CN112701874B - Low-torque ripple synchronous reluctance linear motor and rotor manufacturing method - Google Patents
Low-torque ripple synchronous reluctance linear motor and rotor manufacturing method Download PDFInfo
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Abstract
The invention discloses a low-torque pulsation synchronous reluctance linear motor and a manufacturing method of a rotor, wherein the motor comprises a stator and a rotor, the stator is provided with a plurality of grooves distributed along the length direction of the stator, and windings are wound in the grooves; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the direction of the stator. The invention adopts the internal magnetic barrier of the trapezoidal hollowed-out groove structure, and can play the best role of magnetic concentration, thereby improving the air gap flux density from rectangular wave to stepped wave, improving the fundamental wave amplitude of the air gap flux density, reducing the harmonic distortion rate, and achieving the purposes of reducing torque pulsation and improving the performance of the synchronous reluctance linear motor.
Description
Technical Field
The invention relates to the technical field of linear motors, in particular to a synchronous reluctance type direct motor, and specifically relates to a low-torque pulsation synchronous reluctance linear motor and a manufacturing method of a rotor thereof.
Background
At present, in equipment in many application places, a synchronous reluctance linear motor has the advantages of low cost and high reliability. A common synchronous reluctance linear motor is provided with a connected magnetic bridge. The motor silicon steel sheet and each magnetic barrier are connected with each other. Although the structure keeps the position relation and enhances the mechanical strength, the connected magnetic bridges at the connecting end part generate magnetic leakage, so that the thrust performance and the driving efficiency of the motor cannot be improved. The torque ripple is large and the vibration noise is large.
The existing synchronous reluctance motor utilizes reluctance torque, the salient polarity of the motor is strong, the torque pulsation of the motor is large, a plurality of grooves are formed in the rotor, the structure of the rotor is relatively complex, the torque pulsation is difficult to optimize, and the motor is large in vibration and high in noise due to excessive torque pulsation.
Disclosure of Invention
The invention aims to solve the technical problems of large torque ripple, large motor vibration and high noise of the conventional synchronous reluctance motor, and provides a low-torque ripple synchronous reluctance linear motor without a connected magnetic bridge.
In order to solve the technical problems, the invention adopts the following technical scheme: a low-torque pulse synchronous reluctance linear motor comprises a stator and a rotor, wherein a plurality of grooves distributed along the length direction of the stator are formed in the stator, and windings are wound in the grooves; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the direction of the stator.
In a synchronous reluctance linear motor, a non-sine distributed air gap magnetic field can cause a large amount of harmonic waves, easily cause torque pulsation and increase the loss of the motor. The invention provides a motor with a novel structure of a rotor with magnetic barriers, and the internal magnetic barriers of a trapezoidal hollowed-out groove structure are adopted, so that the optimal magnetic gathering effect can be achieved, the air gap flux density is improved from rectangular waves to stepped waves, the fundamental wave amplitude of the air gap flux density is improved, the harmonic distortion rate is reduced, and the purposes of reducing torque pulsation and improving the performance of a synchronous reluctance linear motor are achieved.
As a refinement of the invention, the set of magnetic barriers comprises one or more internal magnetic barriers. Two to a plurality of internal magnetic barriers are arranged at intervals along the height direction of the rotor, so that a two to a multilayer structure is formed. Preferably, the magnetic barrier group comprises three inner magnetic barriers.
As a further improvement of the invention, a top center magnetic barrier is also arranged above the upper magnetic barrier. The top central magnetic barrier is in a ladder-shaped structure.
As a still further improvement of the present invention, the magnetic barrier groups are uniformly distributed along the length direction of the mover, and each magnetic barrier group and its corresponding mover part form a mover unit. The rotor units can be independent from each other or can be integrally manufactured. The specific shape of the magnetic barrier is determined by control variables such as parameters of the trapezoidal hollow groove, and the optimal performance point can be found by changing the size of each control variable. The height of each layer of magnetic barrier can be the same or different. The heights of all parts of the same magnetic barrier can be the same or different.
As a still further improvement of the present invention, the relationship between the length L of each mover unit and the height H of the mover unit is: h is more than or equal to 0.3 and less than or equal to 0.5.
As a still further improvement of the present invention, the relationship between the distance T from the bottom edge of the bottom layer magnetic barrier to the bottom edge of the mover and the height H of the mover unit is: t is not less than 0.075H and not more than 0.125H.
As a further improvement of the invention, the relation between the distance S between the outer side of the top of the bottom layer magnetic barrier and the left side of the rotor and the length L of the rotor unit is as follows: s is not less than 0.03 and not more than 0.05.
As a still further development of the invention, the opening width of the top of the inner magnetic barrier is between 0.03 and 0.06 × L, where L is the mover element length.
As a still further refinement of the invention, the height of the inner barrier bottom groove is between 0.075 × H and 0.125 × H, where H is the mover unit height.
As a still further improvement of the present invention, the spacing between adjacent barrier bottom grooves is between 0.075 × H and 0.125 × H, where H is the mover height.
As a further improvement of the present invention, the magnetic barrier may be a hollow trapezoidal hollow groove, or a non-magnetic material may be filled in the trapezoidal hollow groove. Preferably, the non-magnetic conductive material is resin. Because the magnetic barriers are arranged in the rotor, the rotor is divided into a multilayer structure, and in order to facilitate processing, the end parts of the magnetic barriers need to be connected through magnetic bridges, but power factors are reduced. After the magnetic barriers are filled with the non-magnetic materials, the magnetic barriers are wrapped by the non-magnetic materials, and the main magnetic bridge made of silicon steel sheets is fixed to form a whole. There is no magnetic bridge between each magnetic barrier, which can improve the power factor and efficiency of the motor.
The invention also provides a method for manufacturing a rotor of the low-torque ripple synchronous reluctance linear motor, which is characterized by comprising the following steps of: (1) firstly, manufacturing silicon steel sheets into a structure with connected magnetic bridges, wherein a plurality of groups of magnetic barrier groups distributed along the length direction of a rotor are arranged on the silicon steel sheets, and each magnetic barrier group comprises at least one internal magnetic barrier; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; (2) then laminating a plurality of silicon steel sheets together; (3) then, non-magnetic materials are cast into the trapezoidal hollow-out groove at the position of the inner magnetic barrier, and the non-magnetic materials and the main magnetic bridge made of silicon steel sheets form a whole after being solidified; (4) finally, the connected magnetic bridges at the ends are cut off.
The invention also provides another method for manufacturing the rotor of the low-torque pulsation synchronous reluctance linear motor, which is characterized by comprising the following steps of: (1) firstly, manufacturing a silicon steel sheet into a structure with a connected magnetic bridge, and arranging at least one internal magnetic barrier on the structure; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; (2) then laminating a plurality of silicon steel sheets together; (3) then, non-magnetic materials are cast into the trapezoidal hollow-out groove at the position of the inner magnetic barrier, and the non-magnetic materials and the main magnetic bridge made of silicon steel sheets become a rotor unit after being solidified; (4) cutting off the connected magnetic bridge at the end part; (5) and bonding the plurality of rotor units along the length direction to form a complete rotor.
Drawings
The invention is further illustrated by the following examples in conjunction with the drawings.
Fig. 1 is a schematic structural diagram of a low-torque ripple synchronous reluctance linear motor according to the present invention.
Fig. 2 is a schematic structural diagram of a mover unit according to the present invention.
Fig. 3 is a schematic diagram illustrating a control change of the mover unit according to the present invention.
Fig. 4 is a schematic structural diagram of another embodiment of a mover unit of the present invention.
In the figure, 1-stator, 2-mover, 101-stator groove, 201-internal magnetic barrier, 202-non-magnetic material, 203-bottom groove, 204-left groove, 205-right groove, 206-mover unit, 207-bottom magnetic barrier, 208-middle magnetic barrier, 209-upper magnetic barrier, 210-top center magnetic barrier.
Detailed Description
Referring to fig. 1, the low-torque ripple synchronous reluctance linear motor of the present invention includes a stator 1 and a mover 2, wherein the stator 1 is provided with a plurality of grooves 101 distributed along the length direction of the stator, and the grooves 101 are wound with windings. The mover 2 is provided with a plurality of groups of magnetic barrier groups which are uniformly distributed along the length direction of the mover, and each magnetic barrier group comprises at least one internal magnetic barrier 201.
Each magnetic barrier group forms one mover unit 206 with its corresponding mover portion. Each of the mover units 206 may be independent from each other or may be integrally formed. The specific shape of the internal magnetic barrier is determined by control variables such as parameters of the trapezoidal hollow groove, and the optimal performance point can be found by changing the size of each control variable. The height of each layer of magnetic barrier can be the same or different. The heights of all parts of the same inner magnetic barrier can be the same or different.
Referring to fig. 2, the mover unit 206 is provided with four magnetic barriers including an inner magnetic barrier composed of a bottom magnetic barrier 207, an intermediate magnetic barrier 208, and an upper magnetic barrier 209, and a top center magnetic barrier 210. And the magnetic barriers are arranged at intervals along the height direction of the rotor. The bottom layer magnetic barrier 207, the middle layer magnetic barrier 208 and the upper layer magnetic barrier 209 are in a trapezoid hollow groove-shaped structure and comprise a bottom groove 203, a left groove 204 and a right groove 205 which are parallel to the length direction of the rotor, and the side grooves 204 and 205 on the two sides are opened from the bottom groove to the direction of the stator 1. The top center barrier 210 has a ladder-shaped configuration.
In a synchronous reluctance linear motor, a non-sine distributed air gap magnetic field can cause a large amount of harmonic waves, easily cause torque pulsation and increase the loss of the motor. The invention provides a motor with a novel structure of a rotor with a magnetic barrier, and the magnetic barrier with a trapezoidal hollowed-out groove structure is adopted, so that the optimal magnetic gathering effect can be achieved, the air gap flux density is improved from rectangular waves to stepped waves, the amplitude of the fundamental wave of the air gap flux density is improved, the harmonic distortion rate is reduced, and the purposes of reducing torque pulsation and improving the performance of a synchronous reluctance linear motor are achieved.
Referring to fig. 3, the present invention achieves the best performance point by changing the proper ratio of the magnitudes of the following control variables.
The relationship between the mover length L and the mover height H is: h is more than or equal to 0.3 and less than or equal to 0.5.
The relation between the distance T from the bottom edge of the bottom layer magnetic barrier to the bottom edge of the rotor and the height H of the rotor is as follows: t is not less than 0.075H and not more than 0.125H.
The distance S between the outer side of the top of the bottom layer magnetic barrier and the left side of the rotor and the length L of the rotor are in the following relation: s is not less than 0.03 and not more than 0.05.
The relation between the left opening width M1 of the top of the bottom layer magnetic barrier and the length L of the rotor is as follows: 0.03L M1L 0.06L.
The relation between the left opening width M2 at the top of the middle layer magnetic barrier and the length L of the rotor is as follows: 0.03L M2L 0.06L.
The relation between the left opening width M3 of the top of the upper layer magnetic barrier and the length L of the mover is as follows: 0.03L M3L 0.06L.
The relation between the width N1 of the right opening at the top of the bottom magnetic barrier and the length L of the rotor is as follows: n1 is not less than 0.03 and not more than 0.06.
The relation between the width N2 of the right opening at the top of the middle layer magnetic barrier and the length L of the rotor is as follows: n2 is not less than 0.03 and not more than 0.06.
The relation between the width N3 of the right opening at the top of the upper magnetic barrier and the length L of the rotor is as follows: n3 is not less than 0.03 and not more than 0.06.
The relation between the height A1 of the bottom groove of the bottom magnetic barrier and the height H of the rotor is as follows: 0.075H is less than or equal to A1 is less than or equal to 0.125H.
The relation between the height A2 of the middle layer magnetic barrier bottom groove and the height H of the mover is as follows: 0.075H is less than or equal to A2 is less than or equal to 0.125H.
The relation between the height A3 of the bottom groove of the upper magnetic barrier and the height H of the mover is as follows: 0.075H is less than or equal to A3 is less than or equal to 0.125H.
The relation between the distance B1 between the bottom slots of the bottom layer magnetic barriers and the middle layer magnetic barriers and the height H of the rotor is as follows: 0.075H B2H 0.125H.
The relation between the interval B2 between the middle layer magnetic barrier and the upper layer bottom groove and the height H of the mover is as follows: 0.075H-B2-0.125H.
The relation between the interval B3 between the upper layer magnetic barrier and the bottom surface of the top center magnetic barrier and the height H of the rotor is as follows: 0.075H B3H 0.125H.
In the above embodiments, the magnetic barrier is a hollow trapezoidal hollow groove, and no filling material is in the groove.
Referring to fig. 4, another embodiment of a low torque ripple synchronous reluctance linear motor of the present invention. In this embodiment, in addition to the embodiment of fig. 2, the trapezoidal hollow-out groove and the top trapezoidal groove are filled with a non-magnetic material 202. Preferably, the non-magnetic conductive material is resin. Because the magnetic barriers are arranged in the rotor, the rotor is divided into a multilayer structure, and in order to facilitate processing, the end parts of the magnetic barriers need to be connected through magnetic bridges, but power factors are reduced. When the magnetic bridge is filled with the non-magnetic conductive material, the magnetic barriers are wrapped by the non-magnetic conductive material, and the main magnetic bridge made of silicon steel sheets is fixed to form a whole. And no connected magnetic bridge exists between the magnetic barriers, so that the power factor and the efficiency of the motor can be improved.
The invention also provides a method for manufacturing a rotor of the low-torque ripple synchronous reluctance linear motor, which is characterized by comprising the following steps of: (1) firstly, manufacturing silicon steel sheets into a structure with connected magnetic bridges, wherein a plurality of groups of magnetic barrier groups distributed along the length direction of a rotor are arranged on the silicon steel sheets, and each magnetic barrier group comprises at least one internal magnetic barrier; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; (2) then laminating a plurality of silicon steel sheets together; (3) then, non-magnetic materials are cast into the trapezoidal hollow-out groove at the position of the inner magnetic barrier, and the non-magnetic materials and the main magnetic bridge made of silicon steel sheets form a whole after being solidified; (4) finally, the connected magnetic bridges at the ends are cut off.
The invention also provides another method for manufacturing the rotor of the low-torque pulsation synchronous reluctance linear motor, which is characterized by comprising the following steps of: (1) firstly, manufacturing a silicon steel sheet into a structure with a connected magnetic bridge, and arranging at least one internal magnetic barrier on the structure; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; (2) then laminating a plurality of silicon steel sheets together; (3) then, non-magnetic materials are cast into the trapezoidal hollow-out groove at the position of the inner magnetic barrier, and the non-magnetic materials and the main magnetic bridge made of silicon steel sheets become a rotor unit after being solidified; (4) cutting off the connected magnetic bridge at the end part; (5) and bonding the plurality of rotor units along the length direction to form a complete rotor.
It should be understood that: the above-mentioned embodiments are merely illustrative, not restrictive, of the present invention, and any invention which does not depart from the spirit and scope of the present invention shall fall within the protection scope of the present invention.
Claims (5)
1. A low-torque pulse synchronous reluctance linear motor comprises a stator and a rotor, wherein a plurality of grooves distributed along the length direction of the stator are formed in the stator, and windings are wound in the grooves; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; the magnetic barrier group comprises one to more internal magnetic barriers; two to a plurality of internal magnetic barriers are arranged at intervals along the height direction of the rotor, so that a two to multilayer structure is formed; a top central magnetic barrier is also arranged above the upper layer magnetic barrier, and the top central magnetic barrier is in a trapezoidal structure; the magnetic barrier groups are uniformly distributed along the length direction of the rotor, and each magnetic barrier group and the corresponding rotor part form a rotor unit; the relationship between the length L of each mover unit and the height H of the mover unit is: h is not less than 0.3 and not more than 0.5; the relationship between the distance T from the bottom edge of the bottom layer magnetic barrier to the bottom edge of the rotor and the height H of the rotor unit is as follows: t is more than or equal to 0.075 and less than or equal to 0.125 and H; the distance S between the outer side of the top of the bottom layer magnetic barrier and the left side of the rotor and the length L of the rotor unit are in the following relation: s is not less than 0.03 and not more than 0.05; the opening width of the top of the inner magnetic barrier is between 0.03L and 0.06L, wherein L is the length of the rotor unit; the height of the inner magnetic barrier bottom groove is between 0.075H and 0.125H, wherein H is the height of the rotor unit; the interval between the adjacent magnetic barrier bottom grooves is between 0.075H and 0.125H, wherein H is the height of the rotor.
2. The linear motor of claim 1, wherein the trapezoidal hollow-out slots are filled with a non-magnetic material.
3. The linear motor of claim 1, wherein said top central barrier is filled with a non-magnetically conductive material.
4. A method of manufacturing a mover of a low torque ripple synchronous reluctance linear motor as claimed in claim 1, comprising the steps of: (1) firstly, manufacturing silicon steel sheets into a structure with a connected magnetic bridge, wherein a plurality of groups of magnetic barrier groups distributed along the length direction of a rotor are arranged on the silicon steel sheets, and each magnetic barrier group comprises at least one internal magnetic barrier; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; (2) then laminating a plurality of silicon steel sheets together; (3) then, non-magnetic materials are cast into the trapezoidal hollow-out groove at the position of the inner magnetic barrier, and the non-magnetic materials and the main magnetic bridge made of silicon steel sheets form a whole after being solidified; (4) finally, the connected magnetic bridges at the ends are cut off.
5. A method of manufacturing a mover of a low torque ripple synchronous reluctance linear motor as claimed in claim 1, comprising the steps of: (1) firstly, manufacturing a silicon steel sheet into a structure with a connected magnetic bridge, and arranging at least one internal magnetic barrier on the structure; the internal magnetic barrier is in a trapezoid hollow groove-shaped structure and comprises a bottom groove parallel to the length direction of the rotor and two side grooves, and the two side grooves are opened from the bottom groove to the stator direction; (2) then laminating a plurality of silicon steel sheets together; (3) then, non-magnetic materials are cast into the trapezoidal hollow-out groove at the position of the inner magnetic barrier, and the non-magnetic materials and the main magnetic bridge made of silicon steel sheets become a rotor unit after being solidified; (4) cutting off the connected magnetic bridge at the end part; (5) and bonding the plurality of rotor units along the length direction to form a complete rotor.
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CN106100500B (en) * | 2016-08-24 | 2018-12-07 | 河北工业大学 | A kind of synchronous magnetic resistance motor that can effectively reduce motor torque ripple |
CN108336841A (en) * | 2018-05-03 | 2018-07-27 | 杭州瑞拉腾电气科技有限公司 | A kind of rotor for synchronous magnetic resistance motor |
CN109951049A (en) * | 2019-04-03 | 2019-06-28 | 诺丁汉(余姚)智能电气化研究院有限公司 | Synchronous reluctance formula linear motor |
CN110048530B (en) * | 2019-04-22 | 2020-09-25 | 大连理工大学 | Rotor structure of permanent magnet auxiliary synchronous reluctance motor and design method |
CN110994825B (en) * | 2019-12-09 | 2021-05-07 | 珠海格力电器股份有限公司 | Motor rotor and manufacturing method thereof, reluctance motor and electric automobile |
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