Self-starting quadrupole synchronous reluctance motor

Abstract

The self-starting quadrupole synchronous reluctance motor comprises a stator and a rotor, a rotor iron core is provided with four magnetic pole sectors, a plurality of magnetic barrier cavities are formed in any magnetic pole sector from the periphery of a shaft hole along the q axis at intervals, and conducting bar grooves are formed in the two ends of each magnetic barrier cavity; an H-shaped integrated filling groove group is arranged between the conducting bar grooves at the two ends of the magnetic barrier cavity, and consists of a plurality of radial grooves and a circumferential groove which penetrates through every two adjacent radial grooves and is arranged between the groove tops and the groove bottoms of the radial grooves, and the groove tops of the radial grooves and the conducting bar grooves are convex arc-shaped; the grooves are spaced in the circumferential direction, and the center lines of the grooves are gathered at the hole center of the shaft hole. According to the self-starting quadrupole synchronous reluctance motor adopting the technical scheme, the excitation current can be effectively reduced, the power factor is increased, and the motor efficiency is improved; the structural strength of the rotor iron core part in the q-axis direction is ensured; and the processing difficulty of the rotor punching sheet and the rotor iron core is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of motors, and in particular to a self-starting four-pole synchronous reluctance motor. Background Art

[0002] Patent document No. ZL201910533865.7 discloses a self-starting synchronous reluctance motor and a compressor having the same, see Figure 1 , 4 As shown, the q-axis filling slot 21 extends along the d-axis and has a certain circumferential length L. Since the q-axis filling slot 21 has already approached the outer peripheral edge limit of the rotor core, not only is the slotting process difficult, which affects the yield rate of the rotor core after slotting, but it will also cause the rotor core to form a mechanical strength weak link at this structure. When aluminum liquid is poured into the slot of the q-axis filling slot 21, it will squeeze the slot wall and cause the rotor core to deform. When the motor is running at high speed, under the action of centrifugal force, the stress borne by the q-axis filling slot 21 close to the outer peripheral side of the rotor core is not conducive to ensuring its yield strength. Once the yield strength is exceeded, the rotor will bulge outward or even be structurally damaged, affecting the normal operation of the motor. Figure 2 , grooves 22 and 23 are arranged adjacent to the two ends of the q-axis filling groove 21, and the two grooves are opened on the outer peripheral side of the rotor core. This unreasonable structure will cause the two end walls of the q-axis filling groove 21 to be hot-extruded during the casting of aluminum liquid, causing the groove to extend and deform, thereby squeezing out the grooves 22 and 23, thereby affecting the normal function of the grooves 22 and 23. Summary of the invention

[0003] The purpose of the present invention is to provide a self-starting four-pole synchronous reluctance motor to solve the problems of low working efficiency of the prior art self-starting synchronous reluctance motor due to excessive excitation current and small power factor, as well as the difficulties in rotor core processing and weak structural strength of the rotor core in the q-axis direction.

[0004] To this end, the present invention provides the following technical solutions:

[0005] A self-starting four-pole synchronous reluctance motor comprises a stator and a rotor, wherein the rotor core has four magnetic pole sectors and in any magnetic pole sector, a plurality of magnetic barrier cavities are provided at intervals along the q axis from the periphery of the shaft hole, and guide bar grooves are provided at both ends of each magnetic barrier cavity in the plurality of magnetic barrier cavities. The improvement is that an H-shaped integrated filling slot group is provided between the guide bar grooves located at both ends of the magnetic barrier cavity, and the H-shaped integrated filling slot group is provided, which consists of a plurality of radial slots and a circumferential slot that passes through two adjacent radial slots and is provided between the slot tops and the slot bottoms of the radial slots, wherein the slot tops of the radial slots and the guide bar grooves are both convex arc-shaped, and the slots are spaced circumferentially and the slot center lines are all converged at the hole center of the shaft hole.

[0006] In the H-shaped integrated filling groove group of the present invention, the radial distance of the radial grooves is not less than 1.1 mm, the radial distance of the circumferential grooves is not less than 0.5 mm, and the distances from the top of the radial groove and the bottom of the radial groove to the circumferential groove are not less than 0.3 mm.

[0007] In order to optimize the structural design of the H-shaped integrated filling slot group of the rotor core of a four-pole synchronous reluctance motor, when the distance between the circumferential slot with a circumferential length and the slot top of the radial slot develops towards <0.3mm, the difficulty of machining the rotor punching and the rotor core continues to increase, and the qualified rate of the outer edge damage of the rotor punching during the machining process is low; when the distance between the circumferential slot and the slot bottom of the radial slot develops towards <0.3mm, the excitation current will increase sharply and be accompanied by a decrease in the power factor, which will eventually lead to a decrease in motor efficiency.

[0008] The present invention also includes a flux blocking slot, which is arranged between the H-shaped integrated filling slot group and the flux barrier cavity and extends along the circumference of the rotor core.

[0009] The rotor core can make the motor present low torque fluctuation performance by optimizing the setting of the flux blocking slots.

[0010] The number of stator slots of the stator and the number of guide bar slots and radial slots of the rotor core are 36, 44, 36, 40 or 36, 28 respectively.

[0011] The number of slots of the above-mentioned stator slots and the number of slots of the guide bar slots and radial slots of the rotor core are 36 and 44 respectively. In any one of the four magnetic pole sectors of the rotor core, there are three magnetic barrier cavities. A pair of two guide bar slots symmetrical about the q axis are adjacently arranged on both end sides of the three magnetic barrier cavities. A group of H-shaped connected filling slot groups is arranged between the guide bar slots on one end side of the three magnetic barrier cavities and the guide bar slots on the other end side of the three magnetic barrier cavities. The group consists of five radial slots and one circumferential slot. The circumferential intervals between the radial slots, between the guide bar slots, and between the radial slots and the guide bar slots are equal.

[0012] The present invention has the following advantages and positive effects:

[0013] After the self-starting four-pole synchronous reluctance motor is applied with the technical solution of the present invention, the exciting current can be effectively reduced, the power factor can be increased and the motor efficiency can be improved; the structural strength of the rotor core in the q-axis direction can be ensured; and the processing difficulty of the rotor punchings and the rotor core can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 1 is a schematic structural diagram of a first embodiment of a self-starting four-pole synchronous reluctance motor according to the present invention;

[0015] Figure 2 is a perspective view of a first embodiment of a rotor of the present invention;

[0016] Figure 3 is a perspective view of a first embodiment of a rotor core of the present invention;

[0017] Figure 4 yes Figure 3 End view of

[0018] Figure 5 Only display Figure 4 A plan view of a magnetic pole sector;

[0019] Figure 6 is an end view of a second embodiment of a rotor core of the present invention;

[0020] Figure 7 Only display Figure 6 A plan view of a magnetic pole sector. DETAILED DESCRIPTION

[0021] See also Figures 1 to 5 As shown, the present invention provides a self-starting four-pole synchronous reluctance motor, including a stator 1 (the winding is conventionally not shown in the figure) and a rotor, the rotor including a rotor core 2 and an end ring 8, the rotor core 2 is centrally symmetrically arranged with four magnetic pole sectors 21 around its axial hole 20 about the intersecting d axis 72, in any magnetic pole sector 21, a plurality of magnetic barrier cavities 3 are spaced apart along the q axis 71 from the periphery of the axial hole 20, and a guide bar groove 4 with a guide bar is respectively arranged at both ends of each magnetic barrier cavity in the plurality of magnetic barrier cavities.

[0022] See also Figure 4 As shown, a filling slot group is provided between the guide slots at both ends of the magnetic barrier cavity. The filling slot group is an H-shaped integrated filling slot group 5. Figure 5 In detail, in the magnetic barrier cavity farthest from the shaft hole among the plurality of magnetic barrier cavities, the H-shaped integrated filling slot group 5 is arranged between the guide slots at both ends of the magnetic barrier cavity ( Figure 4 , 5 The guide bar grooves 4 at both ends of the aforementioned magnetic barrier cavity are marked. The H-shaped integrated filling groove group 5 consists of a plurality of radial grooves 51 and a circumferential groove 52 that passes through any two adjacent radial grooves. The circumferential groove 52 is arranged between the groove tops of the radial grooves 51 and the groove bottoms of the radial grooves 51. The radial grooves 51 and the guide bar grooves 4 are spaced apart in the circumferential direction and their center lines converge at the center of the axial hole 20. The groove tops of the guide bar grooves 4 and the groove tops of the radial grooves 51 are both convex arc-shaped.

[0023] The H-shaped integrated filling slot group 5 axially penetrates the rotor core 2 and is filled with molten aluminum. The circumferential guide bars are formed in the circumferential slots 52 and the axial guide bars are formed in the radial slots 51. The guide bars are all connected to the end ring 8 as a whole.

[0024] The radial slot 51 has a predetermined outer spacing from its convex arc-shaped slot top to the outer peripheral side of the rotor core 2 (specifically depending on the size of the air gap between the stator core and the rotor core, and the predetermined outer spacing in this embodiment is 0.5 mm), and the guide bar slot 4 has a predetermined outer spacing and a predetermined inner spacing from its convex arc-shaped slot top to the outer peripheral side of the rotor core 2 and the guide bar slot 4 has a predetermined outer spacing and a predetermined inner spacing equal to the above-mentioned ones from its slot bottom to the magnetic barrier cavity 3.

[0025] In the H-shaped integrated filling groove group 5, the radial distance of the radial groove 51 is not less than 1.1 mm, the radial distance of the circumferential groove 52 is not less than 0.5 mm, and the distances from the top of the radial groove 51 and the bottom of the radial groove 51 to the circumferential groove 52 are not less than 0.3 mm.

[0026] As another implementation, see Figure 6 , 7 As shown, the present invention further comprises a flux blocking slot 6 which is arranged between the H-shaped integrated filling slot group 5 and the flux barrier cavity 3 and extends along the circumferential direction of the rotor core 2 .

[0027] Since the flux blocking slots are radially away from the outer peripheral side of the rotor core, and the flux blocking slots need to have a certain circumferential extension length according to the process requirements, compared with the prior art in which the flux blocking slots of a predetermined circumferential length are opened on the outer peripheral side of the rotor core, the difficulty of slotting is reduced and the damage of the outer edge of the rotor core can be effectively avoided, thereby correspondingly improving its yield rate and ensuring the safety and reliability of high-speed operation of the motor; if the radial position of the flux blocking slots and the H-shaped integrated filling slot group is swapped, that is, the flux blocking slots are moved outward to the outer peripheral side of the rotor core, not only the slotting difficulty is increased and the yield rate is reduced, but also when aluminum liquid is cast into the slots, it is very likely that the extrusion pressure formed on the slot wall will cause the corresponding parts of the rotor core to produce deformation phenomena of varying degrees, especially when the motor is running at high speed, the stress borne by the flux blocking slots close to the outer peripheral side of the rotor core will inevitably weaken its yield strength due to the influence of centrifugal force. Once the yield strength is exceeded, the rotor core will bulge outward or even be structurally damaged, affecting the normal operation of the motor.

[0028] The number of the stator slots 10 of the stator 1 and the number of the guide bar slots and radial slots of the rotor core 2 can be 36 slots, 44 slots, 36 slots, 40 slots, or 36 slots, 28 slots.

[0029] As an embodiment of the present invention, the number of slots of the stator slot 10, the number of slots of the guide bar slots 4 and the radial slots 51 of the rotor core 2 are 36 slots and 44 slots respectively. In any one of the four magnetic pole sectors of the rotor core 2, there are three magnetic barrier cavities 3. A pair of two guide bar slots symmetrical about the q-axis 71 are adjacently arranged on both end sides of the three magnetic barrier cavities. A group of H-shaped connected filling slot groups 5 are arranged between the guide bar slots on one end side of the three magnetic barrier cavities and the guide bar slots on the other end side of the three magnetic barrier cavities. The group of H-shaped connected filling slot groups 5 consists of five radial slots 51 and one circumferential slot 52. The circumferential spacing between adjacent radial slots 51, between adjacent guide bar slots 4, and between adjacent radial slots 51 and guide bar slots 4 are equal.

[0030] When the number of slots of the stator slot 10 and the number of slots of the guide bar slot and the radial slot of the rotor core 2 are 36 slots and 44 slots respectively, the angle between the center lines of adjacent stator slots 10 and the center of the shaft hole is 10°; the angle between the center lines of adjacent radial slots 51 and the center of the shaft hole 20, the angle between the center lines of adjacent guide bar slots 4 and the center of the shaft hole 20, and the angle between the center lines of adjacent radial slots 51 and the guide bar slots 4 and the center of the shaft hole 20 are all 8.18°.

[0031] The simulation test of the self-starting four-pole synchronous reluctance motor shows that under the same voltage (optimal voltage peak is 300V) and the same load, the current decreases by 5% and the efficiency increases by 1%.

Claims

1. A self-starting four-pole synchronous reluctance motor, comprising a stator and a rotor, wherein the rotor core has four magnetic pole sectors and in any magnetic pole sector, a plurality of magnetic barrier cavities are provided at intervals along the q axis from the periphery of the shaft hole, wherein each of the plurality of magnetic barrier cavities has a guide bar groove at both ends thereof, wherein the motor is characterized in that An H-shaped connected filling slot group is provided between the guide bar slots at both ends of the magnetic barrier cavity, which consists of a plurality of radial slots and a circumferential slot that passes through two adjacent radial slots and is arranged between the slot tops and slot bottoms of the radial slots. The slot tops of the radial slots and the guide bar slots are both convex arc-shaped, and the slots are spaced circumferentially and the slot center lines all converge at the center of the shaft hole.

2. The self-starting four-pole synchronous reluctance motor according to claim 1, characterized in that In the H-shaped connected filling groove group, the radial distance of the radial grooves shall not be less than 1.1 mm, the radial distance of the circumferential grooves shall not be less than 0.5 mm, and the distances from the top of the radial groove and the bottom of the radial groove to the circumferential groove shall not be less than 0.3 mm.

3. The self-starting synchronous reluctance motor according to claim 1 or 2, characterized in that: It also includes a flux blocking empty slot, which is arranged between the H-shaped connected filling slot group and the magnetic barrier air cavity and extends along the circumference of the rotor core.

4. The self-starting four-pole synchronous reluctance motor according to claim 3, characterized in that: The number of stator slots of the stator and the number of guide bar slots and radial slots of the rotor core are 36, 44, 36, 40, or 36, 28 respectively.

5. The self-starting four-pole synchronous reluctance motor according to claim 4, characterized in that: The number of stator slots, the number of guide bar slots and the number of radial slots in the rotor core are 36 and 44 respectively. In any one of the four magnetic pole sectors of the rotor core, there are three magnetic barrier cavities. A pair of two guide bar slots symmetrical about the q axis are adjacently arranged on both ends of the three magnetic barrier cavities. A group of H-shaped connected filling slots is arranged between the guide bar slots on one end side of the three magnetic barrier cavities and the guide bar slots on the other end side of the three magnetic barrier cavities. The group consists of five radial slots and one circumferential slot. The circumferential spacing between the radial slots, between the guide bar slots, and between the radial slots and the guide bar slots is equal.

Images