A stator and a permanent magnet synchronous servo motor

Abstract

The present invention discloses a stator and a permanent magnet synchronous servo motor, belonging to the technical field of motors, to solve the problem that the coupling effect of the controller harmonics generates high-order harmonics and low-order harmonics, making the magnetic field of the motor uneven, increasing the torque ripple of the motor, generating relatively large electromagnetic noise, and also increasing the losses of the motor. A stator of the present invention is provided with U, V, and W three-phase windings on the stator, and a harmonic reduction circuit is connected to the input ends of the three-phase windings. The harmonic reduction circuit is used to filter out high-order and low-order harmonics during the operation of the motor. By connecting a harmonic reduction circuit to the connection ends of the three-phase windings of the motor, the high-order and low-order harmonics at the output end of the controller can be filtered out, so that the magnetic field of the motor is not affected by the harmonics, the uniformity of the motor magnetic field can be improved, the magnetic field roundness can be improved, the harmonic losses of the motor can be reduced, the efficiency of the motor can be improved, and the electromagnetic noise of the motor can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and particularly to a stator and a permanent magnet synchronous servo motor. Background Art

[0002] At present, permanent magnet servo motors have the characteristics of high efficiency and high integration, and are widely used in various industries. However, due to the harmonic disturbance of the controller (servo driver) during the motor control process, the non-sinusoidal distribution of the magnetic field of the permanent magnet motor and the influence of the tooth-slot air gap change directly affect the stable operation of the motor. Due to the coupling effect of the controller harmonics, high-order harmonics and low-order harmonics are generated, making the magnetic field of the motor uneven, increasing the torque ripple of the motor, generating relatively large electromagnetic noise, and also increasing the loss of the motor, reducing the efficiency of the motor. Summary of the Invention

[0003] In view of this, the present invention discloses a stator and a permanent magnet synchronous servo motor to solve the problems that the coupling effect of the controller harmonics generates high-order harmonics and low-order harmonics, making the magnetic field of the motor uneven, increasing the torque ripple of the motor, generating relatively large electromagnetic noise, and also increasing the loss of the motor.

[0004] The technical solution adopted by the present invention to achieve the above object is as follows:

[0005] In the first aspect of the present invention, a stator is disclosed. U, V, and W three-phase windings are provided on the stator, and a harmonic reduction circuit is connected to the input ends of the three-phase windings. The harmonic reduction circuit is used to filter out high-order and low-order harmonics during the operation of the motor.

[0006] Further, an inductance coil is connected in series to the input end of each phase winding, and a parallel-connected filter capacitor and resistor are electrically connected between the input ends of any two-phase windings. The inductance coil connected in series to each phase winding and the filter capacitor and resistor connected in parallel between any two-phase windings form the harmonic reduction circuit.

[0007] Further, an inductance iron core extending along the radial direction of the stator is provided on the yoke of the stator. The number of the inductance iron cores is 3n, where n is an integer greater than or equal to 1. An inductance coil is wound around each inductance iron core, and a magnetic isolation slot is provided at a position corresponding to the inductance iron core on the stator. The magnetic isolation slot is used to block the magnetic path between the inductance coil and the winding.

[0008] Further, the inductance iron core is located inside the yoke of the stator and extends along the center of the stator, and the inductance iron core is located in the tooth-slot of the stator. Magnetic isolation teeth are respectively provided on both sides of the inductance coil along the circumferential direction of the stator, and the magnetic isolation teeth are connected to the yoke of the stator.

[0009] Further, 3n groups of notches extending along the radial direction of the stator are provided on the outer circumference of the yoke of the stator, where n is an integer greater than or equal to 1, the number of notches in each group is two, and the yoke of the stator forms the inductive iron core between each group of notches.

[0010] Further, the number and inductive reactance of the inductive coils connected in series in each of the three-phase windings are equal, the number of the filter capacitors and resistors connected in parallel between any two of the two-phase windings is equal, the capacitance values of the filter capacitors are equal, and the resistance values of the resistors are also equal.

[0011] Further, the height H2 of the inductive iron core is less than the height H1 of the inductive iron core, that is, H2 < H1.

[0012] Further, the length W2 of the inductive iron core is less than the length W1 of the tooth part, that is, W2 < W1.

[0013] Further, the inductive reactance L of any one of the inductive coils satisfies:

[0014]

[0015] where U is the power supply voltage, P N is the output power of the motor, and K is a constant.

[0016] Further, the constant K satisfies: 0.2 ≤ K ≤ 0.6.

[0017] Further, the inductive iron cores are evenly arranged along the circumferential direction of the stator.

[0018] In a second aspect of the present invention, a permanent magnet synchronous servo motor is disclosed, including a stator as described in the first aspect.

[0019] Beneficial effects: By connecting a harmonic reduction circuit to the access ends of the three-phase windings of the motor, the high-order and low-order harmonics at the outlet end of the controller can be filtered out, so that the magnetic field of the motor is not affected by the harmonics, the uniformity of the motor magnetic field can be improved, the roundness of the magnetic field can be improved, the harmonic loss of the motor can be reduced, the efficiency of the motor can be improved, and the electromagnetic noise of the motor can be reduced. Description of the Drawings

[0020] By referring to the accompanying drawings and describing its exemplary embodiments in detail, the above and other objectives, features, and advantages of the present invention will become more obvious. The following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 An isometric view of the stator in Embodiment 1 is shown;

[0022] Figure 2 Shows the front view of the stator of Embodiment 1;

[0023] Figure 3 Shows the side view of the stator of Embodiment 1;

[0024] Figure 4 Shows the schematic diagram of the connection between the harmonic circuit and the three-phase winding in Embodiment 1;

[0025] Figure 5a Shows the structure of the first magnetic isolation slot in Embodiment 1;

[0026] Figure 5b Shows the structure of the second magnetic isolation slot in Embodiment 1;

[0027] Figure 5c Shows the structure of the third magnetic isolation slot in Embodiment 1;

[0028] Figure 5d Shows the structure of the fourth magnetic isolation slot in Embodiment 1;

[0029] Figure 6 Shows the schematic diagram of the first harmonic circuit in Embodiment 1. Detailed implementation manners

[0030] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms of "a", "the" and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. "Plural" generally includes at least two, but does not exclude the case of including at least one.

[0032] It should be understood that the term " / and / " used herein is only a description of the associated relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0033] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a commodity or system comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or elements inherent to such commodity or system. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the commodity or system comprising said element.

[0034] To further elaborate on the technical solutions in the present invention, in combination with Figures 1-6 , the following specific embodiments are provided.

[0035] Embodiment 1

[0036] In this embodiment, a stator is provided. As Figures 1-4 shown, U, V, and W three-phase windings are provided on the stator. Each phase winding is wound around the tooth part a of the stator. The input ends of the three-phase windings are connected to a harmonic reduction circuit 10, and the harmonic reduction circuit 10 is used to filter out high-order and low-order harmonics during the operation of the motor.

[0037] As Figure 4 shown, an inductance coil 11 is connected in series at the input end of each phase winding. A parallel-connected filter capacitor 12 and resistor 13 are electrically connected between the input ends of any two-phase windings. The inductance coil 11 connected in series with each phase winding and the filter capacitor 12 and resistor 13 connected in parallel between any two-phase windings form the harmonic reduction circuit 10.

[0038] Furthermore, as Figures 1-3 shown, an inductance iron core 20 extending along the radial direction of the stator is provided on the yoke part of the stator. The number of the inductance iron cores 20 is 3n, where n is an integer greater than or equal to 1. An inductance coil 11 is wound around each inductance iron core 20. A magnetic isolation slot c is provided at a position corresponding to the inductance iron core 20 on the stator. The magnetic isolation slot c is used to block the magnetic path between the inductance coil 11 and the winding, prevent the magnetic path of the inductance coil 11 from coupling with the magnetic path of the winding, and ensure the uniformity of the magnetic field distribution in the stator.

[0039] In an implementation manner of this embodiment, the inductance iron core 20 is located inside the inner side a of the yoke part of the stator and extends along the center of the stator, and the inductance iron core 20 is located in the tooth slot of the stator. Magnetic isolation teeth 30 are respectively provided on both sides of the inductance coil 11 along the circumferential direction of the stator, and the magnetic isolation teeth 30 are connected to the yoke part a of the stator. Since the inductance iron core 20 is located inside the inner side a of the yoke part of the stator, the structure of the magnetic isolation slot c can be various. Three arrangement methods of the magnetic isolation slot c are exemplified in this embodiment. As Figure 5aAs shown, the magnetic isolation groove c is a long groove. One of the long grooves is perpendicular to the extending direction of the inductor core 20 and is arranged on the yoke b of the stator. On both sides of the long groove, there are also two short long grooves with lengths shorter than that of the long groove. The positions of the short long grooves correspond to the positions of the magnetic isolation teeth 30, and the extending direction of the end long groove is the same as that of the magnetic isolation teeth 30. The structure of the magnetic isolation groove c can also be Figure 5b In the structure, the magnetic isolation groove c is a waist-shaped groove, which extends along the circumferential direction of the stator and is arranged on the yoke a of the stator. The position of the magnetic isolation groove c corresponds to the position of the magnetic isolation teeth 30. As Figure 5c shown, the magnetic isolation groove c forms a notch at the end of the inductor core 20. The length direction of the notch is the same as the extending direction of the inductor core 20. And three circular magnetic isolation grooves c are arranged on the yoke of the stator. One of the circular magnetic isolation grooves c is located on the yoke a of the stator and corresponds to the position of the inductor core 20. The other two circular magnetic isolation grooves c are distributed on both sides of the one circular magnetic isolation groove c and correspond to the positions of the coil grooves. The shape of the magnetic isolation groove c can also be other shapes such as a square, etc., which are not listed one by one here.

[0040] In one embodiment, 3n groups of notches g extending along the radial direction of the stator are provided on the outer circumference of the yoke of the stator, where n is an integer greater than or equal to 1. The number of notches g in each group is two. The inductor core 20 is formed between each group of the notches g on the yoke of the stator. The structure of the magnetic isolation groove c on the inductor core 20 is as Figure 5d shown. The magnetic isolation groove c is two waist-shaped grooves, which are symmetric with respect to the inductor core 20. The waist-shaped grooves bend towards the direction of the notch. The position of each waist-shaped groove corresponds to the position of each notch g, and the extending length of the waist-shaped groove is greater than the maximum width of the notch g, which can play a role in blocking the magnetic path of the inductor core 20 and preventing magnetic path coupling with the winding. Since the inductor core 20 is arranged on the side opposite to the tooth part of the stator, the magnetic isolation teeth 30 are not provided.

[0041] The magnetic isolation teeth 30 are connected to the yoke b of the stator. Coil grooves for accommodating the inductor coils 11 are respectively formed between the two magnetic isolation teeth 30 and the inductor core 20. The inductor coils 11 have the characteristic of blocking alternating current and passing direct current, which can filter out the high-order harmonics at the output end of the controller. At the same time, the capacitors electrically connected between any two-phase windings can play a role in filtering out the low-order harmonics and can filter out the low-order harmonics at the output end of the controller.

[0042] Further, the number and inductive reactance of the inductance coils 11 connected in series in each of the three-phase windings are equal, and the number of the filter capacitors 12 and resistors 13 connected in parallel between any two phases and the two-phase windings is equal. The capacitance values of the filter capacitors 12 are equal, and the resistance values of the resistors 13 are also equal, so as to ensure uniform magnetic circuit distribution of the stator. The number of the filter capacitors 12 connected in parallel between the U-phase winding and the V-phase winding can be 1. The number of the filter capacitors 12 connected in parallel between the U-phase winding and the W-phase winding and between the W-phase winding and the V-phase winding should also ensure the same number as that of the filter capacitors 12 between the U-phase winding and the V-phase winding, the same resistance value, the same number of resistors between two phases and two-phase windings, and the same resistance value. As Figure 6 shown, in the harmonic reduction circuit 10, three inductance coils 11 (L1, L2, and L3 in the figure respectively) are connected in parallel, and two capacitors (C1 and C2, C3 and C4, C5 and C6 in the figure respectively) and one resistor (R1 - R3 in the figure respectively) are connected in parallel between two adjacent inductance coils 11. The harmonic reduction circuit 10 can also adopt Figure 4 the connection method shown, that is, two capacitors (C1 - C3 in the figure respectively) and one resistor (R1 - R3 in the figure respectively) are connected in parallel between two adjacent inductance coils 11.

[0043] In this embodiment, there can be various wiring forms for the three-phase windings on the stator. The specific wiring forms are the same as those in the prior art and will not be elaborated here.

[0044] To further avoid the influence of the magnetic field of the inductance iron core on the internal magnetic field of the stator, the height H2 of the inductance iron core is less than the height of the inductance iron core H1, that is, H2 < H1. The length W2 of the inductance iron core is less than the length W1 of the tooth part, that is, W2 < W1.

[0045] Specifically, the inductive reactance L of any one of the inductance coils satisfies:

[0046]

[0047] wherein, U is the power supply voltage, P N is the output power of the motor, and K is a constant.

[0048] The constant K satisfies: 0.2 ≤ K ≤ 0.6. Through the above formula and the limitation of the constant K, high-order harmonics can be filtered out.

[0049] The inductance iron cores are uniformly arranged along the circumferential direction of the stator.

[0050] Embodiment 2

[0051] The present invention provides a permanent magnet synchronous servo motor, including a stator as described in Embodiment 1.

[0052] The exemplary embodiments of the present disclosure have been specifically shown and described above. It should be understood that the present disclosure is not limited to the detailed structures, arrangements, or implementation methods described herein; rather, the present disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A stator, on which three-phase windings U, V, and W are provided, characterized in that, A harmonic reduction circuit is connected to the input ends of the three-phase windings, and the harmonic reduction circuit is used to filter out high-order and low-order harmonics during the operation of the motor; The inductor core is located inside the yoke of the stator and extends along the center of the stator, and the inductor core is located in the tooth grooves of the stator. Magnetic isolation teeth are respectively arranged on both sides of the inductor coil along the circumferential direction of the stator, and the magnetic isolation teeth are connected to the yoke of the stator; An inductor coil is connected in series to the input end of each phase winding. A parallel-connected filter capacitor and resistor are electrically connected between the input ends of any two-phase windings. The inductor coil connected in series with each phase winding and the parallel-connected filter capacitor and resistor between any two-phase windings form the harmonic reduction circuit; The yoke of the stator is provided with inductor cores extending along the radial direction of the stator. The number of the inductor cores is 3n, where n is an integer greater than or equal to 1. An inductor coil is wound around each inductor core. A magnetic isolation groove is provided at a position on the stator corresponding to the inductor core, and the magnetic isolation groove is used to block the magnetic path between the inductor coil and the winding.

2. The stator according to claim 1, characterized in that, 3n groups of notches extending along the radial direction of the stator are provided on the outer circumference of the yoke of the stator, where n is an integer greater than or equal to 1. The number of notches in each group is two, and the inductor core is formed between each group of notches on the yoke of the stator.

3. A stator according to claim 2, characterized in that The number and inductive reactance of the inductor coils respectively connected in series to the three-phase windings are equal. The number of the parallel-connected filter capacitors and resistors between any two-phase windings and the two-phase windings is equal. The capacitance values of the filter capacitors are equal, and the resistance values of the resistors are also equal.

4. A stator according to any one of claims 1-3, characterized in that The height H2 of the inductor core is less than the height H1 of the tooth part of the stator, that is, H2 < H1.

5. A stator according to any one of claims 1-3, characterized in that The length W2 of the inductor core is less than the length W1 of the tooth part of the stator, that is, W2 < W1.

6. A stator according to any one of claims 1 to 3, characterized in that, The inductive reactance L of any one of the inductor coils satisfies: Among them, U is the power supply voltage, P N is the motor output power, and K is a constant.

7. A stator according to claim 6, wherein, The constant K satisfies: 0.2 ≤ K ≤ 0.

6.

8. A stator according to any one of claims 1-3, characterized in that, The inductor cores are arranged uniformly along the circumferential direction of the stator.

9. A permanent magnet synchronous servo motor, characterized in that, Including a stator according to any one of claims 1-8.

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