Three-phase self-starting synchronous reluctance motor, compressor

Abstract

The application provides a three-phase self-starting synchronous reluctance motor and a compressor, wherein the three-phase self-starting synchronous reluctance motor comprises a stator assembly and a rotor assembly, the stator assembly comprises a stator core and a stator winding, the stator core is provided with a stator slot, the stator slot comprises a stator large slot and a stator small slot, the outer periphery of the stator core is provided with a stator cut edge at a position corresponding to the stator small slot, and the total number N of the stator cut edges is an even number that can be divided by 3. According to the application, the yoke width of the stator core is more uniform, the phenomenon of excessive saturation of the stator yoke is reduced, the magnetic lines are more uniformly distributed in the stator core, the stator is fully utilized, and the motor efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of motor design technology, specifically relating to a three-phase self-starting synchronous reluctance motor and a compressor. Background Technology

[0002] Self-starting synchronous reluctance motors combine the advantages of asynchronous motors with those of synchronous reluctance motors. They achieve self-starting through asynchronous torque generated by rotor bars, eliminating the need for a frequency converter. Compared to asynchronous motors, they offer constant speed operation, lower rotor losses, and improved efficiency during synchronous operation. Compared to asynchronous-starting permanent magnet synchronous motors, they do not use permanent magnets, resulting in lower costs and eliminating the demagnetization problem associated with permanent magnets. However, the multi-layered magnetic barrier structure of self-starting synchronous reluctance motors leads to low heat dissipation efficiency. To improve heat dissipation, a common method is to chamfer the outer periphery of the stator core, creating stator flow holes to increase airflow area within the motor. However, this chamfering results in uneven stator core yoke width, potentially leading to oversaturation of the stator yoke, uneven magnetic field distribution, underutilization of the stator, and decreased motor efficiency. Summary of the Invention

[0003] Therefore, the present invention provides a three-phase self-starting synchronous reluctance motor and compressor, which can overcome the problem in the related technology that the stator core of the self-starting synchronous reluctance motor has uneven stator core yoke width due to stator truncation, which easily causes stator yoke saturation, resulting in uneven magnetic field distribution, insufficient stator utilization, and reduced motor efficiency.

[0004] To address the aforementioned problems, this invention provides a three-phase self-starting synchronous reluctance motor, comprising a stator assembly and a rotor assembly. The stator assembly includes a stator core and stator windings. The stator core has stator slots, including large stator slots and small stator slots. The outer periphery of the stator core has stator tangents at positions corresponding to the small stator slots, and the total number N of stator tangents is an even number divisible by 3.

[0005] In some embodiments, the stator winding is divided into three phases, which are symmetrically installed in the stator slots at intervals along the circumference of the stator core.

[0006] In some embodiments, the stator winding includes a single-layer stator winding and a double-layer stator winding, wherein the double-layer stator winding is of different phases, the single-layer stator winding is embedded in the stator slot, and the double-layer stator winding is embedded in the stator slot; and / or, the stator slot corresponds to the arc of the outer periphery of the stator.

[0007] In some embodiments, the number of stator slots corresponding to the stator tangent is at least two; and / or, the stator tangent is distributed around the outer periphery of the stator core and is symmetrical about the d-axis and q-axis of the rotor core.

[0008] In some implementations, the flow area formed between the stator tangent and the outer housing should account for more than 40% of the total flow area of ​​the stator and rotor.

[0009] In some implementations, the stator cutting edge includes a short cutting edge and a long cutting edge, and the short cutting edge and the long cutting edge should satisfy 0.7L1≤L2≤L1, where L1 is the length of the long cutting edge and L2 is the length of the short cutting edge.

[0010] In some implementations, the total length of the stator tangent (∑L1+∑L2) and the outer circumference L of the stator core without tangent satisfy 0.4L≤∑L1+∑L2≤0.5L, where L=2πR, and R is the outer radius of the stator core without tangent.

[0011] In some implementations, the minimum distance h1 between the bottom of the stator slot and the stator tangent and the distance h between the bottom of the stator slot and the arc satisfy 0.9h≤h1≤1.1h.

[0012] In some implementations, h ≤ h1 ≤ 1.05h.

[0013] In some implementations, the total area of ​​the stator large slots is 3% to 15% larger than the total area of ​​the stator small slots.

[0014] In some implementations, the total area of ​​the stator large slots is 5% to 8% larger than the total area of ​​the stator small slots.

[0015] In some embodiments, the rotor assembly includes a rotor core with filling slots, slit slots and shaft holes. The filling slots are located on the outer periphery of the rotor core and include a second filling slot and a first filling slot. The second filling slot and the slit slot or the first filling slot form a multilayer magnetic barrier layer of the rotor.

[0016] In some implementations, the magnetic barrier layer under a rotor pole is arranged symmetrically about the q-axis, and more than two layers are arranged radially.

[0017] In some embodiments, in each magnetic barrier layer consisting of a second filling groove and a slit groove, there is a dividing rib between the second filling groove and the slit groove. The width L3 of the dividing rib along the d-axis satisfies L3≥0.5σ, where σ is the width of the air gap between the stator inner diameter and the rotor outer diameter.

[0018] In some implementations, within the first quadrant formed by the d-axis and q-axis, the distance between the center of the dividing rib and the d-axis and the q-axis satisfies kq=-ν*kd+λ, where kq is the distance from the center of the dividing rib to the q-axis, kd is the distance from the center of the dividing rib to the d-axis, and 0.28≤ν≤0.46, 28≤λ≤33.

[0019] In some embodiments, the minimum width d1 of the magnetic channel between two adjacent second filling slots is greater than the minimum width d2 of the magnetic channel formed between the slit slots corresponding to the two second filling slots, where d1 ≥ 1.15d2.

[0020] In some implementations, 1.2d2≤d1≤1.35d2.

[0021] In some embodiments, the minimum distance d3 between two adjacent magnetic barrier layers along the q-axis satisfies d3≥1.5d4, where d4 is the minimum width along the q-axis of the magnetic barrier layer with the smaller width along the q-axis among the two adjacent magnetic barrier layers; and / or, a magnetic channel is formed between two adjacent magnetic barrier layers, and the maximum width of each magnetic channel along the q-axis gradually decreases in the direction away from the d-axis.

[0022] In some embodiments, the width along the d-axis between the ends of the two second filling grooves near the outermost slit groove at both ends of the rotor outer circle is L4; in the inner magnetic barrier layer adjacent to it near the shaft hole, the width along the d-axis between the ends of the two second filling grooves near the slit groove at both ends of the slit groove is L5, 0.2≤L4 / L5≤0.9; and / or, the width along the d-axis between the ends of the two second filling grooves near the slit groove at both ends of the outermost slit groove at both ends of the rotor outer circle is L4; in the innermost magnetic barrier layer near the shaft hole, the width along the d-axis between the ends of the two second filling grooves near the slit groove at both ends of the slit groove is L6, 0.1≤L4 / L6≤0.7.

[0023] In some implementations, 0.45 ≤ L4 / L5 ≤ 0.65; and / or, 0.3 ≤ L4 / L6 ≤ 0.35.

[0024] In some embodiments, in the outermost magnetic barrier layer near the outer circle of the rotor, the distance along the d-axis between the dividing rib between the slit slot and the filling slot and the dividing rib between the adjacent slit slot and the filling slot of the outermost magnetic barrier layer is L7, and the distance along the d-axis between the dividing rib between the slit slot and the filling slot of the outermost magnetic barrier layer and the dividing rib between the slit slot and the filling slot of the innermost magnetic barrier layer near the rotor shaft hole is L8, where 0≤L7 / L8≤0.6.

[0025] In some implementations, 0 ≤ L7 / L8 ≤ 0.4.

[0026] In some implementations, 0 ≤ L7 / L8 ≤ 0.2.

[0027] In some implementations, the ratio of the maximum width of the filling groove along the q-axis to the width of the slit groove along the q-axis in each magnetic barrier layer is τ2, where τ2 > 1.4.

[0028] In some implementations, 1.5 < τ2 < 3.0.

[0029] In some embodiments, the slit groove is composed of arc segments and / or straight segments, and is spaced apart along the q-axis. From the rotor shaft hole side to the rotor outer circle side, the curvature of the arc segment of the slit groove gradually increases, and the curvature of the outer circle of the slit groove in the same layer is greater than that of the inner circle. Alternatively, the two ends of the slit groove generally extend along the d-axis direction, and the width of the slit groove gradually increases from the middle position of the slit groove to both ends.

[0030] In some embodiments, from the rotor shaft hole side to the rotor outer circle side, the curve length between the ends of each layer of slit grooves near the two second filling grooves gradually decreases, and the curve length of adjacent slit grooves decreases by 5% to 20%.

[0031] In some embodiments, the gap d5 between the filling groove and the outer circle of the rotor satisfies d5≥0.5σ, where σ is the width of the air gap between the inner diameter of the stator and the outer diameter of the rotor.

[0032] In some embodiments, the rotor core has at least five different types of filling slots with different filling areas; and / or, the total filling area of ​​the first filling slot and the second filling slot accounts for 30% to 70% of the total area of ​​the first filling slot, the second filling slot and the slit slot.

[0033] In some embodiments, the total filling area of ​​the first filling groove and the second filling groove accounts for 35% to 50% of the total area of ​​the first filling groove, the second filling groove and the slit groove.

[0034] In some implementations, the ratio τ between the maximum and minimum thicknesses of all filled grooves along the q-axis satisfies 1 ≤ τ ≤ 2.

[0035] In some implementations, 1.3 ≤ τ ≤ 1.5.

[0036] In some implementations, the maximum thickness of each second filling groove along the q-axis gradually increases toward the d-axis.

[0037] In some implementations, the maximum width of each second filling groove increases continuously in at least three layers along the q-axis direction, toward the d-axis.

[0038] In some embodiments, the maximum width of each second filling groove decreases continuously along the q-axis direction from the second magnetic barrier layer near the d-axis to the magnetic barrier layer near the outer circle of the rotor, moving away from the d-axis.

[0039] In some embodiments, both the first and second filling slots are filled with conductive but non-magnetic materials, and the filling slots are self-short-circuited by end rings at both ends of the rotor to form a squirrel cage structure.

[0040] In some embodiments, the angle α1 between the two ends of the first filling groove and the rotor center satisfies 20°≤α1≤60°; and / or, the width of the first filling groove along the d-axis is less than the width along the d-axis between the ends of the two second filling grooves in the adjacent magnetic barrier layer that are closer to the slit groove.

[0041] In some implementations, 30°≤α1≤50°.

[0042] In some implementations, 30°≤α1≤35°.

[0043] In some embodiments, the ratio of the distance L9 from the first filling groove to the rotor center in the q-axis direction to the rotor radius Rr satisfies 0.82≤L9 / Rr≤0.96; and / or, the ratio of the distance on the q-axis between the sides of the two innermost magnetic barrier layers near the shaft hole to the width of the shaft on the q-axis is greater than 1.2; and / or, the ratio of the diameter of the arc segment of the side of the innermost magnetic barrier layer near the shaft hole to the width of the shaft on the q-axis is greater than 2.

[0044] In some embodiments, the first filling groove is located on the q-axis direction of the outer periphery of the rotor and extends in a direction parallel to the d-axis.

[0045] In some embodiments, the first filling groove includes a plurality of q-axis filling grooves, and there are ribs between adjacent q-axis filling grooves. The number m of q-axis filling grooves satisfies m≥3, and the ratio of m to rotor radius Rr satisfies m / Rr≥0.07. Meanwhile, the ratio of the sum of the widths of the ribs along the d-axis direction L10 to rotor radius Rr satisfies L10 / Rr≥0.045.

[0046] In some embodiments, the maximum width of the shaft hole in the q-axis direction of the rotor core is not greater than the maximum width of the shaft hole in the d-axis direction; and / or, the shaft hole is composed of arc segments and / or straight segments.

[0047] The present invention also provides a compressor, including the above-described three-phase self-starting synchronous reluctance motor.

[0048] The present invention provides a three-phase self-starting synchronous reluctance motor and compressor. On the one hand, the stator tangent can maximize the flow area of ​​airflow inside the motor, reduce the increase of motor heat, increase cooling capacity, and improve compressor energy efficiency. On the other hand, the stator slots correspond to the stator tangent, which can make the width of the yoke of the stator core more uniform, reduce the saturation of the stator yoke, and make the magnetic lines of force distributed more evenly in the stator core, making full use of the stator and improving motor efficiency. Attached Figure Description

[0049] Figure 1 This is a schematic diagram (axial direction) of the stator and rotor structure of a three-phase self-starting synchronous reluctance motor according to an embodiment of the present invention;

[0050] Figure 2 This is a schematic diagram (axial direction) of the stator and rotor structure of a three-phase self-starting synchronous reluctance motor according to another embodiment of the present invention;

[0051] Figure 3 A comparison diagram of the current waveforms of a motor using the technical solution of the present invention and a motor in the prior art;

[0052] Figure 4 A comparison diagram of harmonic losses between a motor using the technical solution of the present invention and a motor in the prior art;

[0053] Figure 5 This is a comparison chart of the efficiency of the motor using the technical solution of the present invention and the motor in the prior art.

[0054] The reference numerals in the attached figures are as follows:

[0055] 1. Stator core; 2. Stator chamfer; 31. Stator large slot; 32. Stator small slot; 4. Rotor core; 51. Second filling slot; 52. First filling slot; 6. Slit slot; 7. Shaft hole; 8. Dividing rib; 9. Rib. Detailed Implementation

[0056] See also Figures 1 to 5 As shown in the embodiment of the present invention, a three-phase self-starting synchronous reluctance motor for compressors is provided by the present invention, comprising a stator assembly and a rotor assembly. The stator assembly includes a stator core 1 and stator windings, and the rotor assembly includes a rotor core 4, rotor windings, and a shaft. The present invention employs a chamfered edge design on the outer periphery of the stator core 1, which increases the motor's flow area, increases the compressor's cooling capacity, and improves the motor's energy efficiency. Through the combined design of the stator chamfered edge 2, stator large slots 31, stator small slots 32, and single and double-layer windings, the tooth harmonic content of the motor is reduced, motor vibration and noise are lowered, and the stability of motor operation is enhanced; motor harmonic losses are reduced, and motor efficiency is improved. The stator core 1 is formed by stacking stator laminations, and stator slots are constructed on the stator core 1. The rotor core 4 is formed by stacking rotor laminations.

[0057] In this invention, the stator slots include large stator slots 31 and small stator slots 32, with the small stator slots 32 corresponding to the stator tangent edges 2. The large stator slots 31 correspond to the arcs of the outer periphery of the stator. The total number N of the stator tangent edges 2 is an even number, divisible by 3, and the number of a set of small stator slots 32 corresponding to the stator tangent edges 2 is at least two. In this technical solution, on the one hand, the stator tangent 2 can maximize the flow area of ​​airflow inside the motor, reduce the increase of motor heat, increase cooling capacity, and improve compressor energy efficiency; on the other hand, the stator slot 32 corresponds to the stator tangent 2, which can make the width of the yoke of the stator core 1 more uniform, avoid the stator yoke height being too large or too small, affecting the saturation of the stator yoke, and thus make the magnetic lines of force distributed more evenly in the stator core 1, making full use of the stator and improving motor efficiency (understandably, after the magnetic lines of force are saturated in the stator yoke, electrical energy can no longer be converted into more magnetic energy, but can only be converted into heat energy, which will cause the motor to heat up rapidly).

[0058] The total number N of stator tangent edges 2 is an even number and divisible by 3, and the number of stator slots 32 corresponding to each stator tangent edge 2 is at least two. Since the stator tangent edges 2 correspond to the stator slots 32, a single layer of stator winding needs to be embedded in the stator slots 32. This arrangement not only ensures the clamping force between the stator and the motor housing, but also ensures the symmetry of the electromotive force of the three-phase stator windings, which helps to reduce motor vibration and noise and enhance the stability of motor operation. In some embodiments, the outer circumference of the stator is composed of stator tangent edges 2 and arcs. The flow area formed by the stator tangent edges 2 should account for more than 40% of the total flow area of ​​the stator and rotor (including the stator flow area and the total area of ​​the rotor slots 6) to increase the flow area of ​​airflow inside the compressor motor, increase cooling capacity, and improve compressor energy efficiency.

[0059] In some implementations, the stator tangent 2 is distributed around the outer periphery of the stator core 1 and is symmetrical about the d-axis and q-axis to ensure the clamping force between the stator and the motor housing and avoid the impact of stator displacement on motor efficiency.

[0060] In some embodiments, the stator tangent 2 has equal lengths or is divided into a short tangent and a long tangent, and the short tangent and the long tangent should satisfy 0.7L1≤L2≤L1; the total length of the stator tangent 2 (∑L1+∑L2) and the outer circumference of the stator core 1 without tangents should satisfy 0.4L≤∑L1+∑L2≤0.5L, where L=2πR, L is the outer circumference of the stator core 1 without tangents, R is the outer radius of the stator core 1 without tangents, L1 is the length of the long tangent, and L2 is the length of the short tangent. This arrangement aims to maximize the airflow area inside the motor, reducing the increase in motor heat, and to ensure the clamping force between the stator and the motor housing, avoiding the impact of stator displacement on motor efficiency.

[0061] In some embodiments, the minimum distance h1 between the bottom of the stator slot 32 and the stator tangent edge 2 and the distance h between the bottom of the stator slot 31 and the arc of the outer periphery of the stator should satisfy 0.9h ≤ h1 ≤

[0062] 1.1h, or more preferably, h≤h1≤1.05h. This setting ensures that when the stator small slot 32 corresponds to the stator tangent 2 and the stator large slot 31 corresponds to the stator outer peripheral arc, the problem of the stator yoke height being too large or too small is avoided, which would affect the saturation of the stator yoke.

[0063] In some embodiments, the total area of ​​the large stator slots 31 is 3% to 15% larger than the total area of ​​the small stator slots 32, more preferably 5% to 8%. Stator windings are embedded within the stator slots, with a single-layer stator winding embedded in the small stator slots 32 and a double-layer stator winding embedded in the large stator slots 31, and the double-layer windings are of different phases. The stator windings are divided into three phases, which are symmetrically embedded in the stator slots about a circumference to ensure the symmetry of the induced electromotive force of the three-phase windings. This arrangement not only increases the utilization rate of the slot area and reduces the amount of copper used, but also reduces tooth harmonic content through single and double layer windings. Lower tooth harmonics help reduce motor vibration and noise, and enhance the stability of motor operation.

[0064] The rotor core 4 is provided with a filling groove, a slit groove 6 and a shaft hole 7. The filling groove includes a second filling groove 51 and a first filling groove 52. The second filling groove 51 and the slit groove 6 or the first filling groove 52 form a multi-layer magnetic barrier layer of the rotor.

[0065] In some embodiments, the magnetic barrier structure under a rotor pole is symmetrical about the q-axis and arranged in two or more layers radially. Each magnetic barrier layer, consisting of a second filling groove 51 and a slit groove 6, has a dividing rib 8 between the second filling groove 51 and the slit groove 6. The width L3 of the dividing rib 8 along the d-axis satisfies L3≥0.5σ, where σ is the width of the air gap between the stator inner diameter and the rotor outer diameter. The dividing rib 8 can enhance the mechanical strength of the rotor. Limiting the minimum width of the dividing rib 8 can reduce rotor deformation during manufacturing and lower processing difficulty.

[0066] In some implementations, within the first quadrant formed by the d-axis and q-axis, the distance between the center of the dividing rib 8 and the d-axis and the q-axis satisfies kq=-ν*kd+λ, where kq is the distance from the center of the dividing rib 8 to the q-axis, kd is the distance from the center of the dividing rib 8 to the d-axis, the coefficient ν satisfies 0.28≤ν≤0.46 (dimensionless), and the coefficient λ satisfies 28≤λ≤33 (dimensions consistent with kq and kd), thus defining the position and width of the dividing rib 8 to reduce the risk of rotor deformation.

[0067] In some embodiments, the minimum width d1 of the magnetic channel between two adjacent second filling slots 51 is greater than the minimum width d2 of the magnetic channel formed between the slit slots 6 corresponding to the two second filling slots 51. d1 and d2 satisfy d1≥1.15d2, and more preferably, 1.2d2≤d1≤1.35d2. The purpose is to ensure that there is sufficient width between the filling slots to avoid magnetic field saturation and affect the magnetic flux flow of the channels between the magnetic barrier layers.

[0068] In some implementations, the minimum distance d3 between two adjacent magnetic barrier layers along the q-axis should satisfy d3≥1.5d4, where d4 is the minimum width along the q-axis of the magnetic barrier layer with the smaller width among the two adjacent magnetic barrier layers. Limiting the minimum distance between adjacent magnetic barrier layers can reduce the machining difficulty of the rotor and ensure the uniformity and unsaturation of the rotor's magnetic flux density distribution.

[0069] In some implementations, magnetic channels are formed between adjacent magnetic barrier layers, and the maximum width of each magnetic channel in the q-axis direction gradually decreases in the direction away from the d-axis. The magnetic channels closer to the shaft hole 7 have a greater interaction with the stator and a greater impact on motor performance. This design, while making reasonable use of rotor space, ensures the width of the magnetic channels near the shaft hole, which helps to improve motor performance.

[0070] In some embodiments, the width along the d-axis between the ends of the two second filling grooves 51 near the outermost slit groove 6 on the side near the slit groove 6 is L4; in the adjacent inner magnetic barrier layer near the shaft hole, the width along the d-axis between the ends of the two second filling grooves 51 near the slit groove 6 on the side near the slit groove 6 is L5. Therefore, 0.2 ≤ L4 / L5 ≤ 0.9, and more preferably, 0.45 ≤ L4 / L5 ≤ 0.65. Given the limited rotor space, this arrangement can increase the area of ​​the filling grooves and improve the motor's starting capability.

[0071] In some embodiments, the width along the d-axis between the ends of the two second filling grooves 51 near the outermost slit groove 6 on the side near the slit groove 6 is L4; in the innermost magnetic barrier layer near the shaft hole 7, the width along the d-axis between the ends of the two second filling grooves 51 near the slit groove 6 on the side near the slit groove 6 is L6. Therefore, 0.1 ≤ L4 / L6 ≤ 0.7, and more preferably, 0.3 ≤ L4 / L6 ≤ 0.35. Given the limited rotor space, this arrangement can increase the area of ​​the filling grooves and improve the motor's starting capability.

[0072] In some embodiments, in the outermost magnetic barrier layer near the outer circumference of the rotor, the distance along the d-axis between the dividing rib 8 between the slit slot 6 and the filling slot and the dividing rib 8 between the adjacent slit slot 6 and the filling slot in the outermost magnetic barrier layer is L7; the distance along the d-axis between the dividing rib 8 between the slit slot 6 and the filling slot in the outermost magnetic barrier layer and the dividing rib 8 between the slit slot 6 and the filling slot in the innermost magnetic barrier layer near the rotor shaft hole is L8. The ratio of L7 to L8 satisfies 0 ≤ L7 / L8 ≤ 0.6, more preferably, 0 ≤ L7 / L8 ≤ 0.4, and most preferably, 0 ≤ L7 / L8 ≤ 0.2. Limiting the minimum and maximum relative distances of the dividing ribs 8 between each filling slot and the slit slot 6 of the rotor can increase the area of ​​pressure-bearing between the magnetic barrier layers, forming a mutual support effect, thereby reducing rotor deformation during manufacturing and lowering the process difficulty.

[0073] In some embodiments, the ratio of the maximum width of the filling groove along the q-axis to the width of the slit groove 6 along the q-axis in each magnetic barrier layer is τ2, where τ2 > 1.4, preferably 1.5 < τ2 < 3.0. This ensures both the width of the magnetic conductive channel between the inner magnetic barrier layers and a certain proportion of the magnetic barrier layer, thereby improving motor performance.

[0074] In some embodiments, the slit slot 6 is composed of arc segments and / or straight segments, and is spaced apart along the q-axis. From the rotor shaft hole side to the rotor outer circle side, the curvature of the arc segments of the slit slot 6 gradually increases, and the curvature of the outer circle of the slit slot 6 in the same layer is greater than that of the inner circle; or the two ends of the slit slot 6 extend generally along the d-axis direction, and the width of the slit slot 6 gradually increases from the middle position (q-axis) to both ends (d-axis). A shaft hole 7 is opened in the middle of the rotor. This arrangement can increase the utilization rate of rotor space, and the slit slots 6 can be reasonably arranged to increase the rotor salient pole ratio and improve the motor reluctance torque.

[0075] In some embodiments, from the rotor shaft hole side to the rotor outer circle side, the curve length between the ends of each layer of slit slots 6 near the two second filling grooves 51 gradually decreases, and the curve length of adjacent slit slots 6 decreases by 5% to 20%. A shaft hole 7 is provided in the middle of the rotor. The purpose of this arrangement is to ensure a certain proportion of the magnetic barrier layer while making reasonable use of the rotor space, thereby improving motor performance.

[0076] In some implementations, the gap d5 between the filling groove and the outer diameter of the rotor satisfies d5 ≥ 0.5σ, where σ is the width of the air gap between the inner diameter of the stator and the outer diameter of the rotor. This reduces motor leakage flux and improves motor efficiency while ensuring the mechanical strength of the rotor.

[0077] In some embodiments, the rotor structure includes at least five different types of filling slots; the total area of ​​the filling slots (first filling slot 52, second filling slot 51) should account for 30% to 70% of the total area of ​​the rotor slots (first filling slot 52, second filling slot 51, slit slot 6), more preferably, this proportion is 35% to 50%, so as to ensure a certain proportion of filling slot area so that the motor has a certain load-bearing starting capability.

[0078] In some implementations, the ratio τ between the maximum and minimum thicknesses of all filling slots along the q-axis satisfies 1 ≤ τ ≤ 2, and more preferably, this ratio should satisfy 1.3 ≤ τ ≤ 1.5. Limiting this ratio prevents the magnetic channel width from becoming too small due to excessive filling slot thickness along the q-axis, thus affecting efficiency, and also prevents the filling slot area from becoming too small due to excessive filling slot thickness along the q-axis, thus affecting startup.

[0079] In some embodiments, the maximum thickness of each second filling groove 51 along the q-axis gradually increases towards the d-axis; more preferably, the maximum width of each second filling groove 51 along the q-axis increases continuously in at least three layers towards the d-axis; most preferably, the maximum width of each second filling groove 51 along the q-axis continuously decreases towards the direction away from the d-axis, from the second magnetic barrier layer near the d-axis to the magnetic barrier layer near the outer circumference of the rotor. This arrangement ensures an appropriate amount of cast aluminum while making reasonable use of the rotor space, thereby improving the motor's starting capability.

[0080] In some embodiments, both the first filling slot 52 and the second filling slot 51 are filled with a conductive but non-magnetic material, preferably aluminum or an aluminum alloy. The filling slots are self-short-circuited by end rings at both ends of the rotor, forming a squirrel cage structure. The end ring material is the same as the filling material in the filling slots. The self-short-circuited squirrel cage structure provides asynchronous torque during the motor starting phase to achieve self-starting of the motor; the multi-layer magnetic barrier structure provides reluctance torque to the motor to achieve synchronous operation of the motor.

[0081] In some embodiments, the first filling groove 52 is located on the q-axis direction of the outer periphery of the rotor. It can be arranged in blocks or as a whole. The angle α1 between the two ends of the first filling groove 52 and the line connecting it to the rotor center should satisfy 20°≤α1≤60°. More preferably, α1 should satisfy 30°≤α1≤50°. Most preferably, α1 should satisfy 30°≤α1≤35°. With this configuration, the first filling groove 52 forms a magnetic barrier layer and serves as a filling groove. It can act as a magnetic barrier layer to increase the reluctance torque of the motor, and it can also act as a starting squirrel cage to improve the starting performance of the motor.

[0082] In some embodiments, the width of the first filling groove 52 along the d-axis is smaller than the width along the d-axis between the ends of the two second filling grooves 51 in the adjacent magnetic barrier layer near the slit groove 6. Limiting the width of the first filling groove 52 along the d-axis prevents deformation of the rotor towards the shaft hole or outward circle due to excessive width.

[0083] In some embodiments, the ratio of the distance L9 from the first filling groove 52 to the rotor center in the q-axis direction to the rotor radius Rr satisfies 0.82 ≤ L9 / Rr ≤ 0.96. The ratio of the distance on the q-axis between the sides of the two innermost magnetic barrier layers near the shaft hole to the width of the shaft on the q-axis is greater than 1.2. The ratio of the diameter of the arc segment of the side of the innermost magnetic barrier layer near the shaft hole to the width of the shaft on the q-axis is greater than 2. If L9 / Rr is too small, the outermost magnetic channel will be too narrow, increasing motor losses and reducing efficiency; if L9 / Rr is too large, the distance between the first filling groove 52 and the outer circle of the rotor will be too small, increasing the difficulty of processing.

[0084] In some embodiments, the first filling groove 52 is located on the outer periphery of the rotor along the q-axis and extends in a direction parallel to the d-axis. It can be arranged in blocks or as a whole. When arranged in blocks, the first filling groove 52 includes multiple q-axis filling grooves. This arrangement can form a smooth magnetic conductive channel between it and the adjacent magnetic barrier layer.

[0085] In some embodiments, when arranged in blocks, ribs 9 are present between adjacent q-axis filling slots, with the number m satisfying m≥3, and the ratio of m to the rotor radius Rr satisfying m / Rr≥0.07. Simultaneously, the ratio of the sum of the widths L10 of the ribs 9 along the d-axis to the rotor radius Rr satisfies L10 / Rr≥0.045. The outermost magnetic barrier layer, composed of the first filling slots 52, near the outer circumference of the rotor, is the most easily deformed part of the rotor. Dividing the outermost first filling slots 52 into multiple filling slots can reduce rotor deformation at this location. Simultaneously limiting the total width of the ribs 9 between each first filling slot 52 ensures the force-bearing area of ​​the outermost magnetic barrier layer, further enhancing the rotor's mechanical strength, reducing rotor deformation during manufacturing, and lowering the manufacturing difficulty.

[0086] In some embodiments, the maximum width of the shaft hole 7 in the q-axis direction is not greater than the maximum width of the shaft hole 7 in the d-axis direction. A slit slot 6 is provided in the q-axis direction. This arrangement can increase the utilization rate of the rotor space, so as to reasonably arrange the slit slot 6, thereby increasing the rotor salient pole ratio and improving the motor reluctance torque.

[0087] In some embodiments, the shaft hole 7 is composed of arc segments and / or straight segments.

[0088] It is understood that the length, width, thickness, diameter, etc. of the rotor core related structures in this invention can preferably be measured in mm, and other suitable units of measurement can also be selected under reasonable circumstances.

[0089] In some implementations, the three-phase self-starting synchronous reluctance motor, particularly a three-phase self-starting synchronous reluctance two-pole motor, has a load inertia connected to the output end of the motor shaft that is less than 60% of the inertia of the motor's own shaft system.

[0090] Figure 2 As shown, the stator cut edges 2 are of equal length. This arrangement increases the clamping force between the stator core 1 and the motor housing, preventing displacement of the stator core 1 during motor operation. The first filling groove 52 is arranged as a single piece; alternatively, the first filling groove 52 can also be arranged in multiple pieces. The shaft hole 7 is not limited to a circle; it can also be elliptical or a combination of straight lines and arcs. This technical solution achieves the same technical effect as the first embodiment.

[0091] According to an embodiment of the present invention, a compressor is also provided, including the self-starting synchronous reluctance motor described above.

[0092] Figures 3-5The diagram shows a comparison of the current waveform, aluminum loss, and motor efficiency between the present invention and existing technologies. The present invention can reduce the tooth harmonic content of a self-starting synchronous reluctance motor, reduce motor vibration and noise, and enhance the stability of motor operation; it can also reduce motor harmonic losses and improve motor efficiency.

[0093] It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

[0094] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above are merely preferred embodiments of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A three-phase self-starting synchronous reluctance motor, comprising a stator assembly and a rotor assembly, the stator assembly comprising a stator core (1) and stator windings, characterized in that, The stator core (1) is provided with stator slots, which include stator large slots (31) and stator small slots (32). The outer periphery of the stator core (1) has stator tangents (2) at the positions corresponding to the stator small slots (32), and the total number N of stator tangents (2) is an even number that is divisible by 3. The rotor assembly includes a rotor core (4), which is provided with a filling groove, a slit groove (6) and a shaft hole (7). The filling groove is located on the outer periphery of the rotor core (4), and the filling groove includes a second filling groove (51) and a first filling groove (52). The second filling groove (51), the slit groove (6), and the first filling groove (52) form a multi-layer magnetic barrier layer of the rotor; in each magnetic barrier layer composed of the second filling groove (51) and the slit groove (6), there are dividing ribs (8) between the second filling groove (51) and the slit groove (6); in the first quadrant formed by the d-axis and the q-axis, the distance between the center of the dividing rib (8) and the d-axis and the q-axis satisfies kq=-ν*kd+λ, where kq is the distance from the center of the dividing rib (8) to the q-axis, kd is the distance from the center of the dividing rib (8) to the d-axis, and 0.28≤ν≤0.

46. 28≤λ≤33; The first filling groove (52) is located on the q-axis direction of the outer periphery of the rotor and extends in a direction parallel to the d-axis; The first filling groove (52) includes multiple q-axis filling grooves, and there are ribs (9) between adjacent q-axis filling grooves. The number m of q-axis filling grooves satisfies m≥3, and the ratio of m to the rotor radius Rr satisfies m / Rr≥0.

07. At the same time, the ratio of the sum of the widths L10 of the ribs (9) along the d-axis direction to the rotor radius Rr satisfies L10 / Rr≥0.

045.

2. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The stator winding is divided into three phases, and the three-phase windings are symmetrically installed in the stator slots at intervals along the circumference of the stator core (1).

3. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The stator winding includes a single-layer stator winding and a double-layer stator winding. The double-layer stator winding is of different phases. The single-layer stator winding is embedded in the stator small slot (32), and the double-layer stator winding is embedded in the stator large slot (31); and / or, the stator large slot (31) corresponds to the arc of the outer periphery of the stator.

4. The three-phase self-starting synchronous reluctance motor according to any one of claims 1 to 3, characterized in that, The number of stator slots (32) corresponding to each stator tangent (2) is at least 2; the stator tangents (2) are distributed on the outer periphery of the stator core (1) and are symmetrical about the d-axis and q-axis of the rotor core (4).

5. The three-phase self-starting synchronous reluctance motor according to any one of claims 1 to 3, characterized in that, The flow area formed between the stator tangent (2) and the outer casing should account for more than 40% of the total flow area of ​​the stator and rotor.

6. The three-phase self-starting synchronous reluctance motor according to any one of claims 1 to 3, characterized in that, The stator cutting edge (2) includes a short cutting edge and a long cutting edge. The short cutting edge and the long cutting edge should satisfy 0.7L1≤L2≤L1, where L1 is the length of the long cutting edge and L2 is the length of the short cutting edge.

7. The three-phase self-starting synchronous reluctance motor according to claim 6, characterized in that, The total length of the stator tangent (2) ∑L1+∑L2 and the outer circumference L of the stator core (1) when the stator is not tangent satisfy 0.4L≤∑L1+∑L2≤0.5L, where L=2πR, and R is the outer radius of the stator core (1) when the stator is not tangent.

8. The three-phase self-starting synchronous reluctance motor according to claim 3, characterized in that, The minimum distance h1 between the bottom of the stator small slot (32) and the stator tangent (2) and the distance h between the bottom of the stator large slot (31) and the arc satisfy 0.9h≤h1≤1.1h.

9. The three-phase self-starting synchronous reluctance motor according to claim 8, characterized in that, h≤h1≤1.05h.

10. The three-phase self-starting synchronous reluctance motor according to claim 3, characterized in that, The total area of ​​the stator large slot (31) is 3% to 15% larger than the total area of ​​the stator small slot (32).

11. The three-phase self-starting synchronous reluctance motor according to claim 10, characterized in that, The total area of ​​the stator large slot (31) is 5% to 8% larger than the total area of ​​the stator small slot (32).

12. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The magnetic barrier layers under a rotor pole are arranged symmetrically about the q-axis, and the number of layers arranged radially is greater than or equal to 2.

13. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The width L3 of the dividing rib (8) along the d-axis satisfies L3≥0.5σ, where σ is the width of the air gap between the stator inner diameter and the rotor outer diameter.

14. The three-phase self-starting synchronous reluctance motor according to claim 13, characterized in that, The minimum width d1 of the magnetic channel between two adjacent second filling grooves (51) is greater than the minimum width d2 of the magnetic channel formed between the slit grooves (6) corresponding to the two second filling grooves (51), d1≥1.15d2.

15. The three-phase self-starting synchronous reluctance motor according to claim 14, characterized in that, 1.2d2≤d1≤1.35d2.

16. The three-phase self-starting synchronous reluctance motor according to claim 13, characterized in that, The minimum distance d3 between two adjacent magnetic barrier layers along the q-axis satisfies d3≥1.5d4, where d4 is the minimum width along the q-axis of the magnetic barrier layer with the smaller width in the q-axis direction among the two adjacent magnetic barrier layers; and / or, a magnetic channel is formed between two adjacent magnetic barrier layers, and the maximum width of each magnetic channel in the q-axis direction gradually decreases in the direction away from the d-axis.

17. The three-phase self-starting synchronous reluctance motor according to claim 13, characterized in that, The width along the d-axis between the ends of the two second filling grooves (51) near the outermost slit groove (6) of the rotor outer circle is L4. In the inner magnetic barrier layer near the shaft hole, the width along the d-axis between the ends of the two second filling grooves (51) near the slit groove (6) of the rotor outer circle is L5, 0.2≤L4 / L5≤0.9; and / or, the width along the d-axis between the ends of the two second filling grooves (51) near the slit groove (6) of the rotor outer circle is L4. In the innermost magnetic barrier layer near the shaft hole (7), the width along the d-axis between the ends of the two second filling grooves (51) near the slit groove (6) of the rotor outer circle is L6, 0.1≤L4 / L6≤0.

7.

18. The three-phase self-starting synchronous reluctance motor according to claim 17, characterized in that, 0.45≤L4 / L5≤0.65; and / or, 0.3≤L4 / L6≤0.

35.

19. The three-phase self-starting synchronous reluctance motor according to claim 13, characterized in that, In the outermost magnetic barrier layer near the outer circle of the rotor, the distance between the dividing rib (8) between the slit groove (6) and the filling groove and the dividing rib (8) between the adjacent slit groove (6) and the filling groove in the outermost magnetic barrier layer along the d-axis is L7. The distance between the dividing rib (8) between the slit groove (6) and the filling groove in the outermost magnetic barrier layer and the dividing rib (8) between the slit groove (6) and the filling groove in the innermost magnetic barrier layer near the rotor shaft hole along the d-axis is L8. 0≤L7 / L8≤0.

6.

20. The three-phase self-starting synchronous reluctance motor according to claim 19, characterized in that, 0≤L7 / L8≤0.

4.

21. The three-phase self-starting synchronous reluctance motor according to claim 20, characterized in that, 0≤L7 / L8≤0.

2.

22. The three-phase self-starting synchronous reluctance motor according to claim 13, characterized in that, In each magnetic barrier layer, the ratio of the maximum width of the filling groove along the q-axis to the width of the slit groove (6) along the q-axis is τ2, where τ2 > 1.

4.

23. The three-phase self-starting synchronous reluctance motor according to claim 22, characterized in that, 1.5 < τ2 < 3.

0.

24. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The slit groove (6) is composed of arc segments and / or straight segments, and is spaced along the q axis. From the rotor shaft hole side to the rotor outer circle side, the arc of the arc segment of the slit groove (6) gradually increases, and the arc of the outer circle of the slit groove (6) in the same layer is greater than the arc of the inner circle; or, the two ends of the slit groove (6) extend roughly along the d axis direction, and the width of the slit groove (6) gradually increases from the middle position of the slit groove (6) to both ends.

25. The three-phase self-starting synchronous reluctance motor according to claim 24, characterized in that, From the rotor shaft hole side to the rotor outer circle side, the curve length between the ends of each layer of slit groove (6) near the two second filling grooves (51) gradually decreases, and the curve length of adjacent slit grooves (6) decreases by 5% to 20%.

26. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The gap d5 between the filling groove and the outer circle of the rotor satisfies d5≥0.5σ, where σ is the width of the air gap between the inner diameter of the stator and the outer diameter of the rotor.

27. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The rotor core (4) has at least five different filling slots with different filling areas; and / or, the total filling area of ​​the first filling slot (52) and the second filling slot (51) accounts for 30% to 70% of the total area of ​​the first filling slot (52), the second filling slot (51) and the slit slot (6).

28. The three-phase self-starting synchronous reluctance motor according to claim 27, characterized in that, The total filling area of ​​the first filling groove (52) and the second filling groove (51) accounts for 35% to 50% of the total area of ​​the first filling groove (52), the second filling groove (51) and the slit groove (6).

29. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The ratio τ between the maximum and minimum thicknesses of all filling grooves along the q-axis satisfies 1 ≤ τ ≤ 2.

30. The three-phase self-starting synchronous reluctance motor according to claim 29, characterized in that, 1.3≤τ≤1.

5.

31. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The maximum thickness of each second filling groove (51) gradually increases along the q-axis direction towards the d-axis.

32. The three-phase self-starting synchronous reluctance motor according to claim 31, characterized in that, Towards the d-axis, the maximum width of each second filling groove (51) increases continuously in at least three layers along the q-axis direction.

33. The three-phase self-starting synchronous reluctance motor according to claim 32, characterized in that, Moving away from the d-axis, from the second magnetic barrier layer near the d-axis to the magnetic barrier layer near the outer circle of the rotor, the maximum width of each second filling groove (51) decreases continuously along the q-axis direction.

34. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The first filling groove (52) and the second filling groove (51) are both filled with conductive and non-magnetic materials. The filling grooves are self-short-circuited by the end rings at both ends of the rotor to form a squirrel cage structure.

35. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The angle α1 between the two ends of the first filling groove (52) and the center of the rotor satisfies 20°≤α1≤60°; and / or, the width of the first filling groove (52) along the d-axis is less than the width along the d-axis between the ends of the two second filling grooves (51) in the adjacent magnetic barrier layer that are close to the slit groove (6).

36. The three-phase self-starting synchronous reluctance motor according to claim 35, characterized in that, 30°≤α1≤50°。 37. The three-phase self-starting synchronous reluctance motor according to claim 36, characterized in that, 30°≤α1≤35°。 38. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The ratio of the distance L9 from the first filling groove (52) to the rotor center in the q-axis direction to the rotor radius Rr satisfies 0.82≤L9 / Rr≤0.96; and / or, the ratio of the distance on the q-axis between the side of the innermost magnetic barrier layer near the shaft hole and the width of the shaft on the q-axis is greater than 1.2; and / or, the ratio of the diameter of the arc segment of the side of the innermost magnetic barrier layer near the shaft hole and the width of the shaft on the q-axis is greater than 2.

39. The three-phase self-starting synchronous reluctance motor according to claim 1, characterized in that, The maximum width of the shaft hole (7) of the rotor core (4) in the q-axis direction is not greater than the maximum width of the shaft hole (7) in the d-axis direction; and / or, the shaft hole (7) is composed of arc segments and / or straight segments.

40. A compressor, characterized in that, The three-phase self-starting synchronous reluctance motor includes any one of claims 1-39.

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