Novel conductor plate lap joint structure applied to permanent magnet electric suspension system

Abstract

The invention provides a novel conductor plate lap joint structure applied to a permanent magnet electric suspension system, and relates to the technical field of rail transit, the novel conductor plate lap joint structure comprises a first conductor plate, a second conductor plate and an expansion joint, and the end part of the first conductor plate is provided with a first groove; a second groove is formed in the end, close to the first conductor plate, of the second conductor plate, the second groove and the first groove form a staggered lap joint structure, and a longitudinal gap larger than or equal to 1 mm is formed between the second conductor plate and the first conductor plate; and the expansion joint is arranged between the second conductor plate and the first conductor plate. Compared with a traditional expansion joint track, continuous vortexes can be generated, and more stable suspension force is provided.

Description

Technical Field

[0001] This invention relates to the field of rail transit technology, and more specifically, to a novel conductor plate overlapping structure for use in permanent magnet electric levitation systems. Background Technology

[0002] Magnetic levitation technology is an important development direction for high-speed rail transit. Among them, permanent magnet electric levitation systems have attracted much attention due to their large levitation gap and self-stabilizing characteristics. However, in practical engineering applications, due to the thermal expansion and contraction effect of the conductor plate material, expansion joints must be set. When the permanent magnet array passes through the joint area of ​​the traditional continuous conductor plate, the discontinuity of the conductor plate will disrupt the complete path of the induced eddy current, resulting in violent fluctuations in electromagnetic force. Existing technologies have attempted to improve electrical connectivity by using direct connection or stacked plate methods, but these methods often fail to meet the requirements of thermal deformation adaptability and electromagnetic stability. Either the expansion joint function is lost due to rigid connection, or new electromagnetic interference problems are caused by improper structural design. This inherent contradiction seriously restricts the stability and reliability of the system during long-distance operation.

[0003] Therefore, there is an urgent need for a new conductor plate overlapping structure for use in permanent magnet electric levitation systems to solve the above-mentioned technical problems. Summary of the Invention

[0004] The purpose of this invention is to provide a novel conductor plate overlapping structure for use in permanent magnet electric levitation systems, thereby improving the aforementioned problems. To achieve this objective, the technical solution adopted by this invention is as follows: This application provides a novel conductor plate overlap structure for use in a permanent magnet electric levitation system, comprising: a first conductor plate, a second conductor plate, and an expansion joint. The first conductor plate has a first groove at its end; the second conductor plate has a second groove at its end near the first conductor plate, and the second groove and the first groove form a staggered overlap structure. A longitudinal gap of greater than or equal to 1 mm is provided between the second conductor plate and the first conductor plate; the expansion joint is provided between the second conductor plate and the first conductor plate.

[0005] Preferably, the minimum length of the expansion joint is greater than or equal to the product of the length of a single first conductor plate, the maximum temperature difference, and the coefficient of thermal expansion, wherein the first conductor plate and the second conductor plate have the same structure.

[0006] Preferably, the length of the expansion joint is in the range of 10mm-80mm.

[0007] Preferably, the coupling overlap length of the first conductor plate and the second conductor plate is in the range of 50mm-120mm.

[0008] Preferably, the overlap thickness of the second conductor plate is in the range of 30%-70% of the total thickness of the conductor plate.

[0009] Preferably, the first conductor plate and the second conductor plate are made of copper or aluminum, and the total thickness of the first conductor plate and the second conductor plate is 6mm-12mm.

[0010] Preferably, Halbach array permanent magnets are disposed above both the first conductor plate and the second conductor plate, and the pole spacing of the permanent magnets is 100mm-300mm.

[0011] Preferably, the first conductor plate and the second conductor plate are arranged in a three-dimensional staggered configuration in the overlapping area, wherein the upper top surface of the first groove partially overlaps the lower bottom surface of the second groove, and the projected shape of the overlapping area is rectangular.

[0012] Preferably, the gap width between the top end of the first conductor plate and the top end of the second conductor plate is 1mm-10mm, and the gap is evenly distributed along the length of the conductor plate.

[0013] Preferably, a foundation support layer is provided below the first conductor plate and the second conductor plate, and the first conductor plate and the second conductor plate are fixed to the foundation support layer.

[0014] The beneficial effects of this invention are as follows: This invention creates a staggered overlap structure by setting a groove on the top of the first conductor plate to form a second conductor plate, and setting a longitudinal gap and expansion joint between the two conductor plates. This allows the permanent magnet array to form a continuous eddy current transmission path in the upper and lower conductor plates when passing through the joint area. This retains the thermal deformation adaptation function of the expansion joint and effectively maintains the continuity of the electromagnetic field, thereby significantly improving the electromagnetic stability of the system when passing through the joint. At the same time, the structure avoids the interference of additional components on the suspension gap through reasonable overlap parameter design, simplifies the track laying process and enhances the engineering applicability.

[0015] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing embodiments of the invention. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1This is a front view schematic diagram of the novel conductor plate overlapping structure applied to the permanent magnet electric levitation system as described in this embodiment of the invention; Figure 2 This is a three-dimensional schematic diagram of the novel conductor plate overlapping structure applied to the permanent magnet electric levitation system as described in this embodiment of the invention; Figure 3 This is a schematic diagram comparing the trend of the suspension force attenuation rate of the overlapping structure as a function of the expansion joint length in the embodiments of the present invention. Figure 4 This is a schematic diagram illustrating the variation trend of the suspension force attenuation rate of the overlapping structure as a function of the coupling overlap length and the pole distance in the embodiments of the present invention. Figure 5 This is a schematic diagram illustrating the variation trend of the suspension force attenuation rate of the overlapping structure as a function of the upper plate thickness and speed in an embodiment of the present invention. Figure 6 This is a schematic diagram illustrating the variation trend of the magnetic reluctance abrupt change rate of the overlapping structure as a function of the thickness of the upper plate and the speed, as described in this embodiment of the invention. Figure 7 This is a schematic diagram of the time-varying levitation force generated by the traditional expansion joint and lap joint as described in the embodiments of the present invention; Figure 8 This is a schematic diagram of the auxiliary installation structure described in an embodiment of the present invention.

[0018] The markings in the diagram are: 1. First conductor plate; 2. Second conductor plate; 3. Expansion joint; 4. First groove; 5. Second groove; 6. Positioning pin; 7. Leveling bolt; 8. Anti-vibration pad. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] Example 1: like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, this embodiment provides a novel conductor plate overlapping structure for use in a permanent magnet electric levitation system, including: a first conductor plate 1, a second conductor plate 2, and an expansion joint 3. The first conductor plate 1 has a first groove 4 at its end; the second conductor plate 2 has a second groove 5 at its end near the first conductor plate 1, and the second groove 5 and the first groove 4 form a staggered overlapping structure. A longitudinal gap of greater than or equal to 1 mm is provided between the second conductor plate 2 and the first conductor plate 1; the expansion joint 3 is provided between the second conductor plate 2 and the first conductor plate 1.

[0022] It is understood that the present invention forms a staggered overlapping structure with the second conductor plate 2 by setting a groove on the top of the first conductor plate 1 and setting a longitudinal gap and expansion joint 3 between the two conductor plates, so that when the permanent magnet array passes through the joint area, it can form a continuous eddy current transmission path in the upper and lower conductor plates. This not only retains the thermal deformation adaptation function of the expansion joint 3, but also effectively maintains the continuity of the electromagnetic field, thereby significantly improving the electromagnetic stability of the system when passing through the joint. At the same time, the structure avoids the interference of additional components on the suspension gap through reasonable overlapping parameter design, simplifies the track laying process and enhances the engineering applicability.

[0023] like Figure 7 As shown, this invention incorporates an expansion joint 3 to address structural deformation caused by thermal expansion and contraction and to minimize electromagnetic force abrupt changes caused by eddy current cutoff. From an electromagnetic perspective, the root cause of eddy current cutoff is the breakage of the conductor plate at the expansion joint 3; therefore, the key to the overlap lies in connecting the conductor plates at this point. Traditional welding is a common method for connecting conductor plates, but it eliminates the expansion joint 3 and fails to meet the first condition. Laying a superimposed plate above the expansion joint 3 can also connect the conductors, but if the superimposed plate is too thin, the skin effect at low speeds is significant and cannot effectively suppress eddy current cutoff; if it is too thick, it will directly affect the suspension gap. Furthermore, the superimposed plate needs to be fixed to the conductor plate, which also fails to meet the above two conditions. This invention staggers the joints of adjacent conductor plates and overlaps them (called an overlap joint). This retains the original expansion joint 3, weakens eddy current cutoff, and does not affect the size of the suspension gap. Therefore, it can address structural deformation caused by thermal expansion and contraction and minimize electromagnetic force abrupt changes caused by eddy current cutoff.

[0024] Wherein, the minimum length of the expansion joint 3 is greater than or equal to the product of the length of a single first conductor plate 1, the maximum temperature difference, and the coefficient of thermal expansion, wherein the first conductor plate 1 and the second conductor plate 2 have the same structure.

[0025] It is understood that the determination of the minimum length of the expansion joint 3 in the claims of this invention is based on the principle of thermal expansion compensation. Specifically, this length must ensure that the conductor plate can freely expand and contract without generating compressive stress when the temperature changes. The setting of the expansion joint 3 in the lap joint structure must satisfy the following: its minimum length is not less than the product of the length of a single conductor plate, the maximum temperature difference, and the coefficient of thermal expansion. This relationship is directly derived from the physical calculation of the thermal deformation of the conductor plate to ensure that sufficient deformation space is still maintained between the conductor plates under extreme temperature difference conditions.

[0026] The length of the expansion joint 3 ranges from 10mm to 80mm.

[0027] It is understood that the length of the expansion joint 3 described in the claims of this invention ranges from 10mm to 80mm. This range is determined based on a comprehensive consideration of the thermal deformation requirements of the conductor plate and its impact on electromagnetic performance. The expansion joint 3 in the lap joint structure needs to minimize interference with eddy current continuity while ensuring adaptability to thermal expansion and contraction. When the expansion joint 3 reaches its upper limit of 80mm, the eddy current cutoff effect intensifies, and the levitation force attenuation rate increases significantly. This range ensures that, in typical engineering scenarios (such as a conductor plate length of 25m and a temperature difference of 50℃), the expansion joint 3 can accommodate thermal deformation without excessively disrupting the stability of the electromagnetic field. Figure 3 Type I is a straight-slit conductor plate overlap structure, Type II is a slanted-slit conductor plate overlap structure, and Type III is an overlap-seam conductor plate overlap structure.

[0028] The coupling overlap length of the first conductor plate 1 and the second conductor plate 2 ranges from 50mm to 120mm.

[0029] It is understood that the coupling overlap length of the first conductor plate 1 and the second conductor plate 2 in this invention ranges from 50mm to 120mm. This range is determined based on a comprehensive optimization of eddy current path continuity, structural feasibility, and engineering economy. For example... Figure 4 As shown, the coupling overlap length has a key impact on the distribution pattern of induced eddy currents: if the coupling overlap length is too small (less than 50 mm), the eddy current connection between the upper and lower conductor plates will be insufficient when the permanent magnet passes through the gap, which will aggravate the edge effect and disrupt the smooth transition of the electromagnetic field; while if the coupling overlap length is too large (more than 120 mm), it will not only prolong the time for the magnet to pass through the gap and reduce the system response efficiency, but also increase the processing difficulty and manufacturing cost of the plate. The coupling overlap length refers to the length of overlap between the first conductor plate 1 and the second conductor plate 2 caused by the overlap.

[0030] The overlap thickness of the second conductor plate 2 ranges from 30% to 70% of the total thickness of the conductor plate.

[0031] It is understood that the overlap thickness of the second conductor plate 2 in this invention ranges from 30% to 70% of the total thickness of the conductor plate. This proportion is determined based on a comprehensive optimization analysis of eddy current distribution characteristics, skin effect, and structural stability. Figure 5 and Figure 6 As shown, the upper plate overlap thickness needs to be coordinated with the skin depth at the operating speed to ensure the integrity and continuity of the eddy currents in the overlap area. When the upper plate overlap thickness is too thin (less than 30% of the total thickness), the upper plate may not be able to form a complete eddy current layer due to the large skin depth at low speeds. When the upper plate overlap thickness is too thick (more than 70% of the total thickness), the vertical distance between the lower eddy currents and the permanent magnet will increase at high speeds, weakening the electromagnetic coupling efficiency. The overlap thickness of the second conductor plate 2 represents the height of the second conductor plate 2 at the overlap.

[0032] The first conductor plate 1 and the second conductor plate 2 are made of copper or aluminum, and the total thickness of the first conductor plate 1 and the second conductor plate 2 is 6mm-12mm.

[0033] It is understood that the total thickness of the conductor plate of the present invention is set in the range of 6mm-12mm. This thickness range can ensure that the eddy current has sufficient penetration depth in the conductor plate, while avoiding the processing difficulty caused by excessive thickness or the mechanical strength problem caused by insufficient thickness.

[0034] Halbach array permanent magnets are disposed above both the first conductor plate 1 and the second conductor plate 2, and the pole spacing of the permanent magnets is 100mm-300mm.

[0035] It is understood that the pole pitch range of the permanent magnet in this invention can optimize the matching between the eddy current wavelength and the conductor plate structure, while ensuring the continuity of the magnetic field distribution in the overlap area of ​​the magnet array.

[0036] The first conductor plate 1 and the second conductor plate 2 are arranged in a three-dimensional staggered configuration in the overlapping area, wherein the upper top surface of the first groove 4 partially overlaps the lower bottom surface of the second groove 5, and the projected shape of the overlapping area is rectangular.

[0037] It is understood that the geometric design of this lap joint structure in the present invention, in which the staggered lap is achieved by the nesting of the grooves of the upper and lower conductor plates, ensures the continuity of the eddy current path in three-dimensional space. This shape optimizes the symmetry of the magnetic field distribution and facilitates processing and installation.

[0038] The gap between the top of the first conductor plate 1 and the top of the second conductor plate 2 is 1mm-10mm wide, and the gap is evenly distributed along the length of the conductor plates.

[0039] It is understood that this invention sets the gap width to 1mm-10mm to avoid excessive deviation of the eddy current path due to an excessively large gap. A uniform distribution of the gap along the length of the conductor plate maintains the stability of the magnetic field boundary conditions and reduces interference from longitudinal edge effects.

[0040] A foundation support layer is provided below the first conductor plate 1 and the second conductor plate 2, and the first conductor plate 1 and the second conductor plate 2 are fixed to the foundation support layer.

[0041] In this invention, an insulating coating with a thickness of 0.2-0.5 mm is applied to the surface of the support layer to ensure both electrical isolation and thermal conductivity. The support layer is used to fix the first conductor plate 1 and the second conductor plate 2, and to enable fine-tuning of the height of the support layer to ensure the flatness of the conductor plate installation. Example 2: like Figure 8 As shown, this embodiment adds an auxiliary installation structure based on embodiment 1. The auxiliary installation structure includes positioning pins 6 and leveling bolts 7 set on the foundation support layer. The auxiliary installation structure further includes anti-vibration pads 8, which are made of silicone rubber or polyurethane elastomer, with a thickness of 2-5mm, and are set between the conductor plate and the foundation support layer to buffer the impact of geological vibration.

[0042] The auxiliary installation structure is used to accurately calibrate the flatness and overlap gap of the first conductor plate 1 and the second conductor plate 2 during the laying process. Positioning pins 6 (12mm diameter) are pre-embedded in the foundation support layer, and leveling bolts 7 are connected to the back of the conductor plates. During installation, the overlap gap is calibrated using a laser rangefinder before tightening the bolts to ensure a flatness error ≤0.1mm / m. An additional polyurethane anti-vibration pad 8 (3mm thick) is added between the conductor plate and the foundation support layer to effectively absorb lateral vibrations generated by geological activity, improving the long-term stability of the system under complex geological conditions. This auxiliary structure significantly reduces the risk of electromagnetic interference caused by micro-deformation of the foundation.

[0043] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0044] The above description is merely a specific embodiment 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 technical scope 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 novel conductor plate overlapping structure for use in permanent magnet electric levitation systems, characterized in that, include: The first conductor plate (1) has a first groove (4) at its end. The second conductor plate (2) has a second groove (5) at the end near the first conductor plate (1). The second groove (5) and the first groove (4) form a staggered overlapping structure. A longitudinal gap greater than or equal to 1 mm is provided between the second conductor plate (2) and the first conductor plate (1). Expansion joint (3) is provided between the second conductor plate (2) and the first conductor plate (1).

2. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The minimum length of the expansion joint (3) is greater than or equal to the product of the length of the single first conductor plate (1), the maximum temperature difference, and the coefficient of thermal expansion, wherein the first conductor plate (1) and the second conductor plate (2) have the same structure.

3. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The length of the expansion joint (3) is in the range of 10mm-80mm.

4. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The coupling overlap length of the first conductor plate (1) and the second conductor plate (2) ranges from 50mm to 120mm.

5. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The overlap thickness of the second conductor plate (2) ranges from 30% to 70% of the total thickness of the conductor plate.

6. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The first conductor plate (1) and the second conductor plate (2) are made of copper or aluminum, and the total thickness of the first conductor plate (1) and the second conductor plate (2) is 6mm-12mm.

7. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that... Halbach array permanent magnets are provided above both the first conductor plate (1) and the second conductor plate (2).

8. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The first conductor plate (1) and the second conductor plate (2) form a three-dimensional misaligned configuration in the overlapping area, wherein the upper top surface of the first groove (4) partially overlaps with the lower bottom surface of the second groove (5), and the projected shape of the overlapping area is rectangular.

9. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, The gap width between the top of the first conductor plate (1) and the top of the second conductor plate (2) is 1mm-10mm, and the gap is evenly distributed along the length of the conductor plate.

10. The novel conductor plate overlapping structure for use in a permanent magnet electric levitation system according to claim 1, characterized in that, A foundation support layer is provided below the first conductor plate (1) and the second conductor plate (2), and the first conductor plate (1) and the second conductor plate (2) are fixed to the foundation support layer.

Images