Decoupled stator excited superconducting motor

Abstract

The application provides a decoupling type stator excited superconducting motor, which comprises a rear end cover, a front end cover and a casing; at least one superconducting excitation winding is arranged in the casing in an axial direction; two stator structures are arranged on the axial two sides of each superconducting excitation winding, and only one stator structure is arranged between any two adjacent superconducting excitation windings; a rotor structure is arranged on the inner side of each stator structure, and the rotor structure is connected with a rotating shaft which extends from the front end cover; the stator structure comprises a stator core and a stator winding, and the top of the stator tooth on the inner side of the stator core is provided with uniformly distributed magnetic adjustment grooves I; the rotor structure comprises a rotor core and a magnetic conducting block arranged between the two rotor structures, and the outer side of the rotor core is provided with uniformly distributed magnetic adjustment grooves II.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of superconducting motor design, and particularly relates to a decoupling type stator excitation superconducting motor. BACKGROUND

[0002] The power density requirement of motors in the fields of ship propulsion, aerospace, etc. is getting higher and higher, although the development of high-performance magnetic materials has improved the power density of traditional permanent magnet motors, but the power density is still difficult to meet the needs of some special occasions. In recent years, the rapid development of high-temperature superconducting technology has made high-temperature superconducting materials in the fields of motors, flywheel energy storage, magnetic levitation, etc. have been deeply researched, and superconducting motor technology has also been widely concerned. Compared with traditional permanent magnet motors, superconducting motors can improve the utilization efficiency of energy because there is no copper loss; because the resistance of superconducting materials is zero, it can carry more power in unit volume or mass, has the advantages of high power density, etc.

[0003] The traditional superconducting motor structure is similar to the rotor electric excitation motor, the superconducting excitation winding is located in the rotor, and the brush needs to be connected to the power supply, in addition, the dynamic sealing technology and the rotating Dewar are also needed to ensure that the liquid nitrogen used to cool the superconducting material can be correctly injected and kept at low temperature without leakage, the structure of such superconducting motor is relatively complex, and because the superconducting system is located in the rotating body, its working reliability will be affected to a certain extent. In order to solve the above problems, patent 201910731064.1 discloses a double-stator field modulation superconducting motor, which places the superconducting excitation winding and its cooling device on the inner stator to realize the static sealing of the cooling liquid and the brushless of current transmission.

[0004] However, whether it is a traditional superconducting motor or a stator excitation superconducting motor, the excitation magnetic field and the armature magnetic field are coupled during operation, resulting in an induced pulsating voltage at both ends of the excitation winding, which is easy to cause problems such as complex excitation winding current stable control and torque fluctuation.

[0005] In order to solve the above problems, people have been seeking an ideal technical solution. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, and to provide a decoupling type stator excitation superconducting motor, which can realize high power density of superconducting motor and solve the problems of cooling liquid and induced pulsating voltage.

[0007] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows: a decoupling type stator excitation superconducting motor, comprising a rear end cover, a front end cover and a machine shell.

[0008] At least one superconducting field winding is arranged axially in the casing; two stator structures are arranged on the axial sides of each superconducting field winding, and only one stator structure is arranged between any two adjacent superconducting field windings; a rotor structure is arranged inside each stator structure, and the rotor structure is connected with a rotating shaft extending from the front cover;

[0009] The stator structure comprises a stator core and a stator winding, and a magnetic adjustment groove I is arranged on the top of the stator tooth inside the stator core.

[0010] The rotor structure comprises a rotor core and a magnetic conducting block arranged between two rotor structures, and a magnetic adjustment groove II is arranged on the outside of the rotor core.

[0011] Preferably, the magnetic adjustment grooves II of one rotor structure correspond to the magnetic adjustment grooves II between the other rotor structures.

[0012] Preferably, the axial length of the rotor core is the same as the axial length of the stator core, and the number of the magnetic adjustment grooves I is different from the number of the magnetic adjustment grooves II.

[0013] Preferably, the diameter of the magnetic conducting block is smaller than the diameter of the rotor core.

[0014] Preferably, the superconducting field winding is a ring winding, and a heat preservation Dewar is arranged on the inner and outer sides of the superconducting field winding in the radial direction.

[0015] Preferably, the heat preservation Dewar is a double-layer ring structure, and the inside is hollow as a flow channel for cooling liquid.

[0016] Preferably, a cooling / electricity interface is arranged on the casing, and the cooling / electricity interface is connected with the flow channel of the heat preservation Dewar and the superconducting field winding.

[0017] The present application has outstanding substantial features and significant progress compared with the prior art, specifically,

[0018] (1) The excitation magnetic field and the armature magnetic field are decoupled, the end of the superconducting field coil induces a small pulsating voltage, is easy to control, and reduces the torque fluctuation;

[0019] (2) Compared with other superconducting motors which require a set of superconducting coils for one magnetic pole, the present application only needs one set of superconducting coils, and the required superconducting field coil is much smaller than other superconducting motors, and adopts a ring structure, which is simple in structure and easy to install;

[0020] (3) The heat preservation Dewar is fixed in the casing, and does not need to be manually sealed, and the cooling structure is simple, reliable and long in service life. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a sectional view of the present application;

[0022] Figure 2 This is a schematic diagram of the overall external structure of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of the thermal insulation Dewar of the present invention;

[0024] Figure 4 This is a schematic diagram showing the position of the stator structure of the present invention;

[0025] Figure 5 This is a schematic diagram of the stator structure of the present invention;

[0026] Figure 6 This is a schematic diagram of the rotor structure of the present invention;

[0027] Figure 7 This is a schematic diagram of the magnetic circuit of the present invention;

[0028] In the diagram: 1. Rear end cover; 2. Front end cover; 3. Housing; 4. Stator core; 41. Magnetizing slot I; 5. Stator winding; 6. Insulating Dewar; 7. Superconducting excitation winding; 8. Cooling / electrical interface; 9. Rotor core; 91. Magnetizing slot II; 10. Magnetic guide block; 11. Shaft. Detailed Implementation

[0029] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0030] Example 1

[0031] This embodiment provides a decoupled stator-excited superconducting motor, such as Figure 1 As shown, it includes a rear end cover 1, a front end cover 2, and a housing 3. In one embodiment, the housing material is a magnetic material, and the end cover is a non-magnetic material.

[0032] like Figure 2 As shown, the housing 3 has a hole on its side, and the cooling / electrical interface 8 is placed in this hole. The housing 3 is provided with a rotating shaft 11, which extends out of the front end cover 2 and is slidably connected to the rear end cover 1 and the front end cover 2 through bearings.

[0033] At least one superconducting excitation winding 7 is arranged axially inside the housing 3, and there is only one stator structure between any two adjacent superconducting excitation windings. Preferably, this embodiment is described using one superconducting excitation winding as an example.

[0034] The superconducting excitation winding is a ring winding, and thermal insulation Dewar 6 is provided on both the inner and outer sides of the superconducting excitation winding 7 along the radial direction.

[0035] like Figure 3As shown, the insulating Dewar 6 has a double-layered annular structure with a hollow interior serving as a flow channel for the coolant; the superconducting excitation winding 7 is formed by annular winding of superconducting wire, and the entire structure is annular; the coolant of the insulating Dewar 6 and the two ends of the superconducting excitation winding 7 are connected by a cooling / electrical interface 8 to achieve the transfer of coolant and electrical energy. Since the insulating Dewar in this embodiment is fixed inside the casing, manual sealing is not required, resulting in a simple cooling structure, high reliability, and long service life.

[0036] Each superconducting excitation winding 7 has two stator structures arranged on both sides of its axial direction, and there is only one stator structure between any two adjacent superconducting excitation windings 7. For example... Figure 4 As shown, the superconducting excitation winding and stator winding 5 are spatially isolated through a dual-stator structure to reduce the direct coupling between the armature reaction magnetic field and the superconducting coil. It is understood that the insulating dewar 6 is also located between the two stator cores 4.

[0037] The stator structure includes a stator core 4 and a stator winding 5, such as Figure 5 As shown, the stator core 4 is generally annular, with stator teeth inside that fix the stator winding 5. Furthermore, the top of the stator teeth on the inner side of the stator core 4 has uniformly distributed magnetic adjustment slots I41, so that the air gap magnetic field generates harmonics, and the harmonics generate torque; between any two magnetic adjustment slots I41 is a magnetic adjustment tooth I.

[0038] Each stator structure has a rotor structure inside, and the rotor structure is connected to the rotating shaft 11. Specifically, as shown... Figure 6 As shown, the rotor structure includes a rotor core 9 and a magnetic guide block 10 disposed between two rotor structures. The rotor core 9 has uniformly distributed magnetic adjustment slots II91 on its outer side.

[0039] In one embodiment, the diameter of the magnetic block 10 is smaller than the diameter of the rotor core 9.

[0040] In practical implementation, the magnetic adjustment slot II91 of one rotor structure can be matched with the magnetic adjustment teeth between the magnetic adjustment slot II91 of the other rotor structure.

[0041] It should be noted that the number of magnetic adjustment slots II91 in the rotor core 9 is different from the number of magnetic adjustment slots I41 in the stator core 4.

[0042] The working principle of the decoupled stator-excited superconducting motor is as follows:

[0043] like Figure 7 As shown, the magnetic field generated by the superconducting excitation winding 7 after being energized forms a magnetic circuit through the housing 3—stator core 4—air gap—rotor core 9—magnetic block 10—rotor core 9—air gap—stator core 4—housing 3.

[0044] The magnetic field generated by the superconducting field winding 7 is modulated by the modulation slot II 91 of the stator core 4 and the rotor core 9, and then interacts with the magnetic field generated by the stator winding 5 to generate a rotating torque. Since the radial magnetic field generated by the stator winding 5 is completely decoupled from the superconducting field winding 7, the superconducting field winding 7 does not generate an induced pulsating voltage, thereby reducing the control difficulty of the superconducting motor.

[0045] It should be noted that this embodiment describes the basic structure of the present technology, i.e., the stator side and the rotor side are both three-layer structures, which are respectively composed of two stator cores 4 sandwiching a layer of superconducting field winding and two rotor cores 9 sandwiching a magnetic block. The number of superconducting field windings required is small, and the ring structure is simple and easy to install.

[0046] In practice, the output power of the motor can also be improved by adding one layer of superconducting field winding, one layer of stator core 4, one layer of magnetic block 10, and one layer of rotor core 9 in the axial direction to form a five-layer structure.

[0047] It can be understood that the decoupled stator field superconducting motor can also be increased to seven layers, nine layers, etc. in the axial direction to improve the output power of the motor.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit them; although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or some technical features can be replaced by equivalent ones; without departing from the spirit of the technical solutions of the present application, they should be covered in the technical solution range of the present application.

Claims

1. A decoupled stator excited superconducting electric machine, characterized by: The machine shell comprises a rear end cover, a front end cover and a machine shell. At least one superconducting field winding is arranged axially in the machine shell; two stator structures are arranged on each axial side of each superconducting field winding, and only one stator structure is arranged between any two adjacent superconducting field windings; a rotor structure is arranged inside each stator structure, and the rotor structure is connected with a rotating shaft extending out of the front end cover; The stator structure comprises a stator core and a stator winding, and a magnetic adjusting groove I is arranged on the top of the stator tooth inside the stator core; The rotor structure comprises a rotor core and a magnetic conducting block arranged between two rotor structures, and a magnetic adjusting groove II is arranged on the outside of the rotor core; The magnetic adjusting tooth between the magnetic adjusting groove II of one rotor structure corresponds to the magnetic adjusting groove II of another rotor structure.

2. A decoupled stator excited superconducting electric machine according to claim 1, characterized in that: The axial length of the rotor core is the same as the axial length of the stator core, and the number of the magnetic adjusting grooves I and the magnetic adjusting grooves II is different.

3. A decoupled stator excited superconducting electric machine according to claim 2, characterized in that: The diameter of the magnetic conducting block is smaller than the diameter of the rotor core.

4. A decoupled stator excited superconducting electric machine according to claim 1, characterized in that: The superconducting field winding is a ring winding, and a heat preservation Dewar is arranged on the inner and outer sides of the superconducting field winding in the radial direction.

5. A decoupled stator excited superconducting electric machine according to claim 4, characterized in that: The heat preservation Dewar is a double-layer ring structure, and the inside is hollow as a flow channel for cooling liquid.

6. A decoupled stator excited superconducting electric machine according to claim 5, characterized in that: A cooling / electricity interface is arranged on the machine shell, and the cooling / electricity interface is connected with the flow channel of the heat preservation Dewar and the superconducting field winding.

7. A decoupled stator excited superconducting electric machine according to claim 2, characterized in that: The machine shell is made of magnetic conducting material, and the end cover is made of non-magnetic conducting material.

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