A magnetic suspension permanent magnet speed regulator and speed regulation method thereof

Abstract

The present invention discloses a magnetic suspension permanent magnet speed regulator and a speed regulation method thereof, comprising a cylindrical linear motor, two radial two-degree-of-freedom hybrid magnetic bearings, an axial single-degree-of-freedom hybrid magnetic bearing, two sensor detection rings, and a disc-type permanent magnet regulator. The cylindrical linear motor drives the mover to drive the three magnetic bearing stators to perform axial linear motion according to the load signal change; at the same time, the axial single-degree-of-freedom hybrid magnetic bearing passes current into the coil of the axial single-degree-of-freedom hybrid magnetic bearing according to the detected axial displacement change of the rotor, controls the rotor to return to the center position, and the bearing hybrid magnetic bearing controls the rotor to move with the mover of the cylindrical linear motor, adjusts the air gap size between the conductor disk and the permanent magnet disk, and then changes the output torque. Compared with the prior art, the present invention has higher control accuracy, longer service life, and simpler structure than the traditional permanent magnet speed regulator.

Description

Technical Field

[0001] The invention relates to the field of permanent magnet speed regulators, and in particular to a magnetic suspension permanent magnet speed regulator and a speed regulation method thereof. Background Art

[0002] The current development of permanent magnet speed regulators shows a positive trend, and its application fields are wide. Magnetic suspension permanent magnet speed regulators are widely used in power systems, petrochemicals, ore mining, cement processing and other fields. Compared with the variable frequency speed regulation system driven by a controller, the speed regulation system composed of permanent magnet speed regulators has a wide speed regulation range, 0r / min~0.99n N It has excellent anti-electromagnetic interference performance, can achieve deep speed regulation, and can ensure high transmission efficiency at low speed, saving energy significantly. Therefore, permanent magnet speed regulator can effectively reduce energy loss and can be used in mechanical systems such as fans and pumps in power plants; in the field of petrochemicals, due to its good safety and no sparks or static electricity, it can be used in chemical plants with high dust concentrations.

[0003] Existing permanent magnet speed regulators often use mechanical structures such as gear racks or worms for transmission. The speed regulation mechanism is large and complex, often damaged by friction, and has low speed regulation accuracy, which reduces its service life. Summary of the invention

[0004] Purpose of the invention: In view of the shortcomings of the existing magnetic levitation permanent magnet speed regulator, the present invention provides a magnetic levitation permanent magnet speed regulator and a speed regulation method thereof, adopts a transmission scheme of a cylindrical linear motor and a magnetic levitation bearing, and utilizes the precise control characteristics of the cylindrical linear motor to enable the magnetic levitation permanent magnet speed regulator to achieve precise speed regulation, reduce friction between bearings, and increase motor life.

[0005] Technical solution: The present invention discloses a magnetic suspension permanent magnet speed regulator, comprising a cylindrical linear motor, a cylindrical hybrid magnetic bearing, a conductor disk and a permanent magnet disk; the cylindrical hybrid magnetic bearing is composed of two radial two-degree-of-freedom hybrid magnetic bearings and one axial single-degree-of-freedom hybrid magnetic bearing; the cylindrical hybrid magnetic bearing is located inside the cylindrical linear motor, and the conductor disk and the permanent magnet disk are located on one side of the cylindrical linear motor;

[0006] The cylindrical linear motor includes a cylindrical linear motor stator, which is provided with a cylindrical linear motor mover inside, and a permanent magnet is provided on the cylindrical linear motor stator; a stator slot is opened inside the cylindrical linear motor stator, and a linear motor winding is embedded in the slot; the cylindrical linear motor stator is fixed together with a cylindrical housing, and the cylindrical linear motor mover is fixed on an aluminum alloy plate;

[0007] A radial two-degree-of-freedom hybrid magnetic bearing is placed on each side of the axial single-degree-of-freedom hybrid magnetic bearing, and the stator cores of the two radial two-degree-of-freedom hybrid magnetic bearings and the axial single-degree-of-freedom hybrid magnetic bearing are fixed on the inner side of the aluminum alloy plate; and a plurality of sensor mounting brackets are arranged on the aluminum alloy plate, and radial displacement sensors and axial displacement sensors are installed on the sensor mounting brackets;

[0008] The rotating shaft connects the rotor cores of two radial two-degree-of-freedom hybrid magnetic bearings and an axial single-degree-of-freedom hybrid magnetic bearing and two left and right detection rings, and the radial displacement sensor and the axial displacement sensor are directly opposite to the detection rings; the rotating shaft is connected to the conductor disk, and the conductor disk is directly opposite to the permanent magnetic disk, and permanent magnets are respectively arranged on the outer circumferences of the opposite sides thereof; the permanent magnetic disk extends out of the right end cover from the ball bearing and is connected to the load shaft.

[0009] Furthermore, the axial air gap of the axial single-degree-of-freedom hybrid magnetic bearing is 0.6 mm.

[0010] Further, an air gap between the permanent magnetic disk and the conductor disk is between.

[0011] Further, the speed regulation method is as follows:

[0012] Step (1): In the initial state, three magnetic bearings, namely, an axial single-degree-of-freedom hybrid magnetic bearing and two radial two-degree-of-freedom hybrid magnetic bearings, control the shaft to stably suspend, and the rotor core of the axial single-degree-of-freedom hybrid magnetic bearing is located at the center position of the stator of the axial single-degree-of-freedom hybrid magnetic bearing;

[0013] Step (2): When the cylindrical linear motor detects an external load change, the cylindrical linear motor mover and the three magnetic bearing stators are driven to perform axial movement, the axial movement amount is less than the axial single-degree-of-freedom hybrid magnetic bearing air gap length of 0.6 mm, and the rotor displacement is detected in real time by an axial displacement sensor;

[0014] Step (3): When the cylindrical linear motor moves axially, the two radial two-degree-of-freedom hybrid magnetic bearings are not affected by the axial movement, but the rotor core of the axial single-degree-of-freedom hybrid magnetic bearing will deviate from the center position of the stator of the axial single-degree-of-freedom hybrid magnetic bearing;

[0015] Step (4): When the rotor of the cylindrical linear motor moves axially, the axial displacement sensor detects the axial offset position in real time and calculates the offset; by passing current into the coil of the axial single-degree-of-freedom hybrid magnetic bearing, the current is controlled to change the air gap magnetic density of the axial single-degree-of-freedom hybrid magnetic bearing, thereby generating an axial suspension force, so that the rotor core of the axial single-degree-of-freedom hybrid magnetic bearing returns to the center position of the stator of the axial single-degree-of-freedom hybrid magnetic bearing;

[0016] Step (5): The rotor core of the axial single-degree-of-freedom hybrid magnetic bearing drives the conductor disk away from or close to the permanent magnetic disk, thereby changing the final output torque.

[0017] Furthermore, when the cylindrical linear motor detects a change in external load, the rotor of the cylindrical linear motor moves axially, the conductor disk moves left and right, and the air gap between the conductor disk and the permanent magnet disk changes. When the air gap is larger, the air gap magnetic density is smaller, and the output torque is smaller; when the air gap is smaller, the air gap magnetic density is larger, and the output torque is larger; the target motor shaft is connected to the load shaft, and when the load shaft outputs high torque, the motor runs at high speed; when the load shaft outputs low torque, the motor runs at low speed.

[0018] Furthermore, when adjusting the speed, the calculation method of the driving force required by the axial single-degree-of-freedom hybrid magnetic bearing is:

[0019] When the rotating shaft drives the rotor core and the conductor disk of the axial single-degree-of-freedom hybrid magnetic bearing to move axially, the maximum axial driving force F H =F M -F 盘 , where F M is the driving force of the cylindrical linear motor, F 盘 is the axial interaction force between the conductor disk and the two permanent magnets on the permanent magnetic disk;

[0020] The attraction between the conductor disk and the permanent magnets on the permanent disk is calculated using the magnetic dipole model. Each permanent magnet is regarded as a magnetic dipole, and the magnetic dipole moment of the magnetic dipole is equal to the product of the magnetic field intensity generated by the permanent magnet and the area of ​​the permanent magnet.

[0021] Assume the magnetic dipole moment of the conductor disk permanent magnet is The magnetic dipole moment of the permanent magnet on the permanent magnetic disk is The force received It is expressed as:

[0022]

[0023] Where Γ is the gradient operator, The magnetic dipole moment The magnetic field generated;

[0024] For the axial interaction force F between two permanent magnets 盘 for:

[0025]

[0026] Where μ0 is the vacuum magnetic permeability, which is about 4π×10 -7 T·m / A, r is the distance between two magnetic dipole moments.

[0027] Furthermore, the magnetic suspension permanent magnet speed regulator is also used in conjunction with a power-generating motor to achieve torque transmission.

[0028] Beneficial effects:

[0029] The present invention introduces a cylindrical linear motor on the basis of the existing magnetic levitation permanent magnet speed regulator. In terms of performance, the cylindrical linear motor has the advantages of high control accuracy and fast response speed. The transmission mechanism adopts magnetic levitation technology, has no friction and wear, has a simple structure, no friction and wear, and a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural block diagram of the magnetic levitation permanent magnet speed regulator in the embodiment of the present application.

[0031] Among them, 1-magnetic levitation permanent magnet speed regulator, 2-cylindrical linear motor, 3-radial two-degree-of-freedom hybrid magnetic bearing, 4-cylindrical hybrid magnetic bearing, 5-axial single-degree-of-freedom hybrid magnetic bearing, 6-radial displacement sensor, 7-disc permanent magnet regulator, 8-axial displacement sensor, 9-cylindrical linear motor stator, 10-cylindrical linear motor mover, 11-aluminum alloy plate, 12-sensor mounting bracket, 13-first detection ring, 14-radial two-degree-of-freedom hybrid magnetic bearing radial stator, 15-radial two-degree-of-freedom hybrid magnetic bearing radial rotor core, 16-axial single-degree-of-freedom hybrid magnetic bearing stator, 17-axial single-degree-of-freedom hybrid magnetic bearing rotor core, 18-second detection ring, 19-conductor disk, 20-permanent magnetic disk, 21-load shaft, 22-ball bearing, 23-rotating shaft, 24-first permanent magnet, 25-second permanent magnet, 26-upper end cover. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings.

[0033] The present invention discloses a magnetic suspension permanent magnet speed regulator and a speed regulation method, see Figure 1 The magnetic suspension permanent magnet speed regulator 1 includes: a cylindrical linear motor 2, a cylindrical hybrid magnetic bearing 4 composed of two radial two-degree-of-freedom hybrid magnetic bearings 3, an axial single-degree-of-freedom hybrid magnetic bearing 5, and a disc-type permanent magnet regulator 7.

[0034] The disc-type permanent magnetic regulator 7 includes a disc-shaped conductor disc 19 and a permanent magnetic disc 20 which are arranged opposite to each other. The cylindrical hybrid magnetic bearing 4 is located inside the cylindrical linear motor 2, and the conductor disc 19 and the permanent magnetic disc 20 are located on the right side of the cylindrical linear motor 2.

[0035] The cylindrical linear motor 2 comprises a cylindrical linear motor stator 9 and an upper end cover 26 , inside of which a cylindrical linear motor mover 10 is arranged. The cylindrical linear motor mover 10 is fixed on an aluminum alloy plate 11 .

[0036] A radial two-degree-of-freedom hybrid magnetic bearing 3 is placed on each side of the axial single-degree-of-freedom hybrid magnetic bearing 5, and the three hybrid magnetic bearings jointly support the rotor suspension. The upper and lower ends of the two radial two-degree-of-freedom hybrid magnetic bearings 3 and the axial single-degree-of-freedom hybrid magnetic bearing 5 are fixed on the aluminum alloy plate 11 together with the mover 10 of the cylindrical linear motor, and corresponding multiple radial displacement sensors 6 and axial displacement sensors 8 are arranged on both sides thereof.

[0037] The rotating shaft 23 connects the rotor cores of the two radial two-degree-of-freedom hybrid magnetic bearings 3 and the axial single-degree-of-freedom hybrid magnetic bearing 5 with the left and right detection rings, namely the first detection ring 13 and the second detection ring 18. The radial displacement sensor 6 and the axial displacement sensor 8 are directly opposite to the first detection ring 13 and the second detection ring 18; see Figure 1 The radial displacement sensor 6 and the axial displacement sensor 8 are fixed by the sensor mounting bracket 12. The axial displacement sensor 8 is arranged perpendicular to the ring surface of the second detection ring 18, and the radial displacement sensor 6 is arranged opposite to the first detection ring 13 and the second detection ring 18.

[0038] The rotating shaft 23 is connected to the conductor disk 19, and the conductor disk 19 is directly opposite to the permanent magnetic disk 20, and permanent magnets are respectively arranged on the outer circumference of the opposite side. The first permanent magnet 24 is arranged on the conductor disk 19, and the second permanent magnet 25 is arranged on the permanent magnetic disk 20. The permanent magnetic disk 20 extends out of the right end cover through the ball bearing 22 and is connected to the load shaft 21.

[0039] The radial stator 14 of the radial two-degree-of-freedom hybrid magnetic bearing and the radial rotor core 15 of the radial two-degree-of-freedom hybrid magnetic bearing are opposite to the rotating shaft 23 , and the stator 16 of the axial single-degree-of-freedom hybrid magnetic bearing and the rotor core 17 of the axial single-degree-of-freedom hybrid magnetic bearing are opposite to the rotating shaft 23 .

[0040] The axial air gap of the axial single-degree-of-freedom hybrid magnetic bearing 5 is 0.6 mm, and the air gap between the permanent magnetic disk 20 and the conductor disk 19 is between (0 mm, 5 mm), and is set to 1 mm in this embodiment.

[0041] The working process of the magnetic suspension permanent magnet speed regulator in this embodiment is as follows:

[0042] Step (1): In the initial state, three magnetic bearings, namely the axial single-degree-of-freedom hybrid magnetic bearing 5 and the two radial two-degree-of-freedom hybrid magnetic bearings 3, control the rotating shaft 23 to be stably suspended, and the rotor core 17 of the axial single-degree-of-freedom hybrid magnetic bearing is at the center position of the stator 16 of the axial single-degree-of-freedom hybrid magnetic bearing.

[0043] Step (2): When the cylindrical linear motor 2 detects changes in external loads such as flow rate and pressure, it drives the cylindrical linear motor mover 10 and the three magnetic bearing stators to perform axial movement. The axial movement amount is less than the axial single-degree-of-freedom hybrid magnetic bearing 5 air gap length of 0.6 mm, and the rotor displacement is detected in real time through the axial displacement sensor.

[0044] Step (3): To ensure that the axial single-degree-of-freedom hybrid magnetic bearing 5 can work normally, when the cylindrical linear motor rotor 10 moves axially, the axial displacement sensor 8 detects the axial offset position in real time and calculates the offset; by passing current into the coil of the axial single-degree-of-freedom hybrid magnetic bearing 5, the current is controlled to change the air gap magnetic density of the axial single-degree-of-freedom hybrid magnetic bearing 5, thereby generating an axial suspension force, so that the rotor core 17 of the axial single-degree-of-freedom hybrid magnetic bearing returns to the center position of the stator 16 of the axial single-degree-of-freedom hybrid magnetic bearing.

[0045] Step (4): The rotor core 17 of the axial single-degree-of-freedom hybrid magnetic bearing drives the conductor disk 19 to move away from or closer to the permanent magnetic disk 20, thereby changing the final output torque.

[0046] When the cylindrical linear motor 2 detects a change in external load, the cylindrical linear motor mover 10 moves axially, the conductor disk 19 moves left and right, and the air gap between the cylindrical linear motor and the permanent magnetic disk 20 changes. When the air gap is larger, the air gap magnetic density is smaller, and the output torque is smaller. When the air gap is smaller, the air gap magnetic density is larger, and the output torque is larger. The target motor shaft is connected to the load shaft. When the load shaft outputs high torque, the motor runs at high speed. When the load shaft outputs low torque, the motor runs at low speed.

[0047] The disc-type permanent magnet speed regulator of the present invention is jointly adjusted with the axial single-degree-of-freedom hybrid magnetic bearing 5, and the calculation method of the driving force required by the axial single-degree-of-freedom hybrid magnetic bearing 5 is:

[0048] (1) When the rotating shaft 23 drives the rotor core 17 and the conductor disk 19 of the axial single-degree-of-freedom hybrid magnetic bearing to move axially, the maximum axial thrust F H =F M -F 盘 , where F M is the driving force of the cylindrical linear motor 2, F 盘 is the axial interaction force between the two permanent magnets on the conductor disk 19 and the permanent magnetic disk 20.

[0049] (2) Since the first and second permanent magnets 24 and 25 of the conductor disk 19 and the permanent magnetic disk 20 are not point permanent magnets, the attraction between the two permanent magnets can be approximately calculated by the magnetic dipole model. In this model, each permanent magnet is regarded as a magnetic dipole, and its magnetic dipole moment is a vector pointing from the south pole to the north pole, and its magnitude is equal to the product of the strength and area of ​​the magnetic field generated by the magnet.

[0050] (3) For a magnetic dipole moment The first permanent magnet 24 has a magnetic dipole moment of In the magnetic field generated by the second permanent magnet 25, the force It can be expressed as:

[0051]

[0052] Where Γ is the gradient operator, The magnetic dipole moment The magnetic field generated.

[0053] (4) For the axial interaction force F between the two permanent magnets 盘 for:

[0054]

[0055] Where μ0 is the vacuum magnetic permeability, which is about 4π×10 -7 T·m / A, r is the distance between two magnetic dipole moments.

[0056] The magnetic suspension permanent magnet speed regulator designed by the present invention is also used in conjunction with a motor that generates power to achieve torque transmission.

[0057] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A magnetic suspension permanent magnet speed regulator, characterized in that: It comprises a cylindrical linear motor (2), a cylindrical hybrid magnetic bearing (4), a conductor disk (19) and a permanent magnetic disk (20); the cylindrical hybrid magnetic bearing (4) is composed of two radial two-degree-of-freedom hybrid magnetic bearings (3) and an axial single-degree-of-freedom hybrid magnetic bearing (5); the cylindrical hybrid magnetic bearing (4) is located inside the cylindrical linear motor (2), and the conductor disk (19) and the permanent magnetic disk (20) are located on one side of the cylindrical linear motor; The cylindrical linear motor (2) comprises a cylindrical linear motor stator (9), in which a cylindrical linear motor mover (10) is arranged, on which a permanent magnet is arranged; a stator slot is opened in the cylindrical linear motor stator (9), in which a linear motor winding is embedded; the cylindrical linear motor stator (9) is fixed to a cylindrical housing (1), and the cylindrical linear motor mover (10) is fixed to an aluminum alloy plate (11); A radial two-degree-of-freedom hybrid magnetic bearing (3) is placed on the left and right of the axial single-degree-of-freedom hybrid magnetic bearing (5), and the stator cores of the two radial two-degree-of-freedom hybrid magnetic bearings (3) and the axial single-degree-of-freedom hybrid magnetic bearing (5) are fixed on the inner side of the aluminum alloy plate (11); and a plurality of sensor mounting brackets are arranged on the aluminum alloy plate (11), and radial displacement sensors and axial displacement sensors are mounted on the sensor mounting brackets; The rotating shaft (23) connects the rotor cores of two radial two-degree-of-freedom hybrid magnetic bearings (3) and an axial single-degree-of-freedom hybrid magnetic bearing (5) and two left and right detection rings, and the radial displacement sensor and the axial displacement sensor are directly opposite to the detection rings; the rotating shaft (23) is connected to the conductor disk (19), and the conductor disk (19) is directly opposite to the permanent magnetic disk (20), and permanent magnets are respectively arranged on the outer circumferences of the opposite sides; the permanent magnetic disk (20) extends out of the right end cover from the ball bearing and is connected to the load shaft (21).

2. The magnetic suspension permanent magnet speed regulator according to claim 1 is characterized in that: The axial air gap of the axial single-degree-of-freedom hybrid magnetic bearing (5) is 0.6 mm.

3. The magnetic suspension permanent magnet speed regulator according to claim 1 is characterized in that: The air gap between the permanent magnetic disk (20) and the conductor disk (19) is between (0 mm, 5 mm).

4. The magnetic suspension permanent magnet speed regulator according to any one of claims 1 to 3, characterized in that: The speed adjustment method is as follows: Step (1): In the initial state, three magnetic bearings, namely, an axial single-degree-of-freedom hybrid magnetic bearing (5) and two radial two-degree-of-freedom hybrid magnetic bearings (3), control the rotating shaft (23) to be stably suspended, and the rotor core (17) of the axial single-degree-of-freedom hybrid magnetic bearing (5) is located at the center position of the stator (16) of the axial single-degree-of-freedom hybrid magnetic bearing (5); Step (2): When the cylindrical linear motor (2) detects a change in external load, the cylindrical linear motor mover (10) and the three magnetic bearing stators are driven to perform axial movement, the axial movement amount is less than 0.6 mm of the air gap length of the axial single-degree-of-freedom hybrid magnetic bearing (5), and the rotor displacement amount is detected in real time by an axial displacement sensor; Step (3): when the cylindrical linear motor (2) moves axially, the two radial two-degree-of-freedom hybrid magnetic bearings (3) are not affected by the axial movement, but the rotor core (17) of the axial single-degree-of-freedom hybrid magnetic bearing (5) will deviate from the center position of the stator (16) of the axial single-degree-of-freedom hybrid magnetic bearing (5); Step (4): when the cylindrical linear motor rotor (10) moves axially, the axial displacement sensor detects the axial offset position in real time and calculates the offset; by passing current into the coil of the axial single-degree-of-freedom hybrid magnetic bearing (5), the current is controlled to change the air gap magnetic density of the axial single-degree-of-freedom hybrid magnetic bearing (5), thereby generating an axial suspension force, so that the rotor core (17) of the axial single-degree-of-freedom hybrid magnetic bearing (5) returns to the center position of the stator (16) of the axial single-degree-of-freedom hybrid magnetic bearing (5); Step (5): The rotor core (17) of the axial single-degree-of-freedom hybrid magnetic bearing (5) drives the conductor disk (19) away from or close to the permanent magnetic disk (20), thereby changing the final output torque.

5. The magnetic suspension permanent magnet speed regulator according to claim 4 is characterized in that: When the cylindrical linear motor (2) detects a change in external load, the rotor (10) of the cylindrical linear motor moves axially, the conductor disk (19) moves left and right, and the air gap between the conductor disk (19) and the permanent magnet disk (20) changes. When the air gap is larger, the air gap magnetic density is smaller, and the output torque is smaller; when the air gap is smaller, the air gap magnetic density is larger, and the output torque is larger; the target motor shaft is connected to the load shaft, and when the load shaft outputs high torque, the motor runs at high speed; when the load shaft outputs low torque, the motor runs at low speed.

6. The magnetic suspension permanent magnet speed regulator according to claim 4 is characterized in that: When adjusting the speed, the calculation method of the driving force required by the axial single-degree-of-freedom hybrid magnetic bearing (5) is: (1) When the rotating shaft (23) drives the rotor core (17) and the conductor disk (19) of the axial single-degree-of-freedom hybrid magnetic bearing (5) to move axially, the maximum axial thrust F exerted on the axial single-degree-of-freedom hybrid magnetic bearing (5) is H =F M -F 盘 , where F M is the driving force of the cylindrical linear motor (2), F 盘 is the axial interaction force between the two permanent magnets on the conductor disk (19) and the permanent magnetic disk (20); (2) The attraction between the conductor disk (19) and the permanent magnets on the permanent magnetic disk (20) is calculated using a magnetic dipole model, where each permanent magnet is regarded as a magnetic dipole, and the magnetic dipole moment of the magnetic dipole is equal to the product of the magnetic field intensity generated by the permanent magnet and the area of ​​the permanent magnet; (3) Assume that the magnetic dipole moment of the permanent magnet of the conductor disk (19) is The magnetic dipole moment of the permanent magnet on the permanent magnetic disk (20) is The force received It is expressed as: Among them, Γ is the gradient operator, The magnetic dipole moment The magnetic field generated; (4) For the axial interaction force F between the two permanent magnets 盘 for: Where μ0 is the vacuum magnetic permeability, which is about 4π×10 -7 T·m / A, r is the distance between two magnetic dipole moments.

7. The magnetic suspension permanent magnet speed regulator according to any one of claims 1-3, 5-6, characterized in that: The magnetic suspension permanent magnet speed regulator is also used in conjunction with a motor that generates power to achieve torque transmission.

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