Direct-drive electro-magnetic annular synchronous motor

Abstract

The utility model discloses a direct-drive electro-magnetic annular synchronous motor, and belongs to the technical field of large-scale synchronous motors. The motor comprises a split stator which is formed by splicing and fixing a plurality of stator petals along the circumferential direction; the block magnetic poles form a motor rotor, a plurality of independently-formed magnetic pole units are arranged at intervals in the circumferential direction, and each magnetic pole unit is directly and fixedly installed on the outer wall of the load rotating cylinder; the supporting and sealing structure is arranged at the axial end part between the split stator and the block magnetic pole and is used for sealing a gap between the split stator and the block magnetic pole; and the collector ring and brush carrier system is arranged at one axial end of the motor, and the output end of the collector ring and brush carrier system is electrically connected with the excitation windings of the block magnetic poles. According to the utility model, the split stator and the block magnetic pole structure are adopted, so that the transportation and field installation of the ultra-large motor are facilitated; the rotor is directly mounted on the outer wall of the milling cylinder to realize direct drive, a gear transmission link is omitted, the transmission efficiency is high, and operation is stable; a multi-layer sealing structure adapts to a high-dust environment, and the reliability is high; the speed regulation performance is good and the maintenance is convenient.

Description

Technical Field

[0001] This utility model relates to the field of large synchronous motor technology, and more specifically to a direct-drive electrically excited ring synchronous motor. Background Technology

[0002] As global mineral resource development extends to low-grade ores, mining mills are developing towards higher power, larger volume, higher ball loading, higher efficiency, and energy saving. The gearless direct drive technology of ultra-large mills has become the industry's first choice. The mechanical shaft power of such mills is usually 20MW to 50MW, the speed is 9 to 20 rpm, and they need to be operated in conjunction with frequency conversion speed regulation.

[0003] Traditional mill drives use gear transmission, which has many technical drawbacks: the long transmission chain leads to complex equipment structure and large footprint; gear meshing generates significant noise and vibration, resulting in poor operational stability; the start-up phase causes a significant impact on the power grid and equipment, and the speed regulation performance is poor; gears are prone to wear, resulting in a large workload and high cost of equipment maintenance, and the overall transmission efficiency is low.

[0004] Existing technologies include direct-drive solutions for mills using toroidal motors. However, these motors are ill-suited for the on-site installation conditions of large mills, and their sealing reliability, operational stability, and ease of maintenance do not meet the high standards required for industrial applications, particularly given the harsh working conditions of high dust levels at mill sites. Therefore, designing a highly reliable and efficient direct-drive electrically excited toroidal synchronous motor suitable for mill operating conditions is a pressing technical problem that needs to be solved in this field. Utility Model Content

[0005] This utility model addresses the shortcomings of existing technologies by providing a direct-drive electrically excited ring synchronous motor. Through the structural design of a segmented stator and segmented magnetic poles, it solves the problems of transporting and installing ultra-large motors on-site. It adopts a direct-drive structure without independent bearings, eliminating intermediate transmission components and improving transmission efficiency. Combined with a multi-layer sealing structure and a dedicated excitation power supply system, it is suitable for the harsh working conditions of mill sites, achieving stable, reliable, and low-maintenance operation of the motor and overcoming the technical defects of existing direct-drive motors.

[0006] To achieve the above objectives, this utility model provides a direct-drive electrically excited ring synchronous motor, comprising:

[0007] The segmented stator is composed of multiple stator segments joined and fixed circumferentially, forming an overall ring shape. The joint surfaces between the stator segments are fastened together with bolts and pins.

[0008] The segmented magnetic poles form the motor rotor. The segmented magnetic poles are composed of multiple independently formed magnetic pole units arranged at equal intervals along the circumference. Each magnetic pole unit is directly fixedly installed on the outer wall of the load rotating cylinder.

[0009] A support and sealing structure is provided at the axial end between the segmented stator and the segmented magnetic poles to seal the gap between the segmented stator and the segmented magnetic poles;

[0010] The slip ring and brush holder system is fixedly installed at one axial end of the motor, and the output end of the slip ring and brush holder system is electrically connected to the excitation winding of the segmented magnetic poles.

[0011] This utility model provides a direct-drive electrically excited toroidal synchronous motor, which adopts a segmented stator and segmented magnetic pole structure, disassembling the large motor into multiple modules. This significantly reduces the size and weight of individual components, solving the problem of overall transportation and hoisting of large toroidal motors. Furthermore, the joint surfaces are fastened with bolts and pins, ensuring the overall structural strength and concentricity after assembly. The segmented magnetic poles are directly fixed to the rotating cylinder of the load, achieving a bearingless direct-drive structure and simplifying the transmission chain. The support and sealing structure effectively isolates the motor from the harsh internal and external environments, ensuring reliable motor operation. The slip ring and brush holder system provides reliable current input to the rotor excitation winding.

[0012] Furthermore, the motor has a bearingless structure, with its rotor directly fixed to the outer wall of the load rotating cylinder via the segmented magnetic poles. This bearingless structure further simplifies the overall motor structure.

[0013] Furthermore, the segmented stator includes:

[0014] The stator frame is welded from steel plates.

[0015] The stator core is made of stacked cold-rolled silicon steel sheets and fastened to the stator frame by tensioning screws;

[0016] The stator coil is made of copper flat wire wound in the slots of the stator core, and is an independently formed double-layer wave winding structure.

[0017] This structure ensures that the stator has sufficient mechanical strength and good electromagnetic performance, and the double-layer wave winding facilitates segmented manufacturing and field connection.

[0018] Furthermore, the magnetic pole unit of the segmented magnetic pole includes:

[0019] The magnetic pole core is made of multiple 1.5mm thick cold-rolled steel plates stacked together and fastened together by axial tension screws;

[0020] A magnetic pole coil is made of copper flat wire spirally wound around the pole body of the magnetic pole core, and the magnetic pole coil is covered with an insulating layer.

[0021] The damping winding is disposed on the pole shoe of the magnetic pole core and is composed of a damping rod and a damping ring connected together.

[0022] The mounting plate is a steel plate structure and is fixedly connected between the magnetic pole core and the outer wall of the load rotating cylinder.

[0023] The magnetic pole unit has a compact structure. The stacked iron core and tension screw ensure the mechanical strength of the magnetic pole, the damping winding can effectively suppress the oscillation and reduce harmonics during motor operation, and the mounting plate provides a reliable fixing interface with the grinding cylinder.

[0024] Furthermore, the mounting plate has 2-3 mounting holes, which are fastened to the mounting flange surface of the load rotating cylinder by ultra-tight fit bolts. The ultra-tight fit bolt connection can effectively resist the huge vibration and impact torque generated during mill operation, ensuring that the magnetic pole unit does not loosen or shift during long-term operation.

[0025] Furthermore, the support and sealing structure includes a hard seal and a soft seal disposed between the axial end cover and the housing connection surface. The hard seal is a double-layer metal gasket seal, and the soft seal is an upper and lower layer of rubber sealing rings. The hard seal and the soft seal cooperate to form a multi-layer sealing barrier. This combined sealing structure combines the high temperature resistance and aging resistance of metal seals with the good elasticity and excellent sealing effect of rubber seals, forming multiple layers of protection, significantly improving the protection level of the motor, and effectively preventing external dust and moisture from entering the motor.

[0026] Furthermore, the slip ring and brush holder system includes:

[0027] The slip ring, consisting of a positive and a negative electrode, is fixed to a sealed inner cover that rotates with the rotor by a mounting ring.

[0028] Two sets of brushes are provided, which are fixed to the brush holder on the side of the end cover by insulating rods and slide in close contact with the surface of the slip ring.

[0029] The collector ring and brush holder system are separated from the segmented stator and the segmented magnetic poles by an isolation plate.

[0030] By isolating the slip ring and brush holder system from the main motor cavity using an isolation plate, carbon powder generated by brush wear can be effectively prevented from entering the stator-rotor air gap, affecting insulation performance, and improving the cleanliness and operational reliability of the system.

[0031] Furthermore, the segmented stator is composed of four stator segments symmetrically assembled circumferentially. The four-segment symmetrical structure has good manufacturability, facilitates hoisting and on-site assembly, and the symmetrical structure helps ensure the roundness after assembly.

[0032] Furthermore, it also includes an air-water cooler, which is fixedly installed at the bottom or side of the segmented stator, and its air duct is connected to the inside of the motor; the air-water cooler realizes heat exchange inside the motor and effectively controls the temperature rise of the motor.

[0033] Furthermore, two air-water coolers are provided, and the motor adopts IC86W forced air cooling. Air-water composite cooling is achieved through the air-water coolers, with the cooling medium circulating between the motor and the air-water coolers for heat dissipation. The dual-cooler design and IC86W cooling method ensure effective heat dissipation for large motors, suitable for high-load, continuous operation conditions.

[0034] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0035] 1. Solving the challenges of transporting and installing ultra-large motors: The segmented stator and segmented magnetic pole structure enable the motor to be manufactured separately, transported independently, and assembled on-site. The parts have good machinability, and after assembly, they are fastened with bolts and pins, ensuring the overall structural strength and concentricity of the motor, making it suitable for the on-site installation conditions of large mills.

[0036] 2. Improve transmission efficiency and operational stability: The rotor magnetic poles are directly fixed to the outer wall of the load rotating cylinder, realizing integrated direct drive of the motor and load, completely eliminating intermediate transmission links and significantly improving system transmission efficiency; at the same time, it eliminates the noise and vibration caused by gear meshing, reduces the impact of equipment startup on the power grid and equipment, and is suitable for the variable frequency speed regulation operation requirements of the mill.

[0037] 3. Adaptable to harsh working conditions with high dust: The support and sealing structure adopts a multi-layer sealing form that combines hard and soft seals, which can effectively block dust at the mill site, prevent dust from entering the air gap between the stator and rotor and causing friction and wear, ensure the cleanliness of the motor interior, and greatly improve the reliability of the motor operation under high dust conditions.

[0038] 4. Excellent speed regulation performance and convenient maintenance: The brushed excitation method is adopted, and the excitation current is stably transmitted through the slip ring and brush holder system. The excitation current is flexibly adjustable and the motor speed regulation performance is excellent. In addition, the system has a compact structure, is easy to install and maintain, and reduces equipment operation and maintenance costs.

[0039] 5. Simplified structure and reduced manufacturing costs: The motor adopts a bearingless structure, making full use of the supporting role of the rotating cylinder under load, simplifying the overall structural design of the motor, reducing the number of parts, and effectively reducing manufacturing costs.

[0040] 6. Meets long-term heavy-load heat dissipation requirements: The air-water cooler achieves air-water composite cooling, which has high cooling efficiency and can quickly remove the heat generated by the motor operation, keeping the motor operating temperature within the rated range and meeting the heat dissipation requirements of the motor for long-term heavy-load continuous operation.

[0041] 7. Further improve operational stability: The damping winding of the segmented magnetic poles can effectively suppress oscillations during motor operation, reduce harmonic interference, avoid motor instability, and ensure continuous and stable operation of the mill. Attached Figure Description

[0042] This utility model will be described by way of example and with reference to the accompanying drawings, wherein:

[0043] Figure 1 This is a front view schematic diagram of the external shape of the electrically excited ring synchronous motor in the embodiment of this utility model;

[0044] Figure 2 yes Figure 1 A schematic diagram of the right-side view structure;

[0045] Figure 3 yes Figure 2 Schematic diagram of the internal AA cross-sectional structure of the Zhongdian excitation ring synchronous motor;

[0046] Figure 4 yes Figure 3 Cross-sectional view of the segmented magnetic poles (BB) of a medium-powered excitation ring synchronous motor;

[0047] Figure 5 yes Figure 3 Enlarged schematic diagram of the central support and seal at point C;

[0048] The diagram is labeled as follows: 1-segmented stator, 11-stator frame, 12-stator core, 13-stator coil, 2-segmented magnetic pole, 21-damping rod, 22-damping ring, 23-magnetic pole coil, 24-mounting plate, 25-magnetic pole core, 3-isolation plate, 4-slip ring and brush holder system, 41-slip ring, 42-brush, 43-brush holder, 5-support and sealing structure, 51-hard seal, 52-soft seal, 53-axial end cap, 54-shell, 6-load rotating cylinder, 7-air-water cooler. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0051] like Figure 1-5 As shown, this embodiment provides a direct-drive electrically excited ring synchronous motor with an overall ring structure. The core includes a segmented stator 1, segmented magnetic poles 2, a support and sealing structure 5, a slip ring and brush holder system 4, and an air-water cooler 7. The motor has no independent bearings and is directly connected to the load rotating cylinder 6 to achieve gearless direct drive. The load rotating cylinder 6 is, for example, but not limited to, a mill grinding cylinder.

[0052] The segmented stator 1 is composed of four stator segments symmetrically assembled and fixed along the circumference, forming an overall ring shape. The splicing surfaces between the stator segments are secured with high-strength bolts and pins. After disassembly, it is compact in size, making it easy to transport over long distances. After on-site assembly, it ensures the overall concentricity and structural strength of the stator.

[0053] Each stator segment includes a stator frame 11, a stator core 12, and a stator coil 13. The stator frame 11 is welded from steel plates and undergoes stress relief treatment after welding, resulting in high structural strength and serving as the supporting carrier for the entire stator. The stator core 12 is made of stacked cold-rolled silicon steel sheets and fastened with tension screws. It is the main magnetic conductive component of the motor, effectively reducing iron loss and improving magnetic conductivity. The stator coil 13 is wound with copper flat wire in a double-layer wave winding form. It is wound in the slots of the stator core 12, and after vacuum pressure impregnation, it is independently formed, ensuring reliable insulation performance and adaptability to high-voltage power supply conditions. The winding has excellent heat dissipation performance. After the stator coil 13 arrives at the site, it is assembled, connected, and wound.

[0054] The segmented magnetic poles 2 constitute the rotor of the motor. Multiple independently formed magnetic pole units are arranged at equal intervals along the circumference on the outer wall of the load rotating cylinder 6. The motor has no independent bearings and achieves synchronous rotation with the grinding cylinder by relying on the rigid fixed connection between the segmented magnetic poles 2 and the load rotating cylinder 6.

[0055] like Figure 3 and Figure 4As shown, each magnetic pole unit includes a magnetic pole core 25, a magnetic pole coil 23, a damping winding, and a mounting plate 24. The magnetic pole core 25 is made of multiple 1.5mm thick cold-rolled steel plates stacked together and fastened by axial tension screws. The magnetic pole coil 23 is made of copper flat wire spirally wound on the pole body of the magnetic pole core 25 and is insulated. The damping winding is set on the pole shoe of the magnetic pole core 25 and is composed of a damping rod 21 and a damping ring 22. It is used to suppress oscillations and reduce harmonics during motor operation and improve operational stability. The mounting plate 24 is a thick steel plate structure, which is fixedly connected between the magnetic pole core 25 and the outer wall of the load rotating cylinder 6. The mounting plate 24 has two or three mounting holes pre-machined. When the magnetic pole is mounted, it is hinged according to the actual working conditions to ensure tight circumferential fit and concentric outer circle. Then, it is fixed to the mounting flange surface of the load rotating cylinder 6 by ultra-tight fitting bolts, realizing the direct integrated connection between the rotor and the load. The ultra-tight fitting bolts are hinged on site and then tightened by interference fit.

[0056] Support and sealing structure 5: Designed to address the harsh working conditions of high dust levels at the mill site, a support and sealing structure 5 is installed at the axial end between the segmented stator 1 and the segmented magnetic poles 2. This structure employs an independent elastic design, such as... Figure 3 and Figure 5 As shown, it includes a hard seal 51 and a soft seal 52, both of which are disposed between the axial end cover 53 and the housing 54 connecting surface.

[0057] The hard seal 51 is a metal gasket seal with a double-layer structure, which undertakes the main sealing function and bears axial pressure; the soft seal 52 is a rubber sealing ring with an upper and lower layer structure, which works with the double-layer hard seal to form a multi-layer sealing barrier, effectively preventing external dust from entering the stator and rotor air gap inside the motor, avoiding friction and wear between the magnetic poles and the stator, and is suitable for dusty industrial conditions such as mining and cement.

[0058] The slip ring and brush holder system 4 is set at one end of the motor shaft to achieve rotor excitation. This system is separated from the segmented stator 1 and the segmented magnetic poles 2 by the isolation plate 3 to prevent dust from entering the system and affecting the excitation transmission.

[0059] like Figure 3 As shown, the slip ring and brush holder system 4 includes a slip ring 41 and brushes 42: the slip ring 41 has a positive and a negative pole, which is fixed to the sealed inner cover that rotates with the rotor by a mounting ring and rotates synchronously with the rotor; the brushes 42 are provided in two sets, which are fixed to the brush holder 43 on the side of the end cover by insulating rods. The ends of the brushes 42 are in close sliding contact with the surface of the slip ring 41. Through mechanical commutation, the external excitation voltage and excitation current are stably introduced into the rotating rotor magnetic pole coil 23 to realize motor excitation and ensure the stability of excitation current transmission.

[0060] Air-water cooler 7: In this embodiment, the motor adopts IC86W forced air cooling, and air-water composite cooling is achieved through air-water cooler 7. Figure 1-2 As shown, there are two air-water coolers 7, which are fixedly installed at the bottom or side of the split stator 1, and their air ducts are connected to the inside of the motor.

[0061] The primary cooling medium inside the motor is air, which carries away the heat generated by the motor during circulation. The hot air enters the air-water cooler 7 through the air duct, where it exchanges heat with the secondary cooling medium, cooling water, and is then cooled down. The cooled air re-enters the motor, forming a circulating heat dissipation system with high efficiency. This system can meet the heat dissipation requirements of the motor during long-term heavy-load continuous operation and keep the motor operating temperature within the rated reasonable range.

[0062] Assembly and operation process of this utility model:

[0063] Stator assembly: Transport each stator segment of the segmented stator 1 to the site, assemble them symmetrically in an up-down and left-right manner, and fix them in place by bolts and pins to complete the overall stator assembly;

[0064] Rotor assembly: Connect each magnetic pole unit to the mounting flange surface of the load rotating cylinder 6 in sequence through the mounting plate 24. After fitting the mounting holes, use super-tight bolts and pins to tighten them. Adjust the circumferential spacing of the magnetic pole units to ensure concentricity and complete the rotor assembly.

[0065] Auxiliary component assembly: Install support and sealing structure 5 at the axial ends of the segmented stator 1 and segmented magnetic pole 2, install slip ring and brush holder system 4 at one axial end of the motor, fix air-water cooler 7 at the bottom of segmented stator 1, and complete the installation of isolation plate 3.

[0066] Wiring and debugging: Connect the stator power supply line, excitation line and cooling system pipeline to complete the wiring and debugging of the whole machine, and it can be put into use.

[0067] Operating principle: Stator coil 13 is connected to three-phase high-voltage AC power to generate a rotating magnetic field; the segmented magnetic poles 2 form a constant magnetic field under the action of excitation current. The rotating magnetic field and the constant magnetic field interact to generate electromagnetic torque, which directly drives the load rotating cylinder 6 to rotate, realizing gearless direct drive operation.

[0068] During operation, the multiple sealing barriers of the support and sealing structure 5 effectively block external dust, the air-water cooler 7 achieves efficient heat dissipation of the motor, the damping winding suppresses motor oscillation and reduces harmonics, and the slip ring and brush holder system 4 ensures stable transmission of excitation current. All components work together to enable the motor to achieve efficient, stable, reliable, and low-maintenance operation.

[0069] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the concept of this utility model and the contents of the specification and drawings of this utility model, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model.

Claims

1. A direct-drive electrically excited toroidal synchronous motor, characterized in that, include: The segmented stator (1) is composed of multiple stator segments joined and fixed together circumferentially, and the joint surfaces between the stator segments are fastened together with bolts and pins. The segmented magnetic poles (2) form the motor rotor. The segmented magnetic poles (2) are formed by multiple independently formed magnetic pole units arranged at equal intervals along the circumference. Each magnetic pole unit is directly fixed to the outer wall of the load rotating cylinder (6). A support and sealing structure (5) is provided at the axial end between the segmented stator (1) and the segmented magnetic pole (2) to seal the gap between the segmented stator (1) and the segmented magnetic pole (2); The slip ring and brush holder system (4) is fixedly installed at one end of the axial direction of the motor, and the output end of the slip ring and brush holder system (4) is electrically connected to the excitation winding of the segmented magnetic pole (2).

2. The direct-drive electrically excited ring synchronous motor according to claim 1, characterized in that, The motor has a structure without independent bearings, and its rotor is supported by the fixed connection between the segmented magnetic poles (2) and the outer wall of the load rotating cylinder (6).

3. The direct-drive electrically excited ring synchronous motor according to claim 1, characterized in that, The segmented stator (1) includes: The stator frame (11) is formed by welding steel plates; The stator core (12) is made of stacked cold-rolled silicon steel sheets and fastened to the stator frame (11) by tensioning screws; The stator coil (13) is made of copper flat wire wound in the slot of the stator core (12) and is an independently formed double-layer wave winding structure.

4. The direct-drive electrically excited ring synchronous motor according to claim 1, characterized in that, The magnetic pole units of the segmented magnetic poles (2) include: The magnetic pole core (25) is made of multiple 1.5mm thick cold-rolled steel plates stacked together and fastened by axial tension screws; The magnetic pole coil (23) is made of copper flat wire spirally wound on the pole body of the magnetic pole core, and the magnetic pole coil (23) is covered with an insulating layer. The damping winding is disposed on the pole shoe of the magnetic pole core and is composed of a damping rod (21) and a damping ring (22). The mounting plate (24) is a steel plate structure and is fixedly connected between the magnetic pole core (25) and the outer wall of the load rotating cylinder (6).

5. The direct-drive electrically excited ring synchronous motor according to claim 4, characterized in that, The mounting plate (24) has 2-3 mounting holes, which are fastened to the mounting flange of the load rotating cylinder (6) by super-tightening bolts.

6. The direct-drive electrically excited ring synchronous motor according to claim 1, characterized in that, The support and sealing structure (5) includes a hard seal (51) and a soft seal (52) disposed between the axial end cap (53) and the housing (54) connection surface. The hard seal (51) is a double-layer metal gasket seal, and the soft seal (52) is an upper and lower layer rubber sealing ring. The hard seal (51) and the soft seal (52) cooperate to form a multiple sealing barrier.

7. The direct drive electrically excited ring-shaped synchronous motor according to claim 1, characterized in that, The slip ring and brush holder system (4) includes: The slip ring (41) includes a positive and a negative electrode and is fixed to the sealed inner cover that rotates with the rotor by a mounting ring; Two sets of brushes (42) are fixed to the brush holder (43) on the side of the end cover by insulating rods and slide in close contact with the surface of the slip ring (41). The collector ring and brush holder system (4) is separated from the segmented stator (1) and the segmented magnetic poles (2) by an isolation plate (3).

8. The direct drive electrically excited ring-shaped synchronous motor according to claim 1, characterized by The segmented stator (1) is composed of four stator segments symmetrically joined together along the circumference, both vertically and horizontally.

9. The direct-drive electrically excited ring synchronous motor according to claim 1, characterized in that, It also includes an air-water cooler (7), which is fixedly installed at the bottom or side of the segmented stator (1), and its air duct is connected to the inside of the motor.

10. The direct-drive electrically excited ring synchronous motor according to claim 9, characterized in that, Two air-water coolers (7) are provided. The motor adopts IC86W forced air cooling method. Air-water composite cooling is achieved through the air-water coolers (7). The cooling medium forms a circulation heat dissipation between the motor and the air-water coolers (7).

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