Rotor structure and electric machine having the same

Abstract

The application provides a rotor structure and a motor with the same. The rotor structure comprises a rotor core, wherein a magnetic steel slot is arranged on the rotor core; the number of the magnetic steel slots is at least two, and the at least two magnetic steel slots are arranged in sequence around the circumference of the rotor core; a permanent magnet is arranged in each magnetic steel slot; a guide slot is arranged between two adjacent magnetic steel slots, and a guide soft magnet is arranged in the guide slot; among two adjacent permanent magnets, the guide soft magnet can guide the magnetic force line of one of the permanent magnets to the other permanent magnet to form a closed magnetic force line; and the rotor core is made of a non-guide soft magnet. According to the rotor structure and the motor with the same, the magnetic field distortion can be improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electric machines, and particularly relates to a rotor structure and an electric machine with the same. BACKGROUND

[0002] At present, in a conventional permanent magnet synchronous motor, there is inevitably magnetic leakage, and the magnetic field distribution in the rotor is distorted, which is particularly serious when the thickness of the rotor yoke is large. The distorted rotor magnetic field causes magnetic field imbalance, which has a certain influence on the performance of the motor.

[0003] Therefore, how to provide a rotor structure capable of improving magnetic field distortion and an electric machine with the same has become a problem that those skilled in the art urgently need to solve. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to provide a rotor structure and an electric machine with the same, which can improve magnetic field distortion.

[0005] In order to solve the above problems, the present application provides a rotor structure, comprising: a rotor core, a magnetic steel slot is formed on the rotor core; the number of magnetic steel slots is set to at least two, and the at least two magnetic steel slots are arranged in sequence around the circumference of the rotor core; a permanent magnet is arranged in each magnetic steel slot; a guide slot is arranged between the two adjacent magnetic steel slots, and a guide soft magnet is arranged in the guide slot; among the two adjacent permanent magnets, the guide soft magnet can guide the magnetic force line of one of the permanent magnets to the other permanent magnet to form a closed magnetic force line; the rotor core is made of a guide soft magnet.

[0006] Further, a magnetic isolation structure is arranged on the inner circumferential side of the guide slot.

[0007] Further, on the cross section of the rotor core, the shape of the magnetic isolation structure is circular, and the center of the circle is located on the symmetry line of the two adjacent magnetic steel slots.

[0008] Further, a through hole is formed on the rotor core, and the through hole forms the magnetic isolation structure; the rotor structure further comprises a fastener, and the fastener can penetrate through the through hole to fix the rotor core.

[0009] Further, on the cross section of the rotor core, the shape of the guide soft magnet is trapezoidal, and the two waists of the trapezoidal shape are respectively parallel to the extension direction of the two adjacent magnetic steel slots.

[0010] Further, the minimum distance between the magnetic steel slot and the central axis of the rotor core is c; when the rotor core has a through hole, the distance between the central axis of the through hole and the central axis of the rotor core is k; when the shape of the guide soft magnet on the cross section of the rotor core is a trapezoid, the upper base length of the trapezoid is a; the lower base length of the trapezoid is b; the waist length of the trapezoid is h; the pole number of the rotor structure is P; the outer diameter of the rotor core is r2; the width of the permanent magnet is hm; the length of a single permanent magnet in the magnetic steel slot is bm; the pole number of the rotor structure is P; P refers to the pole number, and the structure like a "V" formed by two adjacent magnetic steels is referred to as a pole, for example, the pole number of the motor in the figure is 8 poles.

[0011] wherein,

[0012] And / or, the cross-sectional radius of the through hole is r3; the rotor core has a shaft hole; the radius of the shaft hole is r1; wherein, r3=1 / 8*(r1-r2); and / or, the minimum distance between the through hole and the shaft hole is 2r3.

[0013] Further, the waist of the trapezoid has a gap with the corresponding magnetic steel slot, and the gap width is d; wherein, d=0.5hm.

[0014] Further, the waist length of the trapezoid is h; the length of a single permanent magnet in the magnetic steel slot is bm; wherein h=0.54bm.

[0015] Further, the magnetic steel slot is a v-shaped magnetic steel slot, and half of the included angle of the v-shaped magnetic steel slot is angle; the upper base length of the trapezoid is a;

[0016] Further, the lower base length of the trapezoid is b;

[0017] According to still another aspect of the present application, a motor is provided, comprising a rotor structure as described above.

[0018] The rotor structure and the motor having the same are provided by the present application. The present application can improve the magnetic field distortion. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 FIG. 1 is a structural schematic diagram of a motor in an embodiment of the present application;

[0020] Figure 2 FIG. 2 is a schematic diagram of magnetic lines of force in an embodiment of the present application;

[0021] Figure 3 FIG. 3 is a structural schematic diagram of a rotor core in an embodiment of the present application;

[0022] Figure 4A structure diagram of a rotor core in the embodiments of the present application;

[0023] Figure 5 A magnetic force line diagram in the prior art.

[0024] 1, rotor core; 11, shaft hole; 12, magnetic isolation structure; 2, magnetic steel slot; 3, permanent magnet; 31, first permanent magnet; 32, second permanent magnet; 4, guide slot; 41, guide soft magnet; 5, stator structure; 51, stator yoke; 52, stator tooth. DETAILED DESCRIPTION

[0025] For reference Figures 1-4 As shown in the figure, a rotor structure comprises: a rotor core 1, the rotor core 1 is provided with a magnetic steel slot 2; the number of magnetic steel slots 2 is at least two, and the at least two magnetic steel slots 2 are arranged in sequence around the circumference of the rotor core 1; each magnetic steel slot 2 is provided with a permanent magnet 3; a guide slot 4 is arranged between the adjacent two magnetic steel slots 2, and the guide slot 4 is provided with a guide soft magnet 41; among the adjacent two permanent magnets 3, the guide soft magnet 41 can guide the magnetic force line of one of the permanent magnets 3 to the other permanent magnet 3 to form a closed magnetic force line; the rotor core 1 is made of non-oriented silicon steel sheet; the guide soft magnet 41 is made of oriented silicon steel sheet, and the rotor core 1 is made of non-oriented silicon steel sheet; the oriented silicon steel sheet of the present application can guide the magnetic force line of one of the permanent magnets 3 to the other permanent magnet 3 to form a closed magnetic force line, which can affect and comb the distribution of the magnetic field under the adjacent magnetic poles, improve the magnetic field distortion, and at the same time reduce the degree of magnetic field distortion and improve the unbalanced situation of the magnetic field. The effect of improving the magnetic field distortion of the present application can be known by comparing Figure 2 and Figure 5 Figure 2 to improve the effect.

[0026] As Figure 5 shown, it is a common permanent magnet synchronous motor using "V" type permanent magnet 3, and the motor is 48 slot 8 pole, the slot number refers to the number of slots between the two stator teeth, and the pole number refers to the number of "V" type permanent magnet 3; Figure Three is 1 / 4 model of the whole motor, in the model, the magnetic path of the magnetic flux generated by the second permanent magnet 32 is divided into several kinds, including A1, A2, A3, leakage magnetic path, wherein A1 path is the shortest, and A2, A3 is longer, and A2, A3 causes the unbalance of the magnetic field, in order to ensure the high performance of the motor, the proportion of the magnetic field of the three kinds of magnetic paths A2, A3 and leakage magnetic path should be avoided as far as possible. The "V" type permanent magnet 3 comprises a first permanent magnet 31 and a second permanent magnet 32.

[0027] And the technical scheme of the present application is adopted, as Figure 2 ​As shown, the silicon steel sheet can guide the magnetic force lines of one of the permanent magnets 3 to the other permanent magnet 3 to form closed magnetic force lines, effectively avoiding the magnetic paths of A2, A3 and leakage magnetic paths, so that the magnetic path generated by the second permanent magnet 32 all passes through the silicon steel sheet, shortens the magnetic path, improves the magnetic field distortion, and reduces the degree of magnetic field distortion, and improves the imbalance of the magnetic field.

[0028] The application also discloses some embodiments, wherein the inner circumferential side of the guide groove 4 is provided with a magnetic isolation structure 12. Because the magnetic permeability of the magnetic isolation structure 12 is low, the magnetic field above the through hole is preferentially passed through the inside of the oriented soft magnetic body, so that the magnetic field distortion can be improved, the degree of magnetic field distortion is reduced, and the imbalance of the magnetic field is improved.

[0029] The application also discloses some embodiments, wherein the shape of the magnetic isolation structure 12 on the cross section of the rotor core 1 is circular, and the center of the circle is located on the symmetry line between the two adjacent magnetic steel grooves 2.

[0030] The application also discloses some embodiments, wherein the rotor core 1 is provided with a through hole, and the through hole forms the magnetic isolation structure 12; and the rotor structure further comprises a fastener which can penetrate through the through hole to fix the rotor core 1.

[0031] On the one hand, the through hole can cooperate with the fastener to fix the rotor core 1, and on the other hand, the hole is full of air, and the magnetic permeability of the air is similar to that of the permanent magnet 3 and far less than that of the oriented soft magnetic body 41. In actual operation of the motor, the air in the through hole has low magnetic permeability and blocks the magnetic field, and the magnetic field above the through hole preferentially passes through the inside of the oriented soft magnetic body 41, so that the actual magnetic field distribution is as shown in the figure. Figure 2 As shown, in the adjacent magnetic poles, the path of the magnetic flux of the permanent magnet 3 is permanent magnet 3-rotor lamination- oriented soft magnetic body 41-rotor lamination-adjacent magnetic pole permanent magnet 3, and then forms a loop through the air gap between the stator and the rotor, so that the content of the magnetic field corresponding to A2 and A3 is reduced, the degree of magnetic field distortion is reduced, and the imbalance in the rotor magnetic field is improved.

[0032] The application also discloses some embodiments, wherein the shape of the oriented soft magnetic body 41 on the cross section of the rotor core 1 is trapezoidal, and the two waists of the trapezoid are parallel to the extension directions of the two adjacent magnetic steel grooves 2. The upper base and the lower base of the trapezoid can be linear or arc-shaped. As long as the two waists of the trapezoid are parallel to the extension directions of the two adjacent magnetic steel grooves 2, the magnetic force lines of one of the permanent magnets 3 can be guided to the other permanent magnet 3 to form closed magnetic force lines. h is the waist length of the trapezoidal silicon steel sheet, and the size is h=0.54bm. The waist of the trapezoidal silicon steel sheet is parallel to the width corresponding side of the adjacent permanent magnet 3.

[0033] The minimum distance between the magnetic steel slot and the central axis of the rotor core is c; when the rotor core (1) has a through hole, the distance between the central axis of the through hole and the central axis of the rotor core (1) is k; when the guide soft magnet (41) has a trapezoidal shape on the cross section of the rotor core (1), the upper base length of the trapezoid is a; the lower base length of the trapezoid is b; the waist length of the trapezoid is h; the pole number of the rotor structure is P; the outer diameter of the rotor core (1) is r2; the width of the permanent magnet (3) is hm; the length of a single permanent magnet (3) in the magnetic steel slot (2) is bm; the pole number of the rotor structure is P;

[0034] wherein,

[0035] And / or, the cross-sectional radius of the through hole is r3; the rotor core (1) has a shaft hole (11); the radius of the shaft hole (11) is r1; wherein, r3=1 / 8*(r1-r2); and / or, the minimum distance between the through hole and the shaft hole (11) is 2r3.

[0036] The center of the through hole is located on the symmetry line of the adjacent permanent magnets 3 of the adjacent magnetic poles, and the radius r3=1 / 8*(r1-r2), and the distance between the center and the inner circle of the rotor in the radial direction is 2r3. This can make the magnetic isolation effect better, and can ensure the stiffness of the rotor core 1. The through hole and the oriented silicon steel sheet in the trapezoidal shape are both symmetrical about the symmetry line of the adjacent V-shaped permanent magnets 3.

[0037] The application also discloses some embodiments, the width of the permanent magnet 3 is hm; the gap between the waist of the trapezoidal shape and the corresponding magnetic steel slot 2 has a gap width d; wherein, d=0.5hm. The lower base of the guide soft magnet 41 has a recess, which is fixed by matching with the corresponding boss on the rotor punching piece, and the two silicon steel sheets are spliced together.

[0038] The application also discloses some embodiments, the waist length of the trapezoidal shape is h; the length of a single permanent magnet 3 in the magnetic steel slot 2 is bm; wherein h=0.54bm.

[0039] The application also discloses some embodiments, the magnetic steel slot 2 is a v-shaped magnetic steel slot 2, half of the included angle of the v-shaped magnetic steel slot 2 is ; the upper base length of the trapezoidal shape is a; The application can solve the problem of serious magnetic field distortion in the traditional permanent magnet synchronous motor using V-shaped permanent magnets 3, and improve the magnetic field imbalance.

[0040] And need to consider that there is a small air gap between the rotor lamination and the "trapezoidal" guiding soft magnet 41 (i.e. the distance between the guiding slot 4 slot wall and the guiding soft magnet 41), which is generally 0.1mm. Through the above formula, the angle of the angle between the waist of the "trapezoidal" silicon steel sheet and the corresponding side of the width of the adjacent permanent magnet 3 can be increased to facilitate the magnetic flux to pass through the "trapezoidal" guiding soft magnet 41 more smoothly.

[0041] The application also discloses some embodiments, the lower base length of the trapezoid is b; The formula can make the position of the "trapezoidal" guiding soft magnet 41 be determined indirectly by the permanent magnet 3: after the position of the permanent magnet 3 is determined, a point is determined as a reference in the direction perpendicular to the magnetization direction of the permanent magnet 3, taking 0.54bm length from the side close to the shaft hole 11, and the distance between the intersection of the upper base and the waist of the "trapezoidal" permanent magnet 3 and the point in the magnetization direction of the permanent magnet 3 is 0.5hm.

[0042] The application also provides a motor according to another aspect of the application, which comprises a rotor structure, and the rotor structure is the rotor structure described above. The motor is a permanent magnet synchronous motor; the motor further comprises a stator structure 5, and the stator structure 5 further comprises a stator yoke part 51 and a stator tooth part 52.

[0043] Those skilled in the art can easily understand that the above-mentioned advantageous modes can be freely combined and superimposed without conflict.

[0044] The above are only preferred embodiments of the present application, and are not used to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above are only preferred embodiments of the present application, and it should be pointed out that, for ordinary skilled in the art, on the premise of not departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications shall be regarded as the protection scope of the present application.

Claims

1. A rotor structure, characterized by, The rotor core (1) is provided with a magnetic steel slot (2); the number of the magnetic steel slots (2) is at least two, and the at least two magnetic steel slots (2) are arranged in sequence around the circumference of the rotor core (1); each magnetic steel slot (2) is provided with a permanent magnet (3); two adjacent magnetic steel slots (2) are provided with a guide slot (4), and the guide slot (4) is provided with a guide soft magnet (41); among the two adjacent permanent magnets (3), the guide soft magnet (41) can guide the magnetic force line of one of the permanent magnets (3) to the other permanent magnet (3) to form a closed magnetic force line; the rotor core (1) is made of a non-guiding soft magnet; the inner circumferential side of the guide slot (4) is provided with a magnetic isolation structure (12); The rotor core (1) is provided with a through hole, and the through hole forms the magnetic isolation structure (12); The minimum distance between the magnetic steel slot (2) and the center axis of the rotor core (1) is c; the distance between the center axis of the through hole and the center axis of the rotor core (1) is k; on the cross section of the rotor core (1), the shape of the guide soft magnet (41) is a trapezoid, the upper base length of the trapezoid is a; the lower base length of the trapezoid is b; the waist length of the trapezoid is h; the pole number of the rotor structure is P; the outer diameter of the rotor core (1) is r2; the width of the permanent magnet (3) is hm; the length of a single permanent magnet (3) in the magnetic steel slot (2) is bm; the pole number of the rotor structure is P; And / or, the cross-sectional radius of the through hole is r3; the rotor core (1) has a shaft hole (11); the radius of the shaft hole (11) is r1; wherein r3=1 / 8*(r1-r2); and / or, the minimum distance between the through hole and the shaft hole (11) is 2r3. wherein On the cross section of the rotor core (1), the shape of the magnetic isolation structure (12) is a circle, and the center of the circle is located on the symmetry line of the two adjacent magnetic steel slots (2).

2. The rotor structure of claim 1, wherein The rotor structure further comprises a fastener which can penetrate the through hole to fix the rotor core (1).

3. The rotor structure of claim 1, wherein The two waists of the trapezoid are respectively parallel to the extension directions of the two adjacent magnetic steel slots (2).

4. The rotor structure of claim 1, wherein The waist of the trapezoid and the corresponding magnetic steel slot (2) have a gap, and the gap width is d; wherein d=0.5hm.

5. The rotor structure of claim 1, wherein h=0.54bm.

6. The rotor structure of claim 1, wherein The magnetic steel slot (2) is a v-shaped magnetic steel slot (2), and half of the included angle of the v-shaped magnetic steel slot (2) is angle; 7. The rotor structure of claim 1, wherein The motor comprises a rotor structure, and the rotor structure is any one of the rotor structures in claims 1-8.

8. The rotor structure of claim 7, wherein 9. An electric machine characterized by ​

Images