing windings, and the reinforcing windings below the permanent magnets 5 will give the permanent magnets 5 a downward magnetic pull, so as to drive the permanent magnets 5 to move downwardly, and the axial deflection of the main shaft 6 is reduced. Therefore, at this time, both of the reinforcing windings are energized, so as to reduce the axial deflection of the main shaft 6.

[0062] Conversely, when the main shaft 6 is downwardly deflected, if the reinforcing windings are energized, the reinforcing windings will also give the permanent magnets 5 a downward magnetic pull, so as to drive the permanent magnets 5 to move downwardly, and the axial deflection of the main shaft 6 is increased. Therefore, at this time, both of the reinforcing windings are not energized.

[0063] This mode is suitable for the equipment in which the main shaft 6 has an upward axial deflection tendency, and both of the reinforcing windings can exert a downward axial force on the corresponding permanent magnets 5, so as to have a stronger ability to correct the upward deflection of the main shaft 6. Conversely, in this mode, when the main shaft 6 is downwardly deflected, the energization of the reinforcing windings will increase the deflection, and therefore this mode is not suitable for the equipment in which the main shaft 6 has a downward deflection tendency.

[0064] Mode three: the reinforcing coils 4 of the two reinforcing windings are oppositely arranged (i.e. the reinforcing coil 4 above is located below the first radial arm 11 above, and the reinforcing coil 4 below is located above the first radial arm 11 above), as shown in FIG. 3. Figure 3

[0065] When the main shaft 6 is upwardly deflected, at this time, the reinforcing windings above are energized to give the permanent magnets 5 below a downward magnetic pull. At this time, the reinforcing windings below are not energized, because the magnetic field generated by the reinforcing windings below will give the permanent magnets 5 above an upward magnetic pull, and will instead strengthen the deflection.

[0066] Conversely, when the main shaft 6 is downwardly deflected, the reinforcing windings above are not energized, and the reinforcing windings below are energized to give the permanent magnets 5 below an upward magnetic pull, so as to drive the main shaft 6 to move upwardly and reduce the axial deflection.

[0067] In this mode, the two reinforcing windings are located between the two first radial arms 11, and therefore will not increase the axial length, which is beneficial to reduce the space of the equipment.

[0068] Mode four: the reinforcing coils 4 of the two reinforcing windings are oppositely arranged (i.e. the reinforcing coil 4 above is located above the first radial arm 11 above, and the reinforcing coil 4 below is located below the first radial arm 11 above)

[0069] ​When the main shaft 6 is upwardly deviated, the lower enhancement winding is energized at this time, giving the lower permanent magnet rotor 5 a downward magnetic pull. At this time, the upper enhancement winding is not energized, because the magnetic field generated by the upper enhancement winding after energization will give the upper permanent magnet rotor 5 an upward magnetic pull, which will instead strengthen the deviation.

[0070] Conversely, when the main shaft 6 is downwardly deviated, the lower enhancement winding is not energized, and the upper enhancement winding is energized, giving the upper permanent magnet rotor 5 an upward magnetic pull, driving the main shaft 6 to move upward and reducing the axial deviation.

[0071] It should be noted that in all the above ways, the enhancement magnetic circuit 15 generated by the enhancement coil 4 and the corresponding main magnetic circuit 14 are in the same direction. It should be noted that in the above ways, the magnetic field is mainly through the first radial arm 11 and not through the enhancement coil 4.

[0072] When the main shaft 6 does not produce axial deviation, the upper and lower enhancement windings can be selected to be energized, because the magnetic field generated by the enhancement coil 4 and the corresponding rotating coil 3 will increase the rotating driving force of the permanent magnet rotor 5; if the main shaft 6 does not have axial deviation and the radial main control force is insufficient, the enhancement winding can also adopt the same control strategy as the corresponding suspension coil 2, and generate the same magnetic field as the suspension coil 2, thereby enhancing the radial control force; the enhancement coil 4 can also use the single winding principle of the magnetic suspension motor to pass through the superimposed current in it, and simultaneously generate the suspension and rotating magnetic field, thereby simultaneously enhancing the rotating and radial suspension driving force.

[0073] Further, the first magnetic yoke 1 further comprises a second radial arm 12, which is in contact with and fixedly connected to the axial arm 10, and the enhancement coil 4 is sleeved outside the second radial arm 12.

[0074] Preferably, the second radial arm 12 is integrally formed with the axial arm 10.

[0075] Since the enhancement coil 4 mainly utilizes the leakage magnetic field of the permanent magnet rotor 5, and the added second radial arm 12 has better magnetic conductivity than the original hollow air, the utilization rate of the leakage magnetic field will be higher.

[0076] It should be noted that when the second radial arm 12 is not added and the enhancement coil 4 is not energized, the original axial suspension of the main shaft 6 mainly relies on the passive suspension of the magnetic resistance of the permanent magnet rotor 5. Taking the case where the main shaft 6 is upwardly deviated, at this time the original upper first radial arm 11 and lower first radial arm 11 will generate magnetic resistance due to the increase in air gap caused by the deviation of the permanent magnet rotor 5.

[0077] When the second radial arm 12 is added in mode one:

[0078] When the main shaft 6 is upwardly deflected, the distance between the two permanent magnets 5 and the corresponding first radial arm 11 increases, and the distance between the two permanent magnets 5 and the corresponding second radial arm 12 decreases. In order to inhibit the magnetic force lines of the permanent magnets 5 from passing through the corresponding second radial arm 12, the two reinforcing coils 4 of the reinforcing windings need to generate magnetic fields opposite to the corresponding rotating coils 3 at this time, thereby reducing the magnetic pull in the upward axial direction.

[0079] Conversely, when the main shaft 6 is downwardly deflected, the distance between the two permanent magnets 5 and the corresponding first radial arm 11 and the second radial arm 12 both increases. At this time, the two reinforcing coils 4 of the reinforcing windings need to generate magnetic fields same as the corresponding rotating coils 3, thereby enhancing the magnetic pull of the permanent magnets 5 in the upward direction. This way is better for inhibiting the deflection of the main shaft 6 with a downward deflection tendency.

[0080] When the second radial arm 12 is added in the second way:

[0081] When the main shaft 6 is upwardly deflected, the distance between the two permanent magnets 5 and the corresponding first radial arm 11 and the second radial arm 12 both increases. At this time, the two reinforcing coils 4 of the reinforcing windings need to generate magnetic fields same as the corresponding rotating coils 3, thereby enhancing the magnetic pull of the permanent magnets 5 in the upward direction. This way is better for inhibiting the deflection of the main shaft 6 with an upward deflection tendency.

[0082] Conversely, when the main shaft 6 is downwardly deflected, the distance between the two permanent magnets 5 and the corresponding first radial arm 11 increases, and the distance between the two permanent magnets 5 and the corresponding second radial arm 12 decreases. In order to inhibit the magnetic force lines of the permanent magnets 5 from passing through the corresponding second radial arm 12, the two reinforcing coils 4 of the reinforcing windings need to generate opposite magnetic fields (i.e. the magnetic path direction is opposite to the rotating coil 3) at this time, thereby reducing the magnetic pull in the downward axial direction.

[0083] When the second radial arm 12 is added in the third way:

[0084] As shown in Figure 5 the second radial arm 12 is added between the original two first radial arms 11. Taking the upward deflection of the main shaft 6 as an example, the distance between the upper permanent magnet 5 and the first radial arm 11 and the second radial arm 12 at the upper end both increases. The second radial arm 12 at the upper end generates a magnetic pull due to the energization of the reinforcing coil 4, and the first radial arm 11 generates a magnetic resistance, which together drive the upper permanent magnet 5 to move downwardly and reset.

[0085] However, the magnetic resistance force of the lower permanent magnet rotor 5 will be different from that without the second radial arm 12, because the upward displacement of the main shaft 6 makes the lower permanent magnet rotor 5 far away from the lower first radial arm 11, but close to the lower second radial arm 12. Therefore, the magnetic resistance force of the lower permanent magnet rotor 5 will not increase relatively, and the axial passive suspension effect of the lower end of the main shaft 6 will be weakened. This is because the magnetic circuit through the lower permanent magnet rotor 5 will pass through the second radial arm 12 more, and the magnetic flux through the first radial arm 11 will be less, and the magnetic resistance force of the first radial arm 11 to the permanent magnet rotor 5 will be smaller.

[0086] Therefore, the control mode of the reinforcing coil 4 is different from the above structure. When the main shaft 6 is displaced upward, the control mode of the upper reinforcing coil 4 remains unchanged (i.e. the magnetic circuit direction is the same as that of the upper rotating coil 3), but the control mode of the lower reinforcing coil 4 is opposite (i.e. the magnetic circuit direction is opposite to that of the lower rotating coil 3), mainly to inhibit the magnetic force line of the lower permanent magnet rotor 5 from closing through the second radial arm 12 to weaken the original axial passive suspension force.

[0087] Further, when the reinforcing coil 4 is located axially outside the two first radial arms 11, the axial arm 10 is formed with an axial extension arm 101 at the end, and the axial extension arm 101 is located radially outside the reinforcing coil 4. As shown in Figure 4 The lower reinforcing coil 4 is located axially outside the first radial arm 11, and the axial extension arm 101 reduces the air gap between the first magnetic yoke 1 and the lower reinforcing coil 4, thereby reducing the magnetic leakage.

[0088] Further, the main shaft 6 is made of a non-magnetic material, so as to avoid the formation of an axial magnetic circuit between the two permanent magnet rotors 5 in the main shaft 6.

[0089] It should be noted that the permanent magnet rotor 5 is subjected to magnetic pull force under the active control of the energized reinforcing coil 4, and the permanent magnet rotor 5 is subjected to magnetic resistance force under the active control of the non-energized reinforcing coil 4 (such as the first radial arm 11).

[0090] Further, it further comprises an axial sensor for detecting the axial position of the main shaft 6, and a controller for changing the on-off of the current in the reinforcing coil 4. The position of the main shaft 6 is detected by the axial sensor, and the detected position information is transmitted to the controller, and the controller judges whether the reinforcing coil 4 needs to be energized.

[0091] Embodiment two:

[0092] As shown in Figures 1 to 7 A motor using the magnetic suspension device of embodiment one: further comprising a housing 7, the stator assembly is fixedly connected with the housing 7, and the permanent magnet rotor 5 and the main shaft 6 do not contact the housing 7.

[0093] Since the two permanent magnet rotors 5 are placed coaxially at both ends of the main shaft, compared with the existing magnetic levitation thin-plate motor with only one permanent magnet rotor, this structure can better levitate and rotate a relatively long shaft.

[0094] Example 3:

[0095] like Figures 1 to 7 As shown, a pump using the motor described in Embodiment 2 further includes a pump housing 8 and an impeller 83. The pump housing 8 is fixed to the housing 7 and inserted into the inner cavity 70 of the housing 7. The pump housing 8 has an inlet 81 and an outlet 82. The permanent magnet rotor 5 and the main shaft 6 are located inside the pump housing 8. The impeller 83 is fixedly connected to the permanent magnet rotor 5 and / or the main shaft 6.

[0096] An impeller 73 is fixedly installed at one end of the main shaft 6. The magnetic levitation motor, combined with the pump head, can pump liquid media. Moreover, the permanent magnet force of the permanent magnet rotor 5 is greater than that of the magnetic levitation thin sheet motor with a single shaft of the same diameter and a thickness equal to the sum of the thickness of the two permanent magnet rotors 5 in the prior art. Therefore, the output power and torque of this embodiment are higher, which can better meet the needs of large flow or high head.

[0097] Since the impeller 73 experiences an upward axial force when rotating in the liquid, it tends to shift upwards. Therefore, the position of the reinforcing winding can be determined using method two (e.g., ...). Figure 4 As shown in the figure, this enhances the downward magnetic pull, achieving a better correction effect for the offset.

[0098] In some cases, smaller motors and pumps are required. In this case, the position of the reinforcing winding can be adopted in mode three, where the added reinforcing coil 4 is located between the two first radial arms 11 without increasing the volume of the motor and pump.

[0099] During operation, the main shaft 6 and impeller 73 rotate synchronously, drawing fluid in through inlet 81 and pumping it out through outlet 72. Because the main shaft 6 experiences radial fluid force at the end closest to impeller 83, the distances from the two permanent magnet rotors 5 to the point on the main shaft 6 where the radial fluid force is applied are different. When the radial force on the main shaft 6 is small, the magnetic resistance between the permanent magnet rotor 5 and the stator assembly can suppress the main shaft 6 from deflecting.

[0100] However, when the radial force on the main shaft 6 is too large, external forces need to be applied at both ends to suppress it. This requires applying different forces to the permanent magnet rotors 5 at both ends. In the presence of the second magnetic yoke 9, the radial control force is adjusted separately through two separate closed reinforcing magnetic circuits 15, which is active control. Because the two permanent magnet rotors 5 are at different distances from the load end, the lever arms of the applied radial force are different. Applying a small radial force to the permanent magnet rotor 5 with the longer lever arm can produce the same control force as the permanent magnet rotor 5 with the shorter lever arm. Therefore, making reasonable use of this difference can improve motor efficiency.

[0101] The utility model is described above by way of example, but the utility model is not limited to the above specific embodiments, any modification or change based on the utility model belongs to the range of the utility model claimed.

Claims

1. A magnetic levitation device with increased control capability, characterized in that It includes: The enhanced winding, the permanent magnet rotor (5), the main shaft (6) and the stator assembly, the two permanent magnet rotors (5) are coaxial and arranged in the up-down direction, the two permanent magnet rotors (5) are fixedly connected with the main shaft (6) respectively, the number of magnetic poles of the two permanent magnet rotors (5) is same and the arrangement direction of the magnetic poles is same, the two stator assemblies are respectively located outside the two permanent magnet rotors (5), the two stator assemblies respectively drive the two permanent magnet rotors (5) to suspend and rotate through magnetic force, the enhanced winding includes a plurality of enhanced coils (4), the enhanced coils (4) of the two enhanced windings are respectively arranged uniformly around the two permanent magnet rotors (5).

2. A magnetic levitation device with increased control capability according to claim 1, characterized in that: The stator assembly includes a first magnetic yoke (1) and a coil group, the coil group is sleeved and fixed outside the first magnetic yoke (1), the first magnetic yoke (1) and the coil group are arranged uniformly around the permanent magnet rotor (5), the enhanced coil (4) is fixedly connected with the first magnetic yoke (1).

3. A magnetic levitation device with increased control capability according to claim 2, characterized in that: The stator assembly further includes a second magnetic yoke (9), the two stator assemblies share the first magnetic yoke (1) and the second magnetic yoke (9), the second magnetic yoke (9) is located between the coil groups of the two stator assemblies and between the two enhanced coils (4), the second magnetic yoke (9) is annular, the main shaft (6) passes through the through hole in the middle of the second magnetic yoke (9), the first magnetic yoke (1) passes through the second magnetic yoke (9) in the up-down direction; It also includes a radial sensor and a controller, the radial sensor is used to detect the radial position of the main shaft (6), and the controller is used to change the current in the coil group.

4. A magnetic levitation device with increased control capability according to claim 3, characterized in that: The first magnetic yoke (1) includes an axial arm (10) and a first radial arm (11), the two ends of the axial arm (10) are fixedly connected with the first radial arm (11) respectively, the first radial arm (11) protrudes inward and is located radially outside the permanent magnet rotor (5), the coil group is sleeved outside the axial arm (10), the enhanced coil (4) corresponds to the first radial arm (11) one by one, and the enhanced coil (4) is located on the upper side and / or the lower side of the corresponding first radial arm (11).

5. A magnetic levitation device with increased control capability according to claim 4, characterized in that: The first magnetic yoke (1) further includes a second radial arm (12), the second radial arm (12) is in contact with and fixedly connected with the axial arm (10), and the enhanced coil (4) is sleeved outside the second radial arm (12).

6. The magnetic levitation device with increased control capabilities of claim 2, wherein: The axis of the enhanced coil (4) is perpendicular to the axis of the coil group. It also includes an axial sensor and a controller, the axial sensor is used to detect the axial position of the main shaft (6), and the controller is used to change the on-off of the current in the enhanced coil (4).

7. The magnetic levitation device with increased control capabilities of claim 4, wherein: When the enhanced coil (4) is located axially outside the two first radial arms (11), the axial arm (10) is formed with an end portion formed with an axial extension arm (101), and the axial extension arm (101) is located radially outside the enhanced coil (4).

8. The magnetic levitation device of claim 1, wherein: The main shaft (6) is made of a non-magnetic material.

9. An electric machine characterized by: The magnetic suspension device with increased control capability as claimed in any one of claims 1 to 8 is used, further including a housing (7), the stator assembly is fixedly connected with the housing (7), and the permanent magnet rotor (5) and the main shaft (6) are not in contact with the housing (7).

10. A pump characterized by: The electric machine as claimed in claim 9 is used, further comprising a pump shell (8) fixed with the machine shell (7) and inserted into the machine shell (7), the pump shell (8) is respectively formed with an inlet (81) and an outlet (82), the permanent magnet rotor (5) and the main shaft (6) are located in the pump shell (8), and the impeller (83) is fixedly connected with the permanent magnet rotor (5) and / or the main shaft (6).

Images