Double-permanent-magnet rotor speed-adjusting motor with multi-wind-path heat dissipation structure

Abstract

The application relates to the technical field of permanent magnet motors, in particular to a double-permanent-magnet-rotor speed regulating motor with a multi-air-path heat dissipation structure, which comprises a machine base, an air cooler mounted on the top of the machine base, a motor winding stator arranged in the machine base, an intermediate permanent magnet rotor arranged in the inner cavity of the motor winding stator, a speed regulating winding rotor arranged in the inner cavity of the intermediate permanent magnet rotor, and an external fan rotating synchronously with the output shaft of the speed regulating winding rotor. The internal and external fan form an internal-external cooperative circulation heat dissipation structure, effectively solve the problems of high-temperature demagnetization of permanent magnets and high temperature of bearings caused by heat accumulation of the integrated winding and rotor loss heating, and the whole machine has high integration, uniform heat dissipation and low cooling energy consumption.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet motor technology, and in particular to a dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure. Background Technology

[0002] The dual permanent magnet rotor speed-regulating motor integrates a permanent magnet motor and a permanent magnet coupled speed-regulating rotor, eliminating the need for couplings and achieving a unified coaxial arrangement. Several core heat sources exist during equipment operation: heat generation from the motor stator windings and speed-regulating rotor windings, heat generation from rotor core losses, and heat generation from eddy current losses due to slip. Under high-power conditions, temperature rise can easily exceed limits.

[0003] Existing similar heat dissipation structures have the following drawbacks: First, separate independent heat dissipation: the motor side and the permanent magnet speed-regulating coupling side are respectively equipped with air cooling or water cooling, and the two sets of cooling pipes and fans are arranged independently. The whole machine is large in size, the piping is complex, the heat exchange heat cannot be shared and utilized, and the cooling energy consumption is high. Second, heat dissipation blind zone of dual permanent magnet coupling cavity: the two-stage permanent magnet rotors are coaxially nested, and the middle sandwich is closed without air guiding channels. Various copper loss and iron loss heat are trapped inside the coupling cavity, and the heat cannot be quickly transferred to the outer shell cooling medium.

[0004] Therefore, how to achieve efficient and coordinated heat dissipation of dual permanent magnet rotor speed-regulating motors and eliminate the heat dissipation blind zone of the coupling cavity is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing dual permanent magnet rotor speed regulating motor adopts a separate independent air path heat dissipation method, which has high cooling energy consumption, and the dual permanent magnet coupling cavity has a heat dissipation blind zone, and the heat loss is retained and cannot be quickly discharged, which affects the performance of permanent magnets and bearing life.

[0006] The technical solution adopted by this invention to solve its technical problem is: a dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure, including a frame, a left end cover, a housing, and a right end cover; an air cooler is installed on the top of the frame; a motor winding stator is provided inside the frame, the motor winding stator including a working winding and a stator core, the working winding being connected to the power grid through a phase detection module; a middle permanent magnet rotor is provided inside the motor winding stator cavity, the middle permanent magnet rotor including a rotor left end cover, a middle housing, an outer permanent magnet group, an inner permanent magnet group, a rotor right end cover, and a built-in fan, the built-in fan being installed on the rotor right end cover, the outer permanent magnet group and the motor winding stator forming an outer permanent magnet motor. The generator set consists of an internal permanent magnet generator set; a speed-regulating winding rotor is located inside the middle permanent magnet rotor cavity, which includes an internal winding and an output shaft. The internal winding and the internal permanent magnet assembly form an internal permanent magnet generator set; a connecting flange is fixedly connected to the right end cover of the base; an external guide fan is fixedly connected to the connecting flange; an external fan that rotates synchronously with the output shaft is fitted on the output shaft, and the radial centrifugal air of the external fan is converted into axial air and blown towards the heat dissipation surface of the bearing through the external guide fan; a slip ring cover is also fixedly connected to the connecting flange; a slip ring is fitted on the output shaft, and the internal winding is connected to the slip ring through a line passing through the output shaft; a brush holder is fixedly connected to the slip ring cover, and the brush holder is located on the outer circumference of the slip ring.

[0007] Furthermore, the air cooler includes a centrifugal fan and an axial fan, with the cooler's cold air outlet on the left and the regenerated air outlet on the right.

[0008] Furthermore, a cooling airflow path is formed between the stiffeners of the frame and the stator core, flowing from the left side to the right side of the ventilation channel in the middle of the stiffener, carrying away the heat generated by the motor winding stator.

[0009] Furthermore, ventilation holes are provided on the left and right end covers of the rotor. The built-in fan rotates synchronously with the intermediate permanent magnet rotor, drawing the cold air output from the air cooler into the cavity of the intermediate permanent magnet rotor. The air is then discharged through the shaft rib sleeve of the output shaft from the ventilation hole on the right end cover of the rotor, carrying away the heat generated by the speed regulating winding rotor.

[0010] Furthermore, the external fan rotates synchronously with the output shaft. The air inlet of the external fan is the central through hole and the bottom air inlet of the slip ring cover. The centrifugal air carries away the heat and accumulated carbon powder inside the slip ring cover and blows it towards the bearing heat dissipation surface to reduce the bearing temperature.

[0011] Furthermore, the output shaft of the speed regulating winding rotor is rotatably supported on the machine base via bearings.

[0012] Furthermore, the left and right end covers of the intermediate permanent magnet rotor are rotatably supported on the base by bearings.

[0013] Furthermore, energizing the working winding generates a rotating electromagnetic field, which couples with the permanent magnetic field of the outer permanent magnet group of the intermediate permanent magnet rotor, driving the intermediate permanent magnet rotor to achieve synchronous speed. The internal winding cuts the magnetic lines of force of the rotating inner permanent magnet group to generate induced electromotive force and induced current. By controlling the magnitude of the induced current, the output speed of the speed regulating winding rotor can be controlled. During speed regulation operation, the current of the internal winding is connected to the control system through the slip ring for speed regulation control and slip power feedback.

[0014] Furthermore, a stator core ventilation channel is provided on the stator core, and a shaft rib sleeve ventilation channel is provided on the output shaft.

[0015] The beneficial effects of this invention are as follows: The built-in fan rotates synchronously with the intermediate permanent magnet rotor, drawing cool air from the air cooler into the intermediate permanent magnet rotor cavity to form an internal airflow circulation. This, combined with the external fan rotating synchronously with the output shaft to deliver air into the external guide shroud, forms an external airflow path. This achieves coordinated internal and external airflow cooling, solving the problems of blind spots in the coupling cavity's heat dissipation and heat accumulation in the windings. The heat dissipation is uniform, and the cooling energy consumption is low. The slip energy of the internal permanent magnet generator set is connected to the control cabinet via the collector ring carbon brush. The control cabinet controls the speed regulation and feeds the slip power back to the power grid, achieving energy-saving speed regulation control. The overall structure achieves a coaxial integrated arrangement of the driving permanent magnet motor and the permanent magnet coupled speed-regulating rotor, eliminating the coupling. This results in high integration of the entire machine, enabling long-term stable operation in high-power fan and pump speed regulation scenarios in mines and power plants, significantly improving continuous working reliability. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is a schematic diagram of the structure of the present invention.

[0018] Figure 2 This is a schematic diagram of the machine base.

[0019] Figure 3 This is a schematic diagram of the motor winding stator.

[0020] Figure 4 This is a schematic diagram of the stator core ventilation duct.

[0021] Figure 5 This is a schematic diagram of the structure of the intermediate permanent magnet rotor.

[0022] Figure 6 This is a schematic diagram of the ventilation holes on the left and right end caps of the central permanent magnet rotor.

[0023] Figure 7 This is a schematic diagram of the rotor structure of the speed regulating winding.

[0024] Figure 8This is a schematic diagram of the ventilation duct of the rotor shaft reinforcement sleeve of the speed regulating winding.

[0025] Figure 9 This is a structural diagram of the built-in fan.

[0026] Figure 10 This is a schematic diagram of an external fan.

[0027] Explanation of reference numerals in the attached drawings: 1. Frame; 101. Left end cover; 102. Housing; 103. Right end cover; 2. Air cooler; 3. Motor winding stator; 301. Working winding; 302. Stator core; 3021. Stator core ventilation duct; 4. Intermediate permanent magnet rotor; 401. Rotor left end cover; 402. Intermediate housing; 403. Outer permanent magnet assembly; 404. Inner permanent magnet assembly; 405. Rotor right end cover; 406. Built-in fan; 5. Speed ​​regulating winding rotor; 501 502. Internal winding; 5021. Output shaft; 5022. Shaft rib sleeve ventilation duct; 6. Connecting flange; 7. External guide fan cover; 8. External fan; 10. Slip ring cover; 11. Slip ring; 12. Brush holder; 13. First support bearing of output shaft; 14. Second support bearing of output shaft; 18. Third support bearing of output shaft; 15. First support bearing of intermediate rotor; 16. Second support bearing of intermediate rotor; 17. Third support bearing of intermediate rotor; 19. Motor junction box. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0029] like Figures 1 to 10 The illustrated dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure includes a base 1, which comprises a left end cover 101, a housing 102, and a right end cover 103. An air cooler 2 is mounted on the top of the base 1. The air cooler 2 includes a centrifugal fan and an axial fan. The centrifugal fan has an airflow rate of 1.5 cubic meters per second, and the axial fan has an airflow rate of 2.5 cubic meters per second. The left side of the cooler has a cold air outlet, and the right side has a hot air outlet. A motor junction box 19 is mounted on the front of the housing 102, and the motor junction box 19 is connected to the working winding 301 via wiring.

[0030] The frame 1 houses a motor winding stator 3, which includes a working winding 301 and a stator core 302. The working winding 301 is connected to the power grid via a phase detection module. A cooling airflow path is formed between the stiffeners of the frame 1 and the stator core 302, flowing from the left to the right of the ventilation channel in the middle of the stiffeners. This airflow path carries away the heat generated by the motor winding stator 3, achieving the first level of stator heat dissipation. A stator core ventilation channel 3021 is provided on the stator core 302 to further improve ventilation and heat dissipation efficiency.

[0031] The stator 3 of the motor winding has an internal cavity housing a central permanent magnet rotor 4. The central permanent magnet rotor 4 is a rotating component and includes a left end cover 401, a central housing 402, an outer permanent magnet assembly 403, an inner permanent magnet assembly 404, a right end cover 405, and a built-in fan 406. The built-in fan 406 is mounted on the right end cover 405 and rotates synchronously with the central permanent magnet rotor 4. The outer permanent magnet assembly 403 and the stator 3 of the motor winding form an outer permanent magnet motor assembly, serving as the driving power source. The left end cover 401 and the right end cover 405 of the central permanent magnet rotor 4 are rotatably supported on the base 1 by bearings 15, 16, and 17. Ventilation holes are provided on both the left end cover 401 and the right end cover 405; the ventilation hole on the left end cover 401 serves as a cold air inlet, and the ventilation hole on the right end cover 405 serves as a hot air outlet.

[0032] The intermediate permanent magnet rotor 4 has a speed-regulating winding rotor 5 inside its cavity. The speed-regulating winding rotor 5 includes an internal winding 501 and an output shaft 502. The internal winding 501 and the internal permanent magnet assembly 404 form an internal permanent magnet generator set. A shaft rib ventilation channel 5021 is provided on the output shaft 502 as an exhaust channel for the internal cooling air. The output shaft 502 of the speed-regulating winding rotor 5 is rotatably supported on the base 1 by bearings 13, 14 and 18.

[0033] Regarding the heat dissipation airflow, this invention forms a dual-circulation heat dissipation structure with internal and external coordination. Internal airflow circulation: The built-in fan 406 rotates synchronously with the intermediate permanent magnet rotor 4, drawing the cool air output from the air cooler 2 into the cavity of the intermediate permanent magnet rotor 4 through the ventilation holes of the left end cover 401 of the rotor. The cool air flows through the internal winding 501 and the surface of the output shaft 502 of the speed-regulating winding rotor 5, carrying away the heat generated by the speed-regulating winding rotor 5. Then, it is discharged from the ventilation holes of the right end cover 405 of the rotor through the shaft rib sleeve ventilation channel 5021 of the output shaft 502, completing the internal circulation. External airflow circulation: The external fan 8 rotates synchronously with the output shaft 502. The air inlet of the external fan 8 is the central through-hole and the bottom air inlet of the slip ring cover 10. Centrifugal air carries away the heat and accumulated carbon powder inside the slip ring cover 10 and simultaneously blows it onto the bearing heat dissipation surface, reducing the temperature of bearings 13 and 14. The two circulating air paths work together to solve the problem of heat dissipation blind spots inside the dual permanent magnet coupling cavity, and the external fan ensures heat dissipation for the brush and slip ring parts.

[0034] In terms of electrical control, a connecting flange 6 is fixedly connected to the right end cover 103 of the base 1. An external guide shroud 7 and a slip ring guard 10 are fixedly fixed to the connecting flange 6. A slip ring 11 is fitted onto the output shaft 502, and the internal winding 501 is connected to the slip ring 11 via a wire passing through the output shaft 502. A brush holder 12 is fixedly connected to the slip ring guard 10. The brush holder 12 is located on the outer periphery of the slip ring 11, and electrical connection is achieved through the sliding contact between the brush and the slip ring 11. The connecting flange 6 also serves to support the external guide shroud 7 and the slip ring guard 10.

[0035] The working process of this invention is as follows: Energizing the working winding 301 generates a rotating electromagnetic field; this rotating electromagnetic field couples with the permanent magnetic field of the outer permanent magnet group 403 of the intermediate permanent magnet rotor 4, driving the intermediate permanent magnet rotor 4 to achieve synchronous speed; when the intermediate permanent magnet rotor 4 rotates, the internal winding 501 of the speed-regulating winding rotor 5 cuts the magnetic lines of force of the inner permanent magnet group 404, generating induced electromotive force and induced current. By controlling the magnitude of the induced current, the output speed of the speed-regulating winding rotor 5 can be controlled. During speed regulation, the slip energy of the internal permanent magnet generator set is electrically connected to the control cabinet through the slip ring 11 and carbon brush 12. The control cabinet controls the speed regulation and feeds the slip power back to the power grid, achieving energy-saving speed regulation control. Simultaneously, the built-in fan 406 and the external fan 8 rotate synchronously with the corresponding rotor, achieving self-driven cooling without the need for additional cooling fan drive power supply.

[0036] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure, comprising a frame (1), characterized in that: The base (1) includes a left end cover (101), a housing (102), and a right end cover (103); an air cooler (2) is installed on the top of the base (1); a motor winding stator (3) is provided inside the base (1), the motor winding stator (3) includes a working winding (301) and a stator core (302), the working winding (301) is connected to the power grid through a phase detection module; the inner cavity of the motor winding stator (3) is provided with an intermediate permanent magnet rotor ( 4) The intermediate permanent magnet rotor (4) includes a rotor left end cover (401), an intermediate shell (402), an outer permanent magnet group (403), an inner permanent magnet group (404), a rotor right end cover (405), and a built-in fan (406). The built-in fan (406) is installed on the rotor right end cover (405). The outer permanent magnet group (403) and the motor winding stator (3) form an outer permanent magnet motor group. The intermediate permanent magnet rotor (4) has a speed-regulating winding rotor (5) in its inner cavity. The speed-regulating winding rotor (5) includes an internal winding (501) and an output shaft (502). The internal winding (501) and the internal permanent magnet assembly (404) form an internal permanent magnet generator set. A connecting flange (6) is fixedly connected to the right end cover (103) of the base (1). An external guide fan shroud (7) is fixedly connected to the connecting flange (6). An external fan (8) that rotates synchronously with the output shaft (502) is fitted on the output shaft (502). The external guide fan... Inside the cover (7), the radial centrifugal air of the external fan (8) is converted into axial air and blown towards the heat dissipation surface of the bearing; a slip ring cover (10) is also fixedly connected to the connecting flange (6); a collector ring (11) is sleeved on the output shaft (502), and the internal winding (501) is connected to the collector ring (11) through the output shaft (502) via a line; a brush holder (12) is fixedly connected to the slip ring cover (10), and the brush holder (12) is located on the outer periphery of the collector ring (11).

2. The dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: The air cooler (2) includes a centrifugal fan and an axial fan, with the cooler outlet on the left and the regenerative air outlet on the right.

3. The dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: A cooling airflow path is formed between the stiffeners of the base (1) and the stator core (302), flowing from the left side to the right side of the ventilation channel in the middle of the stiffener, carrying away the heat generated by the motor winding stator (3).

4. The dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: Ventilation holes are provided on the left end cover (401) and right end cover (405) of the rotor. The built-in fan (406) rotates synchronously with the intermediate permanent magnet rotor (4) and draws the cold air output by the air cooler (2) into the cavity of the intermediate permanent magnet rotor (4). The air is discharged from the ventilation hole of the right end cover (405) of the rotor through the shaft rib sleeve of the output shaft (502) and takes away the heat generated by the speed regulating winding rotor (5).

5. The dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: The external fan (8) rotates synchronously with the output shaft (502). The air inlet of the external fan (8) is the central through hole and the bottom air inlet of the slip ring cover (10). The centrifugal air carries away the heat and accumulated carbon powder inside the slip ring cover (10) and blows it to the bearing heat dissipation surface at the same time to reduce the bearing temperature.

6. The dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: The output shaft (502) of the speed regulating winding rotor (5) is rotatably supported on the base (1) by bearings (13), bearings (14) and bearings (18).

7. The dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: The left end cover (401) and right end cover (405) of the intermediate permanent magnet rotor (4) are rotatably supported on the base (1) by bearings (15), bearings (16) and bearings (17).

8. A dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to any one of claims 1 to 7, characterized in that: during operation... The process includes the following steps: energizing the working winding (301) to generate a rotating electromagnetic field; coupling with the permanent magnetic field of the outer permanent magnet group (403) of the intermediate permanent magnet rotor (4) to drive the intermediate permanent magnet rotor (4) to form a synchronous speed; the internal winding (501) cuts the magnetic lines of force of the inner permanent magnet group (404) to generate induced electromotive force and induced current, and controlling the magnitude of the induced current can control the output speed of the speed regulating winding rotor (5); during speed regulation operation, the current of the internal winding (501) is connected to the control system through the collector ring (11).

9. A dual permanent magnet rotor speed-regulating motor with a multi-airflow heat dissipation structure according to claim 1, characterized in that: The stator core (302) is provided with a stator core ventilation channel (3021), and the output shaft (502) is provided with a shaft rib sleeve ventilation channel (5021).

Images