Speed measurement and positioning system based on single excitation-reception module

Abstract

The application provides a kind of single excitation-receiving module-based speed measurement positioning system, comprising: first, second zero flux coil assembly, excitation receiving module, power supply and signal processing unit, excitation receiving module includes excitation coil, first receiving coil and second receiving coil, excitation coil is set on the first zero flux coil assembly, first receiving coil and second receiving coil are symmetrically set relative to the center line of excitation coil, first receiving coil and second receiving coil are spaced apart on the second zero flux coil assembly, power supply is used to provide direct current to excitation coil, signal processing unit is connected with excitation receiving module, signal processing unit is used to complete the speed measurement and positioning of train according to the first receiving induction voltage of first receiving coil and the second receiving induction voltage of second receiving coil. The technical scheme of the application is used to solve the technical problems of complex speed measurement positioning equipment and large high-speed measurement error in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic levitation train, and particularly relates to a speed measurement and positioning system based on a single excitation-receiving module. BACKGROUND

[0002] The super-speed magnetic levitation train belongs to a track transportation system, and needs to detect and monitor the speed of the train in the running process to provide the position information and speed information of the train at any moment for a traction control system and a train operation control system, which has important guiding significance for train acceleration and deceleration control, operation line regulation or emergency parking. In order to ensure the safe operation of the train, the speed measurement and positioning method needs to be redundantly designed.

[0003] The target positioning and speed measurement system of the super-speed low-vacuum tube magnetic levitation transportation system (T-Flight) is divided into a ground positioning and speed measurement system and a vehicle-mounted positioning and speed measurement system, wherein the ground positioning and speed measurement system provides the position and speed information of the train at any moment for the traction control system and the operation control system; the vehicle-mounted positioning and speed measurement system is completely independent of the ground positioning and speed measurement system, provides the positioning and speed measurement information of the train for a vehicle-mounted operation control unit in the normal operation condition, and is used for displaying the current position and speed for passengers, and in the fault condition of the ground positioning and speed measurement system, is used as a backup guarantee and emergency plan to guide emergency parking.

[0004] At present, there are various technologies to realize positioning and speed measurement, including cross induction return line, Doppler radar, query-responder, pulse width coding and the like. The cross induction return line technology needs complex instruments and equipment, has high construction requirements, needs special treatment for the line intersection section, and has the problems of difficult operation and later maintenance. The Doppler radar has the problem of large high-speed speed measurement error. The query-responder and pulse width coding are suitable for absolute positioning and eliminating cumulative error, and are not suitable for speed measurement. SUMMARY

[0005] The present application provides a speed measurement and positioning system based on a single excitation-receiving module, which can solve the technical problems of complex speed measurement and positioning equipment and large high-speed speed measurement error in the prior art.

[0006] According to an aspect of the present application, there is provided a single excitation-receiving module based speed measurement and positioning system, comprising: a first zero-flux coil assembly and a second zero-flux coil assembly, the first zero-flux coil assembly and the second zero-flux coil assembly are arranged on a train, the first zero-flux coil assembly and the second zero-flux coil assembly are oppositely arranged, and the first zero-flux coil assembly is connected with the second zero-flux coil assembly; an excitation-receiving module, the excitation-receiving module comprises an excitation coil, a first receiving coil and a second receiving coil, the excitation coil is arranged on the first zero-flux coil assembly, the first receiving coil and the second receiving coil are symmetrically arranged with respect to the center line of the excitation coil, and the first receiving coil and the second receiving coil are arranged on the second zero-flux coil assembly with a spacing; a power supply, the power supply is used for providing direct current to the excitation coil; and a signal processing unit, the signal processing unit is connected with the excitation-receiving module, and the signal processing unit is used for completing speed measurement and positioning of the train according to a first receiving induced voltage of the first receiving coil and a second receiving induced voltage of the second receiving coil.

[0007] Further, the spacing between the first receiving coil and the second receiving coil is

[0008] Further, the signal processing unit comprises a signal processing circuit and a digital processor, the signal processing circuit is used for processing the first receiving induced voltage and the second receiving induced voltage to output a square wave voltage difference signal, and the digital processor is used for calculating and obtaining the speed and displacement of the train according to the square wave voltage difference signal.

[0009] Further, the signal processing circuit comprises a subtraction circuit and a zero-crossing detection circuit, the subtraction circuit is used for performing difference operation on the first receiving induced voltage and the second receiving induced voltage to obtain a sinusoidal voltage difference signal, and the zero-crossing detection circuit is used for converting the sinusoidal voltage difference signal into the square wave voltage difference signal.

[0010] Further, the signal processing circuit further comprises an overvoltage protection unit and a filter circuit, the overvoltage protection unit is used for limiting the amplitude of the signal whose voltage exceeds a set voltage threshold range in the first receiving induced voltage and the second receiving induced voltage, and the filter circuit is used for filtering out the signal whose frequency exceeds a set frequency threshold range in the sinusoidal voltage value signal.

[0011] Further, the digital processor comprises a flip-flop, a counter, a timer and an operation unit, the flip-flop is used for triggering according to the square wave voltage difference signal, the counter is used for recording the number of times of triggering of the flip-flop, the timer is used for recording the triggering time interval of the flip-flop, and the operation unit is used for calculating and obtaining the speed and displacement of the train according to the spacing between the adjacent zero-flux coils, the number of times of triggering and the triggering time interval.

[0012] Further, the voltage expression of the overvoltage protection unit is Among them, V i V0 is the input induced voltage, and V1 is the output induced voltage.

[0013] Furthermore, the voltage expression for the zero-crossing detection circuit is: Among them, V j V0' is the input induced voltage of the zero-crossing detection circuit, and V0' is the output induced voltage of the zero-crossing detection circuit.

[0014] Furthermore, the train's speed v i According to Where L is the interval between adjacent zero flux coils, and T i The time interval between the i-th trigger count and the (i-1)-th trigger count.

[0015] Furthermore, the train's displacement S can be calculated using S = iL.

[0016] This invention provides a speed measurement and positioning system based on a single excitation-receiving module. The system utilizes an excitation-receiving module where the excitation coil, carrying direct current, moves forward with the bogie, inducing a current in a first zero-flux coil assembly on the same side. This induced current flows into a second zero-flux coil assembly on the opposite side, generating a magnetic field in the surrounding space. This magnetic field change at the receiving coil of the excitation-receiving module induces an electromotive force in both the first and second receiving coils. Due to their different spatial arrangement, the voltage signals from the first and second receiving coils have a phase difference. The signal processing unit uses this first and second induced voltages to determine the train's speed and positioning. Compared to existing technologies, this speed measurement and positioning system is simple in structure, offers high accuracy at high speeds, and is well-suited for applications such as magnetic levitation rocket skids, electromagnetic catapults, and magnetic levitation aerospace booster launches. Attached Figure Description

[0017] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0018] Figure 1 A schematic diagram of a speed measurement and positioning system based on a single excitation-receiving module according to a specific embodiment of the present invention is shown.

[0019] Figure 2A schematic diagram of a speed measurement and positioning system based on a single excitation-receiving module according to a specific embodiment of the present invention is shown.

[0020] Figures 3a to 3c Three views of an excitation coil (excitation compensation coil) provided according to a specific embodiment of the present invention are shown;

[0021] Figures 4a to 4c A three-view diagram of a first receiving coil (second receiving coil / first receiving compensation coil / second receiving compensation coil) according to a specific embodiment of the present invention is shown;

[0022] Figure 5 A schematic diagram of an overvoltage protection circuit according to a specific embodiment of the present invention is shown;

[0023] Figure 6 A schematic diagram of a subtractor circuit according to a specific embodiment of the present invention is shown;

[0024] Figure 7 A schematic diagram of a low-pass filter provided according to a specific embodiment of the present invention is shown;

[0025] Figure 8 A schematic diagram of a zero-crossing detection circuit according to a specific embodiment of the present invention is shown;

[0026] Figure 9 A schematic diagram illustrating the principle of velocity measurement and positioning based on a single excitation-receiving module according to a specific embodiment of the present invention is shown.

[0027] The above figures include the following reference numerals:

[0028] 10. First zero flux coil assembly; 20. Second zero flux coil assembly; 30. Excitation receiving module; 31. Excitation coil; 32. First receiving coil; 33. Second receiving coil; 40. Power supply; 50. Signal processing unit. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0031] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0032] like Figure 1 and Figure 2 As shown, a speed measurement and positioning system based on a single excitation-receiving module is provided according to a specific embodiment of the present invention. This system includes a first zero-flux coil assembly 10, a second zero-flux coil assembly 20, an excitation-receiving module 30, a power supply 40, and a signal processing unit 50. Both the first zero-flux coil assembly 10 and the second zero-flux coil assembly 20 are mounted on the train, and are arranged opposite to each other. The first zero-flux coil assembly 10 and the second zero-flux coil assembly 20 are connected. The excitation-receiving module 30 includes an excitation coil 31. A first receiving coil 32 and a second receiving coil 33 are provided. An excitation coil 31 is disposed on a first zero flux coil assembly 10. The first receiving coil 32 and the second receiving coil 33 are symmetrically arranged with respect to the center line of the excitation coil 31. The first receiving coil 32 and the second receiving coil 33 are spaced apart on a second zero flux coil assembly 20. A power supply 50 is used to provide DC power to the excitation coil 31. A signal processing unit 60 is connected to the excitation receiving module 30. The signal processing unit 60 is used to complete the speed measurement and positioning of the train based on the first receiving induced voltage of the first receiving coil 32 and the second receiving induced voltage of the second receiving coil 33.

[0033] This configuration provides a speed measurement and positioning system based on a single excitation-receiving module. The system uses an excitation-receiving module where the excitation coil, carrying direct current, moves forward with the bogie, inducing a current in the first zero-flux coil assembly on the same side. This induced current flows into the second zero-flux coil assembly on the opposite side, generating a magnetic field in the surrounding space. This magnetic field change at the receiving coil of the excitation-receiving module induces an electromotive force in both the first and second receiving coils. Due to their different spatial arrangement, the voltage signals from the first and second receiving coils have a phase difference. The signal processing unit uses this first and second induced voltages to determine the train's speed and positioning. Compared to existing technologies, the speed measurement and positioning system provided by this invention has a simple structure, high high-speed speed measurement accuracy, and is well-suited for applications such as magnetic levitation rocket skids, electromagnetic catapults, and magnetic levitation aerospace booster launches.

[0034] Specifically, in this invention, the first zero flux coil assembly 10 and the second zero flux coil assembly 20 are both composed of multiple zero flux coils. The first receiving coil 32 and the second receiving coil 33 are symmetrically arranged with respect to the center line of the excitation coil 31, and their relative positions are fixed. These three coils constitute an excitation-receiving module.

[0035] In this invention, as shown in Figure 3, the pole pitch of the train's propulsion coil is τ, and the distance between the poles is 2τ, which is 360° out of phase with the propulsion coil. In the spatial magnetic field of the ground propulsion coil, the period length of the 2nd harmonic is 2τ / 2, the period length of the 5th harmonic pole pitch is 2τ / 5, and the period length of the 7th harmonic pole pitch is 2τ / 7. When the vehicle body deflects, theoretically, the interference signal cannot be completely canceled. Frequency analysis of the interference signal shows that the 3rd harmonic frequency of the interference signal is half of the actual received signal; the 6th harmonic frequency is the same as the actual received signal. Therefore, the design should try to cancel the interference of the 3rd harmonic as much as possible.

[0036] The period of the signal received using the zero-flux coil counting method is the distance Q between the zero-flux coils divided by the velocity, and the signal frequency is... Where 3Q = τ.

[0037] The third harmonic generated by the propulsion coil on the first and second receiving coils is

[0038] The sixth harmonic generated by the propulsion coil on the first and second receiving coils is

[0039] Since the initial phase of the third harmonic interference signal on the receiving coil changes longitudinally with distance, the rate of change of the initial phase is... That is, the phase changes by 360° for every change in distance τ.

[0040] The third harmonic voltage in the time domain is generated by the magnetic field of the second harmonic of the spatial magnetic field, and the pole distance of the second spatial magnetic field is... The two poles form a pair, with a phase difference of 360° (2π). Therefore, the rate at which the initial phase of the third harmonic changes with spatial position is... Therefore, the spacing between the first receiving coil 32 and the second receiving coil 33 is set to This allows the third harmonics on the first receiving coil 32 and the second receiving coil 33 to be out of phase and cancel each other out.

[0041] As a specific embodiment of the present invention, the pole pitch τ of the propulsion coil is 1.5m, and the distance between the first receiving coil 32 and the second receiving coil 33 is set to 0.75m, so that the third harmonics on the two receiving coils are out of phase and cancel each other out.

[0042] Furthermore, in this invention, in order to obtain the speed and displacement of the train, the signal processing unit 50 can be configured to include a signal processing circuit and a digital processor. The signal processing circuit is used to process the first received induced voltage and the second received induced voltage to output a square wave voltage difference signal, and the digital processor is used to calculate and obtain the speed and displacement of the train based on the square wave voltage difference signal.

[0043] In this invention, the signal processing circuit includes a subtraction circuit and a zero-crossing detection circuit. The subtraction circuit is used to perform a difference operation on the first received induced voltage and the second received induced voltage to obtain a sinusoidal voltage difference signal. The zero-crossing detection circuit is used to convert the sinusoidal voltage difference signal into a square wave voltage difference signal.

[0044] Furthermore, in order to improve the calculation accuracy, the signal processing circuit can be configured to include an overvoltage protection unit and a filtering circuit. The overvoltage protection unit is used to limit the amplitude of signals whose pressure exceeds a set pressure threshold range in the first received induced voltage and the second received induced voltage. The filtering circuit is used to filter out signals whose frequency exceeds a set frequency threshold range in the sinusoidal voltage signal.

[0045] Furthermore, in this invention, the digital processor includes a trigger, a counter, a timer, and an arithmetic unit. The trigger is used to activate based on a square wave voltage difference signal. The counter records the number of times the trigger is activated. The timer records the trigger time interval. The arithmetic unit calculates and obtains the train's speed and displacement based on the interval between adjacent zero flux coils, the number of activations, and the trigger time interval. The train's speed v... i According to Where L is the interval between adjacent zero flux coils, and T iLet S be the time interval between the i-th trigger count and the (i-1)-th trigger count. The train's displacement S can be determined by S = iL.

[0046] To gain a further understanding of the present invention, the following description is provided in conjunction with... Figures 1 to 8 The present invention provides a detailed description of the speed measurement and positioning system based on a single excitation-receiving module.

[0047] like Figures 1 to 8 As shown in the figure, a speed measurement and positioning system based on a single excitation-receiving module is provided according to a specific embodiment of the present invention. The system includes a first zero-flux coil assembly 10, a second zero-flux coil assembly 20, an excitation-receiving module 30, a power supply 40, and a signal processing unit 50. Both the first zero-flux coil assembly 10 and the second zero-flux coil assembly 20 are mounted on the train and are arranged opposite to each other. The first zero-flux coil assembly 10 is connected to the second zero-flux coil assembly 20 via a hinge wire. The excitation-receiving module 30 includes an excitation coil 31, a first receiving coil 32, and a second receiving coil 33. The excitation coil 31 is mounted on the first zero-flux coil assembly 10. Both the first receiving coil 32 and the second receiving coil 33 are connected to the signal processing unit 50. The first receiving coil 32 and the second receiving coil 33 are symmetrically arranged with respect to the center line of the excitation coil 31. The second receiving coil 33 is spaced apart on the second zero flux coil assembly 20. The power supply 40 provides DC power to the excitation coil 31. The signal processing unit 50 completes the speed measurement and positioning of the train based on the first and second receiving induced voltages of the excitation receiving module 30.

[0048] The signal processing unit 50 includes a signal processing circuit and a digital processor. The signal processing circuit processes the first received induced voltage and the second received induced voltage to output a square wave voltage difference signal. The digital processor calculates and obtains the train's speed and displacement based on the square wave voltage difference signal. The signal processing circuit includes a subtraction circuit, a zero-crossing detection circuit, an overvoltage protection unit, and a filtering circuit. The subtraction circuit performs a difference operation on the first received induced voltage and the second received induced voltage to obtain a sinusoidal voltage difference signal. The zero-crossing detection circuit converts the sinusoidal voltage difference signal into a square wave voltage difference signal. The overvoltage protection unit limits the amplitude of signals in the first and second received induced voltages whose pressure exceeds a set pressure threshold range. The filtering circuit filters out signals in the sinusoidal voltage signal whose frequency exceeds a set frequency threshold range. The digital processor includes a trigger, a counter, a timer, and an arithmetic unit. The trigger is activated based on the square wave voltage difference signal. The counter records the number of trigger activations. The timer records the trigger activation time interval. The arithmetic unit calculates and obtains the train's speed and displacement based on the interval between adjacent zero flux coils, the number of trigger activations, and the trigger activation time interval.

[0049] As the bogie moves forward, the excitation coil, carrying direct current, generates an induced current in the first zero flux coil assembly on the same side. This induced current flows into the second zero flux coil assembly on the opposite side, generating a magnetic field in the surrounding space. The change in the magnetic field at the first and second receiving coils of the excitation receiving module induces an electromotive force in them. Due to their different spatial arrangement, the voltage signals of the first and second receiving coils of the excitation receiving module have a phase difference. A square wave waveform is obtained by analyzing the intersection of the first received induced voltage signal from the first receiving coil and the second received induced voltage signal from the second receiving coil. The position and speed information of the train are then calculated based on the square wave waveform.

[0050] The overvoltage protection circuit needs to ensure that the normal operating signal of the receiving coil can be completely input to the subsequent circuitry, but it also needs to perform peak clipping for signals with larger amplitudes or surges. In this embodiment, the voltage expression of the overvoltage protection circuit is: (V i V is the input voltage. o (This refers to the output voltage).

[0051] Subtraction circuits can perform subtraction operations on multiple input signals at different ratios. Figure 6 The circuit shown is a common subtractor circuit. The operational relationship between the input and output of the subtractor circuit is as follows: Wherein, V2 is the induced voltage signal of the receiving compensation coil on the second zero flux coil assembly, V1 is the induced voltage signal of the receiving coil on the first zero flux coil assembly, and R f R1 and R2 are both adjustable resistors, where R2 can be selected according to actual needs. f The value of R1 can be increased when the voltage difference signal is too small. f The value of / R1 is used to amplify the signal.

[0052] The filtering circuit is used to filter out signals in a sinusoidal voltage signal whose frequency exceeds a set frequency threshold range. In this invention, a second-order low-pass filter is designed based on the design process of a Butterworth low-pass filter, and its circuit schematic is shown below. Figure 7 As shown.

[0053] The transfer function of this filter circuit is:

[0054] The circuit gain is

[0055] Where R1, R2, and R3 are resistors, C1 and C2 are capacitors, and s is the transfer function.

[0056] The zero-crossing detection circuit uses a zero-crossing comparator to detect whether an input value is zero. The principle is to ground one input terminal of the integrated operational amplifier and connect the other input terminal to the input voltage for voltage comparison. Near the zero-crossing point of the input voltage, the output voltage changes abruptly. Figure 8 This is the zero-crossing detection circuit used in this embodiment.

[0057] The expression for the zero-crossing detection circuit is: Among them, V j V0' is the input induced voltage of the zero-crossing detection circuit, and V0' is the output induced voltage of the zero-crossing detection circuit.

[0058] The functions of the triggers, counters, and timers are implemented by a digital signal processor (DSP), triggered by the rising edge of the input signal. The counter counts the number of triggers, and the timer measures the trigger time interval. Assume the time interval for the i-th count is T. i If the interval between adjacent zero flux coils is 0.5m, then the velocity v at the current moment is... i for Displacement is Therefore, the train's speed and displacement are calculated based on the interval between adjacent zero flux coils, the number of triggers, and the trigger time interval.

[0059] In summary, this invention provides a speed measurement and positioning system based on a single excitation-receiving module. This system utilizes an excitation-receiving module. The excitation coil, carrying direct current, moves forward with the bogie, inducing a current in the first zero-flux coil assembly on the same side. This induced current flows into the second zero-flux coil assembly on the opposite side, generating a magnetic field in the surrounding space. The change in this magnetic field at the receiving coil of the excitation-receiving module induces an electromotive force in both the first and second receiving coils. Due to their different spatial arrangement, the voltage signals of the first and second receiving coils have a phase difference. The signal processing unit uses the first and second induced voltages from the excitation-receiving module to perform train speed measurement and positioning. Compared with existing technologies, the speed measurement and positioning system provided by this invention has a simple structure, high high-speed speed measurement accuracy, and is well-suited for applications such as magnetic levitation rocket skids, electromagnetic catapults, and magnetic levitation aerospace booster launches.

[0060] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0061] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0062] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A speed measurement and positioning system based on a single excitation-receiving module, characterized in that, The velocity measurement and positioning system based on a single excitation-receiver module includes: A first zero flux coil assembly (10) and a second zero flux coil assembly (20), both the first zero flux coil assembly (10) and the second zero flux coil assembly (20) are installed on the train, the first zero flux coil assembly (10) and the second zero flux coil assembly (20) are arranged opposite to each other, and the first zero flux coil assembly (10) and the second zero flux coil assembly (20) are connected. An excitation receiving module (30) includes an excitation coil (31), a first receiving coil (32), and a second receiving coil (33). The excitation coil (31) is disposed on the first zero flux coil assembly (10). The first receiving coil (32) and the second receiving coil (33) are symmetrically arranged with respect to the center line of the excitation coil (31). The first receiving coil (32) and the second receiving coil (33) are spaced apart on the second zero flux coil assembly (20). A power supply (40) is provided to supply DC power to the excitation coil (31); The signal processing unit (50) is connected to the excitation receiving module (30). The signal processing unit (50) is used to complete the speed measurement and positioning of the train based on the first receiving induced voltage of the first receiving coil (32) and the second receiving induced voltage of the second receiving coil (33).

2. The speed measurement and positioning system based on a single excitation-receiving module according to claim 1, characterized in that, The distance between the first receiving coil (32) and the second receiving coil (33) is τ is the pole pitch of the train's propulsion coil.

3. The speed measurement and positioning system based on a single excitation-receiving module according to claim 1 or 2, characterized in that, The signal processing unit (50) includes a signal processing circuit and a digital processor. The signal processing circuit processes the first received induced voltage and the second received induced voltage to output a square wave voltage difference signal. The digital processor calculates the speed and displacement of the train based on the square wave voltage difference signal.

4. The speed measurement and positioning system based on a single excitation-receiving module according to claim 3, characterized in that, The signal processing circuit includes a subtraction circuit and a zero-crossing detection circuit. The subtraction circuit is used to perform a difference operation on the first received induced voltage and the second received induced voltage to obtain a sinusoidal voltage difference signal. The zero-crossing detection circuit is used to convert the sinusoidal voltage difference signal into a square wave voltage difference signal.

5. The speed measurement and positioning system based on a single excitation-receiving module according to claim 4, characterized in that, The signal processing circuit further includes an overvoltage protection unit and a filtering circuit. The overvoltage protection unit is used to limit the amplitude of signals whose pressure exceeds a set pressure threshold range in the first received induced voltage and the second received induced voltage. The filtering circuit is used to filter out signals whose frequency exceeds a set frequency threshold range in the sinusoidal voltage difference signal.

6. The speed measurement and positioning system based on a single excitation-receiving module according to claim 5, characterized in that, The digital processor includes a trigger, a counter, a timer, and an arithmetic unit. The trigger is used to activate based on the square wave voltage difference signal. The counter is used to record the number of times the trigger is activated. The timer is used to record the trigger time interval. The arithmetic unit is used to calculate and obtain the speed and displacement of the train based on the interval between adjacent zero flux coils, the number of activations, and the trigger time interval.

7. The speed measurement and positioning system based on a single excitation-receiving module according to claim 5, characterized in that, The voltage expression of the overvoltage protection unit is as follows: Among them, V i V0 is the input induced voltage, and V1 is the output induced voltage.

8. The speed measurement and positioning system based on a single excitation-receiving module according to claim 5, characterized in that, The voltage expression for the zero-crossing detection circuit is: Among them, V j V0' is the input induced voltage of the zero-crossing detection circuit, and V0' is the output induced voltage of the zero-crossing detection circuit.

9. The speed measurement and positioning system based on a single excitation-receiving module according to claim 8, characterized in that, The speed v of the train i according to Where L is the interval between adjacent zero flux coils, and T i The time interval between the i-th trigger count and the (i-1)-th trigger count.

10. The speed measurement and positioning system based on a single excitation-receiving module according to claim 9, characterized in that, The displacement S of the train is calculated using S = iL.

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