CN113726038A

CN113726038A - Stator and permanent magnet synchronous servo motor

Info

Publication number: CN113726038A
Application number: CN202111069972.2A
Authority: CN
Inventors: 张继胤; 徐常升; 魏会军; 王伟宇; 董天福; 程海珍
Original assignee: Gree Green Refrigeration Technology Center Co Ltd of Zhuhai
Current assignee: Gree Green Refrigeration Technology Center Co Ltd of Zhuhai; Zhuhai Gree Energy Saving Environmental Protection Refrigeration Technology Research Center Co Ltd
Priority date: 2021-09-13
Filing date: 2021-09-13
Publication date: 2021-11-30

Abstract

The invention discloses a stator and a permanent magnet synchronous servo motor, which belong to the technical field of motors, so as to solve the coupling effect of the harmonics of the controller, generate high-order harmonics and low-order harmonics, make the magnetic field of the motor uneven, and increase the frequency of the motor. Torque ripple will generate large electromagnetic noise and increase the loss of the motor. The present invention is a stator, wherein U, V, W three-phase windings are arranged on the stator, and the input ends of the three-phase windings are connected with a harmonic reduction circuit, and the harmonic reduction circuit is used to filter out the harmonics when the motor is running. higher and lower harmonics. The invention connects the harmonic reduction circuit at the access end of the three-phase winding of the motor, which can filter out the high-order and low-order harmonics at the outlet end of the controller, so that the magnetic field of the motor is not affected by the harmonics, and the uniformity of the magnetic field of the motor can be improved. Improve the roundness of the magnetic field, reduce the harmonic loss of the motor, improve the efficiency of the motor, and reduce the electromagnetic noise of the motor.

Description

Stator and permanent magnet synchronous servo motor

Technical Field

The invention relates to the technical field of motors, in particular to a stator and a permanent magnet synchronous servo motor.

Background

The permanent magnet servo motor has the characteristics of high efficiency, high integration level and the like at present, and is widely applied to various industries. However, due to the harmonic disturbance influence of a controller (servo driver) in the motor control process, the non-sinusoidal distribution of the magnetic field of the permanent magnet motor is influenced by the change of the air gap of the tooth slot, so that the stable operation of the motor is directly influenced, and due to the coupling effect of the harmonic wave of the controller, higher harmonic waves and lower harmonic waves are generated, so that the magnetic field of the motor is uneven, the torque pulsation of the motor is increased, larger electromagnetic noise can be generated, the loss of the motor can be increased, and the efficiency of the motor is reduced.

Disclosure of Invention

In view of the above, the invention discloses a stator and a permanent magnet synchronous servo motor, which are used for solving the problems that due to the coupling effect of controller harmonics, higher harmonics and lower harmonics are generated, the magnetic field of the motor is not uniform, the torque pulsation of the motor is increased, larger electromagnetic noise is generated, and the loss of the motor is increased.

In order to achieve the above object, the invention adopts the following technical scheme:

the invention discloses a stator, wherein U, V, W three-phase windings are arranged on the stator, a harmonic reduction circuit is connected to the input ends of the three-phase windings, and the harmonic reduction circuit is used for filtering higher harmonics and lower harmonics generated during the operation of a motor.

Furthermore, the input end of each phase of winding is connected with an inductance coil in series, a filter capacitor and a resistor which are connected in parallel are electrically connected between the input ends of any two phases of windings, and the inductance coil which is connected with each phase of winding in series and the filter capacitor and the resistor which are connected in parallel between any two phases of windings form the harmonic reduction circuit.

Furthermore, the yoke portion of the stator is provided with inductance cores extending along the radial direction of the stator, the number of the inductance cores is 3n, n is an integer greater than or equal to 1, each inductance core is wound with an inductance coil, a magnetic isolation groove is arranged at a position on the stator corresponding to the inductance core, and the magnetic isolation groove is used for blocking the inductance coil and a magnetic circuit of the winding.

Further, inductance core is located the yoke portion inboard of stator and along the center of stator extends, just inductance core is located in the tooth's socket of stator, inductance coil follows stator circumferential direction's both sides are equipped with the magnetic isolation tooth respectively, the magnetic isolation tooth is connected on the yoke portion of stator.

Furthermore, 3n groups of gaps extending along the radial direction of the stator are arranged on the outer circumference of the yoke part of the stator, n is an integer greater than or equal to 1, the number of each group of gaps is two, and the yoke part of the stator forms the inductance core between each group of gaps.

Furthermore, the number and the inductive reactance of the inductance coils which are respectively connected in series with the three-phase windings are equal, the number of the filter capacitors and the resistors which are connected in parallel between any two phases 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.

Further, the height H2 of the inductor core is smaller than the height H1 of the inductor core, i.e., H2< H1.

Further, the length W2 of the inductor core is smaller than the length W1 of the teeth, i.e., W2< W1.

Further, the inductive reactance L of any one of the induction coils satisfies:

wherein U is a power supply voltage, P_NK is a constant for the output power of the motor.

Further, the constant K satisfies: k is more than or equal to 0.2 and less than or equal to 0.6.

Further, the inductance cores are uniformly arranged along the circumferential direction of the stator.

The invention discloses a permanent magnet synchronous servo motor in a second aspect, which comprises the stator in the first aspect.

Has the advantages that: the harmonic wave reducing circuit is connected to the input end of the three-phase winding of the motor, and can filter out higher harmonics and lower harmonics of the outlet end of the controller, so that the magnetic field of the motor is not influenced by the harmonics, the uniformity of the magnetic field of the motor 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.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings. The drawings described below are merely exemplary embodiments of the present disclosure, and other drawings may be derived by those skilled in the art without inventive effort.

FIG. 1 shows an isometric view of a stator of embodiment 1;

FIG. 2 is a front view of a stator of embodiment 1;

FIG. 3 is a side view of a stator of embodiment 1;

FIG. 4 is a schematic diagram showing the connection of a harmonic circuit to a three-phase winding in embodiment 1;

FIG. 5a shows the structure of a first magnetism isolating groove in embodiment 1;

FIG. 5b shows the structure of a second magnetism isolating groove in embodiment 1;

FIG. 5c shows the structure of a third magnetism isolating groove in embodiment 1;

FIG. 5d shows the structure of a fourth magnetism isolating groove in practical example 1;

fig. 6 shows a schematic diagram of a first harmonic circuit in embodiment 1.

Detailed Description

In order to make the objects, 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 drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, and "a" and "an" generally include at least two, but do not exclude at least one, unless the context clearly dictates otherwise.

It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element.

To further illustrate the technical solution of the present invention, the following specific examples are provided with reference to fig. 1 to 6.

Example 1

In the present embodiment, as shown in fig. 1 to 4, U, V, W three-phase windings are provided on the stator, each phase winding is wound on a tooth portion a of the stator, a harmonic reduction circuit 10 is connected to an input end of the three-phase winding, and the harmonic reduction circuit 10 is used for filtering out higher order and lower order harmonics when the motor is running.

As shown in fig. 4, an inductance coil 11 is connected in series to an input end of each phase of winding, a filter capacitor 12 and a resistor 13 which are connected in parallel are electrically connected between the input ends of any two phases of the winding, and the harmonic reduction circuit 10 is formed by the inductance coil 11 connected in series to each phase of winding and the filter capacitor 12 and the resistor 13 connected in parallel between any two phases of the winding.

Further, as shown in fig. 1 to 3, an inductance core 20 extending along a radial direction of the stator is disposed at a yoke portion of the stator, the number of the inductance cores 20 is 3n, n is an integer greater than or equal to 1, an inductance coil 11 is wound on each inductance core 20, a magnetic isolation slot c is disposed at a position on the stator corresponding to the inductance core 20, and the magnetic isolation slot c is used for blocking the inductance coil 11 and a magnetic path of the winding, preventing the magnetic path of the inductance coil 11 from being coupled with the magnetic path of the winding, and ensuring uniformity of a magnetic field in the stator.

In one embodiment of the present invention, the inductor core 20 is located inside the yoke portion a of the stator and extends along the center of the stator, the inductor core 20 is located inside the tooth slot of the stator, the inductor 11 is provided with magnetic isolation teeth 30 on both sides in the circumferential direction of the stator, and the magnetic isolation teeth 30 are connected to the yoke portion a of the stator. The inductor core 20 is located inside the yoke portion a of the stator, the structure of the magnetic isolation slot c may be multiple, and this embodiment exemplifies three arrangement manners of the magnetic isolation slot c, as shown in fig. 5a, the magnetic isolation slot c is a long slot, one of the long slots is perpendicular to the extending direction of the inductor core 20, and is arranged at the yoke portion b of the stator, two short and long slots with a length shorter than that of the long slot are further distributed at two sides of the long slot, the positions of the short and long slots correspond to the positions of the magnetic isolation teeth 30, and the extending direction of the end long slot is the same as the direction of the magnetic isolation teeth 30. The structure of the magnetism isolating groove c can also be the structure of fig. 5b, the magnetism isolating groove c is a waist-shaped groove and extends along the circumferential direction of the stator, the yoke part a of the stator is arranged, and the position of the magnetism isolating groove c corresponds to the position of the magnetism isolating tooth 30. As shown in fig. 5c, the magnetic isolation slots c are formed at the end of the inductor core 20 with a notch, the length direction of the notch is the same as the extending direction of the inductor core 20, and three circular magnetic isolation slots c are arranged at the fixed yoke part, wherein one circular magnetic isolation slot c is positioned at the yoke part a of the stator and corresponds to the position of the inductor core 20, and the other two circular magnetic isolation slots c are distributed at two sides of the one circular magnetic isolation slot c and correspond to the positions of the coil slots. The shape of the magnetism isolating groove c may be other shapes such as a direction, which is not exemplified here.

In one embodiment, the outer circumference of the yoke portion of the stator is provided with 3n sets of gaps g extending along the radial direction of the stator, n is an integer greater than or equal to 1, the number of the gaps g in each set is two, and the yoke portion of the stator forms the inductor core 20 between each set of the gaps g. The structure of the magnetic isolation groove c on the inductor core 20 is shown in fig. 5d, the magnetic isolation groove c is two waist-shaped grooves, which are symmetrical relative to the inductor core 20, the waist-shaped grooves are bent towards the direction of the gap, each waist-shaped groove corresponds to the position of each gap g, the extending length of each waist-shaped groove is greater than the maximum width of the gap g, the magnetic circuit of the inductor core 20 can be blocked, the magnetic circuit coupling with the winding is prevented, and the inductor core 20 is arranged on the opposite side of the tooth part of the stator, so that the magnetic isolation teeth 30 are not arranged.

The magnetic isolation teeth 30 are connected to the yoke portion b of the stator, and a coil slot for accommodating the inductor coil 11 is formed between each of the two magnetic isolation teeth 30 and the inductor core 20. The inductance coil 11 has the characteristic of isolating alternating current and direct current, so that higher harmonics at the output end of the controller can be filtered, and meanwhile, the capacitor electrically connected between any two phase windings can play a role in filtering low harmonics and can filter low harmonics at the output end of the controller.

Further, the number and the inductive reactance of the inductance coils 11 respectively connected in series with the three-phase windings are equal, the number of the filter capacitors 12 and the 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 that the magnetic circuit distribution of the stator is uniform. The number of the filter capacitors 12 connected in parallel between the U-phase winding and the V-phase winding can be 1, and 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 are also equal to the number of the filter capacitors 12 connected between the U-phase winding and the V-phase winding, and the resistance values are also equal to each other, and the number of the resistors between the two phases and the two phases of windings is also equal to each other and the resistance values are also equal to each other. As shown in fig. 6, three inductors 11 (L1, L2, and L3 in the harmonic reduction circuit 10 are connected in parallel, two capacitors (C1 and C2 in the drawing, C3 and C4 in the drawing, and C5 and C6) and one resistor (R1 to R3 in the drawing) are connected in parallel between two adjacent inductors 11, and the harmonic reduction circuit 10 may also adopt the connection manner shown in fig. 4, that is, two capacitors (C1 to C3 in the drawing) and one resistor (R1 to R3 in the drawing) are connected in parallel between two adjacent inductors 11.

In this embodiment, the three-phase winding on the stator may have a plurality of connection forms, and the specific connection form is the same as that in the prior art, and is not described herein again.

To further avoid the influence of the magnetic field of the inductor core on the internal magnetic field of the stator, the height H2 of the inductor core is smaller than the height H1 of the inductor core, i.e., H2< H1. The length W2 of the inductor core is smaller than the length W1 of the teeth, i.e., W2< W1.

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

The constant K satisfies: k is more than or equal to 0.2 and less than or equal to 0.6, and higher harmonics can be filtered out through the above formula and the limitation of the constant K.

The inductance cores are uniformly arranged along the circumferential direction of the stator.

Example 2

The invention provides a permanent magnet synchronous servo motor which comprises a stator in embodiment 1.

Exemplary embodiments of the present disclosure are specifically illustrated and described above. It is to be understood that the present disclosure is not limited to the precise arrangements, instrumentalities, or instrumentalities described herein; on the contrary, the disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. a stator, described stator is provided with U, V, W three-phase winding, it is characterized in that, described three-phase winding input end is connected with harmonic reduction circuit, and described harmonic reduction circuit is used for filtering out Higher and lower harmonics when the motor is running.

2. A kind of stator as claimed in claim 1, it is characterized in that, inductance coil is connected in series with the input end of each phase winding, and parallel filter capacitor and resistance are electrically connected between the input ends of any two-phase described winding, and each phase winding is connected with each other. The inductance coils connected in series with the windings of the phases and the filter capacitors and resistors connected in parallel between the windings of any two phases form the harmonic reduction circuit.

3 . The stator according to claim 2 , wherein the yoke of the stator is provided with inductive iron cores extending along the radial direction of the stator, and the number of the inductive iron cores is 3n, n is an integer greater than or equal to 1, each inductance core is wound with an inductance coil, and a magnetic isolation slot is provided on the stator at a position corresponding to the inductance iron core, and the magnetic isolation slot is used to block the inductance coil magnetic circuit with the windings.

4 . The stator of claim 3 , wherein 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 on the stator. 5 . In the tooth slots 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.

5 . The stator according to claim 3 , wherein the outer circumference of the yoke of the stator is provided with 3n groups of notches extending along the radial direction of the stator, and n is an integer greater than or equal to 1, 6 . The number of each group of notches is two, and the yoke of the stator forms the inductor core between each group of the notches.

6 . The stator according to claim 3 , wherein the number and inductive reactance of the inductive coils connected in series with the three-phase windings are equal, and the filter capacitors connected in parallel between any two phases and the two-phase windings are equal. 7 . If the number of resistors is equal, the capacitance values of the filter capacitors are equal, and the resistance values of the resistors are also equal.

7 . The stator according to claim 3 , wherein the height H2 of the inductor iron core is smaller than the height of the inductor iron core H1 , that is, H2 < H1 . 8 .

8 . The stator according to claim 3 , wherein the length W2 of the inductor core is smaller than the length W1 of the teeth, that is, W2<W1 . 9 .

9. The stator according to claim 3-6, wherein the inductive reactance L of any one of the inductive coils satisfies:

Among them, U is the power supply voltage, P _N is the motor output power, and K is a constant.

10. The stator according to claim 9, wherein the constant K satisfies: 0.2≤K≤0.6.

11 . The stator according to claim 3 , wherein the inductor cores are evenly arranged along the circumferential direction of the stator. 12 .

12. A permanent magnet synchronous servo motor, characterized in that it comprises a stator according to any one of claims 1-11.