Subway line stray current monitoring method based on internet of things and data mining technology

Abstract

The application discloses a subway line stray current monitoring method based on an internet of things and a data mining technology, relates to the field of rail transit, and comprises a monitoring system which is composed of station test terminals, section yard throat area test terminals, in-warehouse test terminals, surrounding soil surface potential test terminals and buried metal structure test terminals which are arranged in different areas respectively. The application can perform big data mining on stray current related parameters by using a special algorithm through an internet of things cloud, can evaluate the severity of stray current of the whole line, can find line operation safety hidden dangers, can improve the safety level of line operation, can provide auxiliary decision for operation personnel, does not operate on existing primary equipment, does not additionally increase power distribution cabinet bodies, and integrates power supply modules, transmission modules, acquisition modules and high-precision voltage sensors in airtight small box bodies in the terminal, so that the terminal can be directly placed in an OVPD cabinet or a single guide cabinet, space and cost are saved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rail transit, more particularly, the present application relates to a metro line stray current monitoring method based on internet of things and data mining technology. BACKGROUND

[0002] Urban rail transit generally adopts direct current power supply, usually taking the steel rail as the traction current return path to send the current back to the negative pole of the rectifier unit, and the steel rail is fixed on the track bed through the insulating pad and fastener, which cannot be completely insulated from the ground, resulting in the flow of traction return current in the steel rail into the ground, so that the potential between the steel rail and the ground is generated, that is, the steel rail potential. The excessively high steel rail potential will threaten the personal safety of passengers, and will also cause the frequent action of the steel rail potential limiter (OVPD), aggravating the current leakage from the steel rail to the underground, forming stray current. Meanwhile, the section yard is often a weak link of the steel rail insulation, and the stray current condition is more serious. The stray current will cause electrochemical corrosion to the tunnel structure steel rail and other underground metal structures, which may cause serious consequences in the long run.

[0003] The steel rail potential between the main line and the section yard is affected by the throat area conduction device and the section yard grounding mode. The process of the throat area conduction device and the train crossing the throat area insulation joint will cause the mutual influence of the steel rail potential between the main line and the section yard. From the perspective of the safety of maintenance personnel, the setting value of the section yard steel rail potential limiter is lower than that of the main line steel rail potential limiter, such as 60V for a section. The steel rail potential of the main line enters the section yard, causing the section yard steel rail potential limiter to ground. On the one hand, it aggravates the stray current, and on the other hand, it makes the system work in a single-ended grounding condition, which worsens the main line steel rail potential. In view of the above situation, it is very necessary to design a metro line stray current monitoring method. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present application provide a metro line stray current monitoring method based on internet of things and data mining technology. The related parameters of the monitored stray current are subjected to big data mining, and the severity of the whole line stray current is evaluated, so as to solve the problems raised in the above background technology.

[0005] In order to achieve the above object, the present application provides the following technical scheme: a subway line stray current monitoring method based on Internet of Things and data mining technology, comprising a monitoring system composed of station test terminals, section yard throat area test terminals, in-warehouse test terminals, surrounding soil surface potential test terminals and buried metal structure test terminals arranged in different areas respectively, the station test terminals, the section yard throat area test terminals, the in-warehouse test terminals, the surrounding soil surface potential test terminals and the buried metal structure test terminals are intelligently controlled through the Internet of Things cloud, and the station test terminals, the section yard throat area test terminals, the in-warehouse test terminals, the surrounding soil surface potential test terminals and the buried metal structure test terminals are each composed of a power supply module, a transmission module, an acquisition module and a high-precision sensor, and are synchronously time-granted through a mobile network, wherein the high-precision sensor comprises a high-precision voltage sensor and a high-precision current sensor.

[0006] As a further improvement of the technical scheme of the present application, the acquisition module is connected with the high-precision sensor through a cable for collecting data of the monitoring points.

[0007] As a further improvement of the technical scheme of the present application, the transmission module is connected with the acquisition module through a communication cable for receiving data and uploading the data to the Internet of Things cloud in real time through a mobile network.

[0008] As a further improvement of the technical scheme of the present application, the real-time and single-day earth current injected into the whole line is calculated in the Internet of Things cloud, and the specific calculation method is as follows:

[0009] (1). The earth charge Q injected into the whole line at the tth second s (t), unit A·s,

[0010]

[0011] In the above formula, n is the total number of stations in the whole line, Ii(t) is the earth current (or earth return current) injected by the OVPD of the ith station at the tth second, m is the total number of section yards in the whole line, Ij(t) is the earth current (or earth return current) injected by the OVPD in the jth section yard at the tth second. j

[0012] (2). The earth charge Q injected into the whole line in a single day d , unit A·s,

[0013]

[0014] In the above formula, k is the total number of monitoring seconds in a single day, Q(t) is the earth charge injected into the whole line at the tth second in a single day. s

[0015] ​​As a further improvement of the technical scheme of the present application, the station test terminal or the in-yard test terminal is placed in a rail potential limiter cabinet, the positive pole of the high-precision voltage sensor is connected with the rail end, and the negative pole is connected with the ground end, for monitoring the rail potential; the high-precision current sensor is connected in the ground branch in the rail potential limiter, for monitoring the current flowing to the ground when the rail potential limiter is closed.

[0016] As a further improvement of the technical scheme of the present application, the segment yard throat area test terminal is installed in the cabinet of the uplink and downlink unidirectional conduction device, the positive pole of the high-precision voltage sensor is connected with the positive line rail, and the negative pole is connected with the segment yard rail, for monitoring the potential difference between the positive line rail and the segment yard rail; the high-precision current sensor is connected in the branch connected with the segment yard rail of the unidirectional conduction device, for monitoring the current when the unidirectional conduction device is conducted.

[0017] As a further improvement of the technical scheme of the present application, the surrounding soil surface potential test terminal is placed near the segment yard, the high-precision voltage sensor is connected with four reference electrodes near the segment yard, for monitoring the ground potential near the segment yard.

[0018] As a further improvement of the technical scheme of the present application, the buried metal structure test terminal is placed near the test pile, the positive pole of the high-precision voltage sensor is connected with the terminal of the buried metal structure, and the negative pole is connected with the distant buried reference electrode, for monitoring the polarization potential of the buried metal structure.

[0019] The present application has the following beneficial effects:

[0020] Compared with the prior art, the present application can perform big data mining on the stray current related parameters through the Internet of Things cloud using a special algorithm, evaluate the severity of the stray current on the whole line, find the line operation safety hazards, improve the safety level of line operation, provide auxiliary decision for the operation personnel, do not operate the existing primary equipment, do not additionally increase the power distribution cabinet body, and integrate the power supply module, the transmission module, the acquisition module and the high-precision voltage sensor in a closed small box body, which can be directly placed in the OVPD cabinet or the single guide cabinet, thereby saving space and cost, and the whole line terminals are synchronized by the mobile network, the high-precision sensor continuously measures the voltage and current data, and the data completeness, synchronization and accuracy are ensured; the Internet of Things cloud receives the real-time data of the whole line terminals in parallel, and ensures that all data can be transmitted in real time. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The figure is a system schematic diagram of the present application.

[0022] Figure 2 The figure is a circuit connection schematic diagram of the station test terminal in the present application.

[0023] Figure 3This is a schematic diagram of the circuit connection of the mid-field pharyngeal region testing terminal of the present invention.

[0024] Figure 4 This is a schematic diagram of the circuit connection of the surrounding soil surface potential testing terminal in this invention.

[0025] Figure 5 This is a schematic diagram of the circuit connection of the buried metal structure testing terminal in this invention. Detailed Implementation

[0026] 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 some embodiments of the present invention, and not all embodiments. 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.

[0027] like Figure 1 As shown, the stray current monitoring method for subway lines based on IoT and data mining technology includes a monitoring system. The monitoring system consists of station test terminals, depot throat area test terminals, depot test terminals, surrounding soil surface potential test terminals, and buried metal structure test terminals set up in different areas. All test terminals are intelligently controlled via the IoT cloud. Each of these terminals contains a power supply module, a transmission module, a data acquisition module, and high-precision sensors, and is synchronized via a mobile network. The high-precision sensors include high-precision voltage sensors and high-precision current sensors.

[0028] like Figure 2 As shown, in the station test terminal or the in-depot test terminal, high-precision voltage and current sensors measure the rail-to-ground voltage and the current flowing to the ground when the OVPD is closed, respectively. The acquisition module is connected to the sensors via a cable, acquiring two potential data points and two current data points per second. The transmission module is connected to the sampling module via a communication cable to receive data. The transmission module uses a SIM card to connect to the IoT cloud via a mobile network, uploading information such as the station (depot) information, time, and collected data. The IoT cloud calculates the real-time and daily injected ground current for the entire line. The specific calculation method is as follows:

[0029] (1). The amount of charge Q injected into the ground at second t along the entire line. s (t), in units of A·s,

[0030]

[0031] In the above formula, n is the total number of stations, Ii(t) is the injected current (or ground return current) of the OVPD at the i-th station at the t-th second, m is the total number of section yards, Ij(t) is the injected current (or ground return current) of the OVPD at the j-th section yard at the t-th second, and Q is the total injected current (or ground return current) of the OVPD in a single day. j In the above formula, n is the total number of stations, Ii(t) is the injected current (or ground return current) of the OVPD at the i-th station at the t-th second, m is the total number of section yards, Ij(t) is the injected current (or ground return current) of the OVPD at the j-th section yard at the t-th second, and Q is the total injected current (or ground return current) of the OVPD in a single day.

[0032] (2). The total injected charge Q of the OVPD in a single day d , unit: A·s,

[0033]

[0034] In the above formula, k is the total number of seconds in a single day, Q is the total injected charge of the OVPD in a single day, and Q(t) is the injected charge of the OVPD at the t-th second in a single day. s In the above formula, k is the total number of seconds in a single day, Q is the total injected charge of the OVPD in a single day, and Q(t) is the injected charge of the OVPD at the t-th second in a single day.

[0035] As shown in FIG. 1, the test terminal in the throat area of the section yard is connected with high-precision voltage and current sensors, which measure the potential difference between the main line and the section yard rail in the one-way conduction device and the current when the device is turned on. The collection module is connected with the sensors through a cable and collects two potential data and two current data per second. The transmission module is connected with the sampling module through a communication cable and is used to receive data. The transmission module uses a SIM card to connect with the Internet of Things cloud through a mobile network, uploads the information of the section yard, time, and collected data, etc. Figure 3 As shown in FIG. 2, the surrounding soil surface potential test terminal is connected with high-precision voltage sensors and four saturated copper sulfate reference electrodes buried in the surrounding soil of the section yard. The a and b electrodes are connected in parallel with the section yard rail, and the wire length is twenty meters. The c and d electrodes are perpendicular to the a and b electrodes and are connected with a wire length of twenty meters. The collection module is connected with the sensors through a cable and collects two potential data per second at each electrode. The transmission module is connected with the sampling module through a communication cable and is used to receive data. The transmission module uses a SIM card to connect with the Internet of Things cloud through a mobile network, uploads the information of the location, date, and collected data, etc.

[0036] Figure 4 As shown in FIG. 3, the buried metal structure test terminal is connected with high-precision voltage sensors, buried metal terminals, and reference electrodes. The sensors measure the polarization potential of the buried metal. The collection module is connected with the sensors through a cable and collects two potential data per second at each electrode. The transmission module is connected with the sampling module through a communication cable and is used to receive data. The transmission module uses a SIM card to connect with the Internet of Things cloud through a mobile network, uploads the information of the section yard, date, and collected data, etc.

[0037] As shown in FIG. 3, the buried metal structure test terminal is connected with high-precision voltage sensors, buried metal terminals, and reference electrodes. The sensors measure the polarization potential of the buried metal. The collection module is connected with the sensors through a cable and collects two potential data per second at each electrode. The transmission module is connected with the sampling module through a communication cable and is used to receive data. The transmission module uses a SIM card to connect with the Internet of Things cloud through a mobile network, uploads the information of the section yard, date, and collected data, etc. Figure 5

[0038] ​​The station test terminal, section throat area test terminal, in-warehouse test terminal, surrounding soil surface potential test terminal and buried metal structure test terminal are all synchronized with time through a mobile network and monitor the stray current related parameters for 24 hours without interruption.

[0039] To sum up, the application can use a special algorithm to mine the big data of the stray current related parameters through the Internet of Things cloud, evaluate the severity of the stray current on the whole line, find the hidden danger of line operation safety, and improve the safety level of line operation. The power supply module, transmission module, acquisition module and high-precision voltage sensor in the terminal are integrated in a sealed small box, which can be directly placed in the OVPD cabinet or single guide cabinet, saving space and cost. The whole line terminal is synchronized with time through a mobile network, and the high-precision sensor measures voltage and current data without interruption, ensuring the completeness, synchronicity and accuracy of the data. The Internet of Things cloud receives real-time data from the whole line terminal in parallel, ensuring that all data can be transmitted in real time.

[0040] The above only describes the preferred embodiments of the application and is not intended to limit the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1.A metro line stray current monitoring method based on Internet of Things and data mining technology, which is realized by a monitoring system, and is characterized in that: The monitoring system is composed of station test terminals, section yard throat area test terminals, in-warehouse test terminals, surrounding soil surface potential test terminals and buried metal structure test terminals arranged in different areas respectively, the station test terminals, section yard throat area test terminals, in-warehouse test terminals, surrounding soil surface potential test terminals and buried metal structure test terminals are intelligently controlled through the Internet of Things cloud, and the station test terminals, section yard throat area test terminals, in-warehouse test terminals, surrounding soil surface potential test terminals and buried metal structure test terminals are all composed of power supply modules, transmission modules, acquisition modules and high-precision sensors, and are synchronously time-granted through mobile networks, wherein the high-precision sensors include high-precision voltage sensors and high-precision current sensors arranged therein; The station test terminal or the in-warehouse test terminal is placed in a rail potential limiter cabinet, the positive electrode of the high-precision voltage sensor is connected with the rail end, and the negative electrode is connected with the ground end, for monitoring the rail potential; the high-precision current sensor is connected in the ground branch in the rail potential limiter, for monitoring the current flowing to the ground when it is closed; The section yard throat area test terminal is installed in the cabinet of the uplink and downlink unidirectional conduction device, the positive electrode of the high-precision voltage sensor is connected with the positive line rail, and the negative electrode is connected with the section yard rail, for monitoring the potential difference between the positive line rail and the section yard rail; the high-precision current sensor is connected in the branch connected with the section yard rail of the unidirectional conduction device, for monitoring the current when it is conducted. 2.The subway line stray current monitoring method based on the Internet of Things and data mining technology according to claim 1, characterized in that: The acquisition module is connected with the high-precision sensor through a cable, for collecting data of the monitoring points. 3.The subway line stray current monitoring method based on the Internet of Things and data mining technology according to claim 1, characterized in that: The transmission module is connected with the acquisition module through a communication cable, for receiving data and uploading the data to the Internet of Things cloud in real time through a mobile network. 4.The subway line stray current monitoring method based on the Internet of Things and data mining technology according to claim 1, characterized in that: The Internet of Things cloud calculates the real-time and single-day injected ground current of the whole line, and the specific calculation method is as follows: (1). The total line of the t second injection of the earth charge Q s (t), units of A·s, In the above formula, n is the total number of stations on the line, I i (t) is the i-th station OVPD injected into the ground current or ground return at the t-th second, m is the total number of fields on the line, I j (t) is the j-th field OVPD injected into the ground current or ground return at the t-th second. (2). The total daily injection of the earth's electric charge Q d , unit A·s, In the above formula, k is the total number of seconds of a single day, Q s (t) is the injected charge amount into the ground at the tth second of the entire line for a single day. 5.The subway line stray current monitoring method based on the Internet of Things and data mining technology according to claim 1, characterized in that: The surrounding soil surface potential test terminal is placed near the section yard, the high-precision voltage sensor is connected with four reference electrodes near the section yard, for monitoring the ground potential near the section yard. 6.The subway line stray current monitoring method based on the Internet of Things and data mining technology according to claim 1, characterized in that: The buried metal structure test terminal is placed near the test pile, the positive electrode of the high-precision voltage sensor is connected with the terminal of the buried metal structure, and the negative electrode is connected with a reference electrode far away, for monitoring the polarization potential of the buried metal structure.

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