Anomaly detection method for current collector

Abstract

To provide an anomaly detection method for a current collector that is able to appropriately grasp a maintenance timing of the current collector by detecting an anomaly in lift force of the current collector.SOLUTION: An anomaly detection method for a current collector of a railway vehicle including two or more current collectors, includes: a collected current detection step of detecting a collected current of each of the two or more current collectors; a diversion ratio calculation step of calculating a diversion ratio of each of the collected currents; an accumulation step of accumulating calculation results of the diversion ratios; an evaluation value calculation step of calculating an evaluation value of the calculation results accumulated in the accumulation step; and a comparison step of comparing the calculation result of the diversion ratio with the evaluation value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an abnormality detection method for detecting an abnormality in a current collector attached to the top of a railway vehicle. [Background technology]

[0002] Railway vehicles are fitted with a current collector on top. A widely known type of current collector installed on such railway vehicles is a pantograph, which presses the current collector shoe against the overhead wire with a certain force (for example, about 50 N) using the force of a coil spring or air pressure, and has a frame with an articulated or expandable structure to follow changes in the overhead wire height. The current collector shoe takes in the power of the overhead wire while sliding in direct contact with the wire, and the part of the current collector shoe that slides against the overhead wire is equipped with a sliding plate, and the sliding plate is made of carbon or copper alloy, which have good conductivity and are less likely to cause wear on the overhead wire.

[0003] Each railway vehicle is equipped with multiple current collecting devices, and a condition in which any current collecting device is unable to collect current is called electrical disconnection. If there is icing or frost on the overhead wire, the overhead wire and the current collecting shoe can mechanically disconnect, generating an arc and potentially damaging the current collecting shoe.

[0004] In order to prevent such damage, various methods for detecting disconnection of a current collector are known.

[0005] The current collection monitoring device described in Patent Document 1 is a current collection monitoring device installed in a railway vehicle equipped with a first current collecting device and a second current collecting device, and comprises a detection unit that detects a first current flowing through the first current collecting device and a second current flowing through the second current collecting device, and a judgment unit that judges the need for regulation of the current collection current of the railway vehicle based on the first current and the second current detected by the detection unit, and the judgment unit judges that regulation of the current collection current is necessary when the sum of a first non-current time during which the first current is not flowing and a second non-current time during which the second current is not flowing during a certain aggregation time exceeds a threshold value.

[0006] According to such a collection current monitoring device, the sum of the time when no current flows through each collector (i.e., the first non-current time and the second non-current time) is used to determine collection current regulation, so that a state in which an abnormality such as a failure has occurred in one of the collectors can be excluded from the scope of collection current regulation, while collection current regulation can be implemented for a state in which an abnormality exists in the overhead line.

[0007] The current collection monitoring device described in Patent Document 2 includes a current value acquisition unit that acquires a current value I1 of a current collection current flowing through a first current collector and a current value I2 of a current collection current flowing through a second current collector, a first RMS calculation unit that calculates a root mean square RMS1 of the current value I1, a second RMS calculation unit that calculates a root mean square RMS2 of the current value I2, and an unbalanced current calculation unit that calculates an unbalanced current Iu that is a value obtained by subtracting one of the root mean square RMS1 and the root mean square RMS2 from the other. the change amount calculation unit calculating a change amount ΔIu which is the amount of change per unit time in the unbalance current Iu; a change amount average calculation unit calculating a time average value aveΔIu which is the time average value of the absolute value of the change amount ΔIu over a preset time P; a judgment unit judging whether the time average value aveΔIu is greater than a preset threshold value; and an abnormality occurrence signal output unit outputting an abnormality occurrence signal when the judgment unit judges that the time average value aveΔIu is greater than the threshold value.

[0008] According to such a current collecting monitor, when an arc is likely to occur in the first current collecting device or the second current collecting device (for example, when there is frost on the overhead line), an abnormality occurrence signal can be output. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2020-28173 A [Patent Document 2] JP 2019-221107 A Summary of the Invention [Problem to be solved by the invention]

[0010] However, the current collector collects current by sliding its slider against the overhead wire, and the slider wears and changes its shape due to the sliding against the overhead wire, and depending on the shape of the worn slider when a railway vehicle travels at high speed, a negative lift (downward aerodynamic force) is generated on the current collector, and if the lift is large, it may exceed the force of the coil spring or the air pressure that presses the current collector against the overhead wire, causing the current collector to descend and making it unable to collect current. It is also possible that a failure of the mechanism that presses the current collector against the overhead wire may cause the current collector to be unable to collect current.

[0011] Conventional current collection monitoring devices are unable to detect abnormalities in the lift of the current collector or failure of the current collector caused by changes in shape due to wear of the sliders. It is expected that if such abnormalities can be detected in advance, it will be possible to properly determine when to replace the sliders or when to perform maintenance on the current collector.

[0012] Therefore, the present invention has been made in consideration of the above-mentioned problems, and aims to provide a method for detecting abnormalities in a current collecting device, which can properly grasp the timing of maintenance for the current collecting device by detecting abnormalities in the lifting force of the current collecting device. [Means for solving the problem]

[0013] The method for detecting an abnormality in a current collecting device of the present invention is a method for detecting an abnormality in the current collecting device of a railway vehicle equipped with two or more current collecting devices, and is characterized in that it comprises a current collecting current detection process for detecting the current collecting current of each of the two or more current collecting devices, a current division ratio calculation process for calculating the current division ratio of each of the current collecting devices, an accumulation process for accumulating the calculation results of the current division ratio, an evaluation value calculation process for calculating an evaluation value of the calculation results accumulated in the accumulation process, and a comparison process for comparing the calculation result of the current division ratio with the evaluation value.

[0014] In addition, in the method for detecting an abnormality in a collector device according to the present invention, it is preferable that the collector current detection process simultaneously acquires detection position information at which the collector current is detected, and the comparison process compares the evaluation value and the calculation result at the same detection position.

[0015] In addition, in the method for detecting an abnormality in a current collecting device according to the present invention, it is preferable that the comparison process notifies that the current collecting device is abnormal if the difference between the evaluation value and the calculation result exceeds a predetermined threshold value.

[0016] In addition, the method for detecting an abnormality in a current collecting device according to the present invention preferably further comprises a statistical value calculation step of calculating a statistical value of the current collecting current detected in the current collecting current detection step.

[0017] The above summary of the invention does not list all of the necessary features of the present invention, and any subcombination of these features may also constitute an invention. Effect of the Invention

[0018] The method for detecting an abnormality in a current collecting device according to the present invention calculates the current division ratio of the collecting current of two or more current collecting devices and compares the calculated current division ratio with the average value of the accumulated calculation results, so that a tendency for a decrease in the lift force of the current collecting device can be detected from the current division ratio. [Brief description of the drawings]

[0019] [Figure 1] 1 is a schematic diagram of a railway vehicle to which a method for detecting an abnormality in a current collecting device according to an embodiment of the present invention is applied; [Diagram 2] FIG. 4 is a flow diagram of a storage process of the method for detecting an abnormality in a current collecting device according to an embodiment of the present invention. [Diagram 3] FIG. 4 is a flow diagram of a method for detecting an abnormality in a current collecting device according to an embodiment of the present invention. [Figure 4] 5 is a graph illustrating a comparison process of the method for detecting an abnormality in a current collecting device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Preferred embodiments for carrying out the present invention will be described below with reference to the drawings. Note that the following embodiments do not limit the inventions according to the claims, and all of the combinations of features described in the embodiments are not necessarily essential to the solution of the invention.

[0021] FIG. 1 is a schematic diagram of a railway vehicle to which a method for detecting an abnormality in a current collecting device according to an embodiment of the present invention is applied, FIG. 2 is a flow diagram of the accumulation process of the method for detecting an abnormality in a current collecting device according to an embodiment of the present invention, FIG. 3 is a flow diagram of the method for detecting an abnormality in a current collecting device according to an embodiment of the present invention, and FIG. 4 is a graph explaining the comparison process of the method for detecting an abnormality in a current collecting device according to this embodiment of the present invention.

[0022] 1, the method for detecting an abnormality in a current collecting device according to this embodiment is suitably used as a method for detecting an abnormality in a current collecting device 10 provided on a railway vehicle 1 traveling on a track 2. The railway vehicle 1 travels while supplying electric power to the current collecting device 10 installed on the roof of the railway vehicle body 3 by sliding contact with an overhead line 4.

[0023] The current collector 10 comprises a current collector body 11 attached to the roof of the railway car body 3, a frame 12 extending from the current collector body 11 towards the overhead wire 4, and a current collector boat attached to the tip of the frame 12 and equipped with a sliding plate 13 in sliding contact with the overhead wire 4. The railway car 1 is formed by coupling a plurality of railway car bodies 3 not equipped with the above-mentioned railway car bodies 3 or current collectors 10, and two or more current collectors 10 are provided in the entire railway car 1.

[0024] The current collector main body 11 is equipped with a spring portion (not shown), and the elastic force of the spring portion urges the frame body 12 upward so that the slider 13 contacts the overhead line 4 with a predetermined contact force (for example, approximately 54 N).

[0025] The current collector 10 supplies electric power to the railcar 1 by the sliding contact of the slider 13 with the overhead wire 4, but the shape of the slider 13 may change due to wear caused by the overhead wire 4. In this way, the change in shape of the slider 13 may cause a negative lift (downward aerodynamic force) on the slider 13, which may reduce the contact force of the slider 13. Such a reduction in contact force may also be caused by physical failure of the spring portion or frame 12 built into the current collector body 11.

[0026] In addition, when multiple current collecting devices 10 electrically connected to one train of railway vehicles 1 collect current from overhead lines 4, the ratio of the magnitude of the current collected from each current collecting device 10 changes depending on the relative positions of the railway vehicles and ground equipment such as substations and sectioning posts.

[0027] Furthermore, in addition to the positional relationship with the ground equipment, the ratio of the magnitude of the collected currents also changes depending on the current collection performance of each current collector 10. One of the parameters that affects the current collection performance when the railway vehicle 1 is running is the lifting force of the current collector 10. It is known that a current collector 10 whose lifting force is lower than normal due to some factor will have a higher contact resistance (electrical resistance) between the overhead line 4 and the current collector 10 and a higher frequency of contact loss. When current is collected by a current collector 10 with an abnormality in this way, the current collected by the railway vehicle 1 is compensated for by the shortage caused by the abnormality being collected from the other current collectors 10 in the train.

[0028] Therefore, as shown in Figures 2 and 3, the method for detecting an abnormality in a current collecting device of this embodiment is a method for detecting an abnormality in the current collecting device of a railway vehicle equipped with two or more current collecting devices, and includes a current collecting current detection process (S101) for detecting the current collecting current of each of the two or more current collecting devices 10, a current division ratio calculation process (S103) for calculating the current division ratio of each of the current collecting devices, an accumulation process (S104) for accumulating the calculation results of the current division ratio, an evaluation value calculation process (S107) for calculating an average value, which is an evaluation value of the calculation results accumulated in the accumulation process, and a comparison process (S108) for comparing the calculation result of the current division ratio with the evaluation value.

[0029] In the following description, the railway vehicle 1 will be described as a train equipped with two current collecting devices 10, a first current collecting device 10a and a second current collecting device 10b. In addition, when similar processes are performed for each of the current collecting devices 10a and 10b, the processes will be described for the current collecting device 10.

[0030] The collected current detection step (S101) measures and acquires data on the collected current collected by the current collector 10 from the overhead line 4 using an ammeter (not shown) provided on the railway vehicle 1. Any type of ammeter that is conventionally known can be used, and any type of ammeter can be used as long as it can measure the collected current.

[0031] In the collected current calculation step (S101), the collected current is detected for each of the first current collector 10a and the second current collector 10b.

[0032] Next, a statistical value calculation step (S102) is performed to calculate the RMS value of each of the current collecting devices 10a and 10b measured in the current collecting current detection step (S101) in a time interval window of Δt. Here, Δt is a parameter that is adjusted according to the noise level of the acquired data and the dynamic behavior of the current collecting device 10 during running. This step allows subsequent calculations to be easily performed by calculating the RMS value, which is a statistical value, from the raw data of the measured current collecting current.

[0033] In the above-mentioned statistical value calculation step (S102), the RMS value is used as the statistical value, but various conventionally known statistical values ​​can be used. Also, since the method of calculating the RMS value is conventionally known, detailed description thereof will be omitted.

[0034] In the current division ratio calculation step (S103), the current division ratio of the first current collector 10a and the second current collector 10b is calculated. Specifically, the current division ratio R=I A / (I A +I B ) or R=I B / (I A +I B ), where I Ais the RMS value of the current collected by the first current collector 10a, I B is the RMS value of the current collection of the second current collector 10b.

[0035] In the storing step (S104), the flow division ratio calculated in the flow division ratio calculating step (S103) is stored. In addition, various conditions obtained in the environment measuring step (S105) and the tagging step (S106) are simultaneously stored and compiled into a database.

[0036] Here, the environmental measurement process (S105) measures and detects information such as the running speed of the railway vehicle 1, environmental information such as weather, temperature, and wind, the state of icing and frost on the overhead wires 4, positional information such as distance from ground facilities such as open sections / tunnel sections and substations, and the presence or absence of oncoming trains.

[0037] In addition, in the tagging step (S106), among the environmental information measured in the environmental measurement step (S105), weather information such as rainy weather and strong wind conditions are tagged as reference data to the corresponding flow division ratio.

[0038] In the evaluation value calculation step (S107), the average value of the calculation results of the diversion ratios accumulated in the accumulation step is calculated as an evaluation value. Here, the evaluation value is stored as a time-series database of the calculation results of the diversion ratios having the same position information. Note that although the evaluation value has been described as an average value, various values ​​may be used as long as the diversion ratio can be appropriately determined.

[0039] Next, the comparison step (S108) in the method for detecting an abnormality in a current collecting device according to this embodiment will be described with reference to FIG.

[0040] In the comparison step (S108), the evaluation value of the already stored division ratio data in the database is compared with the calculation result of the division ratio data obtained by the new measurement.

[0041] At this time, the branch current ratio data having the same position information as the newly measured branch current ratio data is extracted from the position information in the database (S201). Here, it is preferable to extract the same position information from data that matches the conditions of a long-distance section with high reproducibility of the run curve, a section without oncoming vehicles, and the same current collector.

[0042] In addition, after extracting the flow division ratio data having the same position information, the presence or absence of icing frost on the overhead wire is judged (S202). At this time, if icing frost is present, a section without icing frost, such as a tunnel section, is added to the conditions and re-extraction is performed.

[0043] If there is no frost on the overhead wire, the evaluation value distribution of the diversion ratio in the database (mean: μ, standard deviation: σ) is compared with the newly obtained evaluation value of the diversion ratio (S203), as shown in Fig. 4. At this time, if the newly obtained evaluation value δ of the diversion ratio is within a threshold value obtained by adding ασ, which is obtained by multiplying the standard deviation σ of the evaluation value distribution of the diversion ratio in the database by a predetermined coefficient ±α, that is, if μ-ασ<δ<μ+ασ, the lift of the current collector 10 is determined to be normal, and if not, it is determined to be abnormal as there is a high risk that the lift of the current collector will decrease.

[0044] The method for detecting an abnormality in a current collecting device according to this embodiment is preferably executed by a processing means (not shown) provided on board or on the ground of the railway vehicle 1. A processing device such as a computer is preferably used as the processing means. The processing device includes an arithmetic device such as a CPU (Central Processing Unit) that executes the processing program, a ROM (Read Only Memory) that stores the processing program, and a RAM (Random Access Memory) that temporarily stores data required for the CPU's processing. The processing device also preferably includes input devices such as a keyboard, mouse, and touch panel, output devices such as a CRT (Cathode-Ray-Tube) display, liquid crystal display, and printer, and a communication interface.

[0045] Such a processing device is preferably a computer system constructed within a computer, and such computers may, for example, be personal computers, workstations, servers, tablet computers, etc., and various types of computers may be used as long as they operate in accordance with a program such as application software recorded in a storage device, and may be a single computer, or a group of computers in which multiple computers are connected so as to be able to communicate via a network or the like.

[0046] In this way, according to the method for detecting abnormalities in a current collector in this embodiment, if the shape of the slider 13 of the current collector 10 changes due to wear, or if the lift force decreases due to mechanical damage to the current collector 10, the newly measured current division ratio of the current collector 10 can be compared with a database accumulated as the railway vehicle 1 runs, making it possible to grasp the trend of a decrease in the lift force of the current collector 10 and perform appropriate maintenance management.

[0047] In addition, in the method for detecting an abnormality in a current collector according to the present embodiment described above, a railway vehicle equipped with two current collectors 10 has been described, but the number of current collectors can be changed as appropriate as long as it is two or more. In addition, although the statistical values ​​and evaluation values ​​have been described using RMS values ​​and average values, other conventionally known values ​​may be used as long as an appropriate evaluation can be performed. It is clear from the claims that such modified or improved forms are also included in the technical scope of the present invention. [Explanation of symbols]

[0048] 1 railway vehicle, 2 track, 3 vehicle body, 4 overhead line, 10 current collector, 10a first current collector, 10b second current collector, 11 current collector body, 12 frame, 13 slider, S101 current collector current detection process, S103 current division ratio calculation process, S104 accumulation process, S107 evaluation value calculation process, S108 comparison process.

Claims

1. A method for detecting an abnormality in a current collecting device of a railway vehicle having two or more current collecting devices, comprising: a current collecting detection step of detecting a current collecting current of each of the two or more current collecting devices; a current division ratio calculation step of calculating a current division ratio of each of the collected currents; a storage step of storing the calculation result of the flow division ratio; an evaluation value calculation step of calculating an evaluation value of the calculation results accumulated in the accumulation step; A method for detecting an abnormality in a current collecting device, comprising: a comparison step of comparing a result of the calculation of the current division ratio with the evaluation value.

2. The method for detecting an abnormality in a current collecting device according to claim 1, The current collection detection step includes simultaneously acquiring detection position information at which the current collection current is detected, The method for detecting an abnormality in a current collecting device, wherein the comparing step includes comparing the evaluation value and the calculation result at the same detection position.

3. The method for detecting an abnormality in a current collecting device according to claim 1, A method for detecting an abnormality in a current collecting device, characterized in that the comparison process notifies that the current collecting device is abnormal if the difference between the evaluation value and the calculation result exceeds a predetermined threshold.

4. The method for detecting an abnormality in a current collecting device according to claim 1, A method for detecting an abnormality in a current collecting device, comprising: a statistical value calculation step of calculating a statistical value of the current collecting current detected in the current collecting current detection step.

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