Track detection method and system based on eddy current effect

Abstract

The invention discloses a track detection method and system based on the eddy current effect, and belongs to the technical field of track detection. Track defect detection signals and turnout state detection signals are generated by detecting the track state and the turnout state in real time; according to a set analysis rule, the track defect detection signal and the turnout state detection signal are analyzed to obtain a track state and a turnout state, a track defect emergency instruction and a turnout abnormity emergency instruction are generated according to the track state and the turnout state, and a train makes a corresponding response action according to the emergency instructions. On the basis of the eddy current effect, damage to the surface and subsurface of a rail can be detected, fatigue failures such as strain can be detected, the left-right fit degree of a turnout switch rail, a stock rail, a wing rail and a point rail can be detected, whether a point switch works normally or not is judged, whether turnout steering is completed or not is judged, and whether a train can directly pass or not is judged. Safety accidents such as derailment of the train are prevented, and the running safety of the train is improved.

Description

Technical Field

[0001] The present invention relates to the field of track detection technology, and in particular to a track detection method and system based on eddy current effect. Background Art

[0002] Conditions such as rail damage and whether the turnout is completely turned may cause risks such as train derailment, which greatly threatens the safe operation of high-speed trains. Therefore, it is necessary to detect the status of the track in real time to prevent track failures from affecting train operation. Most of the existing track status detection methods use machine vision to identify and classify the track surface and buried defects to obtain the track status. However, this method can only judge the appearance of the track, and in application scenarios such as subway tunnels where light sources are scarce and the running speed is fast, its accuracy and real-time performance are poor. In addition, there is a lack of technical means to identify the turnout status when the train runs to the turnout. The existing turnout identification uses internal signals to determine the turnout steering status, which has poor safety and accuracy. Once the signal is lost, the train will stop in a safe direction, which will ultimately affect the operating efficiency of the entire train line and the safety of the front and rear vehicles. Therefore, a track status detection method with high accuracy, real-time performance and safety is needed.

[0003] Chinese patent, publication number CN113264082B, publication date: June 24, 2022, discloses a high-speed track array ACFM detection probe and its detection method, the device has a signal excitation module, a detection probe, a signal processing module and a host computer; wherein, the signal excitation module is configured to generate a sinusoidal excitation signal; the detection probe is configured to generate an eddy current field on the high-speed track according to the sinusoidal excitation signal, sense the changes in the eddy current field and output a detection signal; the signal processing module is configured to process the detection signal and output the processing result; the host computer is configured to display the processing result, which detects defects in the track through changes in the eddy current field, but it is difficult to detect the switch status at the same time, and its detection range is small. Summary of the invention

[0004] The present invention aims at the problem that it is difficult to accurately detect the track surface state and the turnout state at the same time when detecting the track state in the prior art. The present invention provides a track detection method based on eddy current effect. The method generates a track defect detection signal and a turnout state detection signal by detecting the track state and the turnout state in real time. The track defect detection signal and the turnout state detection signal are analyzed respectively according to a set first analysis rule and a second analysis rule to obtain the track state and the turnout state. A track defect emergency instruction and a turnout abnormality emergency instruction are generated according to the track state and the turnout state. The train makes corresponding response actions to the emergency instructions. Based on the eddy current effect, not only the damage of the track surface and sub-surface can be detected, but also fatigue failure such as strain can be detected. The left and right fit between the turnout point rail and the basic rail, the wing rail and the heart rail can be detected, and it can be judged whether the switch machine is working normally and whether the turnout steering is completed, and then it can be judged whether the train can pass directly, so as to prevent safety accidents such as train derailment, thereby improving the safety of train operation.

[0005] In a first aspect, a technical solution provided in an embodiment of the present invention is: a track detection method based on eddy current effect, comprising the following steps: S1. Based on the eddy current effect, track defect detection signals and turnout status detection signals are obtained respectively; information is exchanged with the switch machine to obtain the fixed and reverse indication signals; S2, based on the first analysis rule, numerically analyzing the track defect detection signal to obtain the track state, and generating a track defect emergency instruction based on the track state; or / and based on the second analysis rule, logically analyzing the turnout state detection signal and the fixed and reverse indication signal to obtain the turnout state, and generating a turnout abnormality emergency instruction based on the turnout state; S3. The train responds to the track defect emergency instruction and / or the turnout abnormality emergency instruction to be directed to the safe side and generates a track inspection report based on the track status and the turnout status.

[0006] In this scheme, by detecting the track in real time, the surface or sub-surface defects of the track, such as crack welds and other abnormal conditions, are judged according to the changes in the acquired track defect detection signal, and the strain of the rail caused by the force can be analyzed based on the changes in the induced current generated by the influence of the magnetic field generated by the eddy current sensing device on the track. According to the analysis results, a targeted maintenance plan can be formulated for the track, which not only improves the detection accuracy of the track state, but also improves the targetedness of the maintenance plan, thereby reducing the maintenance cost; according to the relationship between the acquired turnout state detection signal and the fixed-reverse indication signal, the turnout state is judged when the train runs to the fork road, and it is judged whether the turnout is completely turned, and then it is judged whether the train can pass directly. The control signal of the switch control module and the signal actually detected by the eddy current sensing device are double analyzed, which reduces the probability of false fault alarms, improves the accuracy of turnout state detection, and improves train driving safety.

[0007] Preferably, in S1, obtaining the track defect detection signal and the switch state detection signal based on the eddy current effect respectively includes the following steps: The signal strength, signal waveform and signal phase of the detection signal are obtained based on the eddy current effect, and the above data are statistically analyzed to obtain the track defect detection signal; Detect and count the signal sizes of the detection signals on the left and right sides of the same end of the train to obtain the turnout status detection signal.

[0008] In this scheme, due to the eddy current effect, a magnetic field is generated between the rails, and the rails cut the magnetic field during the operation of the train, thereby generating an induced current inside the rails. By detecting the size, waveform and phase of the induced current, the damage to the surface and sub-surface of the rails and the strain caused by the rail force can be detected. The track state can be detected in real time when the train is running at high speed, and will not be affected by the external environment, thereby improving the accuracy and real-time performance of the track state detection. Since the eddy current sensing device is arranged on both sides of the front and rear ends of the train, when the train is about to enter the turnout, the induced current inside the rails on both sides of the same end of the train will change. By analyzing this change, the turning state of the train can be obtained, providing a comparison basis for the subsequent detection of the turnout state.

[0009] Preferably, in S2, numerically analyzing the track defect detection signal based on the first analysis rule to obtain the track state, and generating a track defect emergency instruction based on the track state, comprises the following steps: When the signal strength of the detection signal continuously decreases for a time period exceeding the set time threshold, the signal strength is analyzed. If the signal strength is less than the signal threshold, it is determined that the track strain state in the detection area is abnormal. When the signal waveform of the detection signal on one side of the train is a sine wave and the signal phases are different, it is determined that the track surface state in the detection area is abnormal; The track strain state and the track surface state are integrated to obtain the track state. When any one of the track strain state and the track surface state is abnormal, the track state is abnormal and a track defect emergency instruction is generated.

[0010] In this solution, when there are defects on the track surface or sub-surface, such as cracks and welds, the waveform and phase of the induced current generated by the eddy current induction device inside the track will fluctuate due to the unevenness of the metal structure. When the track is deformed due to stress, the magnitude of the induced current inside the track will decrease continuously and smoothly. When the decreasing signal exceeds the threshold, it means that the deformation of the track due to stress exceeds the tolerance threshold of the track, and there is a risk of failure. At this time, the train needs to be emergency braked or slowed down to reduce stress and thus reduce the bearing pressure of the track, thereby achieving accurate detection of abnormal conditions of the track due to stress, improving the accuracy of track condition detection, and improving the safety of train operation.

[0011] Preferably, in S2, performing logic analysis on the turnout state detection signal and the turnout indication signal based on the second analysis rule to obtain the turnout state includes the following steps: The signal size of the detection signal on the left and right sides of the same end of the train is obtained, and the level difference between the left and right sides is obtained based on the signal size of the detection signal. Based on the second analysis rule, the level difference between the left and right sides and the fixed and reverse indication signal are logically analyzed, and the turnout state is obtained based on the analysis result.

[0012] In this scheme, since the turnout is controlled by the switch machine when it is turning, the switch machine control module will issue a control instruction on the turning direction. After receiving the control instruction, the switch machine controls the turnout to turn. Therefore, in order to judge the state of the turnout, it is necessary to detect the track turnout during the actual operation of the train. Due to the influence of the turnout turning, the signals detected by the eddy current sensing devices on the left and right sides will produce a level difference. By analyzing the level difference, the turning state and degree of the train can be determined, and then compared with the control instruction on the turning direction issued by the switch machine control module, the effective time of the control and the turning result after the control is completed are determined to determine whether the turnout has completed the turning normally. The double analysis of the control signal of the switch machine control module and the signal actually detected by the eddy current sensing device improves the accuracy of the turnout state detection and improves the train driving safety.

[0013] Preferably, a logic analysis is performed on the level difference between the left and right sides and the fixed reverse indication signal based on the second analysis rule, and the turnout state is obtained based on the analysis result, including the following steps: The fixed and negative indication signals include a fixed indication signal and a negative indication signal. When the level difference between the left and right sides is positive and the fixed indication signal is 1, or the level difference between the left and right sides is negative and the negative indication signal is 1, it is judged that the switch machine is operating normally. If the level difference between the left and right sides is positive and the fixed indication signal is 0, or the level difference between the left and right sides is negative and the reverse indication signal is 0, the train speed is detected. If the train speed does not increase or decrease monotonically, it indicates that the switch machine is operating abnormally. The turnout is analyzed, and whether the turnout state is abnormal is determined based on the analysis results; If the level difference between the left and right sides is not within the normal difference range and the fixed indication signal or the reverse indication signal is 0, it indicates that the switch machine is malfunctioning and the turnout status is abnormal.

[0014] In this scheme, the turning state of the train can be determined based on the positive or negative level difference generated by the signals detected by the eddy current sensing devices on the left and right sides. If the level difference is positive, it represents a right turn, and if the level difference is negative, it represents a left turn. The level difference generated by the train turning is related to the proximity of the point rail and the heart rail in the turnout, representing the degree of turnout turning. If the train can turn normally, the level difference will be in a fixed range. If it is not within this range, it means that the train turning is abnormal, that is, the turnout state is abnormal, and the turnout and switch need to be maintained. The control command issued by the switch control module controls the turning direction of the turnout. If the fixed indication signal is 1, it means that the turnout is controlled to turn right. If the negative indication signal is 1, it means that the turnout is controlled to turn left. By comparing the fixed and negative indication signals with the actually detected turnout state detection signals, the accuracy of turnout state detection is improved, and the train driving safety is improved.

[0015] Preferably, the turnout is analyzed and whether the turnout state is abnormal is determined based on the analysis result, including the following steps: detecting the proximity of the point rail, the base rail and the heart rail in the turnout, if the proximity exceeds a safety threshold, the turnout state is normal; if the proximity is lower than the safety threshold, the turnout state is abnormal.

[0016] In this scheme, since the turnout may not turn completely when it is turning, if the degree of incomplete turning of the turnout is low, it will not affect the normal turning of the train, and there is no need to issue an alarm signal, and the train can operate normally. If the turnout turns correctly but the degree of incomplete turning is high, it will affect the normal turning of the train and an alarm signal needs to be issued to make the train emergency brake or drive into a safe side to prevent safety accidents of the train and ensure the safe operation of the train.

[0017] Preferably, in S3, the train is directed to the safe side in response to the track defect emergency instruction and / or the turnout abnormality emergency instruction and generates a track inspection report based on the track state and the turnout state, including the following steps: If any one of the track status and the turnout status is abnormal, the overall track status is abnormal. Based on the first emergency instruction and / or the second emergency instruction, the train will be guided to the safe side and a track inspection report will be sent. When the track is repaired, the train will be restarted.

[0018] In this solution, when an abnormality occurs at any part of the track or switch, in order to ensure the safety of train operation, the train needs to be guided to the safe side and the track and switch need to be maintained in time. This not only ensures the safety of train operation without affecting the normal operation of other trains, but also greatly ensures the personal safety of passengers.

[0019] In a second aspect, a technical solution provided in an embodiment of the present invention is: a track detection system based on eddy current effect, comprising an eddy current sensing device, a signal processing module, a vehicle assembly module and a switch machine control module; The eddy current sensing device is connected to the signal processing module, and the eddy current sensing device is installed at the front and rear sides of the train through the vehicle assembly module; The signal processing module receives the track defect detection signal collected by the eddy current sensing device, performs numerical analysis on the track defect detection signal based on the first analysis rule to obtain the track state, and generates a track defect emergency instruction based on the track state; The signal processing module receives the turnout state detection signal collected by the eddy current sensor, and exchanges information with the switch machine control module to obtain the turnout state indication signal, performs logic analysis on the turnout state detection signal and the turnout state indication signal based on the second analysis rule to obtain the turnout state, and generates a turnout abnormality emergency instruction based on the turnout state; The train is directed to the safe side in response to the track defect emergency instruction and / or the turnout abnormality emergency instruction and generates a track inspection report based on the track status and the turnout status.

[0020] In this scheme, eddy current sensing devices and signal processing modules are used to detect the status of tracks and switches. In order to improve the detection accuracy, the sensors are reasonably installed at the head and tail of the train and close to the outside of the rails. The data collected in real time during the train operation is sent to the signal processing module and logically judged and decided with the control instructions issued by the switch control module. On the basis of reducing false alarms such as unexplained loss of train meters, it can also complete the real-time detection of dynamic track defects and switch safety status, greatly improving the track detection automation capability and the safety of train operation, thereby reducing the cost of rail operation and maintenance.

[0021] Preferably, the eddy current sensing device comprises a lifting mechanism, an eddy current probe, a fixing frame and a signal transmission line; the lifting mechanism comprises a lifting platform, a ball screw and a small motor; the signal transmission line is connected to the eddy current probe and is arranged in the fixing frame; The small motor is connected to the ball screw; the ball screw is arranged on a lifting platform and connected to the eddy current probe; a lifting thread is provided on the lifting platform, and when the eddy current probe passes through the track connection or generates excessive vibration, the small motor drives the ball screw to adjust the height of the ball screw through the lifting thread provided on the lifting platform to adjust the detection height of the eddy current probe.

[0022] In this scheme, in order to improve the detection accuracy, a lift-off height controllable eddy current sensing device structure is designed. The eddy current probe is fixed to the outside of the rail and connected to the train through a fixing frame and a signal transmission line. At least one detection system is installed on each train, front, back, left, and right. It is fixed to the front and rear frames of the train through a special assembly device, i.e., a fixing frame. The signal transmission line is placed in the hollow inside of the fixing frame. To prevent interference between the detection signal and other signals, a shielding layer can be added outside the signal transmission line. The detection device can directly send the signal to the signal processing module in real time through the cable, thereby completing signal acquisition, and finally identifying the danger and making safety control instructions. There is no need to make any changes to the hardware of the on-board system. Only the same number of IO interfaces as the eddy current sensing device are required to complete the detection task. It is easy to install and the detection method is very simple. It reduces the detection cost while ensuring the detection accuracy, and also improves the detection efficiency.

[0023] Preferably, the detection range of the eddy current sensing device is the depressions on both sides of the track.

[0024] In this solution, the place where the train has the greatest impact on the track during operation is the I-shaped depression of the track. This place is subjected to the stress of the train running all year round and is very prone to deformation and wear. This is the core area that affects the bearing capacity of the track. The relatively overall track state can be obtained by testing this area. Therefore, the detection range of the eddy current sensing device is set to the depressions on both sides of the track to improve the detection accuracy and effect.

[0025] The beneficial effects of the present invention are as follows: (1) The present invention installs eddy current sensing devices on both sides of the train to detect the track in real time, and judges the abnormal state of the surface or sub-surface defects of the track, such as crack welds, based on the changes in the acquired track defect detection signal. The changes in the induced current generated by the influence of the magnetic field generated by the eddy current sensing device on the track can also analyze the strain of the rail caused by the force, and a targeted maintenance plan can be formulated for the track based on the analysis results, which not only improves the detection accuracy of the track state, but also improves the targetedness of the maintenance plan, thereby reducing the maintenance cost; (2) The present invention determines the state of the turnout when the train runs to the fork road based on the relationship between the turnout state detection signal and the control signal obtained by the eddy current sensing device, determines whether the turnout is completely turned, and then determines whether the train can pass directly. The control signal of the switch control module and the signal actually detected by the eddy current sensing device are double analyzed, which reduces the probability of false fault alarms, improves the accuracy of turnout state detection, and improves train driving safety; (3) The present invention designs a highly controllable eddy current sensing device, which can increase the detection range of the sensor and reduce the impact of vibration on detection during train movement, thereby improving detection accuracy.

[0026] The above invention content is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings. The drawings are only for the purpose of illustrating preferred embodiments and are not to be considered as limiting the present invention. Also, the same reference symbols are used throughout the drawings to represent the same parts.

[0028] Figure 1 This is a flow chart of a track detection method based on eddy current effect of the present invention; Figure 2 This is a system block diagram of a track detection system based on eddy current effect of the present invention; Figure 3 This is a schematic diagram of the installation of the eddy current induction device of the present invention; Figure 4 Schematic diagram of the eddy current induction device of the present invention. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the operations (or steps) as sequential processes, many of the operations (or steps) therein can be implemented in parallel, concurrently, or simultaneously. In addition, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but can also have additional steps not included in the drawings; the process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0031] Example 1: Figure 1 As shown, in order to solve the problem that it is difficult to accurately detect the track surface state and the switch state at the same time when detecting the track state in the prior art, this embodiment provides a track state detection method based on eddy current effect, including the following steps: S1: Based on the eddy current effect, the track defect detection signal and the switch status detection signal are obtained respectively; and information is exchanged with the switch machine to obtain the positive and negative indication signal.

[0032] In this embodiment, the track defect detection signal and the switch state detection signal are respectively obtained based on the eddy current effect, including the following steps: The signal strength, signal waveform and signal phase of the detection signal are obtained based on the eddy current effect, and the above data are statistically analyzed to obtain the track defect detection signal; Detect and count the signal sizes of the detection signals on the left and right sides of the same end of the train to obtain the turnout status detection signal.

[0033] In this embodiment, a magnetic field is generated between the rails based on the eddy current effect. During the operation of the train, the rails cut the magnetic field to generate an induced current inside the rails. By detecting the size, waveform and phase of the induced current, the damage to the surface and sub-surface of the rails and the strain caused by the stress on the rails can be detected. The rail state can be detected in real time when the train is running at high speed without being affected by the external environment, thereby improving the accuracy and real-time performance of the rail state detection. Since the eddy current sensing devices are arranged on both sides of the front and rear ends of the train, when the train is about to enter the turnout, the induced current inside the rails on both sides of the same end of the train will change. By analyzing this change, the turning state of the train can be obtained, providing a comparison basis for the subsequent detection of the turnout state.

[0034] S2: numerically analyzing the track defect detection signal based on the first analysis rule to obtain the track state, and generating a track defect emergency instruction based on the track state; or / and logically analyzing the turnout state detection signal and the positive and negative indication signal based on the second analysis rule to obtain the turnout state, and generating a turnout abnormality emergency instruction based on the turnout state;

[0009] In this embodiment, numerical analysis is performed on the track defect detection signal based on the first analysis rule to obtain the track state, and a track defect emergency instruction is generated based on the track state, including the following steps: When the signal strength of the detection signal continuously decreases for a time period exceeding the set time threshold, the signal strength is analyzed. If the signal strength is less than the signal threshold, it is determined that the track strain state in the detection area is abnormal. When the signal waveform of the detection signal on one side of the train is a sine wave and the signal phases are different, it is determined that the track surface state in the detection area is abnormal; The track strain state and the track surface state are integrated to obtain the track state. When any one of the track strain state and the track surface state is abnormal, the track state is abnormal and a track defect emergency instruction is generated.

[0035] When there are defects on the track surface or sub-surface, such as cracks and welds, the unevenness of the metal structure will cause the waveform and phase of the induced current generated by the eddy current induction device inside the track to fluctuate. When the track is deformed due to stress, the magnitude of the induced current inside the track will decrease continuously and smoothly. When the decreasing signal exceeds the threshold, it means that the deformation caused by the stress on the track exceeds the tolerance threshold of the track, and there is a risk of failure. At this time, the train needs to be emergency braked or slowed down to reduce stress and thus reduce the bearing pressure of the track, thereby achieving accurate detection of abnormal conditions of the track due to stress, improving the accuracy of track condition detection, and improving the safety of train operation.

[0036] In this embodiment, performing logic analysis on the turnout state detection signal and the turnout indication signal based on the second analysis rule to obtain the turnout state includes the following steps: The signal size of the detection signal on the left and right sides of the same end of the train is obtained, and the level difference between the left and right sides is obtained based on the signal size of the detection signal. Based on the second analysis rule, the level difference between the left and right sides and the fixed and reverse indication signal are logically analyzed, and the turnout state is obtained based on the analysis result.

[0037] In this embodiment, since the turnout is controlled by the switch machine when it is turning, the switch machine control module will issue a control instruction on the turning direction. After receiving the control instruction, the switch machine controls the turnout to turn. Therefore, in order to judge the state of the turnout, it is necessary to detect the track turnout when the train is actually running. Due to the influence of the turnout turning, the signals detected by the eddy current sensing devices on the left and right sides will produce a level difference. By analyzing the level difference, the turning state and turning degree of the train can be determined, and then compared with the control instruction on the turning direction issued by the switch machine control module, the effective time of the control and the turning result after the control is completed are determined to determine whether the turnout has completed the turning normally. The double analysis of the control signal of the switch machine control module and the signal actually detected by the eddy current sensing device improves the accuracy of the turnout state detection and improves the train driving safety.

[0038] In this embodiment, a logic analysis is performed on the level difference between the left and right sides and the fixed reverse indication signal based on the second analysis rule, and the turnout state is obtained based on the analysis result, including the following steps: The fixed and negative indication signals include a fixed indication signal and a negative indication signal. When the level difference between the left and right sides is positive and the fixed indication signal is 1, or the level difference between the left and right sides is negative and the negative indication signal is 1, it is judged that the switch machine is operating normally. If the level difference between the left and right sides is positive and the fixed indication signal is 0, or the level difference between the left and right sides is negative and the reverse indication signal is 0, the train speed is detected. If the train speed does not increase or decrease monotonically, it indicates that the switch machine is operating abnormally. The turnout is analyzed, and whether the turnout state is abnormal is determined based on the analysis results; If the level difference between the left and right sides is not within the normal difference range and the fixed indication signal or the reverse indication signal is 0, it indicates that the switch machine is malfunctioning and the turnout status is abnormal.

[0039] In this embodiment, the turning state of the train can be determined based on the positive or negative level difference generated by the signals detected by the eddy current sensing devices on the left and right sides. If the level difference is positive, it represents a right turn, and if the level difference is negative, it represents a left turn. The level difference generated by the train turning is related to the proximity of the point rail and the heart rail in the turnout, and represents the degree of turnout turning. If the train can turn normally, the level difference will be in a fixed range. If it is not within this range, it means that the train turning is abnormal, that is, the turnout state is abnormal, and the turnout and switch need to be maintained. The control command issued by the switch control module controls the turning direction of the turnout. If the fixed indication signal is 1, it indicates that the turnout is controlled to turn right. If the negative indication signal is 1, it indicates that the turnout is controlled to turn left. By comparing the fixed and negative indication signals with the actually detected turnout state detection signals, the accuracy of turnout state detection is improved, and the train driving safety is improved.

[0040] In this embodiment, the turnout is analyzed, and whether the turnout state is abnormal is determined based on the analysis result, including the following steps: detecting the proximity of the point rail, the base rail and the heart rail in the turnout, if the proximity exceeds the safety threshold, the turnout state is normal; if the proximity is lower than the safety threshold, the turnout state is abnormal.

[0041] In this embodiment, when the turnout is turning, the turnout may not turn completely. If the degree of incomplete turning of the turnout is low, it will not affect the normal turning of the train, and there is no need to issue an alarm signal, so the train can operate normally. If the turnout turns correctly but the degree of incomplete turning is high, it will affect the normal turning of the train, and an alarm signal needs to be issued to make the train emergency brake or drive into a safe side to prevent safety accidents of the train and ensure the safe operation of the train.

[0042] S3: The train is directed to a safe side in response to the track defect emergency instruction and / or the turnout abnormality emergency instruction and generates a track inspection report based on the track status and the turnout status.

[0043] In this embodiment, the train responds to the track defect emergency instruction and / or the turnout abnormality emergency instruction to guide to the safe side and generates a track detection report based on the track state and the turnout state, including the following steps: If any one of the track status and the turnout status is abnormal, the overall track status is abnormal. Based on the first emergency instruction and / or the second emergency instruction, the train will be guided to the safe side and a track inspection report will be sent. When the track is repaired, the train will be restarted.

[0044] In this embodiment, when an abnormality occurs at any part of the track or the switch, in order to ensure the safety of train operation, the train needs to be guided to the safe side and the track needs to be maintained in time. This not only ensures the safety of train operation without affecting the normal operation of other trains, but also greatly ensures the personal safety of passengers.

[0045] This embodiment detects the track in real time, and judges the abnormal conditions of the surface or sub-surface defects of the track, such as cracks and welds, according to the changes in the acquired track defect detection signal. The strain of the rail caused by the force can also be analyzed based on the changes in the induced current generated by the influence of the magnetic field generated by the eddy current sensing device on the track. A targeted maintenance plan can be formulated for the track based on the analysis results, which not only improves the detection accuracy of the track state, but also improves the targetedness of the maintenance plan, thereby reducing the maintenance cost; based on the relationship between the acquired turnout state detection signal and the fixed-reverse indication signal, the turnout state is judged when the train runs to the fork road, and it is judged whether the turnout is completely turned, and then it is judged whether the train can pass directly. The control signal of the switch control module and the signal actually detected by the eddy current sensing device are double analyzed, which reduces the probability of false fault alarms, improves the accuracy of turnout state detection, and improves train driving safety.

[0046] Example 2: Figure 2 and Figure 3 As shown, this embodiment also provides a track state detection system based on eddy current effect, including an eddy current sensing device, a signal processing module, a vehicle assembly module and a switch machine control module; The eddy current sensing device is connected to the signal processing module, and the eddy current sensing device is installed at the front and rear sides of the train through the vehicle assembly module; The signal processing module receives the track defect detection signal collected by the eddy current sensing device, performs numerical analysis on the track defect detection signal based on the first analysis rule to obtain the track state, and generates a track defect emergency instruction based on the track state; The signal processing module receives the turnout state detection signal collected by the eddy current sensor, and exchanges information with the switch machine control module to obtain the turnout state indication signal, performs logic analysis on the turnout state detection signal and the turnout state indication signal based on the second analysis rule to obtain the turnout state, and generates a turnout abnormality emergency instruction based on the fork and knife state; The train is directed to the safe side in response to the track defect emergency instruction and / or the turnout abnormality emergency instruction and generates a track inspection report based on the track status and the turnout status.

[0047] This embodiment uses an eddy current sensing device and a signal processing module to detect the overall state of the track. In order to improve the detection accuracy, the sensor is reasonably installed at the head and tail of the train and close to the outside of the rail. The data collected in real time during the train operation is sent to the signal processing module and logically judged and decided with the control instructions issued by the switch control module. On the basis of reducing false alarms such as unexplained loss of the train, it can also complete the real-time detection of dynamic track defects and the safety status of switches, greatly improving the track detection automation capability and the safety of train operation, thereby reducing the cost of rail operation and maintenance.

[0048] like Figure 4 As shown, the eddy current sensing device includes a lifting mechanism, an eddy current probe, a fixing frame and a signal transmission line; the lifting mechanism includes a lifting platform, a ball screw and a small motor; the signal transmission line is connected to the eddy current probe and is arranged in the fixing frame; The small motor is connected to the ball screw; the ball screw is arranged on a lifting platform and connected to the eddy current probe; a lifting thread is provided on the lifting platform, and when the eddy current probe passes through the track connection or generates excessive vibration, the small motor drives the ball screw to adjust the height of the ball screw through the lifting thread provided on the lifting platform to adjust the detection height of the eddy current probe.

[0049] In order to improve the detection accuracy, this embodiment designs an eddy current sensing device structure with controllable lifting height. The eddy current probe is fixed to the outside of the rail and connected to the train through a fixing frame and a signal transmission line. At least one detection system is installed on each train, front, back, left, and right. It is fixed to the front and rear frames of the train through a special assembly device, i.e., a fixing frame. The signal transmission line is placed in the hollow inside of the fixing frame. In order to prevent interference between the detection signal and other signals, a shielding layer can be added outside the signal transmission line. The detection device can directly send the signal to the signal processing module in real time through the cable, thereby completing signal acquisition, and finally identifying the danger and making safety control instructions. There is no need to make any changes to the hardware of the on-board system. Only the same number of IO interfaces as the eddy current sensing device are required to complete the detection task. It is easy to install and the detection method is very simple. It reduces the detection cost while ensuring the detection accuracy, and also improves the detection efficiency.

[0050] In order to obtain high-precision dynamic data collection, this embodiment may stipulate that the number of rail collection times is at least 10,000 times per meter. Since the train is in dynamic operation at all times, its speed will change greatly. Therefore, the fastest speed of the train is used as the collection standard. If the train is entering the station or stops for 3 seconds (when the speed sensor is 0m / s), the signal processing module will automatically stop processing the data sent by the eddy current sensing device.

[0051] In this embodiment, the detection range of the eddy current sensing device is the depressions on both sides of the track.

[0052] In this embodiment, the place where the track is most affected during the operation of the train is the I-shaped depression of the track. This place is subjected to the stress of the train running all year round and is very prone to deformation and wear. This is the core area that affects the bearing capacity of the track. The relatively overall track state can be obtained by detecting this place. Therefore, the detection range of the eddy current sensing device is set to the depressions on both sides of the track to improve the detection accuracy and effect.

[0053] In this embodiment, since the rails are connected by large bolts and nuts, and the nuts protrude from the outside of the rails, the distance between the eddy current probe and the rails will bring challenges to the actual real-time detection, that is, the distance is large and the lifting height is too high, resulting in reduced detection accuracy. When the distance is small, the outer nut will collide with the probe ball. In order to prevent the vibration during the train operation from affecting the lifting height, the eddy current probe structure in this embodiment adds an automatic lifting function. Whenever the sensor passes through the rail connection or a large vibration occurs, the signal processing module will issue a small motor control instruction, and the motor can move the support frame by driving the ball screw. This structure can improve the detection accuracy under actual working conditions. The left and right sides of the front and rear of the train are fixed to the concave part of the rail by T-shaped fixing frames. Due to the thin thickness of this part, in addition to the vertical pressure of the wheel, it also bears the lateral horizontal force of the wheel, especially the heart rail near the harmful space of the fork part. The wing rail bears a large train impact force, which is a common part of rail damage. Therefore, the eddy current probe is installed in this part to obtain the best detection effect.

[0054] It can be seen from the above embodiments that at least the following substantial effects are achieved: (1) The present invention installs eddy current sensing devices on both sides of the train to detect the track in real time. The surface or sub-surface defects of the track, such as cracks and welds, are judged based on the changes in the acquired track defect detection signal. The strain of the rail caused by the force can also be analyzed based on the changes in the induced current generated by the magnetic field generated by the eddy current sensing device on the track. A targeted maintenance plan can be formulated for the track based on the analysis results, which not only improves the detection accuracy of the track status, but also improves the targetedness of the maintenance plan, thereby reducing the maintenance cost; (2) The present invention determines the state of the turnout when the train runs to the fork road based on the relationship between the turnout state detection signal and the control signal obtained by the eddy current sensing device, determines whether the turnout is completely turned, and then determines whether the train can pass directly. The control signal of the switch control module and the signal actually detected by the eddy current sensing device are double analyzed, which reduces the probability of false fault alarms, improves the accuracy of turnout state detection, and improves train driving safety; (3) The present invention designs a highly controllable eddy current sensing device, which can increase the detection range of the sensor and reduce the impact of vibration on detection during train movement, thereby improving detection accuracy.

[0055] The specific implementation described above is a preferred implementation of a track state detection method and system based on eddy current effect of the present invention, and is not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to this specific implementation. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A track detection method based on eddy current effect, characterized in that: The following steps are involved: S1. Based on the eddy current effect, track defect detection signals and turnout status detection signals are obtained respectively; information is exchanged with the switch machine to obtain the fixed and reverse indication signals; S2, based on the first analysis rule, numerically analyzing the track defect detection signal to obtain the track state, and generating a track defect emergency instruction based on the track state; or / and based on the second analysis rule, logically analyzing the turnout state detection signal and the fixed and reverse indication signal to obtain the turnout state, and generating a turnout abnormality emergency instruction based on the turnout state; S3. The train responds to the track defect emergency instruction and / or the turnout abnormality emergency instruction to be directed to the safe side and generates a track inspection report based on the track status and the turnout status.

2. A track detection method based on eddy current effect according to claim 1, characterized in that: In S1, the track defect detection signal and the switch state detection signal are respectively obtained based on the eddy current effect, including the following steps: The signal strength, signal waveform and signal phase of the detection signal are obtained based on the eddy current effect, and the above data are statistically analyzed to obtain the track defect detection signal; Detect and count the signal sizes of the detection signals on the left and right sides of the same end of the train to obtain the turnout status detection signal.

3. A track detection method based on eddy current effect according to claim 1, characterized in that: In S2, numerical analysis is performed on the track defect detection signal based on the first analysis rule to obtain the track state, and a track defect emergency instruction is generated based on the track state, including the following steps: When the signal strength of the detection signal continuously decreases for a time period exceeding the set time threshold, the signal strength is analyzed. If the signal strength is less than the signal threshold, it is determined that the track strain state in the detection area is abnormal. When the signal waveform of the detection signal on one side of the train is a sine wave and the signal phases are different, it is determined that the track surface state in the detection area is abnormal; The track strain state and the track surface state are integrated to obtain the track state. When any one of the track strain state and the track surface state is abnormal, the track state is abnormal and a track defect emergency instruction is generated.

4. A track detection method based on eddy current effect according to claim 1, characterized in that: In S2, based on the second analysis rule, the turnout state detection signal and the turnout indication signal are logically analyzed to obtain the turnout state, including the following steps: The signal size of the detection signal on the left and right sides of the same end of the train is obtained, and the level difference between the left and right sides is obtained based on the signal size of the detection signal. Based on the second analysis rule, the level difference between the left and right sides and the fixed and reverse indication signal are logically analyzed, and the turnout state is obtained based on the analysis result.

5. A track detection method based on eddy current effect according to claim 4, characterized in that: Based on the second analysis rule, the level difference between the left and right sides and the fixed reverse indication signal are logically analyzed, and the turnout state is obtained based on the analysis result, including the following steps: The fixed and negative indication signals include a fixed indication signal and a negative indication signal. When the level difference between the left and right sides is positive and the fixed indication signal is 1, or the level difference between the left and right sides is negative and the negative indication signal is 1, it is judged that the switch machine is operating normally. If the level difference between the left and right sides is positive and the fixed indication signal is 0, or the level difference between the left and right sides is negative and the reverse indication signal is 0, the train speed is detected. If the train speed does not increase or decrease monotonically, it indicates that the switch machine is operating abnormally. The turnout is analyzed, and whether the turnout state is abnormal is determined based on the analysis results; If the level difference between the left and right sides is not within the normal difference range and the fixed indication signal or the reverse indication signal is 0, it indicates that the switch machine is malfunctioning and the turnout status is abnormal.

6. A track detection method based on eddy current effect according to claim 5, characterized in that: Analyzing the turnout and judging whether the turnout state is abnormal based on the analysis result includes the following steps: Detect the proximity of the point rail, the base rail and the heart rail in the turnout. If the proximity exceeds the safety threshold, the turnout is in a normal state; if the proximity is lower than the safety threshold, the turnout is in an abnormal state.

7. A track detection method based on eddy current effect according to claim 1, characterized in that: In S3, the train responds to the track defect emergency instruction and / or the turnout abnormality emergency instruction to guide to the safe side and generates a track inspection report based on the track state and the turnout state, including the following steps: If any one of the track status and the turnout status is abnormal, the overall track status is abnormal. Based on the first emergency instruction and / or the second emergency instruction, the train will be guided to the safe side and a track inspection report will be sent. When the track is repaired, the train will be restarted.

8. A track detection system based on eddy current effect, applicable to a track detection method based on eddy current effect as claimed in any one of claims 1 to 7, characterized in that: It includes an eddy current sensing device, a signal processing module, a vehicle assembly module and a switch machine control module; The eddy current sensing device is connected to the signal processing module, and the eddy current sensing device is installed at the front and rear sides of the train through the vehicle assembly module; The signal processing module receives the track defect detection signal collected by the eddy current sensing device, performs numerical analysis on the track defect detection signal based on the first analysis rule to obtain the track state, and generates a track defect emergency instruction based on the track state; The signal processing module receives the turnout state detection signal collected by the eddy current sensor, and exchanges information with the switch machine control module to obtain the turnout state indication signal, performs logic analysis on the turnout state detection signal and the turnout state indication signal based on the second analysis rule to obtain the turnout state, and generates a turnout abnormality emergency instruction based on the fork and knife state; The train is directed to the safe side in response to the track defect emergency instruction and / or the turnout abnormality emergency instruction and generates a track inspection report based on the track status and the turnout status.

9. A track detection system based on eddy current effect according to claim 8, characterized in that: The eddy current sensing device comprises a lifting mechanism, an eddy current probe, a fixing frame and a signal transmission line; the lifting mechanism comprises a lifting platform, a ball screw and a small motor; the signal transmission line is connected to the eddy current probe and is arranged in the fixing frame; The small motor is connected to the ball screw; the ball screw is arranged on a lifting platform and connected to the eddy current probe; a lifting thread is provided on the lifting platform, and when the eddy current probe passes through the track connection or generates excessive vibration, the small motor drives the ball screw to adjust the height of the ball screw through the lifting thread provided on the lifting platform to adjust the detection height of the eddy current probe.

10. A track detection system based on eddy current effect according to claim 9, characterized in that: The detection range of the eddy current sensing device is the depressions on both sides of the track.

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