CN111114338A

CN111114338A - High-speed maglev train speed measurement sensor and maglev train

Info

Publication number: CN111114338A
Application number: CN202010041689.8A
Authority: CN
Inventors: 吕阳; 胡忠忠; 郑良广; 罗茹丹
Original assignee: Ningbo CRRC Times Transducer Technology Co Ltd
Current assignee: Ningbo CRRC Times Transducer Technology Co Ltd
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2020-05-08
Anticipated expiration: 2040-01-15
Also published as: CN111114338B

Abstract

The invention provides a high-speed maglev train speed measurement sensor and a maglev train, and relates to the technical field of maglev train speed measurement, wherein the high-speed maglev train speed measurement sensor comprises: the magnetic levitation train sensor comprises a sensor body which can be arranged on a magnetic levitation train, at least one probe coil which is arranged on the sensor body and is parallel to a long stator of a magnetic levitation track, and a sampling processing circuit; the probe coil is in a planar spiral shape and is loaded with alternating excitation signals; the sampling processing circuit can process the alternating current signal of the probe coil into a digital signal indicating the impedance change of the probe coil. The high-speed magnetic suspension train speed measurement sensor provided by the invention can be used for carrying out high-precision real-time speed measurement on a magnetic suspension train, and is low in cost.

Description

High-speed maglev train speed measurement sensor and maglev train

Technical Field

The invention relates to the technical field of magnetic suspension train speed measurement, in particular to a high-speed magnetic suspension train speed measurement sensor and a magnetic suspension train.

Background

Magnetic levitation trains have developed into a large direction of future rail transportation technology by virtue of their advantages of no wear, high speed, low noise, etc. Different from the traditional wheel-rail train, the magnetic suspension train keeps floating and hovering with the track during normal operation, and does not rotate mechanically, so the original speed sensor for measuring the rotating speed of the wheels to obtain the speed of the train cannot be applied to the magnetic suspension train.

For a running train, a real-time speed signal must be measured in order to effectively control the running state of the train in real time. In a traditional wheel-rail train, when a vehicle runs, wheels and a steel rail generate mechanical friction to generate forward power, and the number of turns of the wheels is fixed under the condition that the wheels do not slip when the vehicle runs for a fixed distance. Therefore, the current vehicle speed can be obtained by counting the rotation turns of the wheels, converting the rotation turns into the running distance of the vehicle and finally differentiating the time. However, when the maglev train normally runs, the maglev train is suspended at the upper end of the track, and no mechanical contact exists, so that the traditional speed sensor cannot be used.

Chinese patent CN201510429936.0 discloses a magnetic levitation train speed measurement method based on sleeper detection, which comprises the steps of: 1) more than two sleeper detection sensors are sequentially arranged on a train according to a specified distance; after the train starts to run, the step 2) is executed; 2) acquiring the acceleration of the current train operation, and calculating the current train speed according to the acquired acceleration; 3) judging whether the current train speed is in a preset low-speed area, if so, returning to execute the step 2) to perform speed compensation on the low-speed area, and otherwise, executing the step 4); 4) receiving detection signals sent by all sleeper detection sensors in real time, and calculating the current train speed according to the detection signals; and returning to execute the step 3) until the train stops running. In the speed measurement method disclosed in the patent document, since the distance between the sleepers is generally more than 1m, the sensor may not detect the valid signal for a long time when the speed is low, and thus the speed measurement error is large. In addition, the speed measurement scheme needs a plurality of sensors for detection and is matched with a special analysis processing device at the rear end, so that the realization cost is high, the occupied volume is large, and the construction requirement is high; meanwhile, consistency difference, signal processing delay and the like exist among a plurality of sensors, so that the measurement precision is reduced.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a high-speed maglev train speed measurement sensor and a maglev train to measure the speed of the maglev train in real time with high precision and low cost.

The high-speed maglev train speed measurement sensor comprises:

the sensor body can be arranged on a magnetic suspension train;

at least one probe coil which is arranged on the sensor body and is parallel to the long stator of the magnetic suspension track; the probe coil is in a planar spiral shape and is loaded with alternating excitation signals;

a sampling processing circuit; the sampling processing circuit can process the alternating current signal of the probe coil into a digital signal indicating the impedance change of the probe coil.

Further, the high-speed maglev train speed measurement sensor also comprises: an FPGA; the FPFA is used for generating an excitation signal for driving the probe coil;

and the FPGA is also used for calculating the running speed of the magnetic suspension train according to the digital signal output by the sampling processing circuit.

Furthermore, the high-speed maglev train speed measurement sensor specifically comprises a first probe coil and a second probe coil, and the two probe coils are distributed along the motion direction of the maglev train;

the FPGA is also used for judging the motion direction of the magnetic suspension train according to the two paths of digital signals output by the sampling processing circuit; the two paths of digital signals respectively correspond to the first probe coil and the second probe coil.

Furthermore, the FPGA is also used for judging whether a fault exists according to the two paths of digital signals output by the sampling processing circuit.

Further, the speed measurement sensor for the high-speed maglev train further comprises: a digital signal output circuit; the digital signal output circuit is used for processing the speed signal output by the FPGA into a preset format.

Further, the excitation signal is a sinusoidally alternating voltage.

Further, when the high-speed maglev train speed measurement sensor is provided with a plurality of probe coils, the frequencies of excitation signals corresponding to the probe coils are different.

Further, the sampling processing circuit is sequentially provided with: the device comprises a detection circuit, a filter circuit, a signal conditioning circuit and an isolation conversion circuit.

In another aspect, the present invention further provides a magnetic levitation vehicle having the high speed magnetic levitation vehicle velocity sensor.

In the present invention, the speed sensor for high-speed maglev train comprises: the magnetic levitation train sensor comprises a sensor body which can be arranged on a magnetic levitation train, at least one probe coil which is arranged on the sensor body and is parallel to a long stator of a magnetic levitation track, and a sampling processing circuit; alternating excitation signals are loaded on the probe coil; due to the eddy current effect, the probe coil generates equivalent impedance, the equivalent impedance of the probe coil can be changed due to the tooth groove structure on the long track stator, the sampling processing circuit can process alternating current signals of the probe coil into digital signals indicating impedance changes of the probe coil, and the digital signals can be used for calculating speed. Because the width of the tooth socket structure is smaller and far smaller than the interval of the sleeper rails, the speed is judged based on the tooth socket structure, the size of the sensor is effectively reduced, and the measurement precision is greatly improved. In addition, based on the eddy current effect, the sensor response speed is fast, contact is not needed, and the anti-interference capability is strong.

Drawings

Fig. 1 is a structural block diagram of a high-speed maglev train speed measurement sensor in the embodiment of the invention.

FIG. 2 is a schematic diagram of the installation position of a probe coil in the embodiment of the invention.

FIG. 3 is a schematic diagram of a probe coil in an embodiment of the invention.

FIG. 4 is a waveform diagram of a square wave signal corresponding to two probe coils in an embodiment of the invention.

Fig. 5 is a schematic block diagram of a sampling processing circuit in an embodiment of the present invention.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments. In the following description, specific details such as specific configurations and components are provided only to help the full understanding of the embodiments of the present invention. Thus, it will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

The embodiment of the application shows a high-speed maglev train speed measurement sensor which is installed on a maglev train.

As shown in fig. 1, the track of a magnetic levitation train is formed by splicing a standard long stator. The inside silicon steel sheet that is of the long stator of track, outside parcel have the casting glue, and the long stator upper surface of track is the tooth's socket structure of evenly arranging for place the cable, when passing through alternating current in this cable, can produce the magnetic suspension field in the long stator top of track promptly, make whole vehicle liftoff suspension. Wherein, the tooth's socket structure includes tooth structure and groove structure. Typically, the widths of the tooth and slot structures are constant and equal.

In the embodiment of the application, the probe coil is arranged on the high-speed maglev train speed measurement sensor, and when the high-speed maglev train speed measurement sensor passes through the tooth socket structure, the impedance in the probe coil changes periodically.

Referring to fig. 1 and 2, the high speed maglev train tacho sensor 10 includes: the magnetic levitation railway sensor comprises a sensor body 10a capable of being mounted on a magnetic levitation train 20, at least one probe coil 11 and a sampling processing circuit 12, wherein the probe coil 11 is mounted on the sensor body 10a and is arranged in parallel with a long stator 30 of a magnetic levitation railway; the probe coil 11 is in a planar spiral shape and is loaded with alternating excitation signals; the sampling processing circuit 12 may process the ac signal of the probe coil 11 into a digital signal indicative of the impedance change of the probe coil 11.

It should be noted that, when the probe coil is located right above the tooth structure 31, the distance from the probe coil to the metal body is the closest, the eddy current effect is the strongest, the equivalent impedance is the largest, and the amplitude of the signal in the probe coil is the smallest; when the probe coil is positioned above the groove structure 32, the distance from the probe coil to the metal body is farthest, the eddy current effect is weakest, the equivalent impedance is smallest, the amplitude of a signal in the probe coil is largest, and when the coil is positioned at the junction of the tooth groove structure, the amplitude of the signal is centered.

The probe coil 11 is arranged in parallel with the track long stator 30, when the maglev train 20 moves, the equivalent impedance generated by the eddy current effect of the probe coil 11 is periodically changed due to the influence of the tooth socket structure on the track long stator, and meanwhile, the signal amplitude is also periodically changed.

Further, the sampling processing circuit 12 may process the ac signal in the probe coil 11 into a digital signal indicating the impedance change of the probe coil 11, and the obtained digital signal may be used to reflect the equivalent impedance change generated by the eddy current effect. The change period of the equivalent impedance can be obtained through the digital signal, and the change period of the equivalent impedance corresponds to the time of the probe coil 11 passing through one tooth socket structure, so that the number of the passing tooth socket structures in unit time can be obtained, and the moving speed of the probe coil 11, namely the moving speed of the magnetic suspension train along the track can be calculated by combining the width of the tooth socket structures.

In the embodiment of the application, because the width of the tooth space structure is small, the typical value is 43mm, which is far smaller than the interval of the sleeper rail, the speed judgment is carried out based on the tooth space structure, so that the volume of the sensor is effectively reduced, and the measurement accuracy is greatly improved. In addition, based on the eddy current effect, the sensor response speed is fast, contact is not needed, and the anti-interference capability is strong.

Fig. 3 is a schematic structural diagram of a probe coil in an embodiment of the present invention, and the probe coil 11 is a planar spiral. Further, the probe coil 11 is a planar rectangular spiral coil.

In some embodiments, the high speed maglev train tacho sensor 10 further comprises: an FPGA 13; the FPFA13 is used for generating an excitation signal for driving the probe coil 11; the excitation signal may be a high frequency signal.

Further, the excitation signal may be a sinusoidally alternating voltage. It should be noted that the excitation signal may be an alternating signal, and a sinusoidal alternating voltage is a preferred choice.

Furthermore, the FPGA13 is also used for calculating the running speed of the magnetic levitation train 20 according to the digital signal output by the sampling processing circuit.

In some embodiments, the high-speed maglev train tachometer sensor specifically comprises a first probe coil 111 and a second probe coil 112, which are distributed along the moving direction of the maglev train 20; the FPGA13 is further configured to determine a moving direction of the magnetic levitation train 20 according to the two paths of digital signals output by the sampling processing circuit 12; the two paths of digital signals respectively correspond to the first probe coil 111 and the second probe coil 112.

Referring to FIG. 3, the width of each probe coil may correspond to the width of one tooth structure or groove structure, i.e., the widths of the first probe coil 111, the second probe coil 112, the tooth structure 31, and the groove structure 32 are all equal, and may be 43 mm. Further, the two paths of digital signals corresponding to the first probe coil 111 and the second probe coil 112 are square wave signals, and the waveform diagrams are shown in fig. 4. The FPGA obtains square wave signals of two groups of coils, each period represents a tooth socket structure, and the square waves in unit time are counted to obtain the current train running speed. Meanwhile, the driving direction of the train can be judged by judging the front and back directions of the two groups of signals.

In addition, two probe coils are arranged to obtain two paths of digital signals, and the two paths of digital signals can be comprehensively considered, so that errors are reduced, and the speed measurement precision is further improved.

Furthermore, the FPGA is also used for judging whether a fault exists according to the two paths of digital signals output by the sampling processing circuit. The FPGA compares the two groups of speeds, and can judge whether the sensor has a fault. For example, when the speed calculated by the two digital signals is too different, it can be determined that the sensor itself is faulty, and a threshold value of the difference can be set for determining the fault of the sensor.

In some embodiments, the high speed maglev train tachometer sensor further comprises: a digital signal output circuit; the digital signal output circuit is used for processing the speed signal output by the FPGA into a preset format, such as an RS485 data format. The digital signal processed by the digital signal output circuit can be transmitted to a rear-end controller of the maglev train 20.

In some embodiments, when the high-speed maglev train speed measurement sensor is provided with a plurality of probe coils, the frequencies of excitation signals corresponding to the probe coils are different, so that mutual interference among the probe coils can be reduced.

Referring to fig. 5, the sampling processing circuit 12 is provided with: the device comprises a detection circuit, a filter circuit, a signal conditioning circuit and an isolation conversion circuit. The detection circuit is used for multiplying the coil alternating current signal by a standard signal with the same frequency, extracting an envelope curve of the amplitude of the alternating current signal and removing interference signals with other frequencies. After the voltage amplitude is obtained, the maximum value and the minimum value are extracted through processing such as filtering, signal conditioning, amplification and the like, and are isolated and converted into square wave digital signals, so that the FPGA can directly process the square wave digital signals. It should be noted that the maximum value corresponds to the slot structure; the minimum corresponds to the tooth configuration.

The embodiment of the present application also provides a magnetic levitation train, and referring to fig. 1, the magnetic levitation train 20 has a high speed magnetic levitation train speed sensor 10. The maglev train 20 runs on a maglev track, and the high-speed maglev train speed measurement sensor 10 can be used for measuring the speed. The specific content can be seen in the description of the high-speed magnetic suspension train speed measurement sensor 10.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims

1. A high speed maglev train velocity sensor, characterized in that, this high speed maglev train velocity sensor includes:

the sensor body can be arranged on a magnetic suspension train;

2. The sensor for measuring the speed of a high-speed magnetic levitation train as recited in claim 1, further comprising: an FPGA; the FPFA is used for generating an excitation signal for driving the probe coil;

3. The high-speed maglev train speed sensor according to claim 2, wherein the high-speed maglev train speed sensor comprises a first probe coil and a second probe coil, the two probe coils are distributed along the moving direction of the maglev train;

4. The high-speed maglev train speed measurement sensor of claim 3, wherein the FPGA is further configured to determine whether a fault exists according to the two digital signals output by the sampling processing circuit.

5. The high speed maglev train tacho sensor of claim 2, further comprising: a digital signal output circuit; the digital signal output circuit is used for processing the speed signal output by the FPGA into a preset format.

6. The tacho sensor for high speed magnetic levitation trains as claimed in claim 1, wherein the excitation signal is a sinusoidal alternating voltage.

7. The sensor for measuring the speed of a high-speed magnetic levitation train as claimed in claim 1, wherein when the sensor for measuring the speed of a high-speed magnetic levitation train has a plurality of probe coils, the frequencies of the excitation signals corresponding to the probe coils are different.

8. The high-speed maglev train speed measurement sensor according to claim 1, wherein the sampling processing circuit is provided with: the device comprises a detection circuit, a filter circuit, a signal conditioning circuit and an isolation conversion circuit.

9. A magnetic levitation vehicle, characterized in that the magnetic levitation vehicle has a high speed magnetic levitation vehicle tacho sensor according to any of claims 1 to 8.