High-temperature superconducting electro-magnetic doubly salient generator

Abstract

The embodiment of the invention discloses a high-temperature superconducting electro-magnetic doubly salient generator, and relates to the field of high-temperature superconducting motors. The stator core and the rotor core are both of a salient pole structure, and the stator teeth are of a parallel tooth structure, so that a larger stator slot space can be generated by the structure, and a superconducting magnet can be conveniently placed; only the armature coil is wound on the stator teeth, and the superconducting magnet is wound across the yoke part of the stator core. The outer edge of the stator yoke wound with the superconducting magnet is provided with a groove, and the superconducting magnet is fixed in the groove; the inner edge of a stator yoke in a large stator groove of the stator core is provided with a salient pole containing superconducting magnet with a proper size, so that magnetic field saturation in the stator yoke can be prevented. By winding the superconducting magnet on the stator yoke part, the influence of the magnetic field generated by the armature coil on the superconducting excitation coil is reduced, the risk of quench of the superconductor is reduced, and the leakage flux in the motor is a parallel magnetic field for the superconductor, so that the alternating current loss of the superconductor can be reduced, and the power density of the motor is further improved.

Description

Technical Field

[0001] This invention relates to the field of high-temperature superconducting motor technology, and in particular to a high-temperature superconducting excitation double salient pole generator. Background Technology

[0002] High-temperature superconducting materials possess advantages such as high current-carrying capacity and low loss, making them promising for applications in the high-power field. As motor technology matures, traditional motor design and optimization methods are increasingly insufficient to improve the ultimate performance of motors. Superconducting motors offer higher electrical or magnetic loads, high power density, and high efficiency, making them promising for applications in high-capacity, high-torque-density propulsion motors and high-power direct-drive wind turbines. However, research on superconducting armature coil technology is still in its early stages, and very few superconducting motors utilize superconducting armature coils. Therefore, currently, adopting a superconducting excitation winding scheme for superconducting motors is more reliable and stable, improving power density while avoiding excessive AC losses.

[0003] Developed from switched reluctance motors, the bis-salient pole motor has garnered widespread attention due to its simple and reliable structure and excellent magnetothermal characteristics. The electrically excited bis-salient pole motor is an evolution of the original permanent magnet bis-salient pole motor. It uses excitation windings on the stator for excitation, allowing for flexible adjustment of the output voltage. It features a simple and reliable structure, good heat dissipation, and suitability for high-speed operation. Applying superconducting magnets to the traditional electrically excited bis-salient pole motor can achieve static sealing of the coolant. However, in this motor, the armature coil generates a large amount of alternating magnetic field, which induces AC losses in the superconducting coil and generates an induced electromotive force in the superconducting winding. The AC losses in the superconducting coil increase the cryogenic cooling power and affect the thermal stability of the superconducting coil, potentially leading to superconductor desuperconductivity.

[0004] Therefore, how to improve the electrically excited doubly salient pole motor so that it can increase power density while reducing the influence of the magnetic field generated by the armature coil on the superconducting excitation winding, and preventing it from losing quench and generating excessive AC losses, has become a research topic. Summary of the Invention

[0005] The embodiments of the present invention provide a high-temperature superconducting excitation doubly salient pole generator, which can reduce the influence of the magnetic field generated by the armature coil on the superconducting magnet while improving the power density of the motor, and prevent the superconducting coil from losing quench and generating excessive AC losses.

[0006] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0007] A high-temperature superconducting excitation doubly salient pole generator includes: a stator core (1), an armature coil (2), a superconducting magnet (3), and a rotor core (4); both the stator core (1) and the rotor core (4) are salient pole structures, and the stator teeth (6) adopt a parallel tooth structure, which can generate a large stator slot space, facilitating the placement of the superconducting magnet (3). The stator core (1) includes: a stator yoke (5) and 12 stator teeth (6), and the superconducting magnet (3) is wound across the yoke of the stator core (1). The rotor core (4) includes a rotor yoke (7) and 8 rotor teeth (8), which are equally spaced along the axial direction of the rotor core (4), and all rotor teeth (8) have the same structure.

[0008] In this design, the armature coil (2) is wound on the stator teeth (6). Furthermore, only the armature coil (2) is wound on the stator teeth. The armature coils (2) on the four teeth that are spatially 90° apart are connected in series.

[0009] Specifically, the gap between adjacent stator teeth (6) serves as a stator slot, forming four large stator slots, with two small stator slots between every two large stator slots. A superconducting magnet (3) is wound across the stator yoke (5) of the large stator slot in the stator core (1). The superconducting magnet (3) being wound across the stator yoke (5) of the large stator slot in the stator core (1) includes: the superconducting magnet (3) is wound on the stator yoke (5), and the wound superconducting magnet (3) is divided into an inner edge part and an outer edge part according to the inner and outer spaces of the stator yoke (5). Among them, a salient pole is provided on the inner edge of the stator yoke (5) in the large stator slot of the stator core (1), and the size of the salient pole matches the thickness of the superconducting magnet (3). The inner edge part of the wound superconducting magnet (3) is fixed on the salient pole, which can prevent the magnetic field inside the stator yoke from saturating. A groove is formed on the outer edge of the stator yoke (5), and the outer edge of the superconducting magnet (3) after winding is fixed in the groove, so that the superconducting magnet is wound on the inner and outer edges of the stator yoke. The thickness of the outer edge of the superconducting magnet (3) after winding is less than the depth of the groove, so that the outer surface of the superconducting magnet (3) is lower than the outer diameter of the stator core (1). The current flowing through two adjacent superconducting magnets (3) is in opposite directions, and the magnetic field polarity generated by the stator teeth (6) that are 90° apart in space is opposite.

[0010] Furthermore, the superconducting magnet (3) has a racetrack-shaped magnet structure. The internal structure of each superconducting magnet (3) includes: a superconducting coil (9), a Dewar (10), and a copper shielding layer (11). The Dewar is a double-layered vacuum container, with a vacuum formed between the inner and outer layers to reduce heat loss. Each superconducting coil (9) is a racetrack-shaped structure composed of multiple turns. The superconducting coil (9) uses high-temperature superconducting tape, such as YBCO (yttrium barium copper oxide) coated conductor. Liquid nitrogen is introduced into the Dewar (10) of each superconducting magnet (3) to provide a cryogenic environment for the superconducting coil (9).

[0011] The high-temperature superconducting excitation doubly salient pole generator provided in this embodiment of the invention has a stator core (1) and a rotor core (4) both with salient pole structures, and the stator teeth adopt a parallel tooth structure. This structure can generate a large stator slot space, which is convenient for the placement of the superconducting magnet (3). Only the armature coil (2) is wound on the stator teeth, and the superconducting magnet (3) is wound across the yoke of the stator core (1). A groove is provided on the outer edge of the stator yoke on which the superconducting magnet (3) is wound, and the superconducting magnet (3) is fixed in the groove. The superconducting magnet (3) is placed on the inner edge of the stator yoke in the large stator slot of the stator core (1) with a salient pole of suitable size, which can prevent the magnetic field saturation in the stator yoke. By winding the superconducting magnet (3) on the stator yoke, the influence of the magnetic field generated by the armature coil (2) on the superconducting excitation coil is reduced, the risk of superconductor failure is reduced, and the leakage magnetic field in the motor is a parallel magnetic field for the superconductor, thereby reducing the AC loss of the superconductor and thus improving the power density of the motor. Furthermore, placing the superconducting magnet (3) on the stator enables static sealing of the superconducting motor's coolant, reducing the complexity of the motor's cooling structure. Thus, while increasing the motor's power density, the influence of the magnetic field generated by the armature coil on the superconducting magnet is reduced, preventing the superconducting coil from quenching and generating excessive AC losses. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a 2D cross-sectional structural diagram of a high-temperature superconducting excitation doubly salient pole generator provided in an embodiment of the present invention;

[0014] Figure 2 A schematic diagram showing the connection between the armature coil and the excitation coil of a high-temperature superconducting excitation doubly salient pole generator provided in an embodiment of the present invention;

[0015] Figure 3 A schematic diagram of the stator slots, stator teeth, and rotor tooth arc lengths of a high-temperature superconducting excitation doubly salient pole generator provided in an embodiment of the present invention;

[0016] Figure 4 Magnetic field distribution diagram of a high-temperature superconducting excitation doubly salient pole generator provided in an embodiment of the present invention;

[0017] Figure 5 A 3D structural schematic diagram of a high-temperature superconducting excitation doubly salient pole generator provided in an embodiment of the present invention;

[0018] Figure 6This is a 2D cross-sectional structural diagram of the superconducting magnet of the high-temperature superconducting excitation doubly salient pole generator provided in an embodiment of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Embodiments of the present invention will be described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in the specification of the present invention means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or couplings. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0020] This invention provides a high-temperature superconducting excitation doubly salient pole generator, with a structure suitable for high-temperature superconducting excitation doubly salient pole generators as follows: Figure 1 , Figure 2 As shown.

[0021] The motor includes: a stator core (1), an armature coil (2), a superconducting magnet (3), and a rotor core (4). The stator core (1) includes a stator yoke (5) and 12 stator teeth (6), wherein the stator teeth (6) adopt a parallel tooth structure; the rotor core (4) includes a rotor yoke (7) and 8 rotor teeth (8), wherein the rotor teeth (8) are arranged at equal intervals along the axial direction of the rotor core (4), and all rotor teeth (8) have the same structure.

[0022] A groove is provided on the outer edge of the stator large slot yoke, and a superconducting magnet (3) is wound across the stator large slot yoke, with the superconducting magnet (3) embedded and fixed in the groove. The groove depth is designed to be greater than the thickness of the superconducting magnet to reduce the complexity of the motor tooling. A salient pole is provided on the inner edge of the stator large slot yoke to prevent the magnetic lines of force in the stator yoke (5) from saturating. By winding the superconducting magnet (3) across the stator yoke (5), the influence of the armature reaction magnetic field on the superconducting coil (2) can be effectively reduced, and the leakage flux of the motor is a parallel magnetic field for the superconductor, which can reduce the AC loss of the superconductor.

[0023] Further as Figure 2 As shown, the armature coil (2) is wound on the stator teeth (6). The armature coils (2) on the four teeth that are spatially 90° apart are connected in series to form a three-phase armature winding; the four sets of excitation coils are connected in series to form an excitation winding, and the currents flowing through the two adjacent superconducting magnets are opposite. The magnetic field generated in the motor is shown in [reference]. Figure 3 .

[0024] In this embodiment, the superconducting magnet (3) includes a multi-turn superconducting coil (9), a Dewar (10), and a copper shielding layer (11). Figure 4 , Figure 5 As shown, the superconducting magnet (3) has a racetrack-shaped magnet structure. The magnet winding of the racetrack-shaped magnet structure is simple and the processing technology is mature. The racetrack-shaped magnet structure has good mechanical and thermal properties, which helps the superconducting coil to operate safely and stably. The racetrack-shaped magnet structure and the motor have a higher degree of matching in structure and performance, and its magnet utilization rate is higher. Each of the superconducting coils (9) is a racetrack-shaped structure, using high-temperature superconducting tape, such as YBCO (yttrium barium copper oxide) coated conductor. The Dewar layer (10) is used for heat insulation and serves as a cooling channel. Liquid nitrogen is introduced into it to provide a cryogenic environment for the superconducting coil (9), so that the superconductor operates at the required ambient temperature, preventing the superconducting magnet from losing supercharging and ensuring the safe and stable operation of the superconducting motor. The copper shielding layer (11) is used to shield the AC magnetic field and reduce AC loss.

[0025] The high-temperature superconducting excitation doubly salient pole generator inherits the high power density advantage of traditional electrically excited doubly salient pole motors. It has a simple and reliable structure. While further improving the power density, it reduces the influence of the magnetic field generated by the armature coil on the superconducting magnet, preventing the superconducting coil from losing quench and generating excessive AC losses.

[0026] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the device embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The above descriptions are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-temperature superconducting excitation doubly salient pole generator, characterized in that, include: Stator core (1), armature coil (2), superconducting magnet (3) and rotor core (4); Both the stator core (1) and the rotor core (4) are salient pole structures, and the stator teeth (6) adopt a parallel tooth structure; The stator core (1) includes: a stator yoke (5) and 12 stator teeth (6), and a superconducting magnet (3) is wound around the yoke of the stator core (1); The rotor core (4) includes a rotor yoke (7) and eight rotor teeth (8). The rotor teeth (8) are arranged at equal intervals along the axial direction of the rotor core (4), and all rotor teeth (8) have the same structure.

2. The high-temperature superconducting excitation doubly salient pole generator according to claim 1, characterized in that, The armature coil (2) is wound on the stator teeth (6); The armature coils (2) on the four teeth that are 90° apart in space are connected in series.

3. The high-temperature superconducting excitation doubly salient pole generator according to claim 1, characterized in that, The gap between adjacent stator teeth (6) serves as a stator slot, forming four large stator slots, with two small stator slots between every two large stator slots; The superconducting magnet (3) is wound across the stator yoke (5) of the large stator slot in the stator core (1).

4. The high-temperature superconducting excitation doubly salient pole generator according to claim 3, characterized in that, The superconducting magnet (3) is wound across the stator yoke (5) of the large stator slot in the stator core (1), comprising: The superconducting magnet (3) is wound on the stator yoke (5), and the wound superconducting magnet (3) is divided into an inner edge part and an outer edge part according to the inner and outer spaces of the stator yoke (5); In the stator core (1), a salient pole is provided on the inner edge of the stator yoke (5) in the large stator slot. The size of the salient pole matches the thickness of the superconducting magnet (3). The inner edge of the superconducting magnet (3) after winding is fixed on the salient pole.

5. The high-temperature superconducting excitation doubly salient pole generator according to claim 4, characterized in that, A groove is opened on the outer edge of the stator yoke (5), and the outer edge of the superconducting magnet (3) after winding is fixed in the groove; The thickness of the outer edge of the superconducting magnet (3) after winding is less than the depth of the groove.

6. The high-temperature superconducting excitation doubly salient pole generator according to claim 4 or 5, characterized in that, The arc length of stator tooth (6) arc_st, the arc length of stator slot arc_slot, and the arc length of rotor tooth (8) arc_rt are equal.

7. The high-temperature superconducting excitation doubly salient pole generator according to claim 1, characterized in that, The currents flowing through two adjacent superconducting magnets (3) are in opposite directions, and the magnetic fields generated by the stator teeth (6) which are 90° apart in space are opposite in polarity.

8. The high-temperature superconducting excitation doubly salient pole generator according to claim 1, characterized in that, The superconducting magnet (3) has a racetrack-shaped magnet structure.

9. The high-temperature superconducting excitation doubly salient pole generator according to claim 8, characterized in that, The internal structure of each superconducting magnet (3) includes: a superconducting coil (9), a Dewar (10), and a copper shielding layer (11); Each superconducting coil (9) is a racetrack-shaped structure composed of multiple turns; The superconducting coil (9) uses high-temperature superconducting tape; Dewar (10) is a double-layered vacuum container in which the inner and outer layers are evacuated to reduce heat loss.

10. The high-temperature superconducting excitation doubly salient pole generator according to claim 9, characterized in that, Liquid nitrogen is introduced into the Dewar (10) of each superconducting magnet (3).

Images