A radial-axial active magnetic bearing for electric machines

Abstract

The application discloses a radial-axial active magnetic suspension bearing suitable for a motor, which is composed of a series of components such as a left end cover, a radial magnetic suspension bearing rotor, a radial magnetic suspension bearing stator coil, a radial magnetic suspension bearing outer race, an axial displacement sensor detection ring, a radial-axial sensor assembly, a radial displacement sensor detection ring, an axial magnetic suspension bearing rotor thrust disc, an axial magnetic suspension bearing stator I, an axial magnetic suspension bearing stator II, an axial magnetic suspension bearing outer race right end cover, an auxiliary protection bearing axial positioning adjusting sleeve I, an auxiliary protection bearing, an auxiliary protection bearing seat, an auxiliary protection bearing axial positioning adjusting sleeve II and a radial-axial magnetic suspension bearing inner race. The magnetic suspension bearing has the characteristics of high rotating speed, can greatly improve the working efficiency of the motor, has the upgrading and replacement effect on the traditional motor, has a long service life, is pollution-free and meets the double-carbon requirement.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of magnetic suspension bearings, and specifically relates to a radial-axial active magnetic suspension bearing suitable for a motor. BACKGROUND

[0002] The active magnetic suspension bearing system can provide a mechanical contact-free supporting force and has no mechanical friction, completely eliminates bearing heating and lubrication pollution problems caused thereby, is suitable for high-speed rotation occasions, and the supporting force of the active magnetic suspension bearing is controllable within a certain range. The active magnetic suspension bearing can be applied to an aero-engine and a micro gas turbine generator, can greatly improve the operation efficiency of the machine, and can effectively reduce the energy consumption in operation. The controllability of the active magnetic suspension bearing system makes the motor more stable during operation, has a longer service life, and is safer when passing through a critical speed.

[0003] At present, the magnetic suspension bearing is rarely applied to the aero-engine and the micro gas turbine generator at home and abroad. The successful application of the magnetic suspension bearing to the aero-engine and the micro gas turbine generator can make a new contribution to the supporting technology of the aero-engine and the gas turbine generator and fill the domestic blank. SUMMARY

[0004] The radial-axial active magnetic suspension bearing suitable for the motor can improve the operation efficiency of the motor, has an upgrading effect on the traditional motor, has a long service life, has no pollution, and meets the double-carbon requirement.

[0005] To achieve the above-mentioned purpose, the application adopts the following technical scheme:

[0006] A radial-axial active magnetic suspension bearing for a motor, comprising a left end cover, an outer race, a right end cover and an inner race. Its features are that a radial magnetic suspension bearing rotor and a radial magnetic suspension bearing stator coil are installed on the left side of the inner cavity of the outer race, and a radial-axial sensor assembly is installed on the right side, while the right end cover is internally provided with an axial magnetic suspension bearing stator I and an axial magnetic suspension bearing stator II, which contain stator coils. The right side of the right end cover is connected to an auxiliary protection bearing seat, and the auxiliary protection bearing seat is internally provided with an auxiliary protection bearing. An axial displacement sensor detection ring, a radial displacement sensor detection ring and an axial magnetic suspension bearing rotor thrust disc are installed between the radial magnetic suspension bearing rotor and the axial magnetic suspension bearing stator II.

[0007] The radial magnetic suspension bearing rotor is stably suspended together by controllable magnetic radial attraction generated by the radial magnetic suspension bearing stator coil without contact, combined into a radial magnetic suspension bearing system and installed in the radial magnetic suspension bearing outer race. The radial-axial sensor assembly is a radial-axial sensor system composed of radial sensors and axial sensors installed on the radial-axial displacement sensor seat and bolted next to the radial magnetic suspension bearing system on the right side of the radial magnetic suspension bearing outer race, and the axial magnetic suspension bearing system is on the right side. The axial magnetic suspension bearing rotor thrust disc is stably suspended together by controllable magnetic axial attraction generated by the axial magnetic suspension bearing stator I and the axial magnetic suspension bearing stator II containing stator coils without contact, combined into an axial magnetic suspension bearing system and installed in the axial magnetic suspension bearing outer race right end cover. The auxiliary protection bearing is composed of two sets of high-speed angular contact ball bearings installed face to face into a radial-axial protection bearing system, with the inner ring of the radial-axial protection bearing system loosely fitted on the radial-axial magnetic suspension bearing inner race and the outer ring installed in the auxiliary protection bearing seat. The radial gap between the inner ring loosely fitted on the inner race and the outer ring is smaller than the gap between the radial magnetic suspension bearing stator and its radial magnetic suspension bearing rotor, which serves as protection, while the axial positioning adjustment sleeve I and the axial positioning adjustment sleeve II are separately and axially loosely fitted on the radial-axial magnetic suspension bearing inner race with a gap on both sides of the inner ring of the radial-axial protection bearing system, and the axial gap is smaller than the gap between the axial magnetic suspension bearing and its axial rotor thrust disc, which serves as protection, combined into an auxiliary protection bearing system. The radial magnetic suspension bearing rotor, radial displacement sensor detection ring, axial displacement sensor detection ring and axial magnetic suspension bearing rotor thrust disc are loosely fitted on the radial-axial magnetic suspension bearing inner race in the same way as the auxiliary protection bearing axial positioning adjustment sleeve I and the auxiliary protection bearing axial positioning adjustment sleeve II, combined into a radial-axial magnetic suspension bearing inner race rotor system. The left end cover, radial magnetic suspension bearing outer race, axial magnetic suspension bearing outer race right end cover and auxiliary protection bearing seat are fixedly connected together by countersunk head bolts, combined into a radial-axial magnetic suspension bearing outer race stator system.

[0008] After the main rotor shaft is installed inside the inner ring of the radial-axial magnetic levitation bearing, in the stationary state, the weight of the main rotor system is borne by the paired auxiliary protective bearings installed at both ends. In the working state, the radial magnetic levitation bearing stator coil, axial magnetic levitation bearing stator I, and axial magnetic levitation bearing stator II, all installed in the stator system of the outer ring of the radial-axial magnetic levitation bearing, and stator I and stator II (which contain stator coils), generate a rapid increase in radial and axial electromagnetic forces, causing the rotor system of the inner ring of the radial-axial magnetic levitation bearing to immediately float to the initial bias position. After reaching the initial position, the support... The rotor system, located on the radial-axial magnetic levitation bearing inner ring, is completely suspended. The inner ring of the auxiliary bearing is no longer in contact with the rotor system. The imbalance between the weight of the main shaft and the axial force of the impellers at both ends is entirely borne by the radial-axial magnetic force generated by the radial magnetic levitation bearing stator coils, axial magnetic levitation bearing stator I, axial magnetic levitation bearing stator II (stator I and stator II contain stator coils), and the radial-axial magnetic levitation bearing outer ring stator system. The external force drives the impellers at both ends to rotate at high speed, which in turn drives the generator rotor to rotate at high speed to generate electricity. When the motor support system is working normally, if an unforeseen accident such as an external overload or power failure occurs, the high-speed rotating rotor system may fall. In this case, to prevent the high-speed rotor system components from rubbing against the magnetic levitation bearing stator and the motor stator, and to prevent the sensors from being damaged by the falling rotor system, the support system should be changed from a magnetic levitation bearing system to an auxiliary protection bearing system. It is necessary to ensure that the rotor system lands on the auxiliary protection bearing when it falls. Given the working air gap value of the radial and axial magnetic bearings (approximately 0.3 mm), the radial and axial protective air gaps of the auxiliary bearings (both 0.15~0.2 mm) are designed to be smaller than the working air gap value of the radial and axial magnetic bearings (approximately 0.3 mm). This can prevent collisions, rubbing, and other damage events with the magnetic bearings. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the radial-axial active magnetic levitation bearing structure for motors described in this invention.

[0010] Figure 2 This is a three-dimensional model diagram of the radial-axial active magnetic levitation bearing described in this invention.

[0011] Figure 3 This is a three-dimensional model diagram of the radial active magnetic levitation bearing described in this invention.

[0012] Figure 4 This is a three-dimensional model diagram of the axial active magnetic levitation bearing described in this invention.

[0013] Figure 5 This is a three-dimensional model diagram of the radial-axial active magnetic levitation bearing sensor described in this invention.

[0014] Figure 6 Figure 3 is a three-dimensional model diagram of the auxiliary protection bearing according to the present application. DETAILED DESCRIPTION

[0015] The specific implementation of the present application will be described in detail below with reference to the accompanying drawings. Example One

[0016] Reference Figure 1 The radial-axial active magnetic suspension bearing for the motor comprises a left end cover 1, an outer race 4, a right end cover 11, and an inner race 16. The radial-axial active magnetic suspension bearing is characterized in that a radial magnetic suspension bearing rotor 2 and a radial magnetic suspension bearing stator coil 3 are arranged on the left side of the inner cavity of the outer race 4, a radial-axial sensor assembly 6 is arranged on the right side of the outer race 4, an axial magnetic suspension bearing stator I 9 and an axial magnetic suspension bearing stator II 10 are arranged in the right end cover 11, the stator I 9 and the stator II 10 contain stator coils, an auxiliary protection bearing seat 14 is connected to the right side of the right end cover 11, an auxiliary protection bearing 13 is arranged in the auxiliary protection bearing seat 14, an axial displacement sensor detection ring 5, a radial displacement sensor detection ring 7, and an axial magnetic suspension bearing rotor thrust disc 8 are arranged between the radial magnetic suspension bearing rotor 2 and the axial magnetic suspension bearing stator II 10.

[0017] The radial-axial active magnetic suspension bearing for the motor improves the working efficiency of the motor, has the effect of upgrading the traditional motor, has a long service life, does not pollute the environment, and meets the double-carbon requirements. Example Two

[0018] The example is basically the same as example one, and the special features are as follows:

[0019] The radial magnetic suspension bearing rotor 2 is stably suspended and supported together by controllable magnetic radial attraction generated by the radial magnetic suspension bearing stator coil 3 without contact, and is combined into a radial magnetic suspension bearing system and arranged in the outer race 4.

[0020] The radial-axial sensor assembly 6 is a radial-axial sensor system combined by arranging a radial sensor 6I and an axial sensor 6II on a radial-axial displacement sensor seat 6III and fixing them to the right side of the radial magnetic suspension bearing system in the outer race 4 of the radial magnetic suspension bearing system by bolts, and the axial magnetic suspension bearing system is arranged to the right of the radial-axial sensor system.

[0021] The axial magnetic suspension bearing rotor thrust disc 8 is stably suspended and supported together by controllable magnetic axial attraction generated by the axial magnetic suspension bearing stator I 9 and the axial magnetic suspension bearing stator II 10 without contact, and is combined into an axial magnetic suspension bearing system and arranged in the right end cover 11. The stator I 9 and the stator II 10 contain stator coils.

[0022] The auxiliary protection bearing 13 is composed of two sets of high-speed angular contact ball bearings installed face to face to form a radial-axial protection bearing system, the inner ring of which is loosely sleeved on the inner shaft ring 16, and the outer ring is installed in the auxiliary protection bearing seat 14, the radial gap between the inner ring loosely sleeved on the inner shaft ring 16 and the radial magnetic suspension bearing stator coil 3 and the radial magnetic suspension bearing rotor 2 is smaller than the gap between the axial magnetic suspension bearing stator I 9 and the stator II 10 and the axial rotor thrust disc 8, which plays a protective role, and the auxiliary protection bearing axial positioning adjusting sleeve I 12 and the axial positioning adjusting sleeve II 15 are fixed on the inner shaft ring 16 with axial clearance on both sides of the inner ring of the radial-axial protection bearing system, and the axial gap between the auxiliary protection bearing axial positioning adjusting sleeve I 12 and the axial positioning adjusting sleeve II 15 and the inner ring of the radial-axial protection bearing system is smaller than the gap between the axial magnetic suspension bearing stator I 9 and the stator II 10 and the axial rotor thrust disc 8, which plays a protective role, and is combined into an auxiliary protection bearing system.

[0023] The radial magnetic suspension bearing rotor 2, the axial displacement sensor detection ring 5, the radial displacement sensor detection ring 7 and the axial magnetic suspension bearing rotor thrust disc 8 are fixed on the inner shaft ring 16 with the auxiliary protection bearing axial positioning adjusting sleeve I 12 and the axial positioning adjusting sleeve II 15, which form a radial-axial magnetic suspension bearing inner shaft ring rotor system.

[0024] The left end cover 1, the outer ring 4, the right end cover 11 and the auxiliary protection bearing seat 14 are fixedly connected together by countersunk head bolts to form a radial-axial magnetic suspension bearing outer ring stator seat system.

[0025] In this embodiment, the radial and axial sensors are integrated into a one-piece radial-axial sensor, the radial active magnetic bearing, the axial active magnetic bearing and the radial-axial sensor, and the auxiliary protection bearing are integrated into a one-piece radial-axial active magnetic suspension bearing, which can replace mechanical bearings in motors (electric motors, generators and motor generators). The active magnetic suspension bearing uses control current to control the attractive force generated by the electromagnetic poles on the rotor system to achieve non-contact stable suspension of the rotor, with a maximum working speed of 2.5 times that of sliding bearings and 5 times that of rolling bearings, and has the characteristics of high speed, which can greatly improve the working efficiency of the motor, has the effect of upgrading and replacing the traditional motor, and has a long service life and no pollution, which meets the double carbon requirements.

[0026] Example Three:

[0027] Referring to Figure 1A radial-axial active magnetic suspension bearing for a motor is composed of a left end cover 1, a radial magnetic suspension bearing rotor 2, a radial magnetic suspension bearing stator coil 3, a radial magnetic suspension bearing outer race 4, an axial displacement sensor probe ring 5, a radial-axial sensor assembly 6, a radial displacement sensor probe ring 7, an axial magnetic suspension bearing rotor thrust disc 8, an axial magnetic suspension bearing stator I 9, an axial magnetic suspension bearing stator II 10 (the stator I 9 and the stator II 10 contain stator coils), an axial magnetic suspension bearing outer race right end cover 11, an auxiliary protection bearing axial positioning adjusting sleeve I 12, an auxiliary protection bearing 13, an auxiliary protection bearing seat 14, an auxiliary protection bearing axial positioning adjusting sleeve II 15, a radial-axial magnetic suspension bearing inner race 16 and a series of other components.

[0028] Referring to the drawings Figure 1 to the drawings Figure 6, the radial magnetic suspension bearing rotor 2 is non-contacting stably suspended and supported together by controllable magnetic radial attractive force generated by the radial magnetic suspension bearing stator coils 3, combined into a radial magnetic suspension bearing system, installed in the radial magnetic suspension bearing outer race 4. The radial-axial sensor assembly 6 is the radial sensor 6I and the axial sensor 6II installed on the radial-axial displacement sensor seat 6III and bolted to the radial magnetic suspension bearing system right next to the radial-axial displacement sensor seat 6III in the radial magnetic suspension bearing outer race 4, combined into a radial-axial sensor system, and the axial magnetic suspension bearing system is to the right. The axial magnetic suspension bearing rotor thrust disc 8 is non-contacting stably suspended and supported together by controllable magnetic axial attractive force generated by the axial magnetic suspension bearing stator I 9 and the axial magnetic suspension bearing stator II 10 (the stator I 9 and the stator II 10 contain stator coils), combined into an axial magnetic suspension bearing system, installed in the axial magnetic suspension bearing outer race right end cover 11. The auxiliary protection bearing 13 is composed of two sets of high-speed angular contact ball bearings installed face to face into a radial-axial protection bearing system, the inner ring is loosely fitted on the radial-axial magnetic suspension bearing inner shaft 16, and the outer ring is installed in the auxiliary protection bearing seat 14, the radial gap of the inner ring loosely fitted on the inner shaft 16 is smaller than the gap between the radial magnetic suspension bearing stator coils 3 and the radial magnetic suspension bearing rotor 2, which serves as protection, and the auxiliary protection bearing axial positioning adjustment sleeve I 12 and the auxiliary protection bearing axial positioning adjustment sleeve II 15 are respectively fixed on the radial-axial magnetic suspension bearing inner shaft 16 with axial clearance on both sides of the radial-axial protection bearing system inner ring, the axial clearance between the auxiliary protection bearing axial positioning adjustment sleeve I 12 and the axial positioning adjustment sleeve II 15 and the radial-axial protection bearing system inner ring is smaller than the gap between the axial magnetic suspension bearing stator I 9 and the stator II 10 and the axial rotor thrust disc 8, which serves as protection, combined into an auxiliary protection bearing system. The radial magnetic suspension bearing rotor 2, the axial displacement sensor detection ring 5, the radial displacement sensor detection ring 7 and the axial magnetic suspension bearing rotor thrust disc 8 are fixed on the radial-axial magnetic suspension bearing inner shaft 16 in the same way as the auxiliary protection bearing axial positioning adjustment sleeve I 12 and the axial positioning adjustment sleeve II 15, which constitutes a radial-axial magnetic suspension bearing inner shaft rotor system. The left end cover 1, the radial magnetic suspension bearing outer race 4, the axial magnetic suspension bearing outer race right end cover 11 and the auxiliary protection bearing seat 14 are fixed and connected together by countersunk head bolts to form a radial-axial magnetic suspension bearing outer race stator seat system.

[0029] After the host rotating shaft is installed in the inner ring 16 of the radial-axial magnetic suspension bearing, the gravity of the host rotor system in the stopped and static state is borne by the pair of auxiliary protection bearings 13 installed at both ends; in the working state, the radial and axial electromagnetic forces generated by the radial magnetic suspension bearing stator coils 3, the axial magnetic suspension bearing stator I 9, and the axial magnetic suspension bearing stator II 10 (the stator I 9 and the stator II 10 contain stator coils) installed in the radial-axial magnetic suspension bearing outer ring stator system are rapidly increased so that the radial-axial magnetic suspension bearing inner ring rotor system is immediately floated to the initial bias position, and after reaching the initial position, the radial-axial magnetic suspension bearing inner ring rotor system where the host rotating shaft is located is completely suspended, the inner ring of the auxiliary bearing is no longer in contact with the radial-axial magnetic suspension bearing inner ring rotor system where the host rotating shaft is located, and the balance difference between the gravity of the host rotating shaft and the axial force of the impeller at both ends is completely borne by the radial and axial magnetic forces generated by the radial magnetic suspension bearing stator 3, the axial magnetic suspension bearing stator I 9, the axial magnetic suspension bearing stator II 10 (the stator I 9 and the stator II 10 contain stator coils), and the radial-axial magnetic suspension bearing outer ring stator system, and the external force drives the high-speed rotation of the impeller at both ends to drive the generator rotor to rotate at high speed to generate electricity. When the motor support system is working normally, unexpected accidents such as unknown external overload or power failure will cause the high-speed rotating rotor system to fall, at this time, in order to avoid the sweep bore of the high-speed rotor system components and the sensor from being damaged by the falling rotor system, the support system should be converted from the magnetic suspension bearing system to the auxiliary protection bearing system, and it is necessary to ensure that the rotor system falls on the auxiliary protection bearing when it falls. For the working air gap value (about 0.3mm) of the radial magnetic bearing and the axial magnetic bearing, the radial protection air gap and the axial protection air gap (both are 0.15~0.2mm) of the auxiliary bearing are designed to be smaller than the working air gap value (about 0.3mm) of the radial magnetic bearing and the axial magnetic bearing, so that collision, sweep bore and other damage events with the magnetic bearing can be avoided.

[0030] The above describes the embodiments of the present application in combination with the drawings, but the present application is not limited to the above-described embodiments, and various changes can be made according to the purpose of the invention of the present application. Any change, modification, replacement, combination or simplification made according to the spirit and principles of the technical solution of the present application shall be an equivalent replacement manner, as long as it meets the purpose of the present application, as long as it does not deviate from the technical principles and inventive concept of the present application, and belongs to the protection scope of the present application.

Claims

1. A radial-axial active magnetic levitation bearing suitable for an electric motor, comprising a left end cover (1), an outer race (4), a right end cover (11), and an inner race (16); characterized in that: The radial magnetic bearing rotor (2) and radial magnetic bearing stator coil (3) are installed on the left side of the inner cavity of the outer race (4), and the radial-axial sensor assembly (6) is installed on the right side. The axial magnetic bearing stator I (9) and axial magnetic bearing stator II (10) are installed inside the right end cover (11). The axial magnetic bearing stator I (9) and axial magnetic bearing stator II (10) contain stator coils. An auxiliary protection bearing seat (14) is connected to the right side of the right end cover (11). An auxiliary protection bearing (13) is installed inside the auxiliary protection bearing seat (14). An axial displacement sensor detection ring (5), a radial-axial sensor assembly (6), a radial displacement sensor detection ring (7), and an axial magnetic bearing rotor thrust disk (8) are installed between the radial magnetic bearing rotor (2) and the axial magnetic bearing stator II (10). The radial magnetic levitation bearing rotor (2) is supported together by the controllable radial magnetic attraction generated by the radial magnetic levitation bearing stator coil (3) without contact, forming a radial magnetic levitation bearing system, which is installed in the outer race (4). The radial and axial sensor assembly (6) is a radial and axial sensor system that is mounted on the radial and axial displacement sensor seat and bolted to the radial magnetic levitation bearing system near the outer race (4), and is then combined into a radial and axial sensor system. Further to the right is the axial magnetic levitation bearing system. The axial magnetic levitation bearing rotor thrust disk (8) is supported together by the controllable magnetic axial attraction generated by the axial magnetic levitation bearing stator I (9) and the axial magnetic levitation bearing stator II (10) without contact. The axial magnetic levitation bearing stator I (9) and the axial magnetic levitation bearing stator II (10) contain stator coils and are combined into an axial magnetic levitation bearing system, which is installed in the right end cover (11). The auxiliary protection bearing (13) is a radial-axial protection bearing system composed of two sets of high-speed angular contact ball bearings installed face to face. Its inner ring is loosely fitted on the inner shaft ring (16), and the outer ring is installed in the auxiliary protection bearing housing (14). The radial clearance of the inner ring loosely fitted on the inner shaft ring (16) is smaller than the clearance between the radial magnetic levitation bearing stator coil (3) and its radial magnetic levitation bearing rotor (2), which plays a protective role. The auxiliary protection bearing axial positioning adjustment sleeve I (12) and axial positioning adjustment sleeve II (15) are respectively axially and loosely fitted on the inner shaft ring (16) on both sides of the inner ring of the radial-axial protection bearing system. The axial clearance between the auxiliary protection bearing axial positioning adjustment sleeve I (12) and axial positioning adjustment sleeve II (15) and the inner ring of the radial-axial protection bearing system is smaller than the clearance between the axial magnetic levitation bearing stator I (9) and the axial magnetic levitation bearing stator II (10) and its axial rotor thrust disk (8), which plays a protective role. Together, they form an auxiliary protection bearing system.

2. The radial-axial active magnetic levitation bearing for motors according to claim 1, characterized in that: The radial magnetic levitation bearing rotor (2), axial displacement sensor detection ring (5), radial displacement sensor detection ring (7) and axial magnetic levitation bearing rotor thrust disk (8) are interference-fitted onto the inner shaft ring (16) along with the auxiliary protection bearing axial positioning adjustment sleeve I (12) and axial positioning adjustment sleeve II (15), forming a radial and axial magnetic levitation bearing inner shaft ring rotor system.

3. The radial-axial active magnetic levitation bearing for motors according to claim 1, characterized in that: The left end cover (1), outer race (4), right end cover (11) and auxiliary protection bearing seat (14) are fixedly connected together with countersunk bolts to form a radial-axial magnetic levitation bearing outer race stator system.

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