Magnetic levitation train positioning system and method

Abstract

A system and method for positioning a magnetic levitation train is disclosed, which includes an on-board magnet (1) attached to the bottom of the train, two grating arrays laid in parallel on the train rail along the running direction of the train, an optical pulse generating module (4) and a data processing module (5), each of the two grating arrays includes several sets of magnetic induction gratings, the magnetic induction gratings of the same set in the first grating array (2) have the same central wavelengths, and the magnetic induction gratings of different sets have different central wavelengths, and the magnetic induction gratings of the same set in the second grating array (3) have different central wavelengths, and the gratings at the same arrangement position of the different sets of magnetic induction gratings have the same central wavelengths, and the first grating of each set of magnetic induction gratings serves as a marker grating. The data processing module (5) performs one-stage positioning of the train based on the central wavelength shift status of the marker grating, performs two-stage positioning of the train based on the central wavelength shift status of the first grating array (2), and performs three-stage positioning of the train based on the central wavelength shift status of the second grating array (3), thereby gradually locating the rail position on which the train is running. As a result of the three-stage positioning, the railway position where the train is running can be accurately located, resulting in high positioning accuracy.

Description

[Technical field]

[0001] This application claims priority to a Chinese patent application filed with the China Patent Office on March 4, 2022, bearing application number 202210212795.7 and entitled "Positioning system and method for magnetic levitation trains", the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to the field of magnetic levitation, and more particularly to a system and method for positioning a magnetic levitation train. [Background technology]

[0003] A magnetic levitation train is a train driven by magnetic levitation force, which realizes non-contact levitation and guidance between the train and the railroad by electromagnetic force, and pulls the train to move by the electromagnetic force generated by the linear motor. Magnetic levitation trains float in the air and only encounter air resistance, so they are fast, with high-speed magnetic levitation trains reaching speeds of over 400 kilometers per hour and medium- and low-speed magnetic levitation trains reaching speeds of about 100 to 200 kilometers per hour. However, as the speed of magnetic levitation trains becomes faster and faster, the traditional train positioning solutions can only roughly position the train position, resulting in low positioning accuracy. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, it has become a problem for those skilled in the art to provide a solution to solve the above technical problems.

[0005] The present invention aims to provide a system and method for positioning a magnetic levitation train, which uses three-stage positioning, resulting in accurate positioning of the railway position where the train is running, and has high positioning accuracy. [Means for solving the problem]

[0006] In order to solve the above technical problems, the present invention provides a positioning system for magnetic levitation trains, An on-board magnet attached to the bottom of the train; Two diffraction grating arrays are laid in parallel on a railway line along the running direction of a train, each of the two diffraction grating arrays includes several sets of magnetic induction diffraction gratings, the central wavelengths of the magnetic induction diffraction gratings of the same set in the first diffraction grating array are similar and the central wavelengths of the magnetic induction diffraction gratings of different sets are different, the central wavelengths of the magnetic induction diffraction gratings of the same set in the second diffraction grating array are different, and the central wavelengths of the diffraction gratings at the same arrangement position of the different sets of magnetic induction diffraction gratings are similar, the first diffraction grating of each set of magnetic induction diffraction gratings functions as a marker diffraction grating, and only one diffraction grating in the same diffraction grating array at the same time is affected by the on-board magnet; an optical pulse generating module for providing optical pulse signals to the two diffraction grating arrays, respectively; and a data processing module for performing one-stage positioning of the train based on a central wavelength shift situation of the sign diffraction grating, performing two-stage positioning of the train based on a central wavelength shift situation of a first of the diffraction grating arrays, and performing three-stage positioning of the train based on a central wavelength shift situation of the second of the diffraction grating arrays, thereby locating a railway position on which the train is running in stages.

[0007] Preferably, the optical pulse generating module comprises: a first swept pulse light source that transmits a first optical pulse signal after receiving a trigger signal; a second swept pulse light source that transmits a second optical pulse signal after receiving the trigger signal; a first light pulse amplifier that performs an amplification process on the first light pulse signal to obtain a first light pulse amplified signal; a second light pulse amplifier that performs an amplification process on the second light pulse signal to obtain a second light pulse amplified signal; a first circulator that provides the first optical pulse amplified signal to a first of the diffraction grating arrays; a second circulator that provides the second optical pulse amplified signal to a second of the diffraction grating arrays.

[0008] Preferably, the data processing module comprises: a first optical-to-electrical converter that receives from the first circulator a first optical signal to be detected that is returned by a first diffraction grating array and converts the first optical signal to be detected into a first electrical signal to be detected; a second optical-to-electrical converter that receives from the second circulator a second optical signal to be detected returned by a second grating array and converts the second optical signal to be detected into a second electrical signal to be detected; a data collector that combines and encodes the first target electrical signal and the second target electrical signal to obtain an electrical code signal; and a data processor for decoding the electrical code signal to obtain the first and second electrical signals to be detected, and for performing three-stage positioning of the train based on the diffraction grating center wavelength shift conditions represented by the first and second electrical signals to be detected.

[0009] Preferably, the on-board magnet is formed by combining a plurality of sub-magnets, and the sub-magnets are arranged in accordance with a Halbach array arrangement manner along the running direction of the train.

[0010] Preferably, the pitch between adjacent diffraction gratings in each said grating array is equal to a first predetermined pitch threshold, the pitch between sub-magnets of adjacent rows of said on-board magnet in the direction of travel of the train is equal to a second predetermined pitch threshold, and the total length of said on-board magnet is equal to said first predetermined pitch threshold; The data processing module further determines a target diffraction grating in the second diffraction grating array having a shifted center wavelength and a current train position based on the three-stage positioning of the train, and then determines a distance for the train to continue operating at the current train position based on the center wavelength shift status of the target diffraction grating.

[0011] Preferably, a first said grating array is an O-band grating array and a second said grating array is a C-band grating array.

[0012] Preferably, the data processing module specifically comprises: obtaining a first detection target signal returned by a first of the diffraction grating arrays and a second detection target signal returned by a second of the diffraction grating arrays; determining that the train is traveling on a railway section where a new set of magnetic induction gratings is located when a signal indicative of a shift in the central wavelength of the marker grating is detected from the second detection target signal; When a signal representing a central wavelength shift of any one of the diffraction gratings of a first set of magnetic induction diffraction gratings is detected from the first detection target signal, it is determined that the train is traveling on a railway section where the first set of magnetic induction diffraction gratings is located, and the first set of magnetic induction diffraction gratings is any one of the sets of magnetic induction diffraction gratings in the first diffraction grating array; When a signal representing a center wavelength shift of a target diffraction grating in a second magnetic induction diffraction grating set parallel to the first magnetic induction diffraction grating set is detected from the second detection target signal, it is determined that the onboard magnet location of the train is traveling through a railway position where the target diffraction grating is located, and the target diffraction grating is one of the diffraction gratings in the second magnetic induction diffraction grating set.

[0013] Preferably, the data processing module further comprises: A forward / reverse state of the train within a predetermined railway distance is determined based on a central wavelength shift state of the second diffraction grating array.

[0014] Preferably, the data processing module further comprises: A real-time running speed of the train is determined based on the real-time position change of the train and its running time.

[0015] In order to solve the above technical problems, the present invention further provides a method for positioning a magnetic levitation train, which is applied to any one of the above magnetic levitation train positioning systems, performing one-stage positioning of the train based on the central wavelength shift status of the marker diffraction grating; performing two-stage positioning of the train based on a central wavelength shift situation of the first diffraction grating array; and performing three-stage train positioning based on the central wavelength shift status of the second diffraction grating array to gradually position the railway position where the train is traveling. Effect of the Invention

[0016] The present invention provides a positioning system for magnetic levitation trains, which includes an on-board magnet attached to the bottom of the train, two grating arrays laid in parallel on the train rail along the running direction of the train, an optical pulse generating module, and a data processing module. In the first grating array, the central wavelengths of the same set of magnetic induction gratings are similar, and the central wavelengths of the different sets of magnetic induction gratings are different, and in the second grating array, the central wavelengths of the same set of magnetic induction gratings are different, and the central wavelengths of the gratings at the same arrangement position of the different sets of magnetic induction gratings are similar, and the first grating of each set of magnetic induction gratings serves as a marker grating. The data processing module performs one-stage positioning of the train according to the central wavelength shift situation of the marker grating, performs two-stage positioning of the train according to the central wavelength shift situation of the first grating array, and performs three-stage positioning of the train according to the central wavelength shift situation of the second grating array, thereby gradually positioning the railway position where the train is running. As can be seen, in this application, the three-stage positioning results in the accurate positioning of the railway position where the train is running, and the positioning accuracy is high.

[0017] The present invention further provides a method for positioning a magnetic levitation train, which has the same beneficial effects as the above positioning system. In order to more clearly explain the technical solutions of the embodiments of the present invention, the following briefly introduces the prior art and necessary drawings of the embodiments. The drawings listed below are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings on the premise that they do not make efforts worthy of inventive step. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a structural schematic diagram of a magnetic levitation train positioning system provided by an embodiment of the present invention; [Diagram 2] FIG. 2 is a detailed structural schematic diagram of the magnetic levitation train positioning system provided by an embodiment of the present invention; [Diagram 3] FIG. 2 is a schematic diagram of an arrangement method of a Halbach array provided by an embodiment of the present invention; [Figure 4] FIG. 2 is a schematic diagram of an expansion arrangement method of a Halbach array provided by an embodiment of the present invention; [Diagram 5] FIG. 2 is a diagram illustrating the principle of magnetic induction of two diffraction grating arrays provided by an embodiment of the present invention. [Figure 6] 2 is a flowchart of a positioning method for a magnetic levitation train provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The core of the present invention is to provide a system and method for positioning a magnetic levitation train, which uses three-stage positioning, resulting in accurate positioning of the railway position where the train is running, and has high positioning accuracy.

[0020] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the following clearly and completely describes the technical solutions of the embodiments of the present invention in combination with the drawings of the embodiments of the present invention, and the described embodiments are not all the embodiments, but only some of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without making any inventive efforts are within the scope of protection of the present invention.

[0021] Please refer to FIG. 1, which is a structural schematic diagram of a positioning system for a magnetic levitation train provided by an embodiment of the present invention.

[0022] The magnetic levitation train positioning system includes: An on-board magnet 1 attached to the bottom of the train; Two diffraction grating arrays are laid in parallel on a railway line along the running direction of a train, each of the two diffraction grating arrays includes several sets of magnetic induction diffraction gratings, the central wavelengths of the magnetic induction diffraction gratings of the same set in the first diffraction grating array 2 are similar and the central wavelengths of the magnetic induction diffraction gratings of different sets are different, the central wavelengths of the magnetic induction diffraction gratings of the same set in the second diffraction grating array 3 are different, the central wavelengths of the diffraction gratings at the same arrangement position of the different sets of magnetic induction diffraction gratings are similar, and the first diffraction grating of each set of magnetic induction diffraction gratings functions as a sign diffraction grating, and only one diffraction grating in the same diffraction grating array is affected by the on-board magnet 1 at the same time; an optical pulse generating module 4 for providing optical pulse signals to the two diffraction grating arrays, respectively; and a data processing module 5 for performing one-stage positioning of the train based on the central wavelength shift situation of the marking diffraction grating, performing two-stage positioning of the train based on the central wavelength shift situation of the first diffraction grating array 2, and performing three-stage positioning of the train based on the central wavelength shift situation of the second diffraction grating array 3, thereby locating the railway position where the train is running in stages.

[0023] Specifically, the positioning system of the magnetic levitation train of the present application includes an on-board magnet 1, two grating arrays, an optical pulse generating module 4 and a data processing module 5, and its working principle is as follows: The on-board magnet 1 is installed at the bottom of the train. The two grating arrays are laid in parallel on the train rail along the running direction of the train, and the two grating arrays each include several sets (for example, 16 sets) of magnetic induction gratings, and the number of gratings included in each set of magnetic induction gratings is the same, for example, each set of magnetic induction gratings includes 16 gratings. When the magnetic levitation train runs and passes the grating array, the magnetic induction grating in the grating array is influenced by the on-board magnet 1, and the central wavelength of the optical signal returned by the magnetic induction grating is shifted (each grating location is attached with a small magnetic bead and packaged by a sensitizing structure, and during the train operation, the on-board magnet 1 installed under the body of the magnetic levitation train attracts the small magnetic bead, causing the distortion of the grating and shifting the central wavelength of the grating). Here, within the same diffraction grating array at any one time, only one diffraction grating is affected by the vehicle-mounted magnet 1, and since the two diffraction grating arrays are laid out in parallel, diffraction gratings at the same arrangement position in different diffraction grating arrays at the same time are simultaneously affected by the vehicle-mounted magnet 1; for example, the Nth diffraction grating in the first diffraction grating array 2 and the Nth diffraction grating in the second diffraction grating array 3 are simultaneously affected by the vehicle-mounted magnet 1.

[0024] In the two diffraction grating arrays, the central wavelengths of the magnetic induction diffraction gratings of the same set in the first diffraction grating array 2 are similar, and the central wavelengths of the magnetic induction diffraction gratings of different sets are different. Specifically, the multiple sets of magnetic induction diffraction gratings in the first diffraction grating array 2 are arranged in order of gradually increasing central wavelengths. The center wavelengths of the respective gratings in the same set of magnetic induction diffraction gratings in the second diffraction grating array 3 are different (specifically, the respective gratings in the same set of magnetic induction diffraction gratings in the second diffraction grating array 3 are arranged in the order of gradually increasing center wavelengths), the center wavelengths of the gratings at the same arrangement position in different sets of magnetic induction diffraction gratings are similar (for example, the center wavelength of the Mth diffraction grating of the Nth set of magnetic induction diffraction gratings in the second diffraction grating array 3 is similar to the center wavelength of the Mth diffraction grating of the N+1th set of magnetic induction diffraction gratings in the second diffraction grating array 3), and the first diffraction grating of each set of magnetic induction diffraction gratings in the second diffraction grating array 3 functions as a label diffraction grating (except for the label diffraction grating, all other diffraction gratings in the diffraction grating array use diffraction gratings with a reflectance of 2% or less, and the label diffraction grating uses a low reflectance diffraction grating with a reflectance of 5% to 10%, thereby realizing a distinction from a diffraction grating array having a reflectance of 2% or less, but without significantly attenuating the optical signal).

[0025] The optical pulse generating module 4 provides optical pulse signals to the two grating arrays respectively, and each magnetic induction grating in the two grating arrays returns an optical signal representing its own central wavelength shift status to the data processing module 5. The data processing module 5 first performs one-stage positioning of the train according to the central wavelength shift status of the marking grating, performs two-stage positioning of the train according to the central wavelength shift status of the first grating array 2, and finally performs three-stage positioning of the train according to the central wavelength shift status of the second grating array 3, thereby locating the railway position where the train is running in stages.

[0026] As can be seen from this, in the present application, three-stage positioning results in accurate positioning of the railway position where the train is running, and the positioning accuracy is high.

[0027] Based on the above examples, Please refer to FIG. 2, which is a detailed structural schematic diagram of a positioning system for a magnetic levitation train provided by an embodiment of the present invention.

[0028] In a preferred embodiment, the optical pulse generating module 4 comprises: a first sweep pulse light source 41 that transmits a first optical pulse signal after receiving a trigger signal; a second swept pulse light source 42 that transmits a second optical pulse signal after receiving a trigger signal; a first light pulse amplifier 43 that performs an amplification process on the first light pulse signal to obtain a first light pulse amplified signal; a second light pulse amplifier 44 that performs an amplification process on the second light pulse signal to obtain a second light pulse amplified signal; a first circulator 45 for providing the first optical pulse amplified signal to a first diffraction grating array 2; and a second circulator 46 that provides the second optical pulse amplified signal to a second diffraction grating array 3.

[0029] Specifically, the optical pulse generating module 4 of the present application includes a first swept pulse light source 41, a second swept pulse light source 42, a first optical pulse amplifier 43, a second optical pulse amplifier 44, a first circulator 45 and a second circulator 46, and its operating principle is as follows: After first swept pulse light source 41 receives the trigger signal, it transmits a first optical pulse signal to first optical pulse amplifier 43. First optical pulse amplifier 43 performs an amplification process on the first optical pulse signal to obtain a first optical pulse amplified signal, and transmits the first optical pulse amplified signal to first circulator 45. First circulator 45 provides the first optical pulse amplified signal to first diffraction grating array 2. Second sweep pulse light source 42 and first sweep pulse light source 41 use the same trigger signal. After receiving the trigger signal, second sweep pulse light source 42 transmits a second light pulse signal to second light pulse amplifier 44. Second light pulse amplifier 44 performs an amplification process on the second light pulse signal to obtain a second light pulse amplified signal, and transmits the second light pulse amplified signal to second circulator 46. Second circulator 46 provides the second light pulse amplified signal to second diffraction grating array 3.

[0030] More specifically, the spectrum bandwidth of the two swept pulse light sources can reach more than 40nm, the wavelength scanning step can be adjusted from 10pm to 1nm, the interval between the sweeping periods can be adjusted from 1us to 1ms, the minimum controllable pulse width reaches 1us, and the minimum controllable pulse interval reaches 1us.

[0031] In a preferred embodiment, the data processing module 5 comprises: a first photoelectric converter 51 that receives the first optical signal to be detected returned by the first diffraction grating array 2 from the first circulator 45 and converts the first optical signal to be detected into a first electrical signal to be detected; a second photoelectric converter 52 that receives the second optical signal to be detected returned by the second diffraction grating array 3 from the second circulator 46 and converts the second optical signal to be detected into a second electrical signal to be detected; a data collector 53 for combining and encoding the first target electrical signal and the second target electrical signal to obtain an electrical code signal; and a data processor 54 that decodes the electrical code signal to obtain a first electrical signal to be detected and a second electrical signal to be detected, and performs three-stage positioning of the train based on the central wavelength shift status of the diffraction grating represented by the first electrical signal to be detected and the second electrical signal to be detected.

[0032] Specifically, the data processing module 5 of the present application includes a first photoelectric converter 51, a second photoelectric converter 52, a data collector 53 and a data processor 54, and its working principle is as follows: The first circulator 45 further receives the first optical signal to be detected returned by the first diffraction grating array 2, and transmits the first optical signal to be detected to a first opto-electrical converter 51. The first opto-electrical converter 51 converts the first optical signal to be detected into a first electrical signal to be detected, and transmits the first electrical signal to be detected to a data collector 53. The second circulator 46 also receives the second optical signal to be detected returned from the second diffraction grating array 3 and transmits the second optical signal to be detected to the second opto-electrical converter 52. The second opto-electrical converter 52 converts the second optical signal to be detected into a second electrical signal to be detected and transmits the second electrical signal to the data collector 53. The data collector 53 combines and codes the first and second electric signals to be detected (specifically, combines and codes them in the form of a combined code of superscript+subscript, for example, the first electric signal to be detected corresponding to the Nth diffraction grating in the first diffraction grating array 2 is the superscript of the data, and the second electric signal to be detected corresponding to the Nth diffraction grating in the second diffraction grating array 3 is the subscript of the data), obtains an electric code signal, and transmits the electric code signal to the data processor 54. The data processor 54 decodes the electric code signal to obtain the first and second electric signals to be detected, and performs three-stage positioning of the train based on the central wavelength shift status of the diffraction gratings represented by the decoded first and second electric signals to be detected.

[0033] More specifically, the -3db bandwidth of the two photoelectric converters is DC-500MHz, the rise time is 0.55ns, the gain is 18*103V / W, the saturation optical power is 100uW, the responsivity is 0.9A / W, and high-precision photoelectric conversion can be realized. The data collector can reach 4-channel collection, each channel is 500Ms / s, and the sampling accuracy is 16bit, which can realize high-precision data collection.

[0034] In a preferred embodiment, the vehicle-mounted magnet 1 is formed by combining a number of sub-magnets, which are arranged in the direction of train travel according to a Halbach array arrangement method.

[0035] Specifically, the vehicle-mounted magnet 1 of the present application includes multiple sub-magnets, which are arranged in accordance with a Halbach array arrangement manner along the train running direction, thereby enhancing the magnetic force and improving the sensitivity of the system.

[0036] As shown in FIG. 3, the Halbach array arrangement method (the arrow in the drawing indicates the magnetic field direction) improves the magnetic field strength without reducing the accuracy, and as shown in FIG. 4, the Halbach array extension arrangement method improves the magnetic field strength at the expense of a certain accuracy, making the system more suitable for practical environments.

[0037] In a preferred embodiment, the pitch between adjacent diffraction gratings in each diffraction grating array is equal to a first predetermined pitch threshold, the pitch between sub-magnets of adjacent rows of the vehicle magnet 1 in the direction of travel of the train is equal to a second predetermined pitch threshold, and the total length of the vehicle magnet 1 is equal to the first predetermined pitch threshold; The data processing module 5 further determines a target diffraction grating in the second diffraction grating array 3 whose center wavelength is shifted and a current train position based on the three-stage positioning of the train, and then determines the distance the train will continue to drive at the current train position based on the center wavelength shift situation of the target diffraction grating.

[0038] Specifically, the pitch between adjacent gratings in each grating array of the present application is equal to a predetermined first pitch threshold, that is, the gratings in each grating array are uniformly arranged. In the running direction of the train, the pitch between the sub-magnets of adjacent rows of the vehicle magnet 1 of the present application is equal to a predetermined second pitch threshold, and the total length of the vehicle magnet 1 is equal to the predetermined first pitch threshold, which can ensure that only one grating in the same grating array is affected by the vehicle magnet 1 at the same time.

[0039] Based on this, the data processing module 5 further determines a diffraction grating (called a target diffraction grating) in the second diffraction grating array 3 whose center wavelength is shifted and the current train position based on the three-stage positioning of the train, and then determines the distance the train will continue to drive at the current train position based on the center wavelength shift situation of the target diffraction grating.

[0040] In a preferred embodiment, the first grating array 2 is an O-band grating array and the second grating array 3 is a C-band grating array.

[0041] Specifically, the first diffraction grating array 2 of the present application is an O-band diffraction grating array, the central wavelength of the diffraction grating of the O-band diffraction grating array is 1280-1310nm, and a set of 16 diffraction gratings, and the second diffraction grating array 3 is a C-band diffraction grating array, the central wavelength of the diffraction grating of the C-band diffraction grating array is 1532-1560nm, and a set of 16 diffraction gratings. The diffraction grating array is a weak diffraction grating array, which can realize long-distance installation.

[0042] As shown in FIG. 5, a set of magnetic induction diffraction gratings in the first diffraction grating array 2 and the second diffraction grating array 3 are shown (the principles of the other sets of magnetic induction diffraction gratings are similar, so they will not be described here in detail). Since the center wavelengths of the same set of magnetic induction diffraction gratings in the first diffraction grating array 2 are similar, the set of magnetic induction diffraction gratings in the first diffraction grating array 2 in FIG. 5 are all indicated as O1, and since the center wavelengths of the same set of magnetic induction diffraction gratings in the second diffraction grating array 3 are different, the set of magnetic induction diffraction gratings in the second diffraction grating array 3 in FIG. 5 are respectively indicated as C1-C 16 (Example of combined code method: O1_C1).

[0043] As shown in Figure 5, a simple sub-magnet arrangement scheme (only two magnetic field directions) of the vehicle-mounted magnet 1 is further illustrated. When the vehicle-mounted magnet 1 does not pass through the magnetic induction grating, the central wavelength of the magnetic induction grating does not change, and when any one row of sub-magnets in the vehicle-mounted magnet 1 passes through the magnetic induction grating, the central wavelengths of the magnetic induction grating are affected accordingly (sine change in Figure 5). Based on this, the data processing module 5 further determines the target diffraction grating in the second diffraction grating array 3 whose center wavelength has been shifted and the current train position (the train's on-board magnet location runs over the railway location where the target diffraction grating is located) based on the three-stage positioning of the train, and then determines the distance the train will continue to drive at the current train position based on the number of peaks-troughs of the center wavelength of the target diffraction grating (the distance between adjacent peaks-troughs = the pitch between sub-magnets of adjacent rows of the on-board magnet = a predetermined second pitch threshold, so if N peaks-troughs occur again in the center wavelength of the target diffraction grating, the distance the train will continue to drive = N * predetermined second pitch threshold).

[0044] In a preferred embodiment, the data processing module 5 specifically comprises: obtaining a first detection target signal returned by the first diffraction grating array and a second detection target signal returned by the second diffraction grating array; determining that the train is traveling on a railroad section where a new set of magnetic induction gratings is located when a signal indicative of a shift in the central wavelength of the marker grating is detected from the second detection target signal; When a signal representative of a central wavelength shift of any one of the first gratings in the first grating set is detected from the first detection target signal, it is determined that the train is traveling on the railway section in which the first grating set is located, and the first grating set is any one of the gratings in the first grating array; When a signal representing a center wavelength shift of a target diffraction grating in a second magnetic induction diffraction grating set parallel to the first magnetic induction diffraction grating set is detected from the second detection target signal, it is determined that the onboard magnet location of the train is traveling over a railway position where the target diffraction grating is located, and the target diffraction grating is one of the diffraction gratings in the second magnetic induction diffraction grating set.

[0045] Specifically, the process of the data processing module 5 of the present application performing three-stage train positioning includes: 1) obtaining a first detection target signal returned by a first diffraction grating array and a second detection target signal returned by a second diffraction grating array; 2) determining that the train will run through a railway section where a new set of magnetic induction diffraction gratings is located if a signal representing a central wavelength shift of a marking diffraction grating is detected from the second detection target signal (because the central wavelengths of the marking diffraction gratings of different sets of magnetic induction diffraction gratings in the second diffraction grating array are similar, the central wavelength shift situations of the marking diffraction gratings of different sets of magnetic induction diffraction gratings are similar when applied to the on-board magnet, so when a signal representing a central wavelength shift of a marking diffraction grating is detected from the second detection target signal, it is not possible to know which set of magnetic induction diffraction gratings is specifically applied to the on-board magnet, and since the marking diffraction grating is the first diffraction grating of each set of magnetic induction diffraction gratings, , the train can only determine that it will run on the railway section where a new set of magnetic induction diffraction gratings is located; 3) if a signal representative of a central wavelength shift of any of the sets of magnetic induction diffraction gratings (called the first magnetic induction diffraction grating set) in the first diffraction grating array is detected from the first detection target signal, the train can determine that it will run on the railway section where the first magnetic induction diffraction grating set is located (since the central wavelengths of the same set of magnetic induction diffraction gratings in the first diffraction grating array are similar, when they are applied to the on-board magnet, the central wavelength shift conditions of each diffraction grating of the first magnetic induction diffraction grating set are similar, so if a signal representative of a central wavelength shift of any of the diffraction gratings of the first magnetic induction diffraction grating set is detected from the first detection target signal, it is not possible to know which diffraction grating of which first magnetic induction diffraction grating set is specifically applied to the on-board magnet, and the train can only determine that it will run on the railway section where the first magnetic induction diffraction grating set is located);4) When a signal representing a central wavelength shift of one of the gratings (called a target grating) in the second grating set parallel to the first grating set is detected from the second detection target signal, it is determined that the on-board magnet location of the train is running through the railway position where the target grating is located (since the central wavelengths of the magnetic induction gratings in the same set in the second grating array are different, when they are applied to the on-board magnet, the central wavelength shift conditions of each grating in the same set are different. Therefore, when a signal representing a central wavelength shift of the target grating in the second grating set is detected from the second detection target signal, it is determined that the target grating in the second grating set is applied to the on-board magnet, that is, it is determined that the on-board magnet location of the train is running through the railway position where the target grating is located).

[0046] In addition, the data processing module 5 of the present application further corrects the current train position according to the three-stage positioning of the magnetic levitation train by calculating the speed and the normal delay between the data transmission process, so as to obtain a more accurate train positioning.

[0047] In a preferred embodiment, the data processing module 5 further comprises: Based on the central wavelength shift status of the second diffraction grating array, the forward / reverse status of the train within a given railway distance is determined.

[0048] Furthermore, since the central wavelengths of the same set of magnetic induction diffraction gratings in the second diffraction grating array are different, when the train moves forward or backward, the central wavelengths of the same set of magnetic induction diffraction gratings in the second diffraction grating array will exhibit different changes, so the data processing module 5 of the present application further determines the forward / backward moving status of the train within a short distance (forward: forward running direction; backward: reverse running direction) based on the central wavelength shift status of the second diffraction grating array.

[0049] In a preferred embodiment, the data processing module 5 further comprises: A real-time running speed of the train is determined based on the real-time position change of the train and its running time.

[0050] Furthermore, the data processing module 5 of the present application obtains the real-time position change of the train based on the railway position where the train is running, which is located in real time, and determines the real-time running speed of the train based on the real-time position change of the train and its running time.

[0051] As described above, during the running of the magnetic levitation train, information such as the positioning, speed, running direction, etc. of the magnetic levitation train is obtained through one-stage confirmation by the marking diffraction grating, two-stage confirmation by the same group and same wavelength section of O waves, and three-stage confirmation by the same group and different wavelengths of C waves. The system has the advantages of strong environmental adaptability, high sensitivity, high measurement accuracy, interference resistance and long service life.

[0052] Please refer to FIG. 6, which is a flow chart of a positioning method for a magnetic levitation train provided by an embodiment of the present invention.

[0053] The magnetic levitation train positioning method is applied to any one of the magnetic levitation train positioning systems described above, Step S1: performing one-stage positioning of the train based on the central wavelength shift status of the marker diffraction grating; Step S2 of performing two-stage positioning of the train based on the central wavelength shift status of the first diffraction grating array; and step S3 of performing three-stage positioning of the train based on the central wavelength shift situation of the second diffraction grating array to position the railway position where the train is running in stages.

[0054] For an introduction of the positioning method provided in this application, please refer to the above embodiment of the positioning system, and no further description will be given here.

[0055] Also, here, relational terms such as first and second are used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or sequence between these entities or operations. And, the terms "comprise", "include", "comprise" or any other variant are intended to include a non-exclusive inclusion, whereby a process, method, article, or device that includes a set of elements not only includes those elements, but also includes other elements not expressly listed, or further includes the inherent elements of such process, method, article, or device. Unless further limited, an element defined by the phrase "comprises" does not exclude that the process, method, article, or device that includes the element also includes other identical elements.

[0056] The above description of the disclosed embodiments enables one skilled in the art to realize or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be embodied in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. 1. A magnetic levitation train positioning system, comprising: An on-board magnet attached to the bottom of the train; Two diffraction grating arrays laid in parallel on a railway line along the running direction of a train, each of the two diffraction grating arrays including several sets of magnetic induction diffraction gratings, in which the central wavelengths of the magnetic induction diffraction gratings of the same set in the first diffraction grating array are similar and the central wavelengths of the magnetic induction diffraction gratings of different sets are different, in which the central wavelengths of the magnetic induction diffraction gratings of the same set in the second diffraction grating array are different, and the central wavelengths of the diffraction gratings at the same arrangement position of the different sets of magnetic induction diffraction gratings are similar, the first diffraction grating of each set of magnetic induction diffraction gratings functions as a marker diffraction grating, and only one diffraction grating in the same diffraction grating array at the same time is affected by the on-board magnet; an optical pulse generating module for providing optical pulse signals to the two diffraction grating arrays, respectively; a data processing module for performing one-stage train positioning based on the central wavelength shift status of the marking diffraction grating, performing two-stage train positioning based on the central wavelength shift status of a first of the diffraction grating arrays, and performing three-stage train positioning based on the central wavelength shift status of a second of the diffraction grating arrays, thereby determining a railway position where the train is running in stages; The data processing module specifically includes: obtaining a first detection target signal returned by a first of the diffraction grating arrays and a second detection target signal returned by a second of the diffraction grating arrays; determining that the train is traveling on a railway section where a new set of magnetic induction gratings is located when a signal indicative of a shift in the central wavelength of the marker grating is detected from the second detection target signal; When a signal representing a central wavelength shift of any one of the diffraction gratings of a first set of magnetic induction diffraction gratings is detected from the first detection target signal, it is determined that the train is traveling on a railway section where the first set of magnetic induction diffraction gratings is located, and the first set of magnetic induction diffraction gratings is any one of the sets of magnetic induction diffraction gratings in the first diffraction grating array; A positioning system for a magnetic levitation train, characterized in that when a signal representing a center wavelength shift of a target diffraction grating in a second magnetic induction diffraction grating set parallel to the first magnetic induction diffraction grating set is detected from the second detection target signal, it is determined that the train's on-board magnet location is traveling through a railway position where the target diffraction grating is located, and the target diffraction grating is one of the diffraction gratings in the second magnetic induction diffraction grating set.

2. The optical pulse generating module includes: a first swept pulse light source that transmits a first optical pulse signal after receiving a trigger signal; a second swept pulse light source that transmits a second optical pulse signal after receiving the trigger signal; a first light pulse amplifier that performs an amplification process on the first light pulse signal to obtain a first light pulse amplified signal; a second light pulse amplifier that performs an amplification process on the second light pulse signal to obtain a second light pulse amplified signal; a first circulator that provides the first optical pulse amplified signal to a first of the diffraction grating arrays; 2. The magnetic levitation train positioning system of claim 1, further comprising: a second circulator providing said second light pulse amplified signal to a second of said diffraction grating arrays.

3. The data processing module includes: a first optical-to-electrical converter that receives from the first circulator a first optical signal to be detected that is returned by a first diffraction grating array and converts the first optical signal to be detected into a first electrical signal to be detected; a second optical-to-electrical converter that receives from the second circulator a second optical signal to be detected returned by a second grating array and converts the second optical signal to be detected into a second electrical signal to be detected; a data collector that combines and encodes the first target electrical signal and the second target electrical signal to obtain an electrical code signal; and a data processor for decoding the electrical code signal to obtain the first and second detection target electrical signals, and for performing three-stage positioning of the train based on the diffraction grating center wavelength shift conditions represented by the first and second detection target electrical signals.

4. 2. The magnetic levitation train positioning system of claim 1, wherein the on-board magnet is formed by combining a plurality of sub-magnets, and the plurality of sub-magnets are arranged according to a Halbach array arrangement manner along the running direction of the train.

5. a pitch between adjacent diffraction gratings in each of the grating arrays is equal to a first predetermined pitch threshold, a pitch between sub-magnets of adjacent rows of the on-board magnet in the direction of train travel is equal to a second predetermined pitch threshold, and a total length of the on-board magnet is equal to the first predetermined pitch threshold; The magnetic levitation train positioning system of claim 4, wherein the data processing module further determines a target diffraction grating in the second diffraction grating array having a shifted center wavelength and a current train position based on the three-stage positioning of the train, and then determines a distance for the train to continue operating at the current train position based on the center wavelength shift status of the target diffraction grating.

6. 2. The magnetic levitation train positioning system of claim 1, wherein a first said grating array is an O-band grating array and a second said grating array is a C-band grating array.

7. The data processing module further comprises:

2. The magnetic levitation train positioning system according to claim 1, further comprising a step of determining whether the train is moving forward or backward within a predetermined railway distance based on the central wavelength shift status of the second of the diffraction grating arrays.

8. The data processing module further comprises:

2. The magnetic levitation train positioning system according to claim 1, wherein the real-time running speed of the train is determined based on the real-time position change of the train and its running time.

9. A method for positioning a magnetic levitation train, which is applied to the magnetic levitation train positioning system according to any one of claims 1 to 8, said method comprising the steps of: performing one-stage positioning of the train based on the central wavelength shift status of the marker diffraction grating; performing two-stage positioning of the train based on a central wavelength shift situation of the first diffraction grating array; and performing three-stage positioning of the train based on the central wavelength shift status of the second diffraction grating array to position the railway position where the train is running in stages; The positioning process is specifically as follows: obtaining a first detection target signal returned by a first of the diffraction grating arrays and a second detection target signal returned by a second of the diffraction grating arrays; determining that the train is traveling on a railway section where a new set of magnetic induction gratings is located when a signal indicative of a shift in the central wavelength of the marker grating is detected from the second detection target signal; When a signal representing a central wavelength shift of any one of the diffraction gratings of a first set of magnetic induction diffraction gratings is detected from the first detection target signal, it is determined that the train is traveling on a railway section where the first set of magnetic induction diffraction gratings is located, and the first set of magnetic induction diffraction gratings is any one of the sets of magnetic induction diffraction gratings in the first diffraction grating array; A method for positioning a magnetic levitation train, characterized in that when a signal representing a center wavelength shift of a target diffraction grating in a second magnetic induction diffraction grating set parallel to the first magnetic induction diffraction grating set is detected from the second detection target signal, it is determined that the train's on-board magnet location is traveling through a railway position where the target diffraction grating is located, and the target diffraction grating is one of the diffraction gratings in the second magnetic induction diffraction grating set.

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