CN108008210B - Broken rail detection method and device - Google Patents
Broken rail detection method and device Download PDFInfo
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- CN108008210B CN108008210B CN201710980531.5A CN201710980531A CN108008210B CN 108008210 B CN108008210 B CN 108008210B CN 201710980531 A CN201710980531 A CN 201710980531A CN 108008210 B CN108008210 B CN 108008210B
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- rail
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/005—Testing of electric installations on transport means
- G01R31/006—Testing of electric installations on transport means on road vehicles, e.g. automobiles or trucks
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61K—AUXILIARY EQUIPMENT SPECIALLY ADAPTED FOR RAILWAYS, NOT OTHERWISE PROVIDED FOR
- B61K9/00—Railway vehicle profile gauges; Detecting or indicating overheating of components; Apparatus on locomotives or cars to indicate bad track sections; General design of track recording vehicles
- B61K9/08—Measuring installations for surveying permanent way
Abstract
The application discloses a broken rail detection method and device. The method comprises the following steps: judging whether a first voltage is lower than a first voltage threshold value, wherein the first voltage is the voltage at the receiving device, and if the first voltage is larger than or equal to the first voltage threshold value, comparing whether the vector sum value of a first current and a second current meets a preset condition, and the first current and the second current are currents on a first steel rail and a second steel rail respectively; and if the vector sum value meets a preset condition, judging that the rail is broken. The method and the device provided by the embodiment of the application judge whether the rail breakage occurs or not through the sum of the current vectors on the two steel rails, and are not influenced by a transverse circuit, so that the judgment result is more accurate.
Description
Technical Field
The application belongs to the technical field of rail detection, and particularly relates to a rail breakage detection method and device.
Background
The broken rail is a rail constituting a current path necessary for a track circuit, and is broken by mechanical damage, stress accumulation, or the like, and is completely electrically disconnected. The rail break poses great threat to the train running safety and is a direct cause of multiple derailment accidents of the passenger-cargo train. Therefore, early warning and real-time inspection of rail breakage become essential monitoring contents.
At present, no matter an axis counting system, a satellite positioning system or communication positioning is adopted, the characteristic of whether a line is complete cannot be reflected in real time, and a track inspection vehicle inspects according to a specific period and does not have real-time performance. The track circuit utilizes the steel rail as a current path, and circuit structure changes, such as shunt, breakage and the like, occurring on the steel rail affect the receiving voltage of the receiver in real time.
At present, no matter a natural attenuation type or an electric isolation type non-insulation track circuit, the principle that voltage received by a track circuit receiver drops when a track is broken is utilized. As shown in fig. 1, before the rail is broken, the rail serves as a good conductor of electrical signals, which can effectively conduct signals sent by the transmitter to the receiver, when the rail is broken at a certain position, the current in the rail is interrupted, and the current sent by the transmitter can only reach the receiver by bypassing the point of the broken rail. Usually, the current can also flow to the receiver through a path of a steel rail-ballast resistor-earth-ballast resistor-steel rail, but compared with a steel rail serving as a good conductor, the impedance of the detour path is greatly increased, so that the current which can reach the receiver is greatly reduced after the rail is broken, and the receiving voltage drops.
As shown in fig. 2, in a traction power supply system in the prior art, an electric locomotive obtains electric energy from a contact network after raising a bow, and supplies the electric energy to a locomotive motor after reducing the voltage through a main transformer. The feeder line, the contact net, the steel rail and the return line form a double-conductor power supply system and form a closed loop through the electric locomotive. The current flowing in the traction power supply loop is traction current. Because of the electrical conduction between the rail and the ground, a portion of the traction current leaks into the ground through the rail after passing through the electric locomotive.
However, in order to ensure the personal safety of railway rails and track bed personnel, the rails are generally provided with grounding measures to reduce the voltage rise of the rails caused by traction current. This grounding is achieved by connecting the center point of the air coil or choke of the track circuit to a trackside ground, also called a transverse connection. The transverse connection has a significant effect on the track break check of the track circuit, since the signal current can continue to flow to the receiver through the path from the transmitting end through the transverse connection line via the trackside ground line to the receiving end. The current path caused by the lateral connection increases the rail break residual voltage of the receiver. In recent years, traction current in heavy-duty and high-speed railways is increasingly large, and in order to reduce rail voltage, the distance between two transverse connections needs to be reduced, and the reduction of the distance further compresses the rail break inspection allowance of the voltage drop rail break inspection technology.
To guarantee the broken rail inspection, the limitation and the problem are brought to the rail circuit, and the following problems exist at present:
in the interval, the transverse connection and grounding are conditions for ensuring the personal safety voltage of the rail surface, and meanwhile, an external circuitous loop of the steel rail is formed, so that the broken steel rail can not be inspected. In order to ensure the impedance of the external circuit, the arrangement distance of the external circuit must be limited.
In order to prevent the track circuit from losing a shunt by detouring loops outside the track circuit within the station, it is necessary to employ a single choke or disconnect a choke neutral connection line at a side return position. On a special line for a passenger, the connection mode causes unsmooth backflow to break down insulation, and when a wheel passes through the insulation section, a circuit is cut off to cause electric arcs to burn the insulation section and a rail head of a steel rail.
Disclosure of Invention
In order to overcome the technical problem, the embodiment of the invention discloses a rail breakage detection method and device.
In a first aspect, an embodiment of the present application provides a rail break detection device, including:
the grounding device is arranged between the two steel rails and is connected with the two steel rails;
the transmitting device is connected with the two steel rails and transmits signal current to the steel rails;
the receiving device is connected with the two steel rails and receives the signal current;
contact system for supplying electric energy to vehicles and generating traction current in rails
And the processor judges whether the rail break occurs or not through the vector sum of the current drawn by the two ends of the grounding device when the voltage at the receiving device is lower than the first voltage threshold value.
Optionally, the grounding device is an air core coil, and a central point of the air core coil is grounded.
Optionally, the sum of the currents is calculated by the processor.
Optionally, the sum of the currents is obtained from the ground current of the ground point of the grounding device.
Optionally, the device further comprises an alarm device, and when the rail break is judged, an alarm is given in real time.
On the other hand, an embodiment of the present application provides a rail break detection method, including:
determining whether a first voltage is below a first voltage threshold, the first voltage being a voltage at a receiving device;
if the first voltage is larger than or equal to a first voltage threshold value, comparing whether the vector sum value of a first traction current and a second traction current meets a preset condition, wherein the first traction current and the second traction current are traction currents on a first steel rail and a second steel rail respectively;
and if the vector sum value meets a preset condition, judging that the rail is broken.
Optionally, the predetermined condition is: the ratio of the difference in absolute values of the first and second traction currents to the absolute value of the sum of the first and second traction currents is greater than 0.5.
Optionally, if the first voltage is less than the first voltage threshold, a rail break alarm is issued.
Optionally, if the sum does not satisfy the predetermined condition, it is determined that the rail is in the adjustment state.
Optionally, after a predetermined time, if the first voltage is greater than the first voltage threshold, the alarm is stopped.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application.
FIG. 1 is a background diagram of an embodiment of the present application;
FIG. 2 is a schematic diagram of a traction power supply system in an embodiment of the present application;
FIG. 3 is a schematic view of a rail break detection apparatus without rail break according to an embodiment of the present application;
FIG. 4 is a schematic diagram of a rail break detection apparatus for rail break according to another embodiment of the present application
FIG. 5 is a partial schematic view of a rail break detection apparatus according to yet another embodiment of the present application;
fig. 6 is a schematic diagram of a rail break detection method according to another embodiment of the present application.
Detailed Description
In order to make the objects, features and advantages of the present invention more apparent and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
It will be understood by those within the art that the terms "first", "second", etc. in this application are used only to distinguish one device, module, parameter, etc., from another, and do not denote any particular technical meaning or necessary order therebetween.
Fig. 3 is a schematic diagram of a device for detecting rail break in the case of no rail break according to an embodiment of the present application, as shown in fig. 3, two rails 303,304 having a track bed resistance therebetween, the device includes a grounding device 306,307 arranged between the two rails 303,304, the grounding device may be an air coil, a center point of the air coil is a grounding point, a transmitting device 301 arranged between the rails and used for transmitting a signal current to the rails, and a receiving device 302 used for receiving the signal current transmitted by the transmitting device 301. The traction substation supplies power to the contact net, when the vehicle rises the bow, the electric energy is obtained through the contact net, so as to drive the vehicle to run,the feeder line, the contact net, the steel rail and the return line form a double-conductor power supply system, so that equidirectional symmetrical traction current I exists in the steel rail1And I2. Processor 305 passing current I1And I2Judging whether the rail is broken, if so, sending a rail breaking signal, and as shown in fig. 3, showing the situation of no rail breaking, in which two rails are in a symmetrical balance state to the traction current, that is, at the same position, the traction currents in the upper and lower rails are in the same direction. The processor 305 does not output the rail break signal at this time.
Fig. 4 is a schematic diagram of a device for detecting rail break in a rail break situation according to an embodiment of the present application, and as shown in fig. 4, when a track circuit is in a rail break state, the state of two rails is no longer symmetrical because a current path is cut off in one rail 303 at a rail break point and current is still normally conducted in the other rail 304. The current of the upper and lower rails is not equal in direction, and at the point of rail break, this characteristic is most obvious, because the current flowing in the rail where the rail break occurs is zero, while the current still flows in the other rail, if the unbalance degree is introduced to measure the unbalance degree of the two currents, it is defined as follows:
before rail break, the current of the upper and lower rails is in the same direction,
when the rail is broken, the unbalance degree is at the point of rail breaking
At other positions
Is a number between 0 and 100%.
In a grounding point, the imbalance of the steel rail is also reflected in the ground current of the grounding point.As shown in figure 5, in the balanced state, the current of the upper rail and the lower rail is symmetrical and in the same direction, and the grounding point grounding current is I according to kirchhoff's current lawN＝I1+I2＝2I1＝2I2；
After rail break, the rail is in unbalanced state, the current of upper and lower rails is no longer symmetrical, thus causing the change of ground point grounding current and leading wire current I1≠I2Earth current INJust like the sum of the upper and lower unbalance vectors of the two sides, at the moment, the unbalance expression of the grounding point position of the receiving end rail surface is as follows:
if the above 3 traction currents of the receiving end rail surface grounding point satisfy the following relations:
it can be judged that the rail is broken.
Of course, judging rail breakage
The threshold value can be set according to practical conditions or experience, for example, the rail is broken when the material of the rail changes or the temperature of the environment changes, and probably the beta is more than 40%.
An input of the processor 305, capable of inputting I1And I2Two currents, and due to IN＝|I1+I2I, so the input of the processor can also input I directlyN。
Fig. 6 is a method for detecting rail breakage according to an embodiment of the present application, as shown in fig. 6, including the following steps:
in one embodiment, the first voltage is a rail surface voltage at the receiving device, which drops when an abnormal condition occurs, and the first voltage threshold may be set based on empirical or experimental data, which may be different for different environments and different rail materials.
Step 602, if the first voltage is greater than or equal to a first voltage threshold, comparing whether the sum of the first current and the second current meets a predetermined condition;
generally, if the first voltage is equal to or greater than the first voltage threshold, the prior art would directly regard it as no rail break occurred, but due to the presence of the lateral circuit, such a situation may have occurred. Therefore, in one embodiment, if the first voltage is greater than or equal to the first voltage threshold, the comparison of the vector sum of the first traction current on the first rail and the second traction current on the second rail is continued to satisfy a preset condition, where the preset condition may be that the ratio of the vector difference between the first current and the second current to the vector sum of the first traction current and the second traction current is greater than 0.5:
of course this ratio can be set based on empirical or experimental data and the threshold can be different for different environments and different track materials.
In one embodiment, if the ratio of the vector difference to the vector sum satisfies a predetermined condition, for example, the ratio is greater than 0.5, it is determined that the rail is broken, and an alarm may be issued to warn that the rail is broken.
After step 602, if the sum does not satisfy the preset condition, determining that the steel rail is in a normal adjustment state; at the moment, the rail is judged not to be broken, the relay is sucked up, no alarm is given, and the step 601 is skipped to continue monitoring the rail.
After the step 601, a step 604 is further included, if the first voltage is lower than a first voltage threshold value, it is determined that an abnormal condition occurs in the steel rail, and an alarm is given;
in the embodiment of the invention, the rail is regarded as an abnormal condition, an alarm is temporarily sent out, and whether the abnormal condition occurs is further judged according to the subsequent conditions. The abnormal conditions are train occupation, cable disconnection, equipment failure or rail breakage.
Normally, if the abnormal condition disappears, the voltage at the receiving device returns to normal, the relay is sucked up, and the alarm is stopped. And if the first voltage is still lower than the first voltage threshold after the preset time, judging that the abnormal condition still exists, dropping the holding relay, and keeping the alarm.
Those of ordinary skill in the art will appreciate that the various illustrative elements and method steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.
The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to perform all or part of the steps of the method according to the embodiments of the present application.
Such computer-readable storage media include physical volatile and nonvolatile, removable and non-removable media implemented in any manner or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. The computer-readable storage medium specifically includes, but is not limited to, a USB flash drive, a removable hard drive, a Read-Only Memory (ROM), a Random Access Memory (RAM), an erasable programmable Read-Only Memory (EPROM), an electrically erasable programmable Read-Only Memory (EEPROM), flash Memory or other solid state Memory technology, a CD-ROM, a Digital Versatile Disk (DVD), an HD-DVD, a Blue-Ray or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. The above embodiments are only for illustrating the invention and are not to be construed as limiting the invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention, therefore, all equivalent technical solutions also belong to the scope of the invention, and the scope of the invention is defined by the claims.
Claims (7)
1. A broken rail detection device comprising:
the grounding device is arranged between the two steel rails and is connected with the two steel rails;
the transmitting device is connected with the two steel rails and transmits signal current to the steel rails;
the receiving device is connected with the two steel rails and receives the signal current;
contact system for supplying electric energy to vehicles and generating traction current in rails
A processor to determine whether a first voltage is below a first voltage threshold, the first voltage being a voltage at a receiving device;
when the voltage at the receiving device is lower than a first voltage threshold value, judging that the steel rail has an abnormal condition, giving an alarm, stopping the alarm if the first voltage is higher than or equal to the first voltage threshold value after a preset time, recovering the steel rail to be normal, and continuously judging whether the first voltage is lower than the first voltage threshold value;
when the voltage at the receiving device is larger than or equal to a first voltage threshold, judging whether rail breakage occurs or not through the vector sum of the traction currents at the two ends of the grounding device based on the existence of the transverse circuit; when the rail is broken, the unbalance degree is at the point of rail breaking
At other positions than the point of the rail break,
is a number between 0 and 100%; and after the rail is broken, the traction current of the grounding point of the receiving end rail surface of the grounding point meets the following requirements:
then it can be judged that the rail is broken, wherein I1And I2For symmetrical traction currents in the same direction in the rail, IN＝|I1+I2Degree of unbalance
The degree of imbalance of the two currents is measured.
2. A broken rail detecting device according to claim 1, wherein the grounding device is an air coil, and a center point of the air coil is grounded.
3. A rail break detection apparatus as claimed in claim 1, wherein said sum of currents is calculated by a processor.
4. A rail break detection device as claimed in claim 1, said sum of currents being derived from the ground current of the ground point of the grounding means.
5. A broken rail detecting device according to claim 1, further comprising an alarm device for giving an alarm in real time when a broken rail is judged.
6. A rail break detection method comprises the following steps:
the grounding device can be an air coil, the central point of the air coil is a grounding point, the transmitting device is arranged between the steel rails and is used for transmitting signal current to the steel rails, the receiving device is used for receiving the signal current transmitted by the transmitting device, and when a vehicle rises, electric energy is obtained through a contact net so as to drive the vehicle to run; wherein the content of the first and second substances,
determining whether a first voltage is below a first voltage threshold, the first voltage being a voltage at a receiving device; if the first voltage is greater than or equal to the first voltage threshold value, judging that the steel rail is in an abnormal condition; comparing whether the vector sum value of a first current and a second current meets a preset condition, wherein the first current and the second current are respectively traction currents on a first steel rail and a second steel rail;
if the vector sum value meets a preset condition, judging that the rail is broken;
the predetermined conditions are: the ratio of the difference in absolute value of the first and second traction currents to the absolute value of the sum of the first and second traction currents is greater than 0.5, i.e.:
wherein, I1And I2For symmetrical traction currents in the same direction in the rail, IN＝|I1+I2Degree of unbalance
Measuring the unbalance degree of the two currents;
if the first voltage is lower than the first voltage threshold value, judging that the steel rail is abnormal, and giving an alarm; after the preset time, if the first voltage is higher than or equal to the first voltage threshold value, the alarm is stopped, the steel rail returns to be normal, and whether the first voltage is lower than the first voltage threshold value or not is continuously judged.
7. The rail break detection method of claim 6, wherein if the sum does not satisfy a predetermined condition, it is determined that the rail is in the adjusted state.
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| CN201710980531.5A CN108008210B (en) | 2017-10-19 | 2017-10-19 | Broken rail detection method and device |
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| CN201710980531.5A CN108008210B (en) | 2017-10-19 | 2017-10-19 | Broken rail detection method and device |
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| CN108008210B true CN108008210B (en) | 2021-03-23 |
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| CN112068030B (en) * | 2020-09-27 | 2021-05-28 | 安徽江淮汽车集团股份有限公司 | Fault detection method, equipment, storage medium and device of grounding system |
| CN113125510A (en) * | 2021-04-21 | 2021-07-16 | 通号(北京)轨道工业集团有限公司轨道交通技术研究院 | Broken rail inspection method and system |
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| US4886226A (en) * | 1988-06-23 | 1989-12-12 | General Signal Corporation | Broken rail and/or broken rail joint bar detection |
| CN2543797Y (en) * | 2002-05-24 | 2003-04-09 | 北京全路通信信号研究设计院 | Rail track broken detector |
| CN1451577A (en) * | 2002-03-27 | 2003-10-29 | 阿尔斯托姆比利时股份有限公司 | Method and apparatus for testing rail break |
| CN101954915A (en) * | 2009-11-25 | 2011-01-26 | 兰州交通大学 | Broken rail real-time detection device and detection method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105984475B (en) * | 2015-02-02 | 2019-06-11 | 兰州恒通轨道交通设备有限公司 | A kind of novel broken rail monitoring system |
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| US4886226A (en) * | 1988-06-23 | 1989-12-12 | General Signal Corporation | Broken rail and/or broken rail joint bar detection |
| CN1451577A (en) * | 2002-03-27 | 2003-10-29 | 阿尔斯托姆比利时股份有限公司 | Method and apparatus for testing rail break |
| CN2543797Y (en) * | 2002-05-24 | 2003-04-09 | 北京全路通信信号研究设计院 | Rail track broken detector |
| CN101954915A (en) * | 2009-11-25 | 2011-01-26 | 兰州交通大学 | Broken rail real-time detection device and detection method thereof |
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