A stator permanent magnet counter-rotating dual-rotor high-speed motor and counter-rotating flywheel energy storage system

Abstract

A high-speed motor with a permanent magnet stator and a counter-rotating dual-rotor, counter-rotating flywheel energy storage system, belongs to the technical field of motors for flywheel energy storage systems. This invention aims to address the gyroscopic effect and poor mechanical, thermal, and stability issues experienced by flywheel energy storage systems used in vehicles during high-speed operation. The high-speed motor comprises an outer rotor, an inner rotor, an intermediate stator, and a magnetic isolation cooling bridge. The intermediate stator includes an inner stator and an outer stator, both of which have identical structures. The stator core is axially spaced apart with armature teeth and a double-fault-tolerant tooth structure. The main permanent magnets are embedded in the armature teeth, the boosting permanent magnets are embedded in the double-fault-tolerant teeth, and the armature windings are wound around the armature teeth. Adjacent main permanent magnets and boosting permanent magnets are magnetized tangentially with opposite magnetization directions, and the magnetic fields they generate are superimposed at the air gap. The magnetic isolation cooling bridge is equipped with a continuous "Z"-shaped cooling channel. The counter-rotating flywheel energy storage system comprises a high-speed motor, a main flywheel, an auxiliary flywheel, a magnetic levitation bearing, and a vacuum chamber. It is used in high-speed flywheel motors.

Description

Technical Field

[0001] The present invention relates to a stator permanent magnet type counter-rotating dual-rotor high-speed motor and a counter-rotating flywheel energy storage system, belonging to the technical field of motors for flywheel energy storage systems. Background Art

[0002] The flywheel energy storage system breaks through the limitations of chemical batteries and has the advantages of being pollution-free, having high energy conversion efficiency and power density, and having a long cycle life. It has broad application prospects in the field of electric transportation vehicles and is an important way to help achieve low-carbon and energy transformation goals.

[0003] As the core component of the flywheel energy storage system of a vehicle, the high-speed flywheel motor is the central link in realizing the electromechanical energy conversion of the entire system. Its performance directly affects the quality of the flywheel energy storage system.

[0004] There are the following problems:

[0005] 1. High-speed flywheel motors operate at high speed and high frequency. The high-frequency current and magnetic field changes will cause large core and eddy current losses. In addition, the heat dissipation conditions in the high vacuum operating environment are poor, which causes the motor rotor temperature to rise very easily. Excessive temperature rise will have an adverse effect on the performance of the permanent magnet and even cause thermal demagnetization of the permanent magnet.

[0006] 2. When the flywheel motor rotates at high speed, the centrifugal force of the rotor may exceed the tensile limit of the permanent magnet, increasing the risk of permanent magnet breakage. In severe cases, runaway and bore scraping may occur, causing system damage.

[0007] 3. During vehicle operation, changes in the flywheel shaft's orientation can cause a gyroscopic effect, subjecting the motor to additional unbalanced forces, leading to motor instability and affecting system stability. Under adverse driving conditions, the gyroscopic effect is even more pronounced, causing modal vibration in the system and, in severe cases, motor damage.

[0008] In summary, there are still many problems that need to be solved in the current high-speed flywheel energy storage system, which has become an important constraint on the further development of the flywheel energy storage system for transportation vehicles.

[0009] In view of this, overcoming the above defects in the prior art and providing a high-performance flywheel motor and flywheel energy storage system with low loss and high mechanical strength have become technical problems that need to be solved urgently in this field. Summary of the Invention

[0010] The purpose of the present invention is to solve the problems of gyroscopic effect and poor force, heat and stability in flywheel energy storage systems for vehicles when running at high speeds, and to provide a stator permanent magnet counter-rotating dual-rotor high-speed motor and a counter-rotating flywheel energy storage system.

[0011] The present invention discloses a stator permanent magnet counter-rotating dual-rotor high-speed motor comprising an outer rotor, an inner rotor, an intermediate stator and a magnetic isolation cooling bridge;

[0012] There is an air gap between the outer rotor and the middle stator, and there is an air gap between the inner rotor and the middle stator;

[0013] The intermediate stator includes an inner stator and an outer stator. The inner stator and the outer stator have the same structure, including a stator core, an armature winding, a main permanent magnet and a magnetizing permanent magnet;

[0014] The stator core is provided with armature teeth and double fault-tolerant teeth structure at intervals along the axial direction. The main permanent magnet is embedded in the armature teeth, the magnetization permanent magnet is embedded in the double fault-tolerant teeth, and the armature winding is wound on the armature teeth.

[0015] The adjacent main permanent magnets and the magnetizing permanent magnets are magnetized in a tangential manner with opposite magnetizing directions. The magnetic fields generated by the main permanent magnets and the magnetizing permanent magnets at the air gap are in the same direction, and the magnetic fields generated by the two are superimposed at the air gap.

[0016] A continuous "Z"-shaped cooling channel is provided in the magnetic isolation cooling bridge, and the "Z"-shaped cooling channel is in close contact with the ends of the stator core and the armature winding.

[0017] Preferably, the armature winding adopts a three-phase distributed centralized winding, and the armature winding structure of each phase is the same.

[0018] Preferably, the armature winding distribution of the outer motor is A1-B1-C1-A2-B2-C2, and the armature winding distribution of the inner motor is C1-B1-A1-C2-B2-A2.

[0019] Preferably, coolant flows into the "Z"-shaped cooling channel.

[0020] Preferably, the coolant is used to dissipate heat and cool the stator core, and is also used to dissipate heat and cool the armature winding, main permanent magnet and magnetization permanent magnet transferred to the magnetic isolation cooling bridge through the stator core.

[0021] Preferably, the coolant is non-magnetic and non-conductive cooling oil.

[0022] The counter-rotating flywheel energy storage system of the present invention comprises a stator permanent magnet counter-rotating dual-rotor high-speed motor, a main flywheel, an auxiliary flywheel, a magnetic suspension bearing and a vacuum chamber;

[0023] The outer rotor of the stator permanent magnet counter-rotating dual-rotor high-speed motor is connected to the main flywheel, and the inner rotor is connected to the auxiliary flywheel. Both the main flywheel and the auxiliary flywheel are supported in the vacuum chamber by magnetic bearings, and the magnetic bearings limit the main flywheel and the auxiliary flywheel at the same time.

[0024] Preferably, armature currents of different phase sequences are passed through the armature winding, which can coordinate the speed and direction of the outer rotor and the inner rotor, thereby driving the main flywheel and the auxiliary flywheel to rotate concentrically and counter-rotate, thereby offsetting the gyroscopic torque of the main flywheel and the auxiliary flywheel.

[0025] The stator permanent magnet counter-rotating dual-rotor high-speed motor proposed in the present invention has the following advantages:

[0026] 1. There are neither permanent magnets nor windings on the inner and outer rotors, which not only ensures the mechanical strength but also increases the heat resistance of the motor.

[0027] 2. The stator core is equipped with a double fault-tolerant tooth structure, which can effectively reduce the amplitude of low-order radial force waves, suppress the electromagnetic noise of the motor, and improve the dynamic and steady-state performance of the system.

[0028] 3. Adding a magnetizing permanent magnet between two adjacent main permanent magnets can increase the air gap magnetic flux density of the motor, improve the motor power and torque density. It can also improve the magnetic field waveform of the main permanent magnet, reduce torque ripple, and improve stability.

[0029] The counter-rotating flywheel energy storage system proposed in the present invention has the following advantages:

[0030] 1. There is no physical connection between the main flywheel, auxiliary flywheel and vacuum chamber. They are supported and limited by magnetic bearings, avoiding mechanical contact with the flywheel. They have the characteristics of no mechanical friction, low power consumption, long life, high efficiency, low vibration and noise.

[0031] 2. The dual flywheel structure of the main flywheel and the auxiliary flywheel can effectively suppress the azimuth deviation of the flywheel shaft during high-speed operation. By coordinated control, the present invention proposes that the inner and outer rotors of the motor drive the main flywheel and the auxiliary flywheel to rotate concentrically, offsetting the gyroscopic torque, eliminating the influence of the gyroscopic effect on the system, and improving the stability of the system.

[0032] 3. The dual flywheel structure can effectively utilize space, increasing the flywheel weight that can be used per unit volume, thereby increasing the density of flywheel energy storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic structural diagram of the stator permanent magnet counter-rotating dual-rotor high-speed motor of the present invention;

[0034] Figure 2 1 is a schematic structural diagram of the stator core of the present invention;

[0035] Figure 3 This is a schematic structural diagram of the magnetic isolation cooling bridge of the present invention;

[0036] Figure 4 It is a structural schematic diagram of the "Z" type cooling channel of the present invention;

[0037] Figure 5 3D schematic diagram of the counter-rotating flywheel energy storage system of the present invention;

[0038] Figure 6 It is an axial view of the counter-rotating flywheel energy storage system of the present invention. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0041] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0042] Example 1:

[0043] The following combination Figures 1-4 This embodiment describes a stator permanent magnet type counter-rotating dual-rotor high-speed motor, which includes: an outer rotor 11, an inner rotor 12, an intermediate stator 13 and a magnetic isolation cooling bridge 14;

[0044] There is an air gap between the outer rotor 11 and the intermediate stator 13, and there is an air gap between the inner rotor 12 and the intermediate stator 13;

[0045] The intermediate stator 13 includes an inner stator and an outer stator. The inner stator and the outer stator have the same structure, including a stator core 131, an armature winding 132, a main permanent magnet 133 and a magnetizing permanent magnet 134;

[0046] The stator core 131 is provided with armature teeth and double fault-tolerant teeth structure at intervals along the axial direction. The main permanent magnets 133 are embedded in the armature teeth, the magnetized permanent magnets 134 are embedded in the double fault-tolerant teeth, and the armature windings 132 are wound around the armature teeth.

[0047] The adjacent main permanent magnets 133 and the magnetizing permanent magnets 134 are magnetized in a tangential manner with opposite magnetizing directions. The magnetic fields generated by the main permanent magnets 133 and the magnetizing permanent magnets 134 at the air gap have the same direction, and the magnetic fields generated by the two are superimposed at the air gap.

[0048] A continuous “Z”-shaped cooling channel 141 is provided in the magnetic isolation cooling bridge 14 . The “Z”-shaped cooling channel 141 is in close contact with the ends of the stator core 131 and the armature winding 132 .

[0049] Furthermore, the armature winding 132 adopts a three-phase distributed centralized winding, and the armature winding structure of each phase is the same.

[0050] Furthermore, the armature winding distribution of the outer motor is A1-B1-C1-A2-B2-C2, and the armature winding distribution of the inner motor is C1-B1-A1-C2-B2-A2.

[0051] Furthermore, coolant is introduced into the “Z”-shaped cooling channel 141 .

[0052] Furthermore, the coolant is used to dissipate heat and cool the stator core 131 , and is also used to dissipate heat and cool the armature winding 132 , the main permanent magnet 133 and the magnetizing permanent magnet 134 which are transferred to the magnetic isolation cooling bridge 14 through the stator core 131 .

[0053] Furthermore, the coolant is non-magnetic and non-conductive cooling oil.

[0054] In this embodiment, a continuous "Z"-shaped cooling channel 141 is provided in the magnetic isolation cooling bridge 14, which is filled with a non-magnetic and non-conductive cooling medium. While maintaining the magnetic isolation performance, it can also have a cooling effect, thereby improving the heat dissipation performance of the system.

[0055] In this embodiment, the stator core 131 is made of a new type of low-loss super silicon steel material, which can reduce core loss, suppress motor temperature rise, and improve motor efficiency.

[0056] In this embodiment, the permanent magnets are all made of axially segmented neodymium iron boron material, which reduces the eddy current loss of the permanent magnets and suppresses the temperature rise of the motor.

[0057] In this embodiment, the dual-fault-tolerant tooth structure can effectively adjust the motor magnetic field waveform and reduce the amplitude of the low-order radial force wave, thereby suppressing the electromagnetic noise of the motor and improving the dynamic steady-state performance of the system.

[0058] In this embodiment, the direction of the magnetic field generated by the magnetizing permanent magnet 134 is the same as the direction of the magnetic field generated by the main permanent magnet 133 at the air gap, and the two magnetic fields are superimposed to increase the air gap magnetic field.

[0059] In this embodiment, a magnetic isolation cooling bridge 14 is provided in the stator permanent magnet counter-rotating dual-rotor high-speed flywheel motor, and a continuous Z-shaped cooling channel 141 is provided in the magnetic isolation cooling bridge, and non-magnetic and non-conductive cooling oil is introduced into the interior. By circulating the cooling oil in the Z-shaped cooling channel 141, while maintaining the magnetic isolation performance, the heat directly transferred to the magnetic isolation cooling bridge 14 by the stator core 131 and the heat transferred to the magnetic isolation cooling bridge 14 by the main permanent magnet 133, the auxiliary permanent magnet 134 and the armature winding 132 through the stator core is taken away, thereby achieving the purpose of cooling and effectively solving the technical problem of heat dissipation difficulty in the vacuum environment of the counter-rotating flywheel energy storage system.

[0060] Example 2:

[0061] The following combination Figure 5 and Figure 6 This embodiment describes a counter-rotating flywheel energy storage system, which includes a stator permanent magnet counter-rotating dual-rotor high-speed motor 1, a main flywheel 2, an auxiliary flywheel 3, a magnetic bearing 4 and a vacuum chamber 5;

[0062] The outer rotor 11 of the stator permanent magnet counter-rotating dual-rotor high-speed motor 1 is connected to the main flywheel 2, and the inner rotor 12 is connected to the auxiliary flywheel 3. The main flywheel 2 and the auxiliary flywheel 3 are both supported in the vacuum chamber 5 by magnetic bearings 4, and the magnetic bearings 4 limit the main flywheel 2 and the auxiliary flywheel 3 at the same time.

[0063] Furthermore, by passing armature currents of different phase sequences into the armature winding 132 , the rotational speed and direction of the outer rotor 11 and the inner rotor 12 can be coordinated, thereby driving the main flywheel 2 and the auxiliary flywheel 3 to rotate concentrically and counter-rotate, thereby offsetting the gyroscopic torque of the main flywheel 2 and the auxiliary flywheel 3 .

[0064] In this embodiment, there is no physical connection between the main flywheel 2, auxiliary flywheel 3, and vacuum chamber 5; instead, they are supported and limited by magnetic bearings 4. This avoids mechanical contact with the flywheels, resulting in zero mechanical friction, low power consumption, long life, high efficiency, and low vibration and noise.

[0065] In this embodiment, the armature winding adopts a three-phase distributed centralized winding. The distribution mode of the outer motor is A1-B1-C1-A2-B2-C2, and the distribution mode of the armature winding of the inner motor is C1-B1-A1-C2-B2-A2.

[0066] By introducing armature currents of different phase sequences, the speed and direction of the outer rotor 11 and the inner rotor 12 are coordinated and controlled, driving the main flywheel 2 and the auxiliary flywheel 3 to rotate concentrically, offsetting the gyroscopic torque of the main flywheel 2 and the auxiliary flywheel 3, and eliminating the influence of the gyroscopic effect on the flywheel energy storage system.

[0067] In this embodiment, a dual flywheel structure of a main flywheel and an auxiliary flywheel is provided, which can effectively suppress the azimuth deviation of the flywheel shaft during high-speed operation. By coordinating and controlling the inner and outer rotors of the motor of the present invention to drive the main flywheel and the auxiliary flywheel to rotate concentrically, the gyroscopic torque is offset, the influence of the gyroscopic effect on the system is eliminated, and the stability of the system is improved.

[0068] The dual flywheel structure effectively utilizes space, which increases the flywheel weight that can be used per unit volume, thereby increasing the density of flywheel energy storage.

[0069] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It should be understood that many modifications may be made to the illustrative embodiments, and that other arrangements may be devised, without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in ways other than those described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be employed in conjunction with other described embodiments.

Claims

1. A stator permanent magnet type counter-rotating dual-rotor high-speed motor, characterized in that: It includes: An outer rotor (11), an inner rotor (12), an intermediate stator (13) and a magnetic isolation cooling bridge (14); There is an air gap between the outer rotor (11) and the middle stator (13), and there is an air gap between the inner rotor (12) and the middle stator (13); The intermediate stator (13) includes an inner stator and an outer stator, and the inner stator and the outer stator have the same structure, including a stator core (131), an armature winding (132), a main permanent magnet (133) and a magnetizing permanent magnet (134); An armature tooth and a double fault-tolerant tooth structure are provided on the stator core (131) at intervals along the axial direction, a main permanent magnet (133) is embedded in the armature tooth, a magnetizing permanent magnet (134) is embedded in the double fault-tolerant tooth, and an armature winding (132) is wound on the armature tooth; The adjacent main permanent magnets (133) and the magnetizing permanent magnets (134) are magnetized in a tangential manner with opposite magnetizing directions. The magnetic fields generated by the main permanent magnets (133) and the magnetizing permanent magnets (134) at the air gap have the same direction, and the magnetic fields generated by the two are superimposed at the air gap. A continuous "Z"-shaped cooling channel (141) is provided in the magnetic isolation cooling bridge (14), and the "Z"-shaped cooling channel (141) is in close contact with the ends of the stator core (131) and the armature winding (132).

2. A stator permanent magnet counter-rotating dual-rotor high-speed motor according to claim 1, characterized in that: The armature winding (132) adopts a three-phase distributed centralized winding, and the armature winding structures of each phase are the same.

3. The stator permanent magnet counter-rotating dual-rotor high-speed motor according to claim 2, characterized in that: The armature winding distribution of the outer motor is A1-B1-C1-A2-B2-C2, and the armature winding distribution of the inner motor is C1-B1-A1-C2-B2-A2.

4. The stator permanent magnet counter-rotating dual-rotor high-speed motor according to claim 1, characterized in that: Cooling liquid is introduced into the "Z"-shaped cooling channel (141).

5. The stator permanent magnet counter-rotating dual-rotor high-speed motor according to claim 4, characterized in that: The coolant is used to dissipate heat and cool the stator core (131), and is also used to dissipate heat and cool the heat transferred from the armature winding (132), the main permanent magnet (133) and the magnetizing permanent magnet (134) to the magnetic isolation cooling bridge (14) through the stator core (131).

6. A stator permanent magnet counter-rotating dual-rotor high-speed motor according to claim 4 or 5, characterized in that: The cooling liquid is non-magnetic and non-conductive cooling oil.

7. A counter-rotating flywheel energy storage system, characterized in that: It comprises a stator permanent magnet counter-rotating dual-rotor high-speed motor (1) according to any one of claims 1 to 6, a main flywheel (2), an auxiliary flywheel (3), a magnetic suspension bearing (4) and a vacuum chamber (5); The outer rotor (11) of the stator permanent magnet counter-rotating dual-rotor high-speed motor (1) is connected to a main flywheel (2), and the inner rotor (12) is connected to an auxiliary flywheel (3). Both the main flywheel (2) and the auxiliary flywheel (3) are supported in a vacuum chamber (5) via magnetic suspension bearings (4). The magnetic suspension bearings (4) simultaneously limit the main flywheel (2) and the auxiliary flywheel (3).

8. The counter-rotating flywheel energy storage system according to claim 7, characterized in that: By passing armature currents of different phase sequences into the armature winding (132), the rotational speed and direction of the outer rotor (11) and the inner rotor (12) can be coordinated, thereby driving the main flywheel (2) and the auxiliary flywheel (3) to rotate concentrically and counter-rotate, thereby offsetting the gyroscopic torque of the main flywheel (2) and the auxiliary flywheel (3).

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