Method and device for obtaining electromagnetic model of high-speed maglev train

Abstract

The present application discloses a method and a device for obtaining an electromagnetic model of a high-speed maglev train. The method includes: establishing a two-dimensional model of the current of a linear motor in the maglev train, where the two-dimensional model includes unknown current quantities; performing finite element analysis on the working conditions of the maglev train by using the virtual work method to obtain the driving force received by the maglev train; calculating the current values of the unknown current quantities in the two-dimensional model according to the driving force; and obtaining the electromagnetic model of the maglev train according to the current values. It can be seen that, for the method for obtaining the electromagnetic model of the high-speed maglev train provided by the embodiments of the present application, the driving force received by the maglev train under real working conditions can be obtained through the resistance received by the maglev train and the working conditions of the maglev train operation. According to the driving force, the real current values of the maglev train can be calculated, so that an electromagnetic model of the high-speed maglev train that can realize simulation under various real working conditions can be obtained.

Description

Technical Field

[0001] The present application relates to the electromagnetic field, and particularly to a method and device for obtaining an electromagnetic model of a high-speed maglev train. Background Art

[0002] A high-speed maglev train levitates above a guide rail by means of a magnetic field generated by an electric current wound around a linear motor on the guide rail, and also relies on the magnetic field generated by this electric current to generate the driving force for the train to move forward. Therefore, the electromagnetic distribution of a high-speed maglev train will affect the safe operation of the high-speed maglev vehicle. The electromagnetic intensity of a high-speed maglev train will also affect the safety of passengers and equipment on the train.

[0003] At present, high-speed maglev trains are still in the research and development stage, and existing analysis methods and models are usually based on electromagnetic interference analysis under static and single conditions. When a maglev train operates dynamically, the change in its traction field will simultaneously cause a change in the characteristics of electromagnetic interference. Using traditional analysis methods and models can only achieve static single-condition simulation, and it is difficult to achieve simulation of electromagnetic interference under various real conditions. Summary of the Invention

[0004] To solve the above technical problems, the present application provides a method for obtaining an electromagnetic model of a high-speed maglev train, which is used to obtain an electromagnetic model of a high-speed maglev train that can achieve simulation under various real conditions.

[0005] To achieve the above object, the technical solutions provided by the embodiments of the present application are as follows:

[0006] The embodiments of the present application provide a method for obtaining an electromagnetic model of a high-speed maglev train, including: establishing a two-dimensional model of the current of the linear motor in the maglev train, where the two-dimensional model includes unknown current quantities; performing finite element analysis on the conditions of the maglev train by using the virtual work method to obtain the driving force received by the maglev train; calculating the current values of the unknown current quantities in the two-dimensional model according to the driving force; and obtaining the electromagnetic model of the maglev train according to the current values.

[0007] As a possible implementation manner, the calculating the current values of the unknown current quantities in the two-dimensional model according to the driving force includes: obtaining the correspondence between the current and the magnetic field of the maglev train according to the two-dimensional model; and obtaining the current values of the unknown current quantities in the two-dimensional model according to the driving force and the correspondence between the current and the magnetic field of the maglev train.

[0008] As a possible implementation manner, the conditions under which the maglev train operates include the acceleration of the maglev train and the resistance received by the maglev train.

[0009] As a possible implementation, the resistance suffered by the maglev train includes air resistance, and the air resistance is determined according to the gravity and speed of the maglev train.

[0010] As a possible implementation, the resistance suffered by the maglev train includes eddy current resistance, and the eddy current resistance is determined according to the gravity and speed of the maglev train.

[0011] As a possible implementation, the resistance suffered by the maglev train includes ramp resistance, and the ramp resistance is determined according to the gravity of the maglev train and the angle of the ramp where the maglev train is located.

[0012] As a possible implementation, establishing the two-dimensional model of the current of the linear motor in the maglev train includes: establishing a two-dimensional finite element model of the current along the tangential center line of the linear motor in the maglev train.

[0013] As a possible implementation, using the virtual work method to perform finite element analysis on the working conditions of the maglev train to obtain the driving force suffered by the maglev train includes: using the virtual work method to solve the linear motor force or torque of the maglev train to obtain the driving force suffered by the maglev train.

[0014] As a possible implementation, the method provided in the embodiments of the present application further includes: obtaining the electromagnetic peak value of the maglev train according to the electromagnetic model under different working conditions of the maglev train.

[0015] As a possible implementation, the electromagnetic model is a three-dimensional finite element model of electromagnetism.

[0016] The embodiments of the present application also provide a device for obtaining the electromagnetic model of a maglev train, which is characterized in that it includes: a building module for building a two-dimensional model of the current in the maglev train, and the two-dimensional model includes unknown current quantities; a driving force obtaining module for obtaining the driving force suffered by the maglev train according to the resistance suffered by the maglev train and the working conditions of the maglev train; a current obtaining module for calculating the current value of the unknown current quantity in the two-dimensional model according to the driving force; an electromagnetic model obtaining module for obtaining the electromagnetic model of the maglev train according to the current value.

[0017] As a possible implementation, the current obtaining module is specifically used for: obtaining the correspondence between the current and the magnetic field of the maglev train according to the two-dimensional model; obtaining the current value of the unknown current quantity in the two-dimensional model according to the driving force and the correspondence between the current and the magnetic field of the maglev train.

[0018] It can be seen from the above technical solutions that the present application has the following beneficial effects:

[0019] An embodiment of the present application provides a method for obtaining an electromagnetic model of a high-speed maglev train, including: establishing a two-dimensional model of the current of a linear motor in the maglev train, where the two-dimensional model includes unknown current quantities; performing finite element analysis on the operating conditions of the maglev train using the virtual work method to obtain the driving force received by the maglev train; calculating the current value of the unknown current quantity in the two-dimensional model according to the driving force; and obtaining the electromagnetic model of the maglev train according to the current value.

[0020] It can be seen that, for the method for obtaining an electromagnetic model of a high-speed maglev train provided by the embodiment of the present application, the driving force received by the maglev train under real operating conditions can be obtained through the resistance received by the maglev train and the operating conditions of the maglev train. According to the driving force, the real current value of the maglev train can be calculated, so that an electromagnetic model of a high-speed maglev train that can simulate various real operating conditions can be obtained. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a flowchart of a method for obtaining an electromagnetic module of a high-speed maglev train provided by an embodiment of the present application;

[0023] Figure 2 It is a schematic diagram of a TR-type linear motor provided by an embodiment of the present application;

[0024] Figure 3 It is a schematic diagram of a three-dimensional finite element model of the electromagnetic interference characteristics of a maglev train provided by an embodiment of the present application;

[0025] Figure 4 It is a schematic diagram of an electromagnetic model obtaining device of a maglev train provided by an embodiment of the present application. Detailed Embodiments

[0026] In order to help better understand the solution provided by the embodiment of the present application, before introducing the method provided by the embodiment of the present application, the application scenario of the solution of the embodiment of the present application will be introduced first.

[0027] The high-speed maglev train levitates above the guideway relying on the magnetic field generated by the current, and also relies on the magnetic field generated by the current to generate the driving force for the train to move forward. Specifically, the high-speed maglev train is driven by the current wound on the linear motor on the guideway. Therefore, the electromagnetic distribution of the high-speed maglev train will affect the safe operation of the high-speed maglev vehicle. The electromagnetic intensity of the high-speed maglev train will also affect the safety of the passengers and equipment on the train.

[0028] Currently, the high-speed maglev train is still in the research and development stage. The existing analysis methods and models are usually based on the electromagnetic interference analysis under static and single conditions. When the maglev train runs dynamically, the change of its traction force field will simultaneously cause the change of the electromagnetic interference characteristics. Using the traditional analysis methods and models can only achieve the simulation of static and single working conditions, and it is difficult to achieve the simulation of electromagnetic interference under various real working conditions.

[0029] To solve the above technical problems, the embodiment of the present application provides a method for obtaining an electromagnetic model of a high-speed maglev train, including: establishing a two-dimensional model of the current in the maglev train, where the two-dimensional model includes unknown current quantities; obtaining the driving force received by the maglev train according to the resistance received by the maglev train and the working conditions of the maglev train; calculating the current value of the unknown current quantity in the two-dimensional model according to the driving force; and obtaining the electromagnetic model of the maglev train according to the current value.

[0030] It can be seen from this that the method for obtaining an electromagnetic model of a high-speed maglev train provided by the embodiment of the present application can obtain the driving force received by the maglev train under real working conditions through the resistance received by the maglev train and the working conditions of the maglev train. According to this driving force, the real current value of the maglev train can be calculated, so as to obtain an electromagnetic model of the high-speed maglev train that can realize the simulation under various real working conditions.

[0031] To make the above objects, features, and advantages of the present application more obvious and understandable, the following further details the embodiments of the present application in conjunction with the drawings and specific implementation manners.

[0032] See Figure 1 , which is a flowchart of a method for obtaining an electromagnetic module of a high-speed maglev train provided by the embodiment of the present application.

[0033] As Figure 1 shown, the embodiment of the present application provides a method for obtaining an electromagnetic module of a high-speed maglev train, including:

[0034] S101: Establish a two-dimensional model of the current of the linear motor in the maglev train, and the two-dimensional model includes unknown current quantities.

[0035] S102: Adopt the virtual work method to perform finite element analysis on the working conditions of the maglev train to obtain the driving force received by the maglev train.

[0036] S103: Calculate the current value of the current unknown in the two-dimensional model according to the driving force.

[0037] S104: Obtain the electromagnetic model of the maglev train according to the current value.

[0038] As a possible implementation, the corresponding relationship between the current and the magnetic field of the maglev train can be obtained according to the two-dimensional model first; then the current value of the current unknown in the two-dimensional model can be obtained according to the driving force and the corresponding relationship between the current and the magnetic field of the maglev train. In actual applications, the two-dimensional model in the embodiments of the present application can be a two-dimensional finite element model, and the electromagnetic model in the embodiments of the present application is a three-dimensional finite element model of electromagnetism.

[0039] The operating conditions of the maglev train include the acceleration of the maglev train and the resistance suffered by the maglev train. In actual applications, the resistance suffered by the maglev train includes one or more of air resistance, eddy current resistance, ramp resistance and other resistances. Among them, the air resistance of the maglev train is determined according to the gravity and speed of the maglev train. The eddy current resistance of the maglev train is determined according to the gravity and speed of the maglev train.

[0040] When the maglev train is going uphill or downhill, the resistance suffered by the maglev train may also include ramp resistance. It should be noted that the ramp resistance in the embodiments of the present application can be positive or negative. When the maglev train is going uphill, the ramp resistance suffered by the maglev train is positive, and when the maglev train is going downhill, the ramp resistance suffered by the maglev train is negative. Specifically, the ramp resistance of the maglev train is determined according to the gravity of the maglev train and the angle of the ramp where the maglev train is located. The introduction of the air resistance and eddy current resistance in the embodiments of the present application can specifically refer to the following formulas (18) and (19), and the embodiments of the present application will not elaborate here.

[0041] In actual applications, the maglev train may be in various operating conditions. Under different operating conditions, there are also differences in the electromagnetic interference characteristics near the maglev train. For example, when the maglev train is in the uphill state, the maglev train may increase the current in order to obtain greater power, thereby enhancing the electromagnetic interference of the maglev train. In order to determine the safety of the high-speed maglev train, it is necessary to obtain the electromagnetic peak value of the high-speed maglev train, so as to study the impact of the electromagnetic interference of the high-speed maglev train on the on-board equipment and passengers. Therefore, the method provided by the embodiments of the present application can be used to generate electromagnetic models under different operating conditions, so as to obtain the electromagnetic peak value of the maglev train. In actual calculations, the actual situation of the maglev line, that is, the force analysis of the vehicle body, can be combined to calculate the limit values of electrical parameters such as the current required during the operation of the maglev train along the line. Then, an electromagnetic model can be constructed according to the limit value, so as to obtain the electromagnetic peak value of the maglev train.

[0042] The electromagnetic model of the maglev train in the embodiments of the present application can vary according to the model of the linear motor of the maglev train. Taking a TR type linear motor as an example, the method provided in the embodiments of the present application will be introduced below.

[0043] See Figure 2 , which is a schematic diagram of a TR type linear motor provided in the embodiments of the present application.

[0044] As Figure 2 shown, the TR type linear motor provided in the embodiments of the present application can perform two-dimensional finite element analysis along the linear motor section of the tangential center line to study the electromagnetic characteristics of the long stator linear motor.

[0045] The linear motor of the TR type maglev train selects a long-distance rotor to reduce the force fluctuation during the train operation. When using this method, it is necessary to consider the pole pitch of the linear motor stator, the number of pole pairs owned by a magnetic pole module, and the slot pitch of the armature winding slot to determine the rotor pole pitch, as shown in Equation 1:

[0046]

[0047] In the formula, τ m refers to the pole pitch of the rotor, τ1 refers to the pole pitch of the stator; t1 refers to the slot pitch of the stator open slot; p m refers to the number of pole pairs of a magnetic pole module. As an example, the pole pitch of the linear motor stator winding can be 258 mm, and it can be deduced from the above formula that the rotor pole pitch can be 266.5 mm.

[0048] As an example, a long-distance rotor model can be selected based on the finite element analysis of the linear motor, and a complete motor magnetic pole module can be selected for finite element analysis. Suppose this motor magnetic pole module includes 12 stator magnetic poles and 10 rotor magnetic poles. During the train operation, the air-gap magnetic field energy is the source of the kinetic energy of the linear motor rotor, and the change of the rotor force also reflects the change of the air-gap magnetic field from the side. By controlling the air-gap magnetic field, the adjustment of the train traction force and suspension force can be realized. Therefore, based on the force analysis during the train operation, the relationship between the parameters of the synthetic air-gap magnetic field and the traction force and suspension force is determined, so as to determine the limit values of electrical parameters such as armature current required during the train running along the line, and realize the analysis and prediction of the electromagnetic interference characteristics of the whole vehicle.

[0049] Since the change in the air-gap magnetic field is directly reflected in the change in the force on the rotor, further, the traction force and suspension force on the rotor are analyzed to determine the air-gap magnetic field parameters. The changing electromagnetic force is regarded as the virtual displacement of the rotor magnetic pole of the linear motor, and the virtual work method is used to solve the force or torque of the linear motor. The coupled part of the linear motor is regarded as a lossless conservative system, and a single-valued functional relationship is established between various variables, so that the magnetic field energy storage W m becomes the state function of this conservative system, and this function is only related to the final values of various system variables.

[0050] The current state of each variable and the path required to reach the final value are independent of history. The position change x and the magnetic flux Ψ are regarded as the independent variables of this conservative system. Equation (2) is the functional expression of the magnetic field energy storage with respect to these two variables:

[0051]

[0052] In the formula, W m represents the magnetic field energy storage; x represents the position variable from the initial state to the final state; Ψ represents the magnetic flux of each coupled circuit; i represents the magnitude of the current in the coupled circuit.

[0053] Assume that the k-th circuit among n coupled circuits generates a virtual displacement dx k in the time dt. The remaining (n - 1) circuits remain stationary. According to the law of conservation of energy:

[0054] dW Ω = dW m + dW e (3)

[0055] In the formula, dW Ω is the mechanical energy input to the coupled field part; dW m is the change in the magnetic field energy storage in the coupled field; dW e is the change in electrical energy, and the following relationship is satisfied:

[0056] dW Ω = F k dx k (4)

[0057]

[0058]

[0059] In the formula, F k represents the electromagnetic force corresponding to the generation of the virtual displacement, dx k represents the virtual displacement generated by the k-th circuit in the time dt; i i represents the current in the i-th circuit, e irepresents the corresponding induced electromotive force; Ψ i represents the magnetic flux linkage of the i-th coupling circuit.

[0060] The change in magnetic field energy storage dW m also satisfies the following formula:

[0061]

[0062] In the formula, W m is the magnetic field energy storage in the coupling field; dx k represents the virtual displacement generated by the k-th circuit within the time dt; Ψ i represents the magnetic flux linkage of the i-th coupling circuit.

[0063] It can be seen from equations (6) and (7) that the force on the motor rotor in the magnetic field is:

[0064]

[0065] Typically, the virtual work method uses difference quotients to replace derivatives, that is:

[0066]

[0067] In the formula, W′ m1 and W′ m0 respectively represent the magnetic field energy storage in the coupling field at the termination position and the starting position; S1 and S0 represent the termination position and the starting position respectively.

[0068] As can be seen from equation (9), the virtual work method requires two magnetic field calculations to obtain the field values of each unit and calculate the total magnetic co-energy. Finally, the force on the linear motor rotor is obtained from equation (9).

[0069] Based on the force on the linear motor rotor, the electromagnetic parameters forming the air-gap magnetic field of the linear motor are determined. The influencing factors of the synthesized air-gap magnetic field include the magnitude of the armature current, the magnitude of the exciting coil current, the mechanical air-gap size, the motor tooth-slot structure, the power angle of the linear motor, etc.

[0070] The armature winding is supplied with three-phase symmetrical alternating current i A , i B and i C , and the currents of different phase sequences differ by 120 degrees from each other, as shown in equation (2). X, Y, and Z correspond to phases A, B, and C respectively, and the corresponding excitation setting directions are opposite. 300 turns of direct current are passed through the exciting winding. Since the magnitude of the air-gap magnetic field is affected by multiple variables, when controlling the variables, the remaining variables are fixed at the following constant values: the reference value of the mechanical air-gap is 10 mm, the reference value of the amplitude of the three-phase armature winding current I a is 1800 A, and the reference value of the magnitude of the direct current in the exciting winding is 25.7 A.

[0071]

[0072] By establishing a finite element analysis model and cooperating with the mathematical analysis method, the influences of the above-mentioned various factors on the magnitude of the air-gap magnetic field and the influences of the changes of these factors on the traction force and suspension force received by the motor rotor are studied.

[0073] To ensure the accuracy of the finite element analysis, according to the actual structure of the linear motor, an embodiment of the present application selects a motor pole module composed of 12 stator poles and 10 rotor poles for finite element simulation. When a three-phase symmetric alternating current of 1800 A passes through the armature winding in the long stator and a direct current of 25.7 A passes through the 300-turn rotor coil, since the armature magnetic field and the excitation magnetic field are mutually coupled in the air gap between each group of stator and rotor poles of the motor, the air-gap magnetic field of the motor is mainly distributed on each pole. A closed magnetic flux will be formed between each pole and the adjacent group of poles, and the magnetic force is relatively concentrated. Therefore, there are two peaks in the magnetic field distribution of the air gap magnetic field in each group of stator and rotor poles. Generally speaking, the longitudinal component of the magnetic field of the air-gap magnetic field is much larger than its transverse magnetic field component.

[0074] The above-mentioned air-gap magnetic field is formed by the interaction between the DC steady magnetic field formed by the rotor coil and the low-frequency alternating magnetic field formed by the stator winding. The former is called the excitation magnetic field, and the latter is called the armature magnetic field. Therefore, the air-gap magnetic field can be decoupled into the excitation magnetic field and the armature magnetic field for analysis.

[0075] Sample the armature magnetic field distribution of a pair of poles in the center of a pole module, and take the maximum value of the magnetic field therein. The intensity of the armature magnetic field on the pole changes linearly with the armature current.

[0076] The traction force received by the linear motor rotor can be obtained by Equation (11):

[0077]

[0078] In the formula, F x represents the traction force received by the linear motor rotor; H t represents the transverse component of the air-gap magnetic field; H n represents the longitudinal component of the air-gap magnetic field; p represents the total number of pole pairs on one side of the motor; τ s represents the effective length of the stator core; b E represents the effective width of the stator core.

[0079] The air gap of the linear motor for high-speed maglev is large enough compared with the cage motor. Under ideal conditions:

[0080] H t (x,t) = J s (x,t) (12)

[0081] Bm (x,t) = μ0H n (x,t) (13)

[0082] In the formula, J s represents the electric drive current density; B m represents the magnetic induction intensity of the air-gap normal magnetic field; μ0 represents the magnetic permeability in vacuum.

[0083] Assuming that the traction force is constant within a certain motor width, it can be obtained that:

[0084]

[0085] In the formula, p represents the total number of pole pairs on one side of the motor; b E represents the effective width of the stator core; τ s represents the effective length of the stator core; J s represents the stator current per unit length; B m represents the magnetic induction intensity of the air-gap normal magnetic field.

[0086] The stator current per unit length can be deduced from the following formula:

[0087]

[0088] In the formula, I1 represents the fundamental current; τ1 represents the core length; v represents the order of the current harmonic component; k dpv represents the percentage of the corresponding v-th harmonic in the total current; ω represents the angular frequency; x represents the distance of the measurement position relative to the starting position.

[0089] The expression for the thrust generated by the fundamental current I1 is:

[0090]

[0091] In the formula, F x1 represents the thrust generated by the fundamental current; b E represents the effective width of the stator core; k dp1 represents the percentage of the 1st harmonic in the total current; I1 represents the fundamental current.

[0092] It can be seen from formulas (11)-(16) that by adjusting the magnitude of the armature current, and then changing the magnitude of the traveling wave magnetic field, interacting with the excitation magnetic field, the driving force of the train can be changed. The increase in the traction force is due to the increase in the traveling wave magnetic field in the air-gap magnetic field. The linear change of the excitation magnetic field in the traction magnetic field leads to the linear change of the levitation force. The armature magnetic field and the excitation magnetic field are mutually coupled. The change of the armature current will also cause the change of the levitation force on the rotor, but the degree of change is much smaller than that when the magnitude of the excitation magnetic field changes. Therefore, after decoupling, the linear modulation of the levitation force is achieved by changing the excitation current, and the linear modulation of the traction force is achieved by changing the armature current.

[0093] The driving force of the motor varies greatly under the influence of air resistance, eddy current resistance, ramp gravity component, etc., as shown in Equation (17):

[0094] f 总阻力 = f 空气 + f 涡流 + f 坡道 + f 其它 (17)

[0095] The approximate calculation of each part of the resistance is as follows:

[0096]

[0097] f 涡流 = N·(0.1v 0.5 + 0.02v 0.7 ) (19)

[0098] In the formula, N represents the vehicle body gravity; v represents the train operation speed; f 空气 and f 涡流 respectively represent the air resistance and eddy current resistance received by the motor.

[0099] According to the force analysis:

[0100]

[0101] In the formula, F x represents the driving force of the motor; m represents the vehicle body mass; a represents the acceleration of the vehicle body during operation; S represents the distance traveled by the train within time t.

[0102] According to Equation (20), combined with the actual situation of the maglev line and the force analysis of the vehicle body, the limit values of electrical parameters such as the armature current required during the train operation along the line can be calculated. Based on this electrical parameter and Figure 3 the three-dimensional finite element model of the electromagnetic interference characteristics of the maglev train shown, the maximum electromagnetic emission generated by the high-speed maglev train under actual operating conditions can be calculated, realizing the analysis and prediction of the electromagnetic interference characteristics of the whole vehicle.

[0103] According to the method for obtaining the electromagnetic model of the maglev train provided in the above embodiment, the present application embodiment also provides a device for obtaining the electromagnetic model of the maglev train.

[0104] See Figure 4 , this figure is a schematic diagram of a device for obtaining the electromagnetic model of the maglev train provided in the embodiment of the present application.

[0105] A building module 100 is used to build a two-dimensional model of the current in the maglev train, and the two-dimensional model includes current unknowns.

[0106] A driving force acquisition module 200 is configured to acquire the driving force received by the maglev train according to the resistance received by the maglev train and the operating conditions of the maglev train.

[0107] A current acquisition module 300 is configured to calculate the current value of the current unknown in the two-dimensional model according to the driving force.

[0108] An electromagnetic model acquisition module 400 is configured to acquire the electromagnetic model of the maglev train according to the current value.

[0109] As a possible implementation manner, the current acquisition module in the embodiments of the present application may specifically be configured to: obtain the correspondence between the current and the magnetic field of the maglev train according to the two-dimensional model; and obtain the current value of the current unknown in the two-dimensional model according to the driving force and the correspondence between the current and the magnetic field of the maglev train.

[0110] In summary, the electromagnetic model acquisition device for a high-speed maglev train provided in the embodiments of the present application can obtain the driving force received by the maglev train under real operating conditions according to the resistance received by the maglev train and the operating conditions of the maglev train. According to the driving force, the real current value of the maglev train can be calculated, so that an electromagnetic model of the high-speed maglev train that can implement simulations under various real operating conditions can be obtained.

[0111] From the description of the above embodiments, those skilled in the art can clearly understand that all or part of the steps in the above embodiment methods can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network communication device such as a media gateway, etc.) to execute the methods described in each embodiment or some parts of the embodiments of the present application.

[0112] It should be noted that the embodiments in this specification are described in a progressive manner, and the key points of each embodiment are the differences from other embodiments. The same and similar parts between the embodiments can be referred to each other. For the methods disclosed in the embodiments, since they correspond to the systems disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the system part.

[0113] It should also be noted that in this text, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0114] The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but rather is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for obtaining an electromagnetic model of a high-speed maglev train, characterized in that including: establishing a two-dimensional model of the current of a linear motor in a maglev train, the two-dimensional model including unknown current quantities; performing finite element analysis on the working conditions of the maglev train by using the virtual work method to obtain the driving force received by the maglev train; calculating the current values of the unknown current quantities in the two-dimensional model according to the driving force; obtaining the electromagnetic model of the maglev train according to the current values; the calculating the current values of the unknown current quantities in the two-dimensional model according to the driving force includes: obtaining the correspondence between the current and the magnetic field of the maglev train according to the two-dimensional model; obtaining the current values of the unknown current quantities in the two-dimensional model according to the driving force and the correspondence between the current and the magnetic field of the maglev train.

2. The method according to claim 1, characterized in that, The working conditions of the maglev train operation include the acceleration of the maglev train and the resistance received by the maglev train.

3. The method according to claim 2, wherein The resistance received by the maglev train includes air resistance, and the air resistance is determined according to the gravity and speed of the maglev train.

4. The method according to claim 2, characterized in that The resistance received by the maglev train includes eddy current resistance, and the eddy current resistance is determined according to the gravity and speed of the maglev train.

5. The method according to claim 2, wherein The resistance received by the maglev train includes ramp resistance, and the ramp resistance is determined according to the gravity of the maglev train and the angle of the ramp where the maglev train is located.

6. The method according to claim 1, characterized in that, The establishing a two-dimensional model of the current of a linear motor in a maglev train includes: establishing a two-dimensional finite element model of the current along the linear motor profile of the tangential center line of the linear motor in the maglev train.

7. The method according to claim 1, characterized in that, The performing finite element analysis on the working conditions of the maglev train by using the virtual work method to obtain the driving force received by the maglev train includes: solving the linear motor force or torque of the maglev train by using the virtual work method to obtain the driving force received by the maglev train.

8. The method according to claim 1, wherein It also includes: obtaining the electromagnetic peak value of the maglev train according to the electromagnetic model under different working conditions of the maglev train.

9. The method according to any one of claims 1-8, characterized in that, The electromagnetic model is a three-dimensional finite element model of the electromagnetic field.

10. An electromagnetic model acquisition device for a maglev train, characterized in that, including: a establishing module, configured to establish a two-dimensional model of the current in a maglev train, the two-dimensional model including unknown current quantities; a driving force obtaining module, configured to obtain the driving force received by the maglev train according to the resistance received by the maglev train and the working conditions of the maglev train operation; a current obtaining module, configured to calculate the current values of the unknown current quantities in the two-dimensional model according to the driving force; an electromagnetic model obtaining module, configured to obtain the electromagnetic model of the maglev train according to the current values; the current obtaining module is specifically configured to obtain the correspondence between the current and the magnetic field of the maglev train according to the two-dimensional model; and obtain the current values of the unknown current quantities in the two-dimensional model according to the driving force and the correspondence between the current and the magnetic field of the maglev train.

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