Hybrid excitation linear eddy current braking system

Abstract

The invention provides a hybrid excitation linear eddy current braking system. The hybrid excitation linear eddy current braking system comprises an electromagnetic braking assembly, a permanent magnet braking assembly and a coil winding assembly. The electromagnetic braking assembly and the permanent magnet braking assembly are both installed at the bottom of a train so as to induce eddy current with a rail and brake the train. The coil winding assembly is arranged in the length direction of the track and forms a secondary part of the linear motor, and the permanent magnet brake assembly forms a primary part of the linear motor. And the train is braked. Eddy braking force is generated through common excitation of the electromagnetic braking assembly and the permanent magnet braking assembly, and the total power consumption and weight of the train brake can be greatly reduced. Meanwhile, the coil winding assembly with the three-phase sine alternating current and the permanent magnet braking assembly below the bottom of the train form a secondary part and a primary part of the linear motor, electromagnetic force is generated by giving appropriate current, the horizontal component of the electromagnetic force also plays a braking role, and therefore the braking performance of the train can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of eddy current braking, and in particular to a composite excitation linear eddy current braking system. Background Art

[0002] The eddy current braking system is an electromagnetic device based on the electromagnetic induction theorem. The primary part is equivalent to the main magnetic field source, and the secondary contains conductive materials. The relative movement of the primary magnetic field and the secondary magnetic field induces eddy currents in the secondary conductor, which interact with the synthetic magnetic field to generate braking force. From the perspective of energy conversion, the mechanical energy of the eddy current braking system mover is first converted into electrical energy in the secondary conductor, and then the electrical energy in the secondary conductor is converted into heat energy and released into the air. The high-speed rail does not contact the rails, which is a non-adhesion braking.

[0003] However, the existing eddy current braking system has the problems of poor braking performance, uncontrollable braking force and only braking without driving. Summary of the invention

[0004] In view of the above problems existing in the prior art, the technical problem to be solved by the present invention is that the existing eddy current braking system has the problem of poor braking performance.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: a composite excitation linear eddy current braking system, comprising: an electromagnetic braking assembly, a permanent magnet braking assembly and a coil winding assembly;

[0006] The electromagnetic brake assembly and the permanent magnet brake assembly are both installed at the bottom of the train to induce eddy currents with the track and brake the train;

[0007] The coil winding assembly is arranged along the length direction of the track, and the coil winding assembly constitutes the secondary part of the linear motor, and the permanent magnet brake assembly constitutes the primary part of the linear motor; so as to brake the train.

[0008] Preferably, the magnitude of the direct current passed into the electromagnetic brake assembly is adjustable.

[0009] Preferably, the phase sequence of the three-phase alternating current passed into the coil winding assembly can be changed.

[0010] Preferably, the electromagnetic brake assembly includes: an iron core and a DC excitation coil; the iron core includes a connecting portion and a winding portion, a plurality of the winding portions are arranged at intervals along the length direction of the track, and the bottom end of the winding portion is installed on the connecting portion, the other end of the winding portion faces the track, and an air gap is provided between the winding portion and the track; a DC excitation coil is wound around each of the winding portions.

[0011] Preferably, the permanent magnet brake assembly comprises a plurality of permanent magnets, the plurality of permanent magnets correspond to the winding parts one by one, and the permanent magnets are mounted at one end of the winding part close to the track.

[0012] Preferably, the permanent magnets are arranged in a rectangular shape, and a plurality of the permanent magnets adopt a Halbach array.

[0013] Preferably, a yoke is installed on a side of the connecting portion away from the winding portion.

[0014] Preferably, the yoke is formed by stacking silicon steel sheets.

[0015] Preferably, a plurality of salient pole slots are provided in the length direction of the track, and the coil winding assembly is embedded in the plurality of salient pole slots.

[0016] Preferably, the coil winding assembly adopts fractional slot concentrated full-tooth winding embedded in the salient pole slot located on the track.

[0017] Compared with the prior art, the present invention has at least the following advantages:

[0018] 1. In the present invention, when the train needs to brake when entering the station, after the electromagnetic brake assembly is fed with direct current, the electromagnetic brake assembly and the permanent magnet brake assembly induce eddy currents on the track, thereby generating non-adhesive eddy current braking force, and the horizontal component of the force plays a braking role. The eddy current braking force is generated by the electromagnetic brake assembly and the permanent magnet brake assembly being jointly excited, which can greatly reduce the total power consumption and weight of the train brake. At the same time, the coil winding assembly that passes the three-phase sinusoidal alternating current and the permanent magnet brake assembly under the bottom of the train constitute the secondary part and the primary part of the linear motor, and the electromagnetic force is generated by giving a suitable current, and the horizontal component of the force also plays a braking role, so that the braking performance of the train can be improved.

[0019] 2. In the present invention, the magnitude of the eddy current braking force can be changed by adjusting the magnitude of the direct current passed into the electromagnetic brake assembly, thereby enhancing the reliability of the braking system and making the braking of the train more stable.

[0020] 3. In the present invention, the braking and driving of the train can be achieved by changing the phase sequence of the three-phase alternating current passed into the coil winding assembly; for this purpose, when the train leaves the station, the phase sequence of the alternating current of the coil winding assembly is changed, so that a driving force for the train can be generated.

[0021] 4. In the present invention, a Halbach array formed by superimposing a radial permanent magnet array and an orthogonal permanent magnet array is used to replace a conventional permanent magnet array, and permanent magnets with different magnetization directions are arranged in a certain order, so that the magnetic field of the array is enhanced on one side and weakened on the other side, and most of the magnetic flux is concentrated at the bottom of the permanent magnet, and the braking capacity of the eddy current braking system is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation of the present invention, the following will briefly introduce the drawings required for use in the specific implementation. In all the drawings, each element or part is not necessarily drawn according to the actual scale.

[0023] Figure 1 This is a schematic structural diagram of the composite excitation linear eddy current braking system provided by the present invention.

[0024] Figure 2 This is a magnetic field line distribution diagram of the permanent magnet Halbach array structure provided by the present invention.

[0025] Figure 3 This is a schematic diagram of the secondary part fractional slot concentrated winding arrangement provided by the present invention.

[0026] Figure 4 This is a schematic structural diagram of the coil winding assembly provided by the present invention.

[0027] Figure 5 This is a magnetic induction intensity diagram of the composite excitation linear eddy current braking system provided by the present invention.

[0028] Figure numerals: 1- iron core, 11- connecting part, 12- winding part, 2- DC excitation coil, 3- permanent magnet, 4- yoke, 5- coil winding assembly, 6- track, 61- salient pole slot. DETAILED DESCRIPTION

[0029] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0030] In the present invention, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] See also Figure 1-Figure 5 , the embodiment provided by the present invention: a composite excitation linear eddy current braking system, comprising: an electromagnetic braking component, a permanent magnet braking component and a coil winding component 5; the electromagnetic braking component and the permanent magnet braking component are both installed at the bottom of the train to induce eddy current with the track 6 and brake the train; the coil winding component 5 is arranged along the length direction of the track 6, and the coil winding component 5 constitutes the secondary part of the linear motor, and the permanent magnet braking component constitutes the primary part of the linear motor; to brake the train. When the train needs to brake when entering the station, after the electromagnetic braking component is connected to the direct current, the electromagnetic braking component and the permanent magnet braking component induce eddy current on the track 6, thereby generating a non-adhesive eddy current braking force, and the horizontal component of the force plays a braking role. The eddy current braking force is generated by the electromagnetic braking component and the permanent magnet braking component, which can greatly reduce the total power consumption and weight of the train brake. At the same time, the coil winding component 5 connected to the three-phase sinusoidal alternating current and the permanent magnet braking component under the bottom of the train constitute the secondary part and the primary part of the linear motor, and the electromagnetic force is generated by giving a suitable current, and the horizontal component of the force also plays a braking role, so that the braking performance of the train can be improved. Furthermore, the magnitude of the DC current passed into the electromagnetic brake assembly is adjustable; by adjusting the magnitude of the DC current passed into the electromagnetic brake assembly, the magnitude of the eddy current braking force can be changed, thereby enhancing the reliability of the braking system and making the braking of the train more stable; further, the phase sequence of the three-phase AC current passed into the coil winding assembly 5 is changeable; by changing the phase sequence of the three-phase AC current passed into the coil winding assembly 5, the braking and driving of the train can be achieved; for this reason, when the train leaves the station, the phase sequence of the AC current of the coil winding assembly 5 is changed, thereby generating a driving force for the train.

[0033] See also Figure 1-Figure 5In other embodiments, the electromagnetic brake assembly includes: an iron core 1 and a DC excitation coil 2; the iron core 1 includes a connecting portion 11 and a winding portion 12, a plurality of winding portions 12 are arranged at intervals along the length direction of the track 6, and the bottom end of the winding portion 12 is installed on the connecting portion 11, the other end of the winding portion 12 faces the track 6, and an air gap is provided between the winding portion 12 and the track 6; a DC excitation coil 2 is wound on each winding portion 12. In specific implementation, the gap between two adjacent winding portions 12 is a straight slot, and the DC excitation coil 2 is arranged in the straight slot; a DC current is passed toward the plurality of DC excitation coils 2, so that a magnetic field can be generated, and an electromotive force eddy current is generated in the track 6, so as to achieve braking of the train. Furthermore, a yoke 4 is installed on the side of the connecting portion 11 away from the winding portion 12; the leakage magnetic flux of the electromagnetic brake assembly is restrained from diffusing outward by the yoke 4; the yoke 4 is formed by stacking silicon steel sheets.

[0034] See also Figure 1-Figure 5 In other embodiments, the permanent magnet brake assembly includes a plurality of permanent magnets 3, and the plurality of permanent magnets 3 correspond to the winding portion 12 one by one, and the permanent magnet 3 is installed at one end of the winding portion 12 close to the track 6; thereby eddy currents are induced on the track 6, thereby generating non-adhesive eddy current braking force; at the same time, the primary and secondary parts of the linear motor are formed with the coil winding assembly 5 on the track 6, thereby realizing dual braking of the train; further, the permanent magnet 3 is arranged in a rectangular shape, and the plurality of permanent magnets 3 adopt a Halbach array; a Halbach array formed by superimposing a radial permanent magnet 3 array and an orthogonal permanent magnet 3 array is used instead of a conventional permanent magnet 3 array, and permanent magnets 3 with different magnetization directions are arranged in a certain order, so that the magnetic field of the array is enhanced on one side and weakened on the other side, and most of the magnetic flux is concentrated at the bottom of the permanent magnet 3, and the braking capacity of the eddy current brake system is significantly improved.

[0035] See also Figure 1-Figure 5 In another embodiment, a plurality of salient pole slots 61 are provided in the length direction of the track 6, and the coil winding assembly 5 is embedded in the plurality of salient pole slots 61 so as to better combine the coil winding assembly 5 with the track 6. Further, the coil winding assembly 5 adopts a fractional slot concentrated full-tooth winding embedded in the salient pole slot 61 located on the track 6. In specific implementation, the windings in the coil winding assembly 5 are arranged in the order of A+, AA-, A+B-, B+B+, B-C+, CC-, C+A-, A+A+, A-B+, BB-, B+C-, C+C+, C-; the primary part is 5 pairs of stages, the secondary track 6 part is 12 slots, the motor copper loss is reduced, and the system braking force fluctuation is reduced; the secondary coil winding assembly 5 adopts a full-tooth structure, a coil is wound on each tooth, the windings are independent of each other in space, the ends are short, and the cost of embedding wire is greatly saved.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. Compound excitation linear eddy current braking system, characterized in that: include: Electromagnetic brake assemblies, permanent magnet brake assemblies and coil winding assemblies; The electromagnetic brake assembly and the permanent magnet brake assembly are both installed at the bottom of the train to induce eddy currents with the track and brake the train; The coil winding assembly is arranged along the length direction of the track, and the coil winding assembly constitutes the secondary part of the linear motor, and the permanent magnet brake assembly constitutes the primary part of the linear motor; so as to brake the train.

2. The composite excitation linear eddy current braking system according to claim 1, characterized in that: The magnitude of the direct current passed into the electromagnetic brake assembly is adjustable.

3. The composite excitation linear eddy current braking system according to claim 1, characterized in that: The phase sequence of the three-phase alternating current flowing into the coil winding assembly can be changed.

4. The composite excitation linear eddy current braking system according to claim 1, characterized in that: The electromagnetic brake assembly includes: an iron core and a DC excitation coil; the iron core includes a connecting portion and a winding portion, a plurality of the winding portions are arranged at intervals along the length direction of the track, and the bottom end of the winding portion is installed on the connecting portion, the other end of the winding portion faces the track, and an air gap is provided between the winding portion and the track; a DC excitation coil is wound around each of the winding portions.

5. The composite excitation linear eddy current braking system according to claim 4, characterized in that: The permanent magnet brake assembly includes a plurality of permanent magnets, the plurality of permanent magnets correspond to the winding parts one by one, and the permanent magnets are installed at one end of the winding part close to the track.

6. The composite excitation linear eddy current braking system according to claim 5, characterized in that: The permanent magnets are arranged in a rectangular shape, and a plurality of the permanent magnets adopt a Halbach array.

7. The composite excitation linear eddy current braking system according to claim 4, characterized in that: A yoke is installed on a side of the connecting portion away from the winding portion.

8. The composite excitation linear eddy current braking system according to claim 7, characterized in that: The yoke is formed by stacking silicon steel sheets.

9. The composite excitation linear eddy current braking system according to claim 1, characterized in that: A plurality of salient pole slots are provided in the length direction of the track, and the coil winding assembly is embedded in the plurality of salient pole slots.

10. The composite excitation linear eddy current braking system according to claim 9, characterized in that: The coil winding assembly adopts a fractional slot concentrated full-tooth winding and is embedded in a salient pole slot located on the track.

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