Self-starting synchronous reluctance motor rotor, rotor assembly, motor, and compressor

Abstract

The application provides a self-starting synchronous reluctance motor rotor, a rotor assembly, a motor and a compressor, the self-starting synchronous reluctance motor rotor comprising a plurality of rotor laminations, the rotor laminations being provided with slit slots, filling slots and shaft holes, wherein the filling slots are arranged in the same layer as the slit slots; the distance d from the slit slot located at the outermost layer of the rotor q-axis to the outer circle of the rotor in the q-axis direction satisfies 0.08<=d / R<=0.16, wherein R is the radius of the rotor; the included angle alpha formed between the outer edge of the filling slot at the two ends of the slit slot located at the outermost layer of the rotor q-axis and the center of the rotor circle satisfies 0.2<=alpha / tau<=0.6, wherein tau is the pole pitch of the motor, that is, tau=180° / p, and p is the pole pair number of the motor. According to the application, the rotor magnetic circuit can be reasonably arranged, the saturation of the motor magnetic circuit is reduced, the influence of the air gap harmonic magnetic field on the squirrel cage is small, the loss of the motor caused by the harmonic magnetic field is reduced, and the efficiency of the motor is improved.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to a self-starting synchronous reluctance motor rotor, rotor assembly, motor, and compressor. Background Technology

[0002] Self-starting synchronous reluctance motors combine the advantages of asynchronous motors with those of synchronous reluctance motors. The asynchronous torque generated by the rotor bars enables the motor to start automatically, and the multi-layered magnetic barrier allows it to operate efficiently at synchronous speed. Compared to asynchronous motors, self-starting synchronous reluctance motors offer constant speed operation and a significant efficiency advantage. Compared to self-starting permanent magnet synchronous motors, self-starting synchronous reluctance motors do not require rare-earth permanent magnets on the rotor, significantly reducing manufacturing costs and eliminating the risk of demagnetization. Compared to ordinary synchronous reluctance motors, self-starting synchronous reluctance motors can achieve self-starting operation without a frequency converter, reducing the overall cost of the motor system and eliminating system losses. However, the rotor of a self-starting synchronous reluctance motor is often designed with a multi-layered magnetic barrier structure, resulting in a complex rotor design and a tendency for magnetic circuit saturation. This leads to increased motor harmonics, and the squirrel cage is significantly affected by harmonic magnetic fields, which is detrimental to improving motor efficiency.

[0003] Because existing self-starting synchronous reluctance motors have technical problems such as complex rotor structure design, easy saturation of magnetic circuit, resulting in increased motor harmonics, and the squirrel cage being greatly affected by harmonic magnetic fields, which is not conducive to improving motor efficiency, this invention studies and designs a self-starting synchronous reluctance motor rotor, rotor assembly, motor and compressor. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the existing self-starting synchronous reluctance motor, which has a complex rotor structure design, is prone to magnetic circuit saturation, resulting in increased motor harmonics, and the squirrel cage is greatly affected by harmonic magnetic fields, which is not conducive to improving the efficiency of the motor. Thus, the present invention provides a self-starting synchronous reluctance motor rotor, rotor assembly, motor and compressor.

[0005] To solve the above problems, the present invention provides a self-starting synchronous reluctance motor rotor, which includes a plurality of rotor laminations. The rotor laminations are provided with slit slots, filling slots and shaft holes, wherein the filling slots and the slit slots are arranged in the same layer, and the filling slots and the slit slots together form a multi-layer magnetic barrier layer structure of the rotor.

[0006] Furthermore, the distance d from the outermost slit slot on the rotor q-axis to the outer circle of the rotor along the q-axis direction satisfies 0.08≤d / R≤0.16, where R is the radius of the rotor; the included angle α formed between the outer edges of the filling grooves at both ends of the outermost slit slot on the rotor q-axis and the center of the rotor satisfies 0.2≤α / τ≤0.6, where τ is the pole pitch of the motor, i.e., τ=180° / p, and p is the number of pole pairs of the motor.

[0007] In some embodiments, the ratio of the length d4 of one of the filling grooves located at both ends of the outermost slit groove along the d-axis to the length d5 ​​of one of the filling grooves at both ends of the adjacent slit groove along the d-axis satisfies 0.2≤d4 / d5≤0.9.

[0008] In some embodiments, the ratio of the length d4 of the filling groove at both ends of the outermost slit groove along the d-axis to the length d6 of the filling groove at both ends of the innermost slit groove along the d-axis satisfies 0.1≤d4 / d6≤0.7.

[0009] In some implementations, a first dividing rib exists between the filling groove in each magnetic barrier layer and the slit grooves arranged in the same layer.

[0010] In some embodiments, the width L of the first dividing rib along the d-axis in the same layer and the width M of the filling groove arranged in the same layer as the first dividing rib near the end of the first dividing rib satisfy 0.2M < L < 0.35M, while the width K of the slit groove arranged in the same layer as the dividing rib near the end of the first dividing rib satisfies K ≤ M.

[0011] In some embodiments, a second dividing rib is provided between the filling groove and the outer circle of the rotor, and the minimum width h1 of all dividing ribs on the rotor lamination satisfies h1≥0.5*σ. All dividing ribs include the first dividing rib and the second dividing rib, where σ is the air gap width between the inner diameter of the motor stator and the outer diameter of the rotor.

[0012] In some embodiments, the width of the first dividing rib of the outermost magnetic barrier layer near the outer circle of the rotor along the d-axis is L1, and the width of the first dividing rib of the innermost magnetic barrier layer near the shaft hole along the d-axis is L2, satisfying L1≥L2.

[0013] In some embodiments, the first dividing rib extends in a direction parallel to or intersecting the q-axis.

[0014] In some implementations, within the first quadrant formed by the d-axis and q-axis, the distance between the center of the first 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 first dividing rib to the q-axis, kd is the distance from the center of the first dividing rib to the d-axis, the coefficient ν satisfies 0.28≤ν≤0.46, and the coefficient λ satisfies 28≤λ≤30.

[0015] In some embodiments, the ratio between the sum of the widths of the slits along the q-axis in all magnetic barrier layers, ∑d1, and the width d2 from the outer circle of the shaft hole to the outer circumference of the rotor is between 0.25 and 0.45, i.e., ∑d1 / d2 = 0.25 to 0.45.

[0016] In some embodiments, the minimum width W of the magnetic channel between two adjacent filling slots satisfies W≥d3, where d3 is the minimum width of the magnetic channel formed between the two slit slots corresponding to the two filling slots.

[0017] In some implementations, the minimum distance h2 of the magnetic channel between two adjacent magnetic barrier layers along the q-axis satisfies h2≥1.5h3, where h3 is the minimum width along the q-axis of the magnetic barrier layer with the smaller width among the two adjacent magnetic barrier layers.

[0018] In some implementations, a magnetic channel is formed between two adjacent magnetic barrier layers, and the width of each magnetic channel gradually decreases in the q-axis direction away from the d-axis.

[0019] In some embodiments, the ratio of the width of the slit groove on the q-axis to the width of the slit groove near the end of the filling groove in each magnetic barrier layer is τ1, and τ1 gradually increases from the innermost magnetic barrier layer to the outermost magnetic barrier layer.

[0020] In some embodiments, the interval between the filling groove of the innermost magnetic barrier layer near the shaft hole and the outer circle of the rotor is h4, and the interval between the outermost magnetic barrier layer near the outer circle of the rotor and the outer circle of the rotor is h5. Then h5≥h4, and 0≤h4≤2.5σ, where σ is the width of the air gap between the inner diameter of the stator and the outer diameter of the rotor.

[0021] In some implementations, the width deviation of the same layer filling groove along the q-axis direction is no greater than 5% along the d-axis direction.

[0022] In some embodiments, in the same layer of filling groove, the width of the end of the filling groove near the outer circle of the rotor along the q-axis is not greater than the width of the end of the filling groove near the shaft hole along the q-axis.

[0023] In some embodiments, the rotor laminations contain at least five different types of filling slots, and the total area of ​​all filling slots on the rotor accounts for 30% to 70% of the total area of ​​all slots on the rotor. The slots include the filling slots and the slit slots.

[0024] In some embodiments, the area of ​​at least three layers of the filling groove gradually decreases from the inside out, and the rate of decrease gradually increases. Here, the rate of decrease is defined as the ratio of the areas of two adjacent layers of the filling groove.

[0025] In some implementations, the ratio τ2 of the maximum and minimum thicknesses of all filling grooves along the q-axis satisfies 1 ≤ τ2 ≤ 2.

[0026] In some embodiments, the width of at least three layers of the filling grooves gradually increases in the direction close to the d-axis.

[0027] In some embodiments, the distance between the midpoint of the filling groove and the midpoint of the adjacent outer filling groove gradually increases from the inside to the outside by at least three layers.

[0028] In some implementations, the ratio of the width of at least three layers of filling grooves along the q-axis from the inside out to the width of the slit groove at the middle position along the q-axis in the same layer is greater than 1.4.

[0029] In some embodiments, the filling grooves are filled with a conductive but non-magnetic material, and the filling grooves are self-short-circuited by end rings at both ends of the rotor to form a squirrel cage structure. The end ring material is the same as the filling material in the filling grooves.

[0030] In some embodiments, the slit groove is composed of arc segments and / or straight segments. From the shaft hole side to the outer circle side of the rotor, 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.

[0031] In some embodiments, the slit groove includes at least one of a straight groove and an arc groove; when a portion of the slit groove is a combination of a straight groove and an arc groove, the slit groove is composed of a straight segment, an arc segment, and a straight segment, with the straight segment parallel to the d-axis and the arc segment protruding in a direction away from the shaft hole; when a portion of the slit groove is an arc groove, the arc segment protrudes in a direction away from the shaft hole; when a portion of the slit groove is a straight groove, the long side of the straight groove is parallel to the d-axis and located at the position closest to the outer circle of the rotor.

[0032] In some embodiments, from the shaft hole side to the outer circle side of the rotor, the curve length between the two ends of each layer of slit grooves that are close to the two filling grooves gradually decreases, and the decrease ratio of the curve length of adjacent slit grooves is 5% to 15%.

[0033] In some implementations, the width of the middle position of at least three slit slots gradually decreases from the inside to the outside along the q-axis.

[0034] In some embodiments, the distance S1 between the arcs of the two innermost slit slots located on both sides of the shaft hole along the q-axis is 1.2-1.3 to the diameter of the rotor shaft hole, and the inner arc diameter of the innermost slit slot is 1.5-3 times the diameter of the rotor shaft hole.

[0035] In some embodiments, the maximum width of the shaft hole in the q-axis direction is not greater than the maximum width of the shaft hole in the d-axis direction.

[0036] In some embodiments, the shaft hole is composed of arc segments and / or straight segments.

[0037] In some implementations, there are magnetic channels between two adjacent magnetic barrier layers, and the width of the ends of all magnetic channels along the d-axis is greater than the width of the center of the magnetic channel, and no filling groove is provided in the middle area of ​​any magnetic channel.

[0038] In some implementations, the width of at least three magnetically conductive channels along the q-axis gradually decreases from the inside to the outside.

[0039] In some implementations, the width of any magnetic channel gradually increases from the middle to both sides along the d-axis direction. Here, the width of the magnetic channel is defined as the shortest distance from any point on one arc to another.

[0040] The present invention also provides a rotor assembly comprising the rotor described in any of the preceding claims, and balancing blocks mounted on end rings at both ends of the rotor, the balancing blocks being disposed on a portion of the end ring with a relatively large radial width between the inner hole and the outer circle of the end ring.

[0041] The present invention also provides an electric motor comprising the aforementioned rotor assembly, wherein the load inertia connected to the output end of the motor shaft is less than 60% of the inertia of the motor shaft system itself.

[0042] The present invention also provides a compressor, including the aforementioned motor.

[0043] The self-starting synchronous reluctance motor rotor, rotor assembly, motor, and compressor provided by this invention have the following beneficial effects:

[0044] 1. This invention achieves this by ensuring that the distance d from the outermost slit slot on the rotor's q-axis to the outer circle of the rotor is 0.08 ≤ d / R ≤ 0.16, and that the angle α between the outer edges of the filling slots at both ends of the outermost slit slot on the rotor's q-axis and the rotor's center is 0.2 ≤ α / τ ≤ 0.6. This eliminates the need for filling slots within a certain range around the rotor, increasing the width of the rat cage from the air gap and reducing the penetration depth of air gap harmonics, thereby reducing rotor aluminum loss. The absence of filling slots in this area also increases the space for the magnetic barrier layer, preventing excessively narrow channels between adjacent magnetic barrier layers that could lead to magnetic circuit saturation. Furthermore, the design of the relative positions and dimensions of the filling slots and slit slots on the rotor allows for a more rational layout of the rotor's magnetic circuit, reducing the likelihood of magnetic circuit saturation and minimizing the impact of air gap harmonic magnetic fields on the rat cage, thus avoiding losses caused by harmonic magnetic fields and ultimately improving motor efficiency.

[0045] 2. This invention also addresses the issue of magnetic circuit saturation by rationally arranging the size and position of the slits or filling slots corresponding to each layer of magnetic barriers in the multi-layer magnetic barrier structure on the first rotor lamination. This reduces motor harmonic content and improves motor operational reliability. The asynchronous torque provided by the rotor bars enables self-starting of the motor, solving the problem of synchronous reluctance motors requiring frequency converter drive, while simultaneously reducing motor losses and improving motor efficiency.

[0046] 3. In each magnetic barrier layer structure, the present invention provides dividing ribs between the filling groove, the slit groove in the same layer, and the outer circle of the rotor. The dividing ribs can enhance the overall structural strength of the rotor on the one hand, and limit magnetic leakage on the other hand, ensuring the salient pole ratio of the motor, thereby ensuring the motor efficiency. Attached Figure Description

[0047] Figure 1 This is a structural diagram of the rotor laminations of the self-starting synchronous reluctance motor rotor according to the first embodiment of the present invention;

[0048] Figure 2 This is a structural diagram of the rotor laminations of the self-starting synchronous reluctance motor rotor according to the second embodiment of the present invention;

[0049] Figure 3 This is a graph comparing the rotor structure of the present invention with the efficiency of existing motors.

[0050] The reference numerals in the attached figures are as follows:

[0051] 1. Rotor lamination; 2. Slit groove; 3. Filler groove; 4. Shaft hole; 5. First dividing rib; 6. Second dividing rib. Detailed Implementation

[0052] like Figure 1-3As shown, the present invention provides a self-starting synchronous reluctance motor rotor, which includes a plurality of rotor laminations 1. The rotor laminations 1 are provided with slit slots 2, filling slots 3 and shaft holes 4. The filling slots 3 are located on the periphery of the rotor and are arranged in the same layer as the slit slots 2. The filling slots 3 and the slit slots 2 together form a multi-layer magnetic barrier layer structure of the rotor.

[0053] Furthermore, the distance d from the outermost slot 2 on the rotor q-axis to the outer circle of the rotor along the q-axis direction satisfies 0.08≤d / R≤0.16 (≤0.16 means there is no second filling slot and the rotor space is reasonably utilized; ≥0.08 is for arranging the magnetic barrier layer, i.e., the slot), where R is the radius of the rotor; the included angle α formed between the outer edge of the filling slot 3 at both ends of the outermost slot 2 on the rotor q-axis and the center of the rotor satisfies 0.2≤α / τ≤0.6 (too large means the space without slots is too large and the space is not reasonably utilized; too small means the slots and cast aluminum slots cannot be reasonably arranged; too small means the distance to the air gap is too close, resulting in larger harmonics), where τ is the pole pitch of the motor, i.e., τ=180° / p, and p is the number of pole pairs of the motor.

[0054] This invention achieves this by ensuring that the distance d from the outermost slit slot along the q-axis to the outer circle of the rotor satisfies 0.08 ≤ d / R ≤ 0.16, and that the angle α formed between the outer edges of the filling grooves at both ends of the outermost slit slot and the rotor center satisfies 0.2 ≤ α / τ ≤ 0.6. This eliminates the need for filling grooves within a certain range around the rotor, thereby increasing the overall width of the rat cage from the air gap (if the outermost slit slot is too close to the shaft hole, it leads to insufficient space utilization, insufficient number of magnetic barrier layers and magnetic channel width, and insufficient magnetic reluctance difference). (The torque capability is relatively weak and cannot guarantee a certain efficiency.) This invention reduces the penetration depth of air gap harmonics, thereby reducing rotor aluminum loss. By not setting a filling slot in this area, the space for setting the magnetic barrier layer can be increased, avoiding magnetic circuit saturation caused by excessively narrow channels between adjacent magnetic barrier layers. Through the design of the relative position and size of the filling slot and slit slot on the rotor, this invention can rationally arrange the rotor magnetic circuit, reducing the occurrence of motor magnetic circuit saturation. At the same time, the air gap harmonic magnetic field has a smaller impact on the squirrel cage, thereby avoiding the loss caused by the harmonic magnetic field to the motor and achieving the goal of improving motor efficiency.

[0055] The specific embodiments of the present invention will now be described with reference to the accompanying drawings. Figure 1The first embodiment of the present invention is shown in the rotor lamination structure diagram. The rotor lamination 1 is provided with a slit groove 2, a filling groove 3, a shaft hole 4, and a dividing rib 5. The filling groove 3 is located on the periphery of the rotor and is arranged in the same layer as the slit groove 2. The filling groove 3 and the slit groove 2 together form a multi-layer magnetic barrier layer structure of the rotor. At the same time, the distance d from the outermost slit groove located on the outer periphery of the rotor q-axis to the outer circle of the rotor along the q-axis direction satisfies 0.08≤d / R≤0.16, where R is the radius of the rotor. The included angle α formed between the outer edges of the filling grooves at both ends of the outermost slit groove located on the outer periphery of the rotor q-axis and the center of the rotor satisfies 0.2≤α / τ≤0.6, where τ is the pole pitch of the motor, i.e., τ=180° / p, and p is the number of pole pairs of the motor. By controlling the distance *d* from the outermost slit slot on the rotor lamination to the outer circle of the rotor, and the angle between the outer edges of the filling grooves at both ends of the outermost slit slot and the rotor center, the area between the outermost magnetic barrier layer and the rotor circumference can be reserved. Ensuring the size of this area increases the distance from the squirrel cage to the air gap magnetic field, reduces the penetration depth of air gap harmonics, thereby reducing rotor aluminum loss and improving motor operating efficiency. (Appendix) Figure 3 A comparison of the motor efficiency of the present invention with that of the prior art reveals that the present invention has a significant advantage in motor efficiency.

[0056] In some embodiments, the ratio of the length d4 of one of the filling slots located at both ends of the outermost slit slot along the d-axis to the length d5 ​​of one of the filling slots located at both ends of the adjacent slit slot along the d-axis satisfies 0.2 ≤ d4 / d5 ≤ 0.9, more preferably 0.45 ≤ d4 / d5 ≤ 0.65. In some embodiments, the ratio of the length d4 of the filling slot at both ends of the outermost slit slot along the d-axis to the length d6 of the filling slot at both ends of the innermost slit slot along the d-axis satisfies 0.1 ≤ d4 / d6 ≤ 0.7, more preferably 0.3 ≤ d4 / d6 ≤ 0.5. Given the limited rotor space, this dimensional arrangement allows for an increase in the area of ​​the filling slots, thereby improving the motor's starting capability.

[0057] In some embodiments, a first dividing rib 5 exists between the filling groove 3 in each magnetic barrier layer and the slit groove 2 arranged in the same layer.

[0058] In some embodiments, the width L of the first dividing rib 5 along the d-axis and the width M of the end of the filling groove 3 arranged in the same layer as the first dividing rib 5 near the first dividing rib 5 satisfy 0.2M < L < 0.35M, while the width K of the end of the slit groove 2 arranged in the same layer as the dividing rib near the first dividing rib 5 satisfies K ≤ M. The presence of the dividing rib can strengthen the mechanical strength of the rotor and enhance the safe and reliable operation of the motor. Limiting the dimensions of the ends of the dividing rib, the filling groove, and the slit groove can increase the area of ​​the magnetic barrier layer that can withstand pressure, thereby reducing the manufacturing difficulty of the rotor.

[0059] In some embodiments, the dividing ribs on the rotor lamination 1 not only exist between the filling groove and the slit groove, but also include a second dividing rib 52 between the filling groove 3 and the outer circle of the rotor. Furthermore, the minimum width h1 of all dividing ribs on the rotor lamination satisfies h1≥0.5*σ. All dividing ribs include the first dividing rib 51 and the second dividing rib 52, where σ is the air gap width between the inner diameter of the motor stator and the outer diameter of the rotor. This arrangement ensures the minimum width of the dividing ribs on the rotor lamination, guaranteeing that each rib has sufficient strength to withstand pressure, thereby reducing the risk of rotor deformation and lowering manufacturing difficulty.

[0060] In some embodiments, the width of the first dividing rib 51 of the outermost magnetic barrier layer near the outer circle of the rotor along the d-axis is L1, and the width of the first dividing rib 51 of the innermost magnetic barrier layer near the shaft hole 4 along the d-axis is L2, satisfying L1≥L2. The dividing rib at the outermost magnetic barrier layer near the outer circle of the rotor bears greater pressure, so the width of the rib needs to be appropriately increased.

[0061] In some embodiments, the first dividing rib 5 extends in a direction parallel to or intersecting the q-axis.

[0062] In some embodiments, within the first quadrant formed by the d-axis and q-axis, the distance from the center of the first dividing rib 5 relative to the d-axis and q-axis satisfies kq = -ν*kd + λ, where kq is the distance from the center of the first dividing rib 5 to the q-axis, kd is the distance from the center of the first dividing rib 5 to the d-axis, the coefficient ν satisfies 0.28 ≤ ν ≤ 0.46, and the coefficient λ satisfies 28 ≤ λ ≤ 30. This is used to limit the position and width of the dividing rib, which contributes to the structural strength of the rotor and reduces the influence of the dividing rib on the rotor's salient pole ratio, thereby minimizing the efficiency reduction caused by the dividing rib.

[0063] In some embodiments, the ratio between the sum of the widths ∑d1 of the slits 2 along the q-axis in all magnetic barrier layers and the width d2 of the distance from the outer circle of the shaft hole 4 to the outer circumference of the rotor is between 0.25 and 0.45, i.e., ∑d1 / d2 = 0.25 to 0.45. More preferably, this ratio is between 0.32 and 0.38. The aim is to select a reasonable magnetic barrier ratio that ensures both sufficient magnetic barrier width and a reasonable magnetic flux path, increasing the motor's saliency ratio while preventing magnetic circuit oversaturation.

[0064] In some embodiments, the minimum width W of the magnetic channel between two adjacent filling slots 3 satisfies W≥d3, where d3 is the minimum width of the magnetic channel formed between the two slit slots 2 corresponding to the two filling slots. This arrangement aims to ensure sufficient width between the filling slots to prevent magnetic field saturation and ensure the smooth flow of magnetic flux between the magnetic barrier layers.

[0065] In some implementations, the minimum distance h2 of the magnetic channel between two adjacent magnetic barrier layers along the q-axis satisfies h2≥1.5h3, where h3 is the minimum width along the q-axis of the smaller magnetic barrier layer among the two adjacent magnetic barrier layers. This setting can reduce the difficulty of rotor manufacturing and ensure the uniformity and unsaturation of the rotor's magnetic flux density distribution.

[0066] In some implementations, magnetic channels are formed between adjacent magnetic barrier layers, and the width of each magnetic channel gradually decreases in the q-axis direction away from the d-axis. The magnetic channels closer to the shaft hole 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 improve motor performance.

[0067] In some embodiments, the ratio of the width of the slit groove 2 on the q-axis to the width of the slit groove near the end of the filling groove in each magnetic barrier layer is τ1, which gradually increases from the innermost magnetic barrier layer to the outermost magnetic barrier layer. This setting ensures both the width of the magnetic conductive channel between the inner magnetic barrier layers and a certain proportion of magnetic barrier layers, thereby improving motor performance.

[0068] In some embodiments, the distance between the innermost magnetic barrier layer filling groove 3 near the shaft hole 4 and the outer circle of the rotor is h4, and the distance between the outermost magnetic barrier layer near the outer circle of the rotor and the outer circle of the rotor is h5. Therefore, h5 ≥ h4, and 0 ≤ h4 ≤ 2.5σ, where σ is the width of the air gap between the stator inner diameter and the rotor outer diameter. This configuration indicates that the filling groove is either an open or closed groove. When the filling groove is a closed groove, limiting its maximum distance from the outer circle of the rotor can reduce magnetic leakage. h4 ≥ h3 can reduce magnetic leakage of the inner magnetic barrier layer while ensuring the mechanical strength at the outer magnetic barrier layer.

[0069] In some implementations, the width deviation of the same-layer filling groove along the q-axis is no greater than 5% along the d-axis direction. The width of the same-layer filling groove is approximately equal from the inside to the outside, with a width deviation of no more than 5%; ensuring the consistency of the width of the same-layer filling groove can guarantee the smoothness of the magnetic conductive channel in this area.

[0070] In some embodiments, in the same layer of filling grooves, the width of the end of the filling groove 3 near the outer circle of the rotor along the q-axis is not greater than the width of the end of the filling groove near the shaft hole 4 along the q-axis. This ensures the width of the magnetic channel near the air gap between the rotor magnetic barrier layers, reducing rotor saturation.

[0071] In some embodiments, the rotor laminations include at least five different types of filling slots, and the total area of ​​all filling slots on the rotor accounts for 30% to 70% of the total area of ​​all slots on the rotor, including the filling slots and the slit slots. More preferably, this proportion is 35% to 50%. This ensures a certain proportion of filling slot area, enabling the motor to have a certain load-bearing starting capability.

[0072] In some embodiments, the area of ​​at least three layers of the filling groove 3 gradually decreases from the inside out, and the rate of decrease gradually increases. Here, the rate of decrease is defined as the ratio of the areas of two adjacent layers of the filling groove 3.

[0073] In some implementations, the ratio τ2 of the maximum and minimum thicknesses of all filling grooves 3 along the q-axis satisfies 1 ≤ τ2 ≤ 2; more preferably 1.4 ≤ τ2 ≤ 1.6. Limiting this ratio prevents the magnetic channel width from becoming too small due to excessive thickness of the filling grooves along the q-axis, thus affecting efficiency, and also prevents the filling groove area from becoming too small due to insufficient thickness of the filling grooves along the q-axis, thus affecting startup.

[0074] In some embodiments, the width of at least three layers of the filling grooves 3 gradually increases in the direction closer to the d-axis. This arrangement ensures an appropriate amount of cast aluminum while making reasonable use of the rotor space, thereby improving the motor's starting capability.

[0075] In some embodiments, the distance between the midpoint of the filling groove 3 and the midpoint of the adjacent outer filling groove 3 gradually increases from the inside to the outside for at least three layers. Simultaneously, the ratio of the width along the q-axis of at least three layers of filling grooves 3 from the inside to the width along the q-axis at the midpoint of the slit groove in the same layer is greater than 1.4, preferably between 1.5 and 3.0. This arrangement conforms to the characteristics of the rotor structure, ensuring sufficient space in the magnetic channel area and preventing magnetic saturation in this region.

[0076] In some embodiments, the filling slots 3 are filled with a conductive but non-magnetic material. The filling slots are self-short-circuited by end rings at both ends of the rotor to form 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.

[0077] In some embodiments, the slit slot 2 is composed of arc segments and / or straight segments. From the side of the shaft hole 4 to the outer circle of the rotor, the curvature of the arc segment of the slit slot gradually increases, and the curvature of the outer circle of the slit slot in the same layer is greater than that of the inner circle. Since there is a shaft hole in the middle of the rotor, this arrangement can increase the utilization rate of the rotor space, and the slit slots can be arranged in a reasonable manner to increase the rotor salient pole ratio and improve the motor reluctance torque.

[0078] In some embodiments, the slit slot 2 includes at least one of a straight slot and an arc-shaped slot; when a portion of the slit slot is a combination of a straight slot and an arc-shaped slot, the slit slot is composed of a straight segment, an arc segment, and a straight segment, with the straight segment parallel to the d-axis and the arc segment protruding away from the shaft hole; when a portion of the slit slot is an arc-shaped slot, the arc segment protrudes away from the shaft hole; when a portion of the slit slot is a straight slot, the long side of the straight slot is parallel to the d-axis and located closest to the outer circle of the rotor. This design allows for full utilization of the inner space of the rotor, maximizing the arrangement of magnetic barrier layers.

[0079] In some embodiments, from the shaft hole 4 side to the outer circle side of the rotor, the curve length between the two ends of each slit groove 2 near the two filling grooves 3 gradually decreases, and the decrease ratio of the curve length of adjacent slit grooves is 5% to 15%. The shaft hole 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 the motor performance.

[0080] In some embodiments, the width of the middle position of at least 3 slit grooves 2 gradually decreases from the inside to the outside along the q-axis.

[0081] In some embodiments, the ratio of the distance S1 between the arcs of the two innermost slit slots 2 located on both sides of the shaft hole 4 along the q-axis to the rotor shaft hole diameter is 1.2-1.3, while the inner arc diameter of the innermost slit slot is 1.5-3 times the rotor shaft hole diameter. This arrangement ensures that there is a sufficient area for the magnetic conductive channel between the innermost slit slot and the shaft hole, thus preventing magnetic saturation in the magnetic conductive channel and ensuring that the rotor structural strength is within a safe range.

[0082] In some embodiments, the maximum width of the shaft hole 4 in the q-axis direction is not greater than the maximum width of the shaft hole 4 in the d-axis direction. This arrangement can increase the utilization rate of rotor space, so as to reasonably arrange the slots, thereby increasing the rotor salient pole ratio and improving the motor reluctance torque.

[0083] In some embodiments, the shaft hole 4 is composed of arc segments and / or straight segments.

[0084] In some embodiments, magnetic channels exist between adjacent magnetic barrier layers. The width at the ends of all magnetic channels along the d-axis is greater than the width at the center of the magnetic channel, and no filling groove is provided in the middle area of ​​any magnetic channel. This ensures the unobstructed flow of the magnetic channels.

[0085] In some implementations, the width of at least three magnetically conductive channels along the q-axis gradually decreases from the inside out. Along the d-axis, the width of any magnetically conductive channel gradually increases from the center outwards; here, the width of the magnetically conductive channel is defined as the shortest distance from any point on one arc to another. This arrangement ensures a balanced ratio between the magnetic barrier layer and the magnetically conductive channels within the limited space of the rotor.

[0086] Figure 2 The figure shows the rotor lamination structure according to the second embodiment of the present invention. As shown, the filling groove and the slit groove are arranged in the same layer, together forming a multi-layer magnetic barrier layer structure of the rotor. In each magnetic barrier layer structure, there are dividing ribs between the filling groove and the slit groove. The dividing ribs extend along the direction of intersection of the q-axis, presenting a parallelogram structure. The rotor shaft hole is a polygonal structure similar to an ellipse composed of multiple straight lines. This embodiment has similar effects to the first embodiment.

[0087] The present invention also provides a rotor assembly comprising the rotor described in any of the preceding claims, and balancing blocks mounted on end rings at both ends of the rotor, the balancing blocks being disposed on a portion of the end ring with a relatively large radial width between the inner hole and the outer circle of the end ring.

[0088] The present invention also provides an electric motor comprising the aforementioned rotor assembly, wherein the load inertia connected to the output end of the motor shaft is less than 60% of the inertia of the motor shaft system itself.

[0089] The present invention also provides a compressor, including the aforementioned motor.

[0090] This invention provides a rotor structure for a self-starting synchronous reluctance motor. The motor achieves self-starting through the asynchronous torque provided by the rotor bars, solving the problem that synchronous reluctance motors require frequency converter drive, while reducing motor system losses and improving the efficiency of motor system operation.

[0091] This invention provides a rotor structure for a self-starting synchronous reluctance motor, which can effectively reduce the losses caused by harmonic magnetic fields during motor operation and improve the overall efficiency of the motor.

[0092] This invention provides a rotor structure for a self-starting synchronous reluctance motor, the main inventive points of which are as follows:

[0093] The laminations corresponding to the rotor structure are provided with filling grooves and slit grooves. The filling grooves are located on the outer periphery of the rotor and are arranged in the same layer as the slit grooves. Together, they constitute the multi-layer magnetic barrier structure of the rotor.

[0094] There is no filling groove in a certain area between the outermost magnetic barrier layer structure and the outer circle of the rotor. At the same time, the distance d from the outermost slit groove on the outer periphery of the rotor along the q-axis to the outer circle of the rotor satisfies 0.08≤d / R≤0.16, where R is the radius of the rotor. The included angle α formed between the outer edge of the filling groove at both ends of the outermost slit groove on the outer periphery of the rotor and the center of the rotor satisfies 0.2≤α / τ≤0.6, where τ is the pole pitch of the motor, i.e., τ=180° / p, and p is the number of pole pairs of the motor.

[0095] By not setting a filling groove in a certain area between the outermost magnetic barrier layer structure and the outer circle of the rotor, the width of the distance between the rat cage and the air gap can be increased, the penetration depth of air gap harmonics can be reduced, and the aluminum consumption of the rotor can be reduced.

[0096] The absence of a filling slot in this area allows for a larger space for the magnetic barrier layer, preventing the magnetic circuit from becoming saturated due to excessively narrow channels between adjacent magnetic barrier layers.

[0097] In each magnetic barrier layer structure, dividing ribs are set between the filling groove, the slit groove in the same layer, and the outer circle of the rotor. The dividing ribs can enhance the overall structural strength of the rotor on the one hand, and limit magnetic leakage on the other hand, ensuring the salient pole ratio of the motor, thereby ensuring the motor efficiency.

[0098] The above description is merely a preferred embodiment of the present invention and is 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 description is only a preferred embodiment 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 self-starting synchronous reluctance motor rotor, characterized in that: It includes multiple rotor laminations (1), and the rotor laminations (1) are provided with slit slots (2), filling slots (3) and shaft holes (4), wherein the filling slots (3) and the slit slots (2) are arranged in the same layer, and the filling slots (3) and the slit slots (2) together form a multi-layer magnetic barrier layer structure of the rotor; Furthermore, the distance d from the outermost slit groove (2) located on the q-axis of the rotor to the outer circle of the rotor along the q-axis direction satisfies 0.08≤d / R≤0.16, where R is the radius of the rotor; the angle α formed between the outer edge of the filling groove (3) at both ends of the outermost slit groove (2) located on the q-axis of the rotor and the center of the rotor satisfies 0.2≤α / τ≤0.6, where τ is the pole pitch of the motor, i.e. τ=180° / p, and p is the number of pole pairs of the motor.

2. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The ratio of the length d4 of one of the filling grooves located at both ends of the outermost slit groove along the d-axis to the length d5 ​​of one of the filling grooves at both ends of the adjacent slit groove along the d-axis satisfies 0.2≤d4 / d5≤0.

9.

3. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The ratio of the length d4 of the filling groove at both ends of the outermost slit groove along the d-axis to the length d6 of the filling groove at both ends of the innermost slit groove along the d-axis satisfies 0.1≤d4 / d6≤0.

7.

4. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: There is a first dividing rib (5) between the filling groove (3) in each magnetic barrier layer and the slit groove (2) arranged in the same layer.

5. The self-starting synchronous reluctance motor rotor according to claim 4, characterized in that: The width L of the first dividing rib (5) along the d-axis and the width M of the end of the filling groove (3) arranged in the same layer as the first dividing rib (5) near the first dividing rib (5) satisfy 0.2M < L < 0.35M. At the same time, the width K of the end of the slit groove (2) arranged in the same layer as the dividing rib near the first dividing rib (5) satisfies K ≤ M.

6. The self-starting synchronous reluctance motor rotor according to claim 4, characterized in that: A second dividing rib (52) is also provided between the filling groove (3) and the outer circle of the rotor, and the minimum width h1 of all the dividing ribs on the rotor laminations satisfies h1≥0.5*σ. All the dividing ribs include the first dividing rib (51) and the second dividing rib (52), where σ is the air gap width between the inner diameter of the motor stator and the outer diameter of the rotor.

7. The self-starting synchronous reluctance motor rotor according to claim 4, characterized in that: The width of the first dividing rib (51) of the outermost magnetic barrier layer near the outer circle of the rotor along the d-axis is L1, and the width of the first dividing rib (51) of the innermost magnetic barrier layer near the shaft hole (4) along the d-axis is L2, satisfying L1≥L2.

8. The self-starting synchronous reluctance motor rotor according to claim 4, characterized in that: The first dividing rib (5) extends in a direction parallel to or intersecting the q-axis.

9. The self-starting synchronous reluctance motor rotor according to claim 4, characterized in that: Within the first quadrant formed by the d-axis and q-axis, the distance between the center of the first dividing rib (5) and the d-axis and q-axis satisfies kq=-ν*kd+λ, where kq is the distance from the center of the first dividing rib (5) to the q-axis, kd is the distance from the center of the first dividing rib (5) to the d-axis, the coefficient ν satisfies 0.28≤ν≤0.46, and the coefficient λ satisfies 28≤λ≤30.

10. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The ratio between the sum of the widths of the slits (2) in all magnetic barrier layers along the q-axis direction, ∑d1, and the width d2 of the outer circle of the shaft hole (4) to the outer circumference of the rotor is between 0.25 and 0.45, i.e., ∑d1 / d2 = 0.25 to 0.

45.

11. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The minimum width W of the magnetic channel between two adjacent filling grooves (3) satisfies W≥d3, where d3 is the minimum width of the magnetic channel formed between the two slit grooves (2) corresponding to the two filling grooves.

12. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The minimum distance h2 of the magnetic channel between two adjacent magnetic barrier layers along the q-axis satisfies h2≥1.5h3, where h3 is the minimum width along the q-axis of the magnetic barrier layer with the smaller width among the two adjacent magnetic barrier layers.

13. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: A magnetic channel is formed between two adjacent magnetic barrier layers. The width of each magnetic channel gradually decreases in the q-axis direction away from the d-axis.

14. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: In each magnetic barrier layer, the ratio of the width of the slit groove (2) on the q axis to the width of the slit groove near the end of the filling groove is τ1, and τ1 gradually increases from the innermost magnetic barrier layer to the outermost magnetic barrier layer.

15. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The interval between the innermost magnetic barrier layer filling groove (3) near the shaft hole (4) and the outer circle of the rotor is h4, and the interval between the outermost magnetic barrier layer near the outer circle of the rotor and the outer circle of the rotor is h5. Then h5≥h4, and 0≤h4≤2.5σ, where σ is the width of the air gap between the inner diameter of the stator and the outer diameter of the rotor.

16. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: Along the d-axis, the width deviation of the same layer of filling grooves along the q-axis is no greater than 5%.

17. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: In the same layer of filling groove, the width of the end of the filling groove (3) near the outer circle of the rotor along the q axis is not greater than the width of the end of the filling groove near the shaft hole (4) along the q axis.

18. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The rotor lamination contains at least five different types of filling grooves, and the total area of ​​all filling grooves on the rotor accounts for 30% to 70% of the total area of ​​all grooves on the rotor. All grooves include the filling grooves and the slit grooves.

19. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The area of ​​at least three layers of filling grooves (3) gradually decreases from the inside out, and the rate of decrease gradually increases. Here, the rate of decrease is defined as the ratio of the areas of two adjacent layers of filling grooves (3).

20. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The ratio τ2 of the maximum and minimum thicknesses of all filling grooves (3) along the q-axis satisfies 1≤τ2≤2.

21. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The width of at least three layers of the filling groove (3) gradually increases in the direction of approaching the d-axis.

22. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The distance between the midpoint of the filling groove (3) and the midpoint of the adjacent outer filling groove (3) gradually increases from the inside to the outside by at least 3 layers.

23. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: Along the q-axis, there are at least 3 layers of filling grooves (3) from the inside to the outside. The ratio of the width along the q-axis of the grooves (3) to the width along the q-axis of the middle position of the slit grooves in the same layer is greater than 1.

4.

24. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The filling groove (3) is filled with a conductive but non-magnetic material. The filling groove is self-short-circuited by the end rings at both ends of the rotor to form a squirrel cage structure. The end ring material is the same as the filling material in the filling groove.

25. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The slit groove (2) is composed of arc segments and / or straight segments. From the side of the shaft hole (4) to the outer circle side of the rotor, the arc of the arc segment of the slit groove gradually increases, and the arc of the outer circle of the slit groove in the same layer is greater than the arc of the inner circle.

26. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The slit groove (2) includes at least one of a straight groove and an arc groove; when a portion of the slit groove is a combination of a straight groove and an arc groove, the slit groove is composed of a straight segment, an arc segment and a straight segment, and the straight segment is parallel to the d-axis, and the arc segment protrudes in a direction away from the shaft hole; when a portion of the slit groove is an arc groove, the arc segment protrudes in a direction away from the shaft hole; when a portion of the slit groove is a straight groove, the long side of the straight groove is set parallel to the d-axis and is located at the position closest to the outer circle of the rotor.

27. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: From the shaft hole (4) side to the outer circle side of the rotor, the curve length between the two ends of each layer of slit groove (2) that are close to the two filling grooves (3) gradually decreases, and the curve length of adjacent slit grooves decreases by 5% to 15%.

28. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The width of the middle position of at least 3 slit grooves (2) along the q-axis gradually decreases from the inside to the outside.

29. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The two innermost slit grooves (2) located on both sides of the shaft hole (4) have a distance S1 between their arcs near the shaft hole along the q axis and a rotor shaft hole diameter of 1.2-1.

3. Meanwhile, the inner arc diameter of the innermost slit groove is 1.5-3 times the rotor shaft hole diameter.

30. The self-starting synchronous reluctance motor rotor according to claim 1, characterized in that: The maximum width of the shaft hole (4) in the q-axis direction is not greater than the maximum width of the shaft hole (4) in the d-axis direction.

31. The rotor of the self-starting synchronous reluctance motor according to any one of claims 1-30, characterized in that: The shaft hole (4) is composed of arc segments and / or straight segments.

32. The rotor of the self-starting synchronous reluctance motor according to any one of claims 1-31, characterized in that: There are magnetic channels between two adjacent magnetic barrier layers. The width of the end of all magnetic channels along the d-axis is greater than the width of the center of the magnetic channel, and there is no filling groove in the middle area of ​​any magnetic channel.

33. The self-starting synchronous reluctance motor rotor according to claim 32, characterized in that: The width of at least three magnetically conductive channels along the q-axis gradually decreases from the inside to the outside.

34. The self-starting synchronous reluctance motor rotor according to claim 32, characterized in that: Along the d-axis, from the middle to both sides, the width of any magnetic channel gradually increases. Here, the width of the magnetic channel is defined as the shortest distance from any point on one arc to another.

35. A rotor assembly, characterized in that: The rotor includes any one of claims 1-34, and a balance block is installed on the end rings at both ends of the rotor, the balance block being disposed on a portion of the end ring with a relatively large radial width between the inner hole and the outer circle of the end ring.

36. An electric motor, characterized in that: Including the rotor assembly of claim 35, the load inertia connected to the shaft output end of the motor is less than 60% of the inertia of the motor's own shaft system.

37. A compressor comprising the motor of claim 36.

Images