Track circuit compensation capacitor and track circuit

Abstract

The utility model belongs to the technical field of track circuits, and particularly relates to a track circuit compensation capacitor and a track circuit, two ends of the compensation capacitor are respectively connected on two steel rails of a track, and the compensation capacitor is composed of two cores which are connected in series. The track circuit compensation capacitor provided by the utility model adopts two cores connected in series, so that the voltage withstanding performance of the compensation capacitor is improved, the probability of short circuit fault of the whole compensation capacitor is effectively reduced, and the reliability of a track circuit system is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the track circuit technical field, concretely relates to a track circuit compensation capacitor and track circuit. BACKGROUND

[0002] The statements in this section merely provide background information related to the utility model and do not necessarily constitute prior art.

[0003] The compensation capacitor (i.e. track circuit compensation capacitor) for railway signal is used for compensating the steel rail inductance, improving the "signal to interference ratio" and transmission length of track circuit, realizing the inspection of steel rail breakage and improving the short-circuit current of locomotive signal at the entry end of track circuit.

[0004] The working principle of compensation capacitor is to regard each compensation section steel rail L and capacitor C as "series resonance", as shown in the figure. Figure 1 In this way, a resistance load R is obtained at the entry end (A, A') of the compensation section, and a higher output level is obtained at the exit end (C, C'). When the ballast resistance changes from the minimum to infinity, the characteristic impedance value of track circuit changes little, and the output level is stable. When the compensation capacitor fails, the receiving voltage of track circuit receiver will decrease, and when multiple compensation capacitors in the same section fail simultaneously, the corresponding track relay of the section may drop, causing a "red light band" fault and affecting the transportation efficiency.

[0005] The internal structure of the existing railway signal compensation capacitor is single core, and the failure rate gradually increases with the increase of service time when the compensation capacitor is used in the field. The common failure modes are capacity value decrease, appearance change and lead wire breakage. The failure mechanisms mainly include three categories: open circuit, short circuit and poor contact. Since the existing compensation capacitor is single core, when the capacitor is short-circuited, it will directly cause track short-circuit "red light band", affect the transmission of frequency shift signal, and it is difficult to locate the fault after the capacitor fails, which affects a long time and a large range. When the capacitor in a certain place of the track section is open-circuited, it is equivalent to losing the compensation effect, which will cause the decrease of receiving voltage, but the open circuit of single capacitor lead wire will not cause "red light band". The contact failure of capacitor in track circuit will cause the fluctuation of receiving voltage, which will not cause "red light band". As can be seen, the influence of short-circuit fault on track circuit is greater than that of open circuit and poor contact. Therefore, it is necessary to develop a compensation capacitor to reduce the probability of internal short circuit of compensation capacitor and reduce the influence on track circuit. SUMMARY

[0006] In order to overcome the defects in the background art, the utility model provides a track circuit compensation capacitor and track circuit, the track circuit compensation capacitor is double core in series, the withstand voltage performance of compensation capacitor is improved, the probability of short circuit fault of compensation capacitor as a whole is effectively reduced, and the reliability of track circuit system is improved.

[0007] The utility model discloses the technical scheme adopted is: a track circuit compensation capacitor, both ends of the compensation capacitor are connected on two rails of track respectively, and the compensation capacitor is double core in series.

[0008] Further,

[0009] The compensation capacitor includes a first core and a second core.

[0010] The first core and the second core are in series, and one side of the first core away from the second core and one side of the second core away from the first core are connected with a lead wire.

[0011] Further,

[0012] The first core and the second core are in series through copper foil welding.

[0013] One end face of the first core and the second core is provided with a gold spraying layer, and the gold spraying layer is connected with one end of the lead wire through welding.

[0014] Further,

[0015] The other end of the lead wire is provided with a peg head or a copper terminal, and the lead wire is connected on the rail of the track through the peg head or the copper terminal.

[0016] Further,

[0017] Further comprising a metal shell.

[0018] The first core and the second core are arranged in the metal shell.

[0019] Further,

[0020] Further comprising a plastic shell.

[0021] The plastic shell is wrapped outside the metal shell.

[0022] The first core and the second core and the metal shell, and the metal shell and the plastic shell are filled with epoxy resin potting.

[0023] Further,

[0024] Further comprising a monitoring module for monitoring the state of the compensation capacitor.

[0025] The monitoring module is arranged outside the compensation capacitor.

[0026] The monitoring module includes a current sensor and an acquisition processing unit.

[0027] The current sensor is used for monitoring the current flowing through the compensation capacitor.

[0028] The acquisition processing unit is used for processing and analyzing the current signal monitored by the current sensor and giving positioning early warning and alarm information.

[0029] Further,

[0030] The compensation capacitor has a unique device address;

[0031] The acquisition processing unit comprises an acquisition submodule, a communication submodule, an external server and a track circuit diagnosis system;

[0032] The acquisition submodule is used for acquiring detection data of the current sensor, and the detection data is sent to the external server through the communication submodule;

[0033] The external server uploads the detection data to the track circuit diagnosis system after operation and processing;

[0034] The track circuit diagnosis system analyzes the uploaded data and gives positioning early warning and alarm information according to the device address of the compensation capacitor.

[0035] Based on the same inventive concept, the utility model also provides a track circuit, the track circuit includes the track circuit compensation capacitor as described above.

[0036] Compared with the prior art, the utility model has the beneficial effects that:

[0037] 1. Structural innovation, a new core is connected in series to form a double-core series compensation capacitor, which effectively improves the withstand voltage performance of the compensation capacitor, greatly reduces the probability of overall short circuit failure of the compensation capacitor, and improves the reliability of the track circuit system;

[0038] 2. The two capacitor cores are connected in series by copper foil welding, which is convenient for construction and reliable in connection, and can well meet the quality requirements of double-core series connection;

[0039] 3. The track circuit compensation capacitor further comprises a monitoring module for monitoring the state of the compensation capacitor, which can well monitor the state of the compensation capacitor by adding the monitoring module, can timely detect capacitor failure and locate the compensation capacitor with failure, can guide the on-site personnel to timely handle the failure, can further prevent the occurrence of overall short circuit of the compensation capacitor, and thus better improves the reliability of the track circuit system.

[0040] Other features and advantages of the utility model will be described in the subsequent description, and some of them will become apparent from the description, or will be understood by implementing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structure indicated in the description, claims and drawings.

[0041] The present invention will be further described below with reference to the accompanying drawings. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram illustrating the working principle of a compensation capacitor in the prior art.

[0044] Figure 2 This is a schematic diagram of the structure of a compensation capacitor with a dual-core series structure according to an embodiment of the present invention;

[0045] Figure 3 for Figure 2 The diagram shows the working principle of the compensation capacitor.

[0046] Figure 4 This is a schematic diagram illustrating the simulation analysis of a single-core short circuit in a compensation capacitor according to an embodiment of this utility model.

[0047] Figure 5 This is a schematic diagram of the copper foil welding structure between two cores in a compensation capacitor according to an embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of a compensation capacitor monitoring module according to an embodiment of the present invention and its working principle.

[0049] The markings in the diagram are: 1-compensation capacitor, 2-plug head, 3-lead wire, 4-plastic shell, 5-first core, 6-second core, 7-epoxy resin, 8-metal shell, 9-lead wire, 10-solder, 11-copper foil, 12-acquisition section, 13-transmission cable, 14-current sensor, 15-server, 16-diagnostic system. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0051] like Figures 2 to 6As shown, the embodiment discloses a track circuit compensation capacitor 1, two ends of the compensation capacitor 1 are connected to two rails of the track respectively, and the compensation capacitor 1 is a double-core in series.

[0052] The track circuit compensation capacitor 1 in the technical scheme has a double-core in series, that is, a double-core in series structure is adopted, so that the withstand voltage performance of the compensation capacitor 1 is improved, the probability of short circuit failure of the compensation capacitor 1 as a whole is effectively reduced, and the reliability of the track circuit system is improved.

[0053] In the embodiment, the double-core in series structure includes two series-connected capacitor cores, and the capacitor core is a thin film capacitor. For the thin film capacitor, the greater the capacitance value is, the larger the core size is, and when a plurality of cores are connected in series (1 / C = 1 / C1 + 1 / C2 + … + 1 / Cn), the total capacitance value is smaller than that of a single core. Therefore, if a compensation capacitor 1 with a certain capacitance value is required, two or more cores with larger capacitance values (and larger sizes) need to be connected in series, so that the volume of the compensation capacitor 1 as a whole is increased, the amount of raw materials, the process cost and the installation space on site are all increased. Therefore, from the production process and the installation requirements on site, the compensation capacitor 1 preferably adopts a structure of two cores in series, that is, a double-core in series structure.

[0054] The embodiment of the utility model provides a compensation capacitor 1 of double-core in series structure, that is, the compensation capacitor 1 is internally provided with a structure of two capacitor cores C1, C2 (C1', C2') in series, as shown in Figure 3 .

[0055] When the two cores C1, C2 in the compensation capacitor 1 are connected in series, the capacitance is reduced, and the withstand voltage value is increased. When a lightning surge or a large traction current occurs on site, because the withstand voltage of the series-connected cores is high, the probability of breakdown and short circuit of the compensation capacitor 1 as a whole is reduced. Assuming that one of the cores is short-circuited, at this time, the other core is still working, through simulation analysis (such as Figure 4 ), when the single core in the compensation capacitor 1 is short-circuited and the other core is normally working, only the received voltage of the track circuit is reduced, and the "red light band" is not caused.

[0056] Figure 4In the example, the carrier frequency is 1700 Hz, the section length is 971 m, the ballast resistance is 1 Ω·km, the number of compensation capacitors is 16, the compensation capacitor value is 25 μF (i.e., the nominal value of the capacitor is 25 μF), the nominal value of each of the two cores of the compensation capacitor 1 in the double-core series structure is 50 μF, and when one of the cores is short-circuited, the value of the compensation capacitor 1 rises to 50 μF, the compensation effect is weakened, the overall bias of the transmission channel is increased, the frequency shift signal is attenuated to a certain extent on the rail, the voltage at the receiving end is reduced but is still higher than the track relay pickup threshold, and the track circuit can work normally. Therefore, the compensation capacitor 1 in the double-core series structure can improve the voltage resistance performance, reduce the failure rate of the track circuit system, and improve the system reliability.

[0057] Further, the compensation capacitor 1 includes two capacitor cores, i.e., a first core 5 and a second core 6, the first core 5 is connected in series with the second core 6, and one end of each of the first core 5 and the second core 6 is connected with a lead wire 3. The first core 5 and the second core 6 can be connected through internal lead wires 9 (one or more) or can be connected through a plate. The compensation capacitor formed by the two capacitor cores in series is used to compensate the rail inductance, so that the track circuit characteristic presents a pure resistance, and the stable transmission of the frequency shift signal is ensured. The internal structure of the compensation capacitor 1 is a double-core series structure, and one lead wire 3 is arranged at each end of the compensation capacitor 1, so that the two ends of the compensation capacitor 1 can be connected to the two rails of the track, respectively.

[0058] In some embodiments, the first core 5 and the second core 6 are connected in series through copper foil welding, and a gold-plated layer is arranged on one end face of each of the first core 5 and the second core 6, and the gold-plated layer is connected with one end of the lead wire 3 through welding. In this embodiment, the two cores are connected through internal lead wires 9, and the series connection is directly achieved by copper foil welding in actual implementation. After the metal layer (i.e., the gold-plated layer) is plated on the end face of the capacitor core, the lead wire 3 is welded to the capacitor core.

[0059] In some embodiments, a peg head 2 or a copper terminal is arranged at one end of the lead wire 3 away from the capacitor core, and the lead wire 3 is connected to the rail of the track through the peg head 2 or the copper terminal. In this embodiment, the peg head 2 or the copper terminal is connected with the lead wire 3 through crimping, and the peg head 2 or the copper terminal is used to connect the compensation capacitor 1 to the rail. The example in the diagram of this embodiment shows that the peg head 2 is arranged at one end of the capacitor core.

[0060] In some embodiments, the track circuit compensation capacitor 1 further comprises a metal shell 8 and a plastic shell 4, the first core 5 and the second core 6 are arranged inside the metal shell 8, the metal shell 8 is wrapped with the plastic shell 4, and the first core 5 and the second core 6 and the metal shell 8 and the plastic shell 4 are filled with epoxy resin 7 for encapsulation. In this embodiment, the double-core is wrapped with a metal shell 8 and a plastic shell 4, and the gap between the core and the metal shell 8 and the gap between the plastic shell 4 and the metal shell 8 are filled with epoxy resin 7 for encapsulation to achieve the sealing protection of the compensation capacitor 1.

[0061] The working principle of the compensation capacitor 1 with double-core series structure in this embodiment is shown in Figure 3 When a short circuit fault occurs in the core C1 inside the compensation capacitor 1 due to lightning surge, large traction current, etc., the core C2 can still work normally, the overall capacitance value rises, the compensation effect weakens, the steel rail as a whole becomes inductive, the frequency shift signal is attenuated to a certain extent on the steel rail, and the receiving end voltage is reduced. Through simulation analysis, when a single capacitor core is short-circuited and the capacitance value rises, the receiving end voltage is still higher than the track relay pickup threshold, and the track circuit can work normally. Therefore, the advantage of the double-core compensation capacitor 1 over the single-core compensation capacitor is that the overall withstand voltage performance of the capacitor is improved, the probability of internal short circuit fault of the capacitor is reduced, and the reliability of the track circuit system is improved.

[0062] The capacitor core in this embodiment adopts a film capacitor, and the withstand voltage level of the capacitor can also be improved by increasing the sheet resistance of the metallized film or increasing the thickness of the dielectric film, but the improvement degree of the withstand voltage value is not as good as the direct series connection of two cores. When two capacitors are connected in series, the overall withstand voltage value is the sum of the withstand voltage values of the two capacitors.

[0063] As known from the foregoing, for the track circuit compensation capacitor 1 with two cores connected in series in this embodiment, when a short circuit fault occurs in one of the two series-connected cores, the other core can still work, and the entire compensation capacitor can still work, although the receiving end voltage of the track circuit is reduced, but the receiving end voltage value will not be below the threshold value, and the track circuit system can still work normally, so in practice the compensation capacitor 1 is generally continued to be used. However, in the case of continuing to use the compensation capacitor 1, it cannot be ruled out that the other core may also be short-circuited, and when both cores are short-circuited, i.e. the entire compensation capacitor 1 is short-circuited, it is equivalent to train shunting, which will cause the track circuit to be "red light band", causing the train to stop, and the fault is directed to the safe side.

[0064] In order to further prevent the occurrence of the overall short circuit of the compensation capacitor 1, the track circuit compensation capacitor 1 of the embodiment of the utility model further includes a monitoring module for monitoring the state of the compensation capacitor 1, and the state of the compensation capacitor 1 can be well monitored by adding the monitoring module, the compensation capacitor 1 can detect the capacitor fault in time and locate the fault, so that the on-site personnel can be guided to handle the fault in time. The monitoring module is arranged outside the compensation capacitor 1, the monitoring module includes a current sensor 14 and an acquisition processing unit, the current sensor 14 is used for monitoring the current flowing through the compensation capacitor 1, and the acquisition processing unit is used for processing and analyzing the current signal monitored by the current sensor 14 and giving positioning early warning and alarm information. The monitoring module of the embodiment is composed of the current sensor 14 and the acquisition processing unit, the current sensor 14 is essentially an induction coil, and the change of the current on the lead wire 3 of the compensation capacitor 1 is sensed through the electromagnetic induction principle. As shown in FIG. Figure 6 The acquisition processing unit includes an acquisition part 12 in the embodiment, the current sensor 14 is connected with the acquisition part 12 through a transmission cable 13 (the acquisition part 12 includes an acquisition submodule and a communication submodule, and also includes a power supply submodule in the embodiment), the current sensor 14 is sleeved on the lead wire 3 of the compensation capacitor 1 to monitor the current flowing through the capacitor in real time, the current curve changes when one of the cores is short-circuited, and then the deterioration of the state of the compensation capacitor 1 can be found in time.

[0065] Further, the compensation capacitor 1 has a unique device address, the acquisition processing unit includes an acquisition submodule, a communication submodule, an external server 15 and a track circuit diagnosis system 16, the acquisition submodule is used for acquiring the detection data of the current sensor 14, the detection data is sent to the external server 15 through the communication submodule, the detection data is uploaded to the track circuit diagnosis system 16 after being operated and processed by the external server 15, the uploaded data is analyzed by the track circuit diagnosis system 16 and positioning early warning and alarm information are given according to the device address of the compensation capacitor 1. In the track circuit system, each compensation capacitor 1 corresponds to a unique device address, and the fault location is performed according to the device address after the capacitor deteriorates, and positioning early warning and alarm information are given. In the embodiment, the acquisition submodule is used for acquiring the current detected by the current sensor 14, the acquisition function of the current is realized; the communication submodule is composed of an Internet of Things chip and an antenna, and the data transmission function is realized; the power supply submodule is composed of a power supply board and a battery, and the power supply function of the entire acquisition part 12 is realized. As shown in FIG. Figure 6As shown, in actual implementation, the collected data is sent to an external server 15 through a base station, the external server 15 in this embodiment is a server (DTU), the server 15 performs operation processing on the data and uploads to a track circuit diagnosis system 16, the diagnosis system 16 can analyze the uploaded data and give early warning, alarm information and the like to guide the on-site personnel to timely handle the fault. The monitoring module and the monitoring of the state of the compensation capacitor 1 can further refer to CN110988585A (online diagnosis device and method for compensation capacitor fault based on Internet of Things) or the prior art, which will not be described here.

[0066] In summary, the track circuit compensation capacitor 1 with the double-core sub-series structure not only improves the voltage resistance performance of the compensation capacitor 1, effectively reduces the probability of overall short circuit failure of the compensation capacitor 1, but also has a certain buffering effect, facilitates timely replacement of a double-core sub-series compensation capacitor 1 with a short-circuited core, further effectively prevents the overall short circuit of the compensation capacitor 1, and thus improves the reliability of the track circuit system.

[0067] The embodiment also provides a manufacturing method of the track circuit compensation capacitor 1 with the double-core sub-series structure, and a preferred process flow is as follows: core winding-core gold spraying-core heat setting-single core testing-double core series welding-double core testing-lead welding-terminal crimping-curing-packing and pouring.

[0068] The manufacturing method specifically includes the following steps.

[0069] Core winding: a metalized dielectric film is wound into a capacitor core after being formed by a winding device; in this embodiment, the capacitor core is a thin film capacitor, and the metalized dielectric film is wound into a capacitor core after being formed by a winding device.

[0070] Core gold spraying: a metal layer is sprayed on two end faces of the capacitor core as an outgoing electrode of the capacitor; in this embodiment, the capacitor core is a cylindrical type, and a metal layer, generally zinc or zinc-tin alloy, is sprayed on two end faces of the cylindrical core as an outgoing electrode of the capacitor.

[0071] Core heat setting: the capacitor core after gold spraying is subjected to heat setting treatment; in this embodiment, the capacitor core is placed in a temperature test box and subjected to heat treatment at a certain temperature.

[0072] Single core testing: a single capacitor core is tested and selected, and the test indexes include capacitance, loss tangent tan δ and voltage resistance; this step is a core selection test, and unqualified cores are removed.

[0073] Double-core sub-series welding: for the single-core sub which passes the test, two capacitor cores are connected in series by copper foil welding; this step is a special step for making the double-core sub-series compensation capacitor 1, and in this embodiment, two capacitor cores are connected in series by metal copper foils 11, that is, the copper foils are bonded with the end face plating gold layer by soldering tin 10, as shown in Figure 5 The two lead wires 9 (i.e. the two metal copper foils 11) are welded in this embodiment, and one or more lead wires 9 can be welded according to the production requirements in the specific implementation. The two capacitor cores are connected in series by copper foil welding, which is convenient to construct and reliable in connection, and can well meet the quality requirements of the double-core sub-series.

[0074] Double-core sub test: the double-core sub after series connection is tested and screened, and the test indexes include capacitance, loss tangent tan delta and voltage resistance; this step is a screening test on the double-core sub after series welding, and the unqualified double-core sub is removed.

[0075] Lead wire 3 welding: for the double-core sub which passes the test, the lead wire 3 is welded on the end face of the double-core sub on both sides; in this embodiment, the end face of the two capacitor cores on both sides of the double-core sub is connected with one end of the lead wire 3 by soldering tin 10.

[0076] Terminal crimping: the plug pin head 2 or copper wire terminal is crimped at the end of the lead wire 3 away from the double-core sub by using a crimping device; in this embodiment, the plug pin head 2 or copper wire terminal is crimped with the other end of the lead wire 3 by using a crimping device.

[0077] Rubber sheath vulcanization: the connection between the plug pin head 2 or copper wire terminal and the lead wire 3 is wrapped with a rubber sheath and then subjected to vulcanization treatment; in this embodiment, the connection between the plug pin head 2 or copper wire terminal and the lead wire 3 is wrapped with a rubber sheath and then subjected to vulcanization treatment, so as to improve the sealing and waterproof performance of the connection.

[0078] Assembly and pouring: the double-core sub is assembled into a shell and then filled with epoxy pouring material for curing protection. After the completion of the foregoing steps, the double-core sub is placed into a shell (including a metal shell 8 and a plastic shell 4) and then filled with epoxy pouring material (i.e. epoxy resin 7), and the epoxy pouring material plays a sealing and protection role on the capacitor after curing.

[0079] Based on the same inventive concept, the utility model also provides a track circuit, the track circuit includes the track circuit compensation capacitor 1 as mentioned above.

[0080] The parts not involved in this embodiment are the same as or can be realized by the prior art, and will not be further described here.

[0081] Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features therein can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. A track circuit compensation capacitor, two ends of the compensation capacitor are connected to two rails of a track respectively, characterized in that, the compensation capacitor is a double core in series; the compensation capacitor comprises a first core and a second core; the first core and the second core are in series, and one side of the first core away from the second core and one side of the second core away from the first core are connected with a lead wire.

2. The track circuit compensation capacitor according to claim 1, characterized in that, the first core and the second core are connected in series by copper foil welding; one end face of the first core and the second core is provided with a gold plating layer, and the gold plating layer is connected with one end of the lead wire by welding.

3. The track circuit compensation capacitor according to claim 2, characterized in that, the other end of the lead wire is provided with a peg head or a copper terminal, and the lead wire is connected to the rail of the track through the peg head or the copper terminal.

4. The track circuit compensation capacitor according to claim 1, characterized in that, it further comprises a metal shell; the first core and the second core are arranged in the metal shell.

5. The track circuit compensation capacitor according to claim 4, characterized in that, it further comprises a plastic shell; the metal shell is wrapped with the plastic shell; the first core and the second core and the metal shell, and the metal shell and the plastic shell are filled with epoxy resin potting.

6. A track circuit compensation capacitor according to any one of claims 1-5, characterised in that, it further comprises a monitoring module for monitoring the state of the compensation capacitor; the monitoring module is arranged outside the compensation capacitor; the monitoring module comprises a current sensor and a collection and processing unit; the current sensor is used for monitoring the current flowing through the compensation capacitor; the collection and processing unit is used for processing and analyzing the current signal monitored by the current sensor and giving positioning early warning and alarm information.

7. The track circuit compensation capacitor according to claim 6, characterized in that, the compensation capacitor has a unique device address; the collection and processing unit comprises a collection submodule, a communication submodule, an external server and a track circuit diagnosis system; the collection submodule is used for collecting detection data of the current sensor, and sending the detection data to the external server through the communication submodule; the external server uploads the detection data to the track circuit diagnosis system after operation processing; the track circuit diagnosis system analyzes the uploaded data and gives positioning early warning and alarm information according to the device address of the compensation capacitor.

8. A track circuit, characterized in that The track circuit comprises the track circuit compensation capacitor according to any one of claims 1-7.

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