Brushless adjustable magnetic type permanent magnet eddy current coupler

Abstract

The invention provides a brushless magnetism-adjustable permanent magnet eddy current coupler which comprises a conductor rotor, a permanent magnet rotor and a rotary magnetic coupling resonator which are sequentially arranged in the axial direction of a rotating shaft, the transmitting end of the magnetic coupling resonator is arranged outside the permanent magnet eddy current coupler, and the receiving end of the magnetic coupling resonator is connected with the permanent magnet rotor and synchronously rotates along with the permanent magnet rotor. The magnetic field adjusting device is used for adjusting the magnetic field of the low-coercivity permanent magnet at the permanent magnet rotor; speed regulation is carried out by adjusting the magnetization intensity of the low-coercivity permanent magnet, and the speed regulation range of the coupler is enlarged.

Description

Technical Field

[0001] The present invention relates to the technical field of permanent magnet eddy current couplings, and particularly to a brushless magnetic field regulating type permanent magnet eddy current coupling. Background Art

[0002] With the successful development of high-performance magnetic materials such as neodymium iron boron, the speed regulation drive of permanent magnet eddy current couplings has emerged as the times require. Compared with the traditional variable frequency speed regulation drive and hydraulic coupling speed regulation drive, the speed regulation drive of permanent magnet eddy current couplings has the following advantages: ① no mechanical connection, small vibration and noise; ② tolerance of a certain misalignment error; ③ soft start and overload protection, reducing the impact current of the motor and extending the service life of the equipment; ④ stepless speed regulation, wide speed regulation range; ⑤ strong environmental adaptability; ⑥ simple structure, less maintenance. The permanent magnet eddy current coupling overcomes the problems existing in mechanical transmission such as vibration and noise, friction and wear, mechanical fatigue, overload breakage and high lubrication requirements, changes the traditional speed regulation drive concept, truly realizes green transmission, and has broad application prospects in the speed regulation drive systems of fans and pumps in industries such as electric power, iron and steel, petrochemical, and coal. Summary of the Invention

[0003] The present invention provides a brushless magnetic field regulating type permanent magnet eddy current coupling, which adjusts the magnetization intensity of low coercivity permanent magnets for speed regulation, increasing the speed regulation range of the coupling.

[0004] The present invention adopts the following technical solutions.

[0005] A brushless magnetic field regulating type permanent magnet eddy current coupling includes a conductor rotor, a permanent magnet rotor and a rotary magnetic coupling resonator sequentially arranged in the axial direction of the rotating shaft. The transmitting end of the magnetic coupling resonator is placed outside the permanent magnet eddy current coupling and remains stationary, and the receiving end of the magnetic coupling resonator is connected to the permanent magnet rotor and rotates synchronously with the permanent magnet rotor, for regulating the magnetic field of the low coercivity permanent magnets at the permanent magnet rotor.

[0006] The conductor rotor includes a disc-shaped conductor rotor core; an annular coil installation area is provided at the edge of the disc surface of the conductor rotor core, and a plurality of flat wire sector coils are densely arranged in a radial pattern at the coil installation area.

[0007] The permanent magnet rotor includes a permanent magnet rotor core fixed to the rotating shaft and a plurality of magnetic field regulating windings, and also includes a plurality of low coercivity permanent magnets AlNiCo and high coercivity permanent magnets NdFeB; each low coercivity permanent magnet AlNiCo is embedded between two high coercivity permanent magnets NdFeB to form a strip-shaped permanent magnet combination body, and each permanent magnet combination body is fixed to the disc-shaped permanent magnet rotor core in a radial pattern with the rotating shaft as the axis.

[0008] Each magnetic field regulating winding is arranged at the disk surface of the permanent magnet rotor core. The installation area of the magnetic field regulating winding is opposite to the coil installation area of the conductor rotor core, and the magnetic field regulating winding is adjacent to the flat wire sector coil of the conductor rotor.

[0009] The magnetic field regulating winding is powered by a magnetic coupling resonator. Both the receiving end and the transmitting end of the magnetic coupling resonator are annular. The receiving end of the magnetic coupling resonator is connected to each magnetic field regulating winding through a rotary rectifier, and the receiving end of the magnetic coupling resonator rotates synchronously with the permanent magnet rotor.

[0010] The receiving end of the magnetic coupling resonator is sleeved outside the permanent magnet rotor core. The receiving end coil is supported by a receiving end support and is connected to the magnetic field regulating winding at the permanent magnet rotor through the receiving end support.

[0011] The magnetic field regulating winding at the permanent magnet rotor is an exciting winding, and the disk surface gap between the permanent magnet rotor and the conductor rotor forms an air gap.

[0012] The receiving end coil of the receiving end of the magnetic coupling resonator and the transmitting end coil of the transmitting end of the magnetic coupling resonator are placed opposite to each other. The receiving end supplies current to the exciting winding on the permanent magnet rotor for magnetic field regulation through magnetic field coupling with the transmitting end. When the receiving end of the magnetic coupling resonator rotates synchronously with the permanent magnet rotor, the relative area of the receiving end coil and the transmitting end coil remains unchanged to maintain efficient transmission of power supply to the magnetic field regulating winding.

[0013] The brushless magnetic field regulating type permanent magnet eddy current coupler adjusts the magnetization intensity of the low coercivity permanent magnet to adjust the speed, so as to increase the speed regulation range of the coupler.

[0014] The method of adjusting the speed by adjusting the magnetization intensity of the low coercivity permanent magnet is specifically as follows: Set the initial permanent magnet working point of the permanent magnet rotor on the load line. When a reverse current pulse is applied, the initial permanent magnet working point moves downward along the demagnetization curve. When the pulse disappears, the working point rises along the recoil line and finally stabilizes at a new working point. The magnetization state of the new working point is lower than that of the initial working point. At this time, the permanent magnet magnetic flux of AlNiCo is opposite to the permanent magnet magnetic flux of NdFeB, and the air gap magnetic density decreases; When a positive current pulse is applied, the initial permanent magnet working point moves upward along the demagnetization curve. When the pulse disappears, the working point descends along the recoil line and finally stabilizes at a new working point. The magnetization state of the new working point is higher than that of the initial working point. At this time, the permanent magnet magnetic flux generated by AlNiCo is the same as the permanent magnet magnetic flux of NdFeB, and the air gap magnetic density increases; When the air gap magnetic density changes, the torque of the coupler changes accordingly, so as to realize the adjustment of the speed.

[0015] The present invention adjusts the speed by adjusting the magnetization intensity of the low coercivity permanent magnet, replacing the traditional speed regulation method of adjusting the air gap magnetic density, avoiding directly adjusting the mechanical structure of the coupler to adjust the relative position of the two rotors, and can be adjusted without directly adjusting the mechanical structure of the coupler to adjust the relative position of the two rotors. At the same time, the speed regulation range is increased. Brief Description of the Drawings

[0016] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments: Attached Figure 1 is an exploded view schematic diagram of the permanent magnet eddy current coupler in the specific embodiment of the present invention; Attached Figure 2 is a schematic diagram of the conductor rotor structure in the specific embodiment of the present invention; Attached Figure 3 is a schematic diagram of the permanent magnet rotor structure in the specific embodiment of the present invention; Attached Figure 4 is a schematic diagram of the structural principle of the rotary magnetic coupling resonator in the specific embodiment of the present invention; Attached Figure 5 is a schematic diagram of the structure of the transmitting end of the magnetic coupling resonator in the specific embodiment of the present invention; Attached Figure 6 is a schematic diagram of the structure of the receiving end of the magnetic coupling resonator in the specific embodiment of the present invention; Attached Figure 7 is a schematic diagram of the magnetic hysteresis loop of AlNiCo in the specific embodiment of the present invention; Attached Figure 8 is another exploded view schematic diagram of the permanent magnet eddy current coupler in the specific embodiment of the present invention; Attached Figure 9 is a schematic diagram of the method for switching the magnetic modulation winding in the specific embodiment of the present invention; Attached Figure 10 is a schematic diagram of the mechanical characteristic curve under different magnetization states (for constant torque load) in the specific embodiment of the present invention; In the figure: 1 - permanent magnet rotor; 2 - magnetic coupling resonator; 3 - receiving end of the magnetic coupling resonator; 4 - transmitting end of the magnetic coupling resonator; 5 - rotating shaft; 6 - conductor rotor core; 7 - flat wire sector coil; 8 - magnetic modulation winding; 9 - permanent magnet rotor core; 10 - conductor rotor; 11 - low coercivity permanent magnet AlNiCo; 12 - high coercivity permanent magnet NdFeB; 13 - transmitting end coil; 14 - receiving end coil; 15 - receiving end support. Specific Embodiments

[0017] As shown in the figure, a brushless magnetic flux-adjustable permanent magnet eddy current coupler includes a conductor rotor 10, a permanent magnet rotor 1, and a rotary magnetic coupling resonator 2 sequentially arranged in the axial direction of a rotating shaft 5. The transmitting end 4 of the magnetic coupling resonator is placed outside the permanent magnet eddy current coupler and remains stationary, while the receiving end 3 of the magnetic coupling resonator is connected to the permanent magnet rotor and rotates synchronously with the permanent magnet rotor, for adjusting the magnetic flux of the low coercivity permanent magnets at the permanent magnet rotor.

[0018] The conductor rotor 10 includes a disc-shaped conductor rotor core 6; an annular coil installation area is provided at the edge of the disc surface of the conductor rotor core, and a plurality of flat wire sector coils 7 are densely arranged radially in the coil installation area.

[0019] The permanent magnet rotor includes a permanent magnet rotor core 9 fixed to the rotating shaft, a plurality of magnetic flux adjustment windings 8, and also includes a plurality of low coercivity permanent magnets AlNiCo 11 and high coercivity permanent magnets NdFeB 12; each low coercivity permanent magnet AlNiCo is embedded between two high coercivity permanent magnets NdFeB to form a strip-shaped permanent magnet combination body, and each permanent magnet combination body is fixed to the disc-shaped permanent magnet rotor core radially with the rotating shaft as the axis; A plurality of magnetic flux adjustment windings are radially distributed on the disc surface of the permanent magnet rotor core.

[0020] Each magnetic flux adjustment winding is arranged on the disc surface of the permanent magnet rotor core, the installation area of the magnetic flux adjustment winding is opposite to the coil installation area of the conductor rotor core, and the magnetic flux adjustment winding is adjacent to the flat wire sector coil of the conductor rotor.

[0021] The magnetic flux adjustment winding is powered by the magnetic coupling resonator. The receiving end and the transmitting end of the magnetic coupling resonator are both annular. The receiving end of the magnetic coupling resonator is connected to each magnetic flux adjustment winding through a rotary rectifier, and the receiving end of the magnetic coupling resonator rotates synchronously with the permanent magnet rotor.

[0022] The receiving end of the magnetic coupling resonator is sleeved outside the permanent magnet rotor core, the receiving end coil is supported by a receiving end support, and is connected to the magnetic flux adjustment winding at the permanent magnet rotor through the receiving end support 15.

[0023] The magnetic flux adjustment winding at the permanent magnet rotor is an exciting winding, and an air gap is formed in the disc surface gap between the permanent magnet rotor and the conductor rotor.

[0024] The receiving end coil 14 of the receiving end of the magnetic coupling resonator and the transmitting end coil 13 of the transmitting end of the magnetic coupling resonator are placed opposite to each other. The receiving end supplies current to the exciting winding on the permanent magnet rotor for magnetic flux adjustment through magnetic field coupling with the transmitting end; when the receiving end of the magnetic coupling resonator rotates synchronously with the permanent magnet rotor, the relative area of the receiving end coil and the transmitting end coil remains unchanged to maintain efficient transmission of power supply to the magnetic flux adjustment winding.

[0025] The brushless magnetic flux - adjusted permanent - magnet eddy - current coupler adjusts the speed by adjusting the magnetization intensity of the low - coercivity permanent magnet to increase the speed - regulation range of the coupler.

[0026] The method of adjusting the speed by adjusting the magnetization intensity of the low - coercivity permanent magnet is as follows: Set the initial permanent - magnet working point of the permanent - magnet rotor on the load line. When a reverse - current pulse is applied, the initial permanent - magnet working point moves downward along the demagnetization curve. When the pulse disappears, the working point rises along the recoil line and finally stabilizes at a new working point. The magnetization state of the new working point is lower than that of the initial working point. At this time, the permanent - magnet magnetic flux of AlNiCo is opposite to the permanent - magnet magnetic flux of NdFeB, and the air - gap magnetic density decreases. When a forward - current pulse is applied, the initial permanent - magnet working point moves upward along the demagnetization curve. When the pulse disappears, the working point descends along the recoil line and finally stabilizes at a new working point. The magnetization state of the new working point is higher than that of the initial working point. At this time, the permanent - magnet magnetic flux generated by AlNiCo is the same as the permanent - magnet magnetic flux of NdFeB, and the air - gap magnetic density increases. When the air - gap magnetic density changes, the torque of the coupler changes accordingly, thereby realizing the adjustment of the rotational speed.

[0027] Example 1: This example provides a brushless magnetic flux - adjusted permanent - magnet eddy - current coupler, as Figure 1 shown, which includes a conductor rotor, a permanent - magnet rotor, and a rotary magnetic - coupling resonator. The permanent - magnet eddy - current coupler is arranged axially in sequence as the conductor rotor 1, the permanent - magnet rotor 1, and the rotary magnetic - coupling resonator. The transmitting end of the rotary magnetic - coupling resonator is placed outside the permanent - magnet eddy - current coupler and remains stationary. The receiving end of the rotary magnetic - coupling resonator is connected to the permanent - magnet rotor and rotates synchronously with the permanent - magnet rotor to adjust the magnetic flux of the low - coercivity permanent magnet on the permanent - magnet rotor.

[0028] The conductor rotor is composed of an iron core and a coil. The coil is a flat - wire sector - shaped coil. The permanent - magnet rotor is composed of an iron core, a low - coercivity permanent magnet AlNiCo, a high - coercivity permanent magnet NdFeB, and a magnetic - flux - adjusting winding. The low - coercivity permanent magnet AlNiCo is embedded between two high - coercivity permanent magnets NdFeB.

[0029] In the rotary magnetic - coupling resonator, the high - frequency inverter power supply is connected to the transmitting end of the magnetic - coupling resonator and remains stationary outside the coupler. The receiving end of the magnetic - coupling resonator is connected to the magnetic - flux - adjusting winding on the permanent - magnet rotor of the coupler through a rotary rectifier and rotates synchronously with the permanent - magnet rotor. The transmitting - end coil and the receiving - end coil are placed opposite to each other and keep the relative area unchanged to ensure efficient energy transmission. The receiving end supplies current to the excitation winding on the permanent - magnet rotor through magnetic - field coupling with the transmitting end for magnetic - flux adjustment.

[0030] The magnetic - flux - adjusting principle is as follows: The AlNiCo hysteresis loop is as Figure 7As shown, when a reverse current pulse is applied, the permanent magnet operating point moves from P 0 to Q 0 . When the pulse disappears, the operating point rises along the recoil line Q 0 P 1 and finally stabilizes at the new operating point P 1 . P 1 The magnetization state is lower than P 0 . At this time, the permanent magnet magnetic flux of AlNiCo is opposite to that of NdFeB, and the air-gap magnetic density decreases. When a positive current pulse is applied, the permanent magnet operating point moves from P 2 to R 2 , and then from P 2 to R 1 . When the pulse disappears, the operating point descends along the recoil line R 1 P 1 and finally stabilizes at the new operating point P 1 . P 1 The magnetization state is higher than P 2 . At this time, the permanent magnet magnetic flux generated by AlNiCo is the same as that of NdFeB, and the air-gap magnetic density increases. When the air-gap magnetic density changes, the torque of the coupler changes accordingly, thereby realizing the adjustment of the rotational speed.

[0031] In this embodiment, the conductor rotor structure is as shown in Figure 2 .

[0032] In this embodiment, the permanent magnet rotor structure is as shown in Figure 3 .

[0033] In this embodiment, the rotary magnetic coupling resonator structure is as shown in Figure 4 .

[0034] In this embodiment, the magnetic coupling resonator transmitting end structure is as shown in Figure 5 .

[0035] In this embodiment, the magnetic coupling resonator receiving end structure is as shown in Figure 6 .

[0036] Embodiment 2: In this example, a brushless magnetic flux regulation type permanent magnet eddy current coupling magnetic flux regulation speed control method is provided. The permanent magnet rotor adopts two speed regulation modes: memory magnetic flux regulation and pole-changing magnetic flux regulation. The magnetic flux regulation winding is powered by a rotary magnetic coupling resonator. As Figure 4 shown, the high-frequency inverter power supply is connected to the transmitting end in the magnetic coupling resonator and remains stationary outside the magnetic coupler. The receiving end is connected to the magnetic flux regulation winding on the permanent magnet rotor through a rotary rectifier and rotates synchronously with the permanent magnet rotor. The transmitting end coil and the receiving end coil are placed opposite to each other and keep the relative area unchanged to ensure efficient energy transmission. The specific overall machine diagram is as Figure 2 shown.

[0037] In this example, after an alternating magnetic field is generated when a current is passed through the transmitting end coil, an induced current is generated in the receiving end coil to supply power to the magnetic flux regulation winding.

[0038] The pole-changing speed regulation adopts a multi-permanent magnet pole number mode pole-changing magnetic flux regulation speed control method. As Figure 9 shown, by bypassing two adjacent NdFeB magnetic paths with AlNiCo, the permanent magnet rotor can operate in three permanent magnet pole number modes: 18 poles, 9 poles, and 0 poles.

[0039] For the three permanent magnet pole number modes of 18 poles, 9 poles, and 0 poles, the switching method of the magnetic flux regulation winding is as follows: as Figure 9 shown, the magnetic flux regulation winding is divided into two parts, which are connected in series respectively, controlled by different relays, and the phase-split magnetic flux regulation winding is connected to the rotary rectifier. By controlling the on-off of relays KM1 and KM2, the magnetic flux regulation winding of the permanent magnet rotor can be switched, and corresponding saturated magnetization or completely demagnetized current pulses can be applied to realize the operation of the coupler in three permanent magnet pole number modes of 18 poles, 9 poles, and 0 poles.

[0040] Considering the load conditions, permanent magnet fatigue, and temperature effects, a brushless magnetic flux regulation type permanent magnet eddy current coupling composite magnetic flux regulation speed control technology is adopted. As Figure 10 shown, mechanical characteristic curves of the brushless magnetic flux regulation type permanent magnet eddy current coupling in three permanent magnet pole number modes of 18 poles, 9 poles, and 0 poles and the corresponding limited magnetization states are established.

[0041] According to the mechanical characteristic curves, when the load speed remains unchanged, increasing the magnetization intensity of the permanent magnet, the load torque that the system can bear becomes larger; decreasing the magnetization intensity of the permanent magnet, the load torque that the system can withstand decreases, that is, different torque intervals are divided at the same slip.

[0042] The load torque is divided into constant torque load and parabolic load. The speed regulation range is judged by the intersection points of different loads and the mechanical characteristic curves. According to the load torque type and the torque interval to which the load torque belongs, based on loss optimization distribution, the permanent magnet pole number mode and the corresponding limited magnetization state are reasonably selected to realize the wide-area and high-efficiency operation of the brushless magnetic flux regulation type permanent magnet eddy current coupling.

[0043] For a constant torque load, by applying an exciting current to reduce the magnetization state of the soft magnetic body, the operating state of the magnetic coupler can achieve the effect of keeping the output torque unchanged while increasing the rotational speed; by applying an exciting current to increase the magnetization state of the soft magnetic body, the operating state of the magnetic coupler can achieve the effect of keeping the rotational speed unchanged while increasing the output torque.

[0044] For a parabolic load, by applying an exciting current to change the magnetization state of the soft magnetic body, the effect of increasing / decreasing the output torque while increasing / decreasing the rotational speed can be achieved.

Claims

1. A brushless magnetic-adjustable permanent magnet eddy current coupler, characterized in that: The invention comprises a conductor rotor, a permanent magnet rotor and a rotating magnetic coupling resonator which are sequentially arranged in the axial direction of the rotating shaft. The transmitting end of the magnetic coupling resonator is arranged outside the permanent magnet eddy current coupler. The receiving end of the magnetic coupling resonator is connected to the permanent magnet rotor and rotates synchronously with the permanent magnet rotor, and is used for magnetically adjusting the low coercive force permanent magnet at the permanent magnet rotor.

2. A brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 1, characterized in that: The conductor rotor comprises a disc-shaped conductor rotor core; a ring-shaped coil installation area is arranged at the edge of the disc surface of the conductor rotor core, and a plurality of flat wire sector coils are densely arranged in a radial shape at the coil installation area.

3. A brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 2, characterized in that: The permanent magnet rotor includes a permanent magnet rotor core fixed to a rotating shaft and a plurality of magnetic tuning windings, and also includes a plurality of low coercive force permanent magnets AlNiCo and high coercive force permanent magnets NdFeB; each low coercive force permanent magnet AlNiCo is embedded between two high coercive force permanent magnets NdFeB to form a bar-shaped permanent magnet assembly, and each permanent magnet assembly is fixed to the disc-shaped permanent magnet rotor core in a radial shape with the rotating shaft as the axis.

4. A brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 3, characterized in that: Each magnetic tuning winding is arranged on the disk surface of the permanent magnet rotor core, the installation area of ​​the magnetic tuning winding is opposite to the coil installation area of ​​the conductor rotor core, and the magnetic tuning winding is adjacent to the flat wire sector coil of the conductor rotor.

5. A brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 4, characterized in that: The magnetic tuning winding is powered by a magnetic coupling resonator. The receiving end and the transmitting end of the magnetic coupling resonator are both ring-shaped. The receiving end of the magnetic coupling resonator is connected to each magnetic tuning winding through a rotating rectifier. The receiving end of the magnetic coupling resonator rotates synchronously with the permanent magnet rotor.

6. The brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 5, characterized in that: The receiving end of the magnetic coupling resonator is sleeved outside the permanent magnet rotor core, the receiving end coil is supported by a receiving end support, and is connected to the magnetic tuning winding at the permanent magnet rotor through the receiving end support.

7. The brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 5, characterized in that: The magnetic field regulating winding at the permanent magnet rotor is an excitation winding, and the disk surface gap between the permanent magnet rotor and the conductor rotor forms an air gap.

8. The brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 7, characterized in that: The receiving end coil of the magnetic coupling resonator receiving end is placed opposite to the transmitting end coil of the magnetic coupling resonator transmitting end. The receiving end supplies current to the excitation winding on the permanent magnet rotor for magnetic adjustment through magnetic field coupling with the transmitting end. When the receiving end of the magnetic coupling resonator rotates synchronously with the permanent magnet rotor, the relative area of ​​the receiving end coil and the transmitting end coil remains unchanged to maintain efficient transmission of power supply to the magnetic adjustment winding.

9. The brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 8, characterized in that: The brushless magnetic-adjustable permanent magnet eddy current coupler adjusts the speed by adjusting the magnetization intensity of the low coercive force permanent magnet to increase the speed regulation range of the coupler.

10. The brushless magnetic-adjustable permanent magnet eddy current coupler according to claim 9, characterized in that: The method of speed regulation by adjusting the magnetization intensity of the low coercive force permanent magnet is as follows: the initial permanent magnet working point of the permanent magnet rotor is set on the load line. When a reverse current pulse is applied, the initial permanent magnet working point moves downward along the demagnetization curve. When the pulse disappears, the working point rises along the recovery line and finally stabilizes at a new working point. The magnetization state of the new working point is lower than the initial working point. At this time, the permanent magnet flux of AlNiCo is opposite to the permanent magnet flux of NdFeB, and the air gap magnetic density is reduced. When a forward current pulse is applied, the initial permanent magnet working point moves upward along the demagnetization curve. When the pulse disappears, the working point drops along the recovery line and finally stabilizes at a new working point. The magnetization state of the new working point is higher than the initial working point. At this time, the permanent magnet flux generated by AlNiCo is in the same direction as the permanent magnet flux of NdFeB, and the air gap flux density increases. When the air gap flux density changes, the torque of the coupler changes accordingly, thereby achieving speed adjustment.

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