JP2023081545A - Ground resistance deterioration position estimation device and method of the same - Google Patents

Abstract

To reduce a maintenance load of ground resistance maintenance by estimating a deterioration position of ground resistance.SOLUTION: A ground resistance deterioration position estimation device for estimating a ground resistance deterioration position in a target route comprises: a ground resistance deterioration-time rail ground voltage calculation unit which calculates a rail ground voltage candidate value based on a predicted position where there is a possibility of ground resistance deterioration for each of plural positions and stores the value in a manner of being able to output the value; a rail ground voltage acquisition unit which acquires rail ground voltage measurement values at the plural positions in a target route; and a ground resistance deterioration position collation unit which selects the predicted position where the approximate tendency is found as the ground resistance deterioration position on the basis of the result of comparing and collating the rail ground voltage measurement values with the rail ground voltage candidate value. The ground resistance deterioration position collation unit, when there is the tendency of approximating the rail ground voltage candidate value at each of the plural position, sets the ground resistance deterioration position with the approximation obtained by dividing the predicted positions across the plural positions according to the degree of approximation.SELECTED DRAWING: Figure 1

Description

The present invention relates to a ground resistance degradation position estimating apparatus and method for estimating a ground resistance degradation (lowering) position on a return line formed by rails of an electric railway.

In order to prevent electrolytic corrosion caused by stray (leakage) current from return lines of electric railways, the international standard IEC62128 defines the permissible amount of stray current per year.

Also, there is known a method of clarifying the actual state of a stray current from a return line from an electric train to a substation using a simulation model formed of an equivalent circuit and a calculation formula (for example, Patent Document 1).

Also known is a method of monitoring rail-to-ground voltages measured at a plurality of positions and determining that stray current is abnormal when the rail-to-ground voltages deviate from a reference range (for example, Patent Document 2).

JP 2015-123778 A EP1391741A1

When the ground resistance has deteriorated, it is necessary to carry out maintenance such as part replacement and cleaning at the stage where the deterioration is detected. However, since the inspection range extends over a wide range, frequent inspections impose a heavy maintenance burden.

With the technique of Patent Document 1, the rail-to-ground voltage and rail leakage current of a DC electric railway can be clarified by simulation. However, with this technology, it is not possible to estimate the deteriorated position of the ground resistance in the return line formed by the rail extending on the target route as a positive electrolytic corrosion prevention measure.

Moreover, by using the technique disclosed in Patent Document 2, it is sufficient to detect the occurrence of an abnormal stray current and perform an inspection at the stage of detection. Therefore, the technology can reduce the frequency of inspections, contributing to a reduction in maintenance burden. However, the technique disclosed in Patent Literature 2 cannot estimate the deterioration position of the ground resistance, which is the cause of the stray current.

For this reason, it is necessary to inspect a wide area in order to find the position where the deterioration of the ground resistance occurs, requiring manpower and time for maintenance. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to provide a ground resistance deterioration position estimating device that reduces the maintenance burden of maintaining ground resistance by estimating the deterioration position of the ground resistance. to do.

The present invention for solving the above problems is a ground resistance deterioration position estimating device for estimating a ground resistance deterioration position in a target route, and is provided with a plurality of rail-to-ground voltage candidate values based on predicted positions where there is a possibility of ground resistance deterioration. a rail-to-ground voltage calculation unit that calculates and stores the rail-to-ground voltage when the ground resistance deteriorates and can be output each time; a ground resistance deterioration position matching unit that selects an expected position where a similar tendency is found based on the result of comparing and matching the rail-to-ground voltage candidate value and making it the ground resistance deterioration position.

According to the present invention, it is possible to provide an earth resistance deterioration position estimating device that reduces the maintenance burden of maintaining earth resistance by estimating the earth resistance deterioration position.

1 is an example of a configuration of a ground resistance deterioration position estimation device (hereinafter also referred to as "this device") according to Embodiment 1 of the present invention; 2 is a flow chart showing an operation procedure in a rail-to-ground voltage calculator of FIG. 1; It is an example of a simulation pattern in the apparatus of FIG. It is an example of a retrace resistance model assuming that the ground resistance is one layer, which is used for calculating the rail-to-ground voltage in the device of FIG. It is an example of a retrace resistance model assuming two layers of ground resistance, which is used for calculating the rail-to-ground voltage in the apparatus of FIG. 2 is an example of an equivalent circuit diagram for explaining a method of calculating a rail-to-ground voltage in the device of FIG. 1; FIG. FIG. 2 is a flow chart showing an operation procedure of a ground resistance deterioration position matching unit in FIG. 1; FIG. FIG. 8 is a graph for explaining the rail-to-ground voltage comparison process in step S702 of FIG. 7; FIG. It is an example of the configuration of a ground resistance deterioration position estimation device (also referred to as "this device") according to a second embodiment of the present invention. FIG. 10 is an example of processing in the rail-to-ground voltage calculator in FIG. 9 ; FIG. 11 is a histogram for explaining the processing in step S1002 of FIG. 10;

The apparatus according to the first embodiment will be described below with reference to FIGS. 1 to 8, and the apparatus according to the second embodiment will be described with reference to FIGS. 9 to 11. FIG. Most of the units and processes shown here are implemented by a computer that constitutes the device by executing a program stored in its memory. Each part formed by software is not necessarily a component that can be visibly separated like hardware, and its shape, affiliation, and installation place can be changed in any way. Furthermore, the names of each part and each process are merely examples, and other synonyms are also included in the present invention.

[composition]
The configuration of this device will be described with reference to FIG. The apparatus illustrated in FIG. 1 includes a rail-to-ground voltage acquisition unit 101, a position current acquisition unit 102, a rail-to-ground voltage calculation unit when the ground resistance deteriorates (also referred to simply as a "rail-to-ground voltage calculation unit") 103, and a ground resistance deterioration position It is composed of a collation unit 104 , a ground resistance deterioration position notification unit 105 , and a date and time designating unit 106 .

The rail-to-ground voltage acquisition unit 101 measures the voltages of the rail and the ground electrode at a plurality of positions on the route, and records them in a form that can be retrieved at a specified date and time. Then, when the specified date and time 190 is received, the rail-to-ground voltage at the specified date and time is output to the ground resistance deterioration position matching unit 104 as the rail-to-ground voltage actual measurement result 111 .

The position current acquisition unit 102 acquires the running positions and currents of all electric vehicles running on the target line, the positions of the substations on the target line and the currents there, and records them in a form that can be searched on a specified date and time. When the specified date and time 190 is received, the current and position information at the specified date and time is output to the rail-to-ground voltage calculator 103 as the position current information 112 .

The rail-to-ground voltage calculation unit 103 inputs the specified date and time 190 and the position current information 112, calculates the rail-to-ground voltage at the specified date and time, and sends it to the ground resistance deterioration position matching unit 104 as the rail-to-ground voltage calculation result 113 at the time of ground resistance deterioration. Output. Details of the rail-to-ground voltage calculator 103 will be described later.

The ground resistance deterioration position matching unit 104 inputs the specified date and time 190, the rail-to-ground voltage actual measurement result 111, and the rail-to-ground voltage calculation result 113 at the time of ground resistance deterioration, and compares the position where the ground resistance is deteriorated. A deteriorated position estimation result 114 is output to the ground resistance deteriorated position notification unit 105 . The details of the ground resistance deterioration position matching unit 104 will also be described later.

The ground resistance deterioration position notification unit 105 receives the ground resistance deterioration position comparison result 114 and notifies the system user of the ground resistance deterioration position. The notification method may be at least one of board lighting display, screen display, voice, print output on paper, and similar display. As described above, any notification method can be used as long as the system user can grasp the estimated ground resistance deterioration position.

The date and time specifying unit 106 outputs the date and time specified by the operator's operation as the specified date and time 190 using the date and time specifying operation by the operator as a trigger.

[Rail-to-ground voltage calculator]
FIG. 2 is a flow chart showing the operation procedure of the rail-to-ground voltage calculator 103. As shown in FIG. As shown in FIG. 2, the rail-to-ground voltage calculator 103 executes the processes of steps S201 to S205. As described above, each part serving as an execution subject shown in FIG. 1 is formed by software and cannot be visually recognized separately. In addition, the execution subject in the description without a subject is this apparatus.

In step S201, a retrace resistance model is created, and the process proceeds to step S202. Details of the retrace resistance model created in step S201 will be described later with reference to FIGS. 4 and 5. FIG.

In step S202, the position current acquisition unit 102 acquires the positions of the train and the substation at the designated date and time and the currents there, and proceeds to step S203.

Step S203 is a loop process, and the process of step S204 is repeated by the number of simulation patterns, and when the repetition is completed, the process proceeds to step S205. Simulation patterns will be described later.

In step S204, the rail-to-ground voltage calculator 103 connects the low resistance 611 to the retrace resistor and calculates the rail-to-ground voltage. A method of calculating the rail-to-ground voltage in step S204 will be described later.

In step S205, all the rail-to-ground voltages calculated by repeating step S204 are output as the rail-to-ground voltage calculation result 113 when the ground resistance is deteriorated, and the process ends.

[Simulation pattern]
This device displays the value of the rail-to-ground voltage when the ground resistance deteriorates, corresponding to a plurality of positions in the target route, as a deterioration sample based on at least one of the calculated value by simulation calculation and the acquired past value. Stored so that it can be output as On the other hand, the present device acquires rail-to-ground voltage actual measurements at observation points corresponding to the plurality of positions.

In addition, the device compares and collates the stored deterioration sample and the rail-to-ground voltage actual measurement value with respect to patterns corresponding to the plurality of positions, that is, waveform tendencies. If the patterns match as a result of the above comparison and collation, the present apparatus regards the deterioration position set in the deterioration sample as the ground resistance deterioration position. Such a simulation pattern will be described with reference to FIG.

As shown in FIG. 3, the simulation pattern consists of a low resistance pattern number, an installation number line for installing the low resistance 611, a position for installing the low resistance 611, and a resistance value of the low resistance 611. FIG. Also, a plurality of low-resistance installation positions may be set in one simulation pattern. In that case, although omitted in FIG. 3, two or more ground wires, low-resistance installation positions, and resistance values are set with the same low-resistance pattern number.

A simulation pattern is manually set through an interface or the like. Since the variation of the low-resistance installation position increases as the route becomes longer in the simulation pattern, it takes time to calculate all the patterns if the grounding positions are comprehensively set.

Therefore, it is desirable to narrow down the target position by finding a position where ground resistance deterioration is likely to occur. As a position where ground resistance deterioration is likely to occur, for example, a position where it has been confirmed that ground resistance deterioration has actually occurred in the past can be considered.

On the rails of electric railways, near stations where electric cars depart and stop frequently, the ground resistance tends to deteriorate because iron powder, etc. generated when electric cars decelerate with air brakes are scattered. there is a possibility.

Another reason is that power running and regeneration are performed in the vicinity of the station, and the rail-to-ground voltage tends to become relatively high in the positive and negative directions. Insulating members such as rail pads installed in such places are considered to be relatively susceptible to insulation deterioration.

Other than that, in tunnel sections with high humidity, it is considered to be an environmental condition where moisture adheres to the dust accumulated between the rail and the roadbed, making it easier to conduct. I can guess. In this way, it is desirable to set a simulation pattern in which the low resistance 611 simulating the deterioration is installed at a position where the ground resistance is relatively easily deteriorated.

[Retrace resistor model created in step S201]
FIG. 4 is an example of a retrace resistance model assuming that the ground resistance is one layer, which is used for calculating the rail-to-ground voltage in the device of FIG. As shown in FIG. 4, when there are an up line 401, a down line 402, and a crossover line 403 connecting the up and down lines, feedback is provided by rail resistance 410a, rail resistance 410b, rail resistance 410c, ground resistance 420a, and ground resistance 420b. Line resistance is configured.

A parameter of the rail resistance 410 is defined as Ω/km, and a parameter of the ground resistance 420 is defined as S/km, and the resistance value is determined according to the length of the line. The interval between the grounding resistors 420 can be set arbitrarily, and is generally set at intervals of several hundred meters.

In addition, in FIG. 4, the crossover 403 is simulated by a rail resistance, but it is not limited to this. Since the crossover 403 may be short and may not affect the calculation accuracy, it may be simulated by connecting the crossover positions of the up and down lines at the same node instead of simulating with the rail resistance.

Also, in FIG. 4, the electrical connection between the up and down lines is only the crossover wire 403, but it is not limited to this. When a cable such as a rail tie is used instead of the crossover wire 403, it is desirable to simulate by connecting the rail resistance nodes of the upper and lower lines in the same manner as the connection by the crossover wire.

In addition, although FIG. 4 illustrates the case where the ground resistance is one layer, the present invention is not limited to this. As shown in FIG. 5, a rail-direction resistor 501 and a depth-direction resistor 502 may be added, and the retrace resistor may be composed of multiple layers of grid-like resistors. FIG. 5 is an example of a retrace resistance model assuming two layers of ground resistance, which is used for calculating the rail-to-ground voltage in the device of FIG. In this way, the computational accuracy of the retrace resistance model can be further improved.

It is desirable that the resistance value of the ground resistor 420 is set to an appropriate value for each position. For example, the above-ground section, where gravel is laid on the ground and rails are laid, the elevated section, where rails are laid on a concrete elevated bridge, and the tunnel section, where rails are laid in underground tunnels, have different grounding resistances. It is desirable to set the resistance value of the ground resistance value in consideration.

Also, even in above-ground sections and elevated sections, the ground resistance is generally lowered by moisture in rainy weather, so it is desirable to change the ground resistance according to the weather.

[Rail-to-ground voltage calculation method in step S204]
FIG. 6 is an example of an equivalent circuit diagram for explaining the method of calculating the rail-to-ground voltage in the device of FIG. First, in the retrace resistance model created in step S201, a low resistance 611 is added to the position associated with the currently referenced simulation pattern number.

Next, the train currents (a) and (b) and the substation current are input to the nodes corresponding to the train position and the substation position included in the position current information 112, and the voltage of each node is calculated. The potential of the node across each rail resistor is output as the rail-to-ground voltage.

[Earth resistance deterioration position matching unit]
FIG. 7 is a flow chart showing the operation procedure of the ground resistance deterioration position matching unit 104 of FIG. In FIG. 7, step S701 is a loop process, and the process of step S702 is repeated by the number of patterns of the rail-to-ground voltage calculation result 113 when the ground resistance is deteriorated, and when the repetition is completed, the process proceeds to step S703.

In step S702, the rail-to-ground voltage of the measured rail-to-ground voltage result 111 and the rail-to-ground voltage calculation result 113 of the rail-to-ground voltage when the ground resistance deteriorates are compared. is updated as a ground resistance deterioration pattern candidate. The details of the process of step S702 will be described later.

In step S<b>703 , the ground resistance deterioration position of the ground resistance deterioration pattern candidate at the stage when the loop processing S<b>701 ends is output as the ground resistance deterioration position comparison result 114 .

[Processing of step S702]
FIG. 8 is a graph for explaining the rail-to-ground voltage comparison process in step S702 of FIG. In FIG. 8, the vertical axis is the rail-to-ground voltage 801, and the horizontal axis is the position. is a graph.

Distinguishing between rail-to-ground voltage calculation result A when the earth resistance is degraded (also simply referred to as “calculation result A”) and rail-to-ground voltage calculation result B when the earth resistance is degraded (simply referred to as “calculation result B”) is as follows: Calculation results A and B are rail-to-ground voltage calculation results for different ground resistance deterioration positions, ie, different low-resistance installation positions, and are included in the rail-to-ground voltage calculation result 113 .

The locations where the plots in the graph are generated are the locations where the measured rail-to-ground voltage values were measured. As the simplest comparison method, there is a method of comparing the voltage at the same position in the actual measurement result and the calculation result, and using the one with the smallest total value of the difference between the two as the ground resistance deterioration pattern candidate.

In the rail-to-ground voltage 801 in FIG. 8, the actual measurement result indicated by the solid line is plotted closer to the actual measurement value for the calculation result A indicated by the dashed line than the calculation result B indicated by the dashed line. Therefore, the apparatus selects the calculation result A as a ground resistance deterioration pattern candidate.

In the example of FIG. 8, a good result was obtained by selecting the ground resistance deterioration pattern candidate that has the smallest difference between the calculation results A and B with respect to the actual measurement result. However, if there is no restriction on the difference between the actual measurement result and the calculation result, there is a possibility of misjudgment as follows.

For example, in FIG. 8, depending on the method of setting the simulation parameters, even if the difference between the calculation results A and B with respect to the actual measurement results is large overall, if it is the smallest among them, the position may differ from the actual position. , it may be erroneously determined that the ground resistance has deteriorated.

Therefore, a threshold value is set for the total value of the difference between the two, and if the total value does not fall below the threshold value, it is necessary to review the simulation parameters in order to identify the ground resistance deterioration position. In that case, by adding a function to notify that a review is necessary to this device, it becomes possible to narrow down the ground resistance deterioration position more appropriately. As a result, the device can efficiently estimate the location of deterioration of the ground resistance.

The apparatus according to the first embodiment calculates the rail-to-ground voltage calculation result 113 when the ground resistance is deteriorated under all the conditions set as the simulation pattern. In this apparatus, after this calculation, a process of comparing the rail-to-ground voltage actual measurement result 111 and collating the ground resistance deterioration position is also executed one by one.

In this first embodiment, the calculation of the rail-to-ground voltage calculation result may be simplified to only one condition in the simulation pattern. A method of repeating the process of comparing the calculation result when the ground resistance is deteriorated under one limited condition and the rail-to-ground voltage actual measurement result 111 for the number of all the conditions set in the simulation pattern is applied. Also good.

In that case, after performing calculation and comparison under the condition that the low resistance installation position is shifted by several kilometers, it is preferable to perform calculation and comparison under the condition that the vicinity of the nearest low resistance installation position is shifted by several hundred meters. By configuring a processing function that searches for detailed low-resistance installation positions, this device can estimate the position where the ground resistance is degraded while achieving both comprehensiveness and calculation time.

The device of the first embodiment measures the rail-to-ground voltage actually measured at a plurality of positions on the target route, and the rail-to-ground voltage value (deterioration sample) obtained in the past or calculated by simulation calculation when the ground resistance is deteriorated. Compare and match. Specifically, the trends (patterns) of waveforms plotted on a graph in which the horizontal axis indicates the position and the vertical axis indicates the rail-to-ground voltage 801 are compared and collated, as illustrated in FIG.

This device estimates the position indicated by the deterioration sample where the tendency (pattern) of the waveform matches as the ground resistance deterioration position. According to this device, it is sufficient to take measures against deterioration only in a narrow range limited to the vicinity of the estimated ground resistance deterioration position, so the maintenance burden for maintaining the ground resistance can be reduced.

[composition]
The configuration of this device according to the second embodiment will be described with reference to FIG. The device of the second embodiment shown in FIG. It is composed of a resistance deterioration position matching unit 904 , a ground resistance deterioration position notification unit 105 , and a ground resistance deterioration position estimation start determination unit 990 .

The rail-to-ground voltage acquisition unit 901 measures the voltages of the rail and the ground electrode at a plurality of positions on the route, stores the time-series data of the rail-to-ground voltage as the rail-to-ground voltage actual measurement result 911, stores the rail-to-ground voltage storage unit 903, the ground resistance It is output to the deterioration position estimation start determination unit 990 and the ground resistance deterioration position comparison unit 904 .

The position current acquisition unit 902 acquires the running positions and currents of all electric vehicles running on the target line, the positions and currents of substations on the target line, and stores the time-series data of the currents and positions as position current information 912. It is output to the rail-to-ground voltage storage unit 903 and the ground resistance deterioration position estimation start determination unit 990 .

The rail-to-ground voltage storage unit 903 records chronological changes in the rail-to-ground voltage, the position of each of the train and the substation, and the current based on the rail-to-ground voltage measurement result 911 and the position current information 912 .

When ground resistance deterioration is confirmed by inspection, etc., the position of ground resistance deterioration is linked to the rail-to-ground voltage and position current information for a certain period of time, stored as the rail-to-ground voltage at the time of earth resistance deterioration, and the rail at the time of earth resistance deterioration Output as ground voltage actual measurement result 913 .

Also, the rail-to-ground voltage and position current information when no deterioration of ground resistance is confirmed by inspection or the like is stored as reference rail-to-ground voltage-related information and output as reference rail-to-ground voltage-related information 923 .

The ground resistance deterioration position matching unit 904 inputs the rail-to-ground voltage actual measurement result 911, the rail-to-ground voltage actual measurement result 913 at the time of earth resistance deterioration, and the ground resistance deterioration position estimation start flag 991, and executes the following processing. .

The ground resistance deterioration position matching unit 904 collates the position where the ground resistance is deteriorated, and outputs the ground resistance deterioration position comparison result 114 to the ground resistance deterioration position notification unit 105 . Details of this process will be described later.

The ground resistance deterioration position estimation start determination unit 990 inputs the rail-to-ground voltage actual measurement result 911, the position current information 912, and the reference rail-to-ground voltage related information 923, and executes the following processing.

The ground resistance deterioration position estimation start determination unit 990 searches for the reference rail-to-ground voltage when the positions and currents of the train and substation contained in the reference rail-to-ground voltage related information 923 match within a predetermined range, and actually measures the rail-to-ground voltage. A comparison with the value of the result 911 is performed.

Furthermore, the ground resistance deterioration position estimation start determination unit 990 determines that there is a possibility that ground resistance deterioration has occurred somewhere when a predetermined deviation occurs in the rail-to-ground voltage at each position. A ground resistance deterioration position estimation start flag 991 is output.

In the second embodiment, an example is described in which the ground resistance deterioration is determined based on the deviation of the rail-to-ground voltage at each position.

On the other hand, as a method to eliminate transient or sudden and trivial phenomena, this device calculates statistics such as the standard deviation and average value of the rail-to-ground voltage at each position for a predetermined period of time. It is preferable to use a method of judging when there is a deviation.

As a result, the apparatus can make appropriate judgments even when the positions and currents of the train and the substation do not completely match the rail-to-ground voltage recorded when the ground resistance deteriorates. Note that the configuration of the ground resistance deterioration position reporting unit 105 is the same as that of the first embodiment, so detailed description thereof will be omitted.

[Earth resistance deterioration position matching part]
The processing of the ground resistance deterioration determination unit 904 in FIG. 10 will be described with reference to FIG. FIG. 10 shows an example of processing in the rail-to-ground voltage calculator 903 according to the second embodiment.

Steps S701 and S703 are the same as the ground resistance deterioration position collating unit 104 in the first embodiment, that is, steps S701 and S703 in FIG. 7, and redundant description will be omitted.

A step S1002 compares the rail-to-ground voltage actual measurement value and the rail-to-ground statistic, and updates the ground resistance deterioration pattern candidate if the two are the closest. The processing of step S1002 will be described in detail with reference to FIG. FIG. 11 is a histogram for explaining the processing in step S1002 of FIG.

In step S1002, the average rail-to-ground voltage and standard deviation for a predetermined period at each position are calculated based on the time-series data of the rail-to-ground voltage measurement result 911 and the rail-to-ground voltage measurement result 913 when the ground resistance is deteriorated. do. Then, the rail-to-ground voltage actual measurement result at the time of ground resistance deterioration that has the closest average value and standard deviation at each position is taken as a ground resistance deterioration pattern candidate.

Rail-to-ground voltage actual measurement result A during earth resistance deterioration (hereinafter also referred to as “actual measurement result A”) and rail-to-ground voltage actual measurement result B during earth resistance deterioration (hereinafter also referred to as “actual measurement result B”) are as follows. means the result of Actual measurement results A and B are actual measurement results of rail-to-ground voltage at different ground resistance deterioration positions, ie, different low-resistance installation positions, and are included in rail-to-ground voltage measurement result 913 at the time of earth resistance deterioration.

As shown in FIG. 11, in this apparatus, the average value and standard deviation of the actual measurement result B are closer than those of the actual measurement result A, so the actual measurement result B, which tends to be more similar, becomes the ground resistance deterioration pattern candidate. Based on the principle described above, the apparatus according to the second embodiment shown in FIGS. 9 to 11 can estimate the position of the rail-to-ground voltage only from the actual measurement values without executing the simulation calculation processing as in the first embodiment.

In FIG. 11, it can be explained from the calculation of the electric circuit that the smaller the fluctuation range of the rail-to-ground voltage, the higher the possibility of the ground resistance deterioration position. This is because if the ground resistance is 0Ω, the rail-to-ground voltage is also 0V regardless of the direction and magnitude of the stray current.

[supplement]
In Example 1, the rail-to-ground voltage when the ground resistance deteriorates was calculated by simulation calculation. On the other hand, in Example 2, the ground resistance deterioration pattern candidate is calculated by comparing the rail-to-ground voltage actual measurement value and the statistic of the rail-to-ground voltage when the ground resistance is deteriorated. The present apparatus can also be realized with a configuration and method that combine the characteristic techniques of the first and second embodiments.

In Example 1, the ground resistance deterioration pattern candidate was calculated by comparing the measured rail voltage to ground, the rail voltage to ground at each position at the time of ground resistance deterioration, and the magnitude relationship of each. On the other hand, in Example 2, the rail-to-ground voltage at the time of deterioration of the ground resistance was output based on the record of the rail-to-ground voltage. The present apparatus can also be realized with a configuration and method that combine the characteristic techniques of the first and second embodiments.

In this case, by adding to the conditions for calculating the ground resistance deterioration pattern candidate that the position currents of the electric train and the substation match within a predetermined range, the ground resistance deterioration position can be determined with higher accuracy. It is possible to estimate

In addition, the present invention is not limited to the above embodiments, and includes various modifications within the scope of the invention. For example, the present invention is not limited to those having all the configurations described in the above embodiments, and includes those with some of the configurations omitted. Also, part of the configuration according to one embodiment can be added to or replaced with the configuration according to another embodiment.

[Stray current]
In an electric railway, a substation, which is a power source, and a vehicle, which is a load, are connected to each other by connecting overhead wires as positive electrodes and rails as negative electrodes to form an electric circuit, thereby supplying the electric power necessary for running the vehicles. When the vehicle is running, current flows from the substation to the vehicle through the catenary, which is the positive electrode, and current flows from the vehicle to the substation through the rail, which is the negative electrode (return current). At this time, part of the return current leaks from the rail to the ground and passes through the ground as stray current back to the substation.

It is known that embrittlement is accelerated by electrolytic corrosion when stray current flows into underground pipes and reinforcing bars of structures around railway facilities. On the other hand, the international standard IEC62128 defines the permissible amount of stray current per year.

This device can be summarized as follows.
[1] As shown in FIGS. 1 and 9, this device is a ground resistance deterioration position estimating device for estimating the ground resistance deterioration position within a target route in an electric railway. This device has rail-to-ground voltage calculators 103 and 903 when the ground resistance is deteriorated, rail-to-ground voltage acquisition units 101 and 901 , and a ground resistance deterioration position checker 104 .

In an electric railway, when the ground resistance deteriorates, it is necessary to carry out maintenance such as parts replacement and cleaning at the stage when the deterioration is detected. However, since the inspection range extends over a wide range, frequent inspections lead to an increase in the maintenance burden. Based on the operating conditions of the electric railroad, a wide range of inspections can be narrowed down to a few possible locations.

The rail-to-ground voltage calculation units 103 and 903 output the rail-to-ground voltage candidate values based on the plurality of predicted positions thus narrowed down and stored. That is, the rail-to-ground voltage calculation units 103 and 903 can calculate and output rail-to-ground voltage candidate values, which are meant as comparison standards or deterioration samples, for each of a plurality of positions based on the predicted positions where there is a possibility of ground resistance deterioration. memorize to

The rail-to-ground voltage candidate value based on the predicted position means a rail-to-ground voltage at each node obtained from an equivalent circuit simulating a return line of an electric railway and a calculation formula. On the other hand, the rail-to-ground voltage acquisition units 101 and 901 acquire rail-to-ground voltage actual measurements at a plurality of positions including at least the predicted position.

Based on the result of comparing and collating the rail-to-ground voltage actual measurement value and the rail-to-ground voltage candidate value, the ground resistance deterioration position matching unit 104, 904 selects and grounds an expected position where a similar tendency (pattern) is found. This is the resistance deterioration position. The degree of deterioration can be estimated according to the approximation of the trend.

In this way, the ground resistance deterioration positions estimated by this device are selected from the predicted positions in descending order of probability of hitting. Therefore, the track maintenance worker should give priority to the positions estimated to be significantly degraded, and perform maintenance. According to this device, it is possible to reduce the maintenance burden of maintaining the ground resistance in the track maintenance work of the electric railway.

[2] As shown in FIGS. 1 and 8, it is estimated that the ground resistance deterioration position is closer to the predicted position indicated by the calculation result A by the amount closer to the calculation result A than to the calculation result B. . In other words, in the above [1], if there is a tendency for each of the plurality of positions to approximate the rail-to-ground voltage candidate value, the ground resistance deterioration position matching units 104 and 904 predict the plurality of positions according to the degree of approximation of the tendency. It is assumed that the ground resistance deterioration position is proportionally close to the position. As a result, the apparatus can more accurately estimate the ground resistance deterioration position.

[3] As shown in FIGS. 1 and 9, in the above [2], at the same time as the acquisition of the measured rail-to-ground voltage value, the position of the electric car on the target line and the position of the power supply equipment, and their currents It further has a position current acquisition unit 102, 902 for acquiring.

The position current acquisition units 102 and 902 acquire the running positions and currents of all electric vehicles running on the target line, the positions and currents of substations on the target line, and record them in a form that can be retrieved on a specified date and time. When the specified date and time 190 is received, the current and position information at the specified date and time is output to the rail-to-ground voltage calculator 103 as the position current information 112 .

Electric railways are generally expected to have several ground resistance deterioration positions based on the operation schedule of electric cars. Therefore, the present device can more precisely estimate the ground resistance deterioration position based on the records that can be retrieved by the specified date and time related to the bus schedule.

[4] As shown in FIGS. 1, 6 and 9, in [2] above, the rail-to-ground voltage calculators 103 and 903 when the ground resistance is deteriorated have the following functions. First, as shown in FIGS. 4 to 6, a ground resistance deterioration return resistance model is created by connecting a low resistance 611 simulating ground resistance deterioration to a return resistance model simulated by a rail resistance 410 and a ground resistance 420. do.

Next, the positions of the electric car and the substation at the time of acquisition of the rail-to-ground voltage measurement value and their currents are input to the ground resistance degradation return line resistance model to calculate the ground voltage across the rail resistance. The ground voltage is output as a rail-to-ground voltage candidate value when the ground resistance is deteriorated. As a result, the present device can more accurately estimate the location of the ground resistance degradation in accordance with the actual facility layout and the positional relationship with the electric vehicle.

[5] As shown in FIGS. 1, 6 and 9, in the above [1] or [4], the rail-to-ground voltage calculation unit 103, 903 at the time of ground resistance deterioration determines whether the ground resistance deterioration has occurred on the target line in the past. The ground resistance deterioration position at the time of the measurement and the rail-to-ground voltage actual measurement values at multiple positions at that time are linked and stored. The apparatus outputs the information thus stored as a rail-to-ground voltage candidate value when the ground resistance deteriorates. As a result, the device can more accurately estimate the ground resistance deterioration position by making use of past empirical rules.

[6] As shown in FIGS. 1 and 9, in [2] above, the ground resistance deterioration position collating units 104 and 904 have the following functions. First, the rail-to-ground voltage actual measurement value at each position and the rail-to-ground voltage candidate value at the time of ground resistance deterioration are compared. Next, a search is made for the rail-to-ground voltage at the time of ground resistance deterioration that has the closest rail-to-ground voltage value at each position.

The ground resistance deterioration position when the rail-to-ground voltage at the time of earth resistance deterioration is recorded or generated is determined as the ground resistance deterioration position. In this way, this device actively searches for the rail-to-ground voltage at the time of ground resistance deterioration that is closest to the value of the rail-to-ground voltage at each position so as to make use of past empirical rules, so that the correct answer can be found. Position can be estimated more accurately.

[7] As shown in FIGS. 1 and 9, in [5] above, the rail-to-ground voltage calculation units 103 and 903 at the time of ground resistance deterioration calculate the position of the electric train and the power supply facility when the measured rail-to-ground voltage value is acquired. Then, under the condition that these currents match within a predetermined range, it selects and outputs the rail-to-ground voltage at the time of earth resistance deterioration recorded in the state where there is earth resistance deterioration.

The current is acquired by position current acquiring units 102 and 902 and supplied to rail-to-ground voltage calculating units 103 and 903 when the ground resistance is deteriorated. As a result, the present device corresponds to the actual equipment layout and the positional relationship with the electric train, and uses the current values acquired by the position current acquisition units 102 and 902 as well as past empirical rules to determine the ground resistance deterioration position. It can be estimated more precisely.

[8] As shown in FIGS. 1 and 9, in [1] above, the ground resistance deterioration position matching units 104 and 904 have the following functions. First, the statistic of the rail-to-ground voltage value at each position over a predetermined period and the statistic of the rail-to-ground voltage at the time of ground resistance deterioration over a predetermined period are calculated.

Next, a search is made for the rail-to-ground voltage during ground resistance deterioration that has the closest statistic at each position. The ground resistance deterioration position when the rail-to-ground voltage at the time of earth resistance deterioration is recorded or generated is estimated as the ground resistance deterioration position. Such an apparatus is simple in computational processing and tends to obtain highly reliable results. For example, the ground resistance deterioration position can be estimated with practical accuracy by calculation processing of a simple computer such as a one-chip microcomputer.

[9] In [8] above, the statistic is preferably at least one of an average value and a standard deviation. The measured rail-to-ground voltage used in this system may vary due to non-essential causes. On the other hand, as a method of eliminating transient or sudden and trivial phenomena, it is preferable that the device calculates statistics such as the standard deviation and average value of the rail-to-ground voltage at each position for a predetermined period. .

[10] As shown in FIGS. 1, 8, 9 and 11, in the device of [4] above, first, the rail-to-ground voltage calculators 103 and 903 calculate Outputs the reference rail-to-ground voltage. The apparatus then compares the reference rail voltage to ground with the measured rail voltage to ground. As for the comparison result, it is preferable that the device has a function to start estimation of the ground resistance deterioration position triggered by deviation of the rail-to-ground voltage value and statistics at each position by a predetermined value or more.

It is preferable that such a device judges the extent to which the statistic is deviated with a threshold value and outputs a corresponding judgment result. For example, in FIG. 11, it can be estimated that the smaller the fluctuation range of the rail-to-ground voltage, the higher the possibility of the ground resistance deterioration position. As a result, this device can make appropriate judgments even when the positions and currents of the train and substation do not completely match the rail-to-ground voltage recorded when the ground resistance deteriorates.

In other words, if the device obtains a matching result that is close to some degree, it should output it as an estimated position. As a result, the present apparatus can eliminate the waste of continuing the search process until one that completely matches the actual measurement value is collated among many deteriorated samples. Therefore, the present apparatus can omit the burden of repeating unnecessary calculation processing in a simple computer having a program to be started as appropriate, and can estimate the ground resistance deterioration position with practical accuracy.

Such a present apparatus may be realized by using a single computer as the main part, or by using another computer in common. For example, it can be sufficiently put into practical use by using a part of the computer for the train operation control system as well. Therefore, the present apparatus requires less equipment.

101... Rail-to-ground voltage acquisition unit, 102... Position current acquisition unit, 103, 903... Rail-to-ground voltage calculation unit -ground voltage calculation unit), 104, 904 ... ground resistance deterioration position collation unit, 105 ... ground resistance deterioration position notification, 106 ... date and time Date and time designation part, 401: Up line, 402: Down line, 403: Crossing line, 410, 410a, 410b, 410c Rail resistance 420a, 420b Ground resistance 501 Rail direction resistance 502 Depth resistance 611 .. Low resistance, 801 Rail-to-ground voltage, 901 .. Rail-to-ground voltage acquisition unit, 902 .. Position current acquisition unit (Position current acquisition unit), 990... Grounding resistance deterioration position estimation start judgment unit, 1101... Rail-to-ground voltage measurement results, 1102, 1103 --- Rail-to-ground voltage measurement results when ground resistance deteriorates B

Claims (12)

A ground resistance deterioration position estimating device for estimating a ground resistance deterioration position in a target route,
a rail-to-ground voltage calculation unit for calculating rail-to-ground voltage candidate values for each of a plurality of positions based on predicted positions where there is a possibility of ground resistance deterioration, and storing the rail-to-ground voltage candidate values so that they can be output;
a rail-to-ground voltage acquisition unit that acquires measured rail-to-ground voltage values at a plurality of positions in the target line;
A ground resistance degradation position matching unit that selects the predicted position where a similar tendency is found based on the result of comparing and collating the rail-to-ground voltage actual value and the rail-to-ground voltage candidate value, and sets it as a ground resistance degradation position. and,
A ground resistance deterioration position estimation device. The ground resistance deterioration position matching unit
If there is an approximated tendency for the rail-to-ground voltage candidate values at each of the plurality of positions, the ground resistance of the proximity between the predicted positions across the plurality of positions is proportionally adjusted according to the degree of approximation of the tendency. degraded position,
The ground resistance deterioration position estimating device according to claim 1. further comprising a position current acquisition unit that acquires the position of the electric car on the line and the position of the power supply equipment on the target route and their currents at the same time as the acquisition of the measured rail-to-ground voltage value;
The ground resistance deterioration position estimating device according to claim 2. The rail-to-ground voltage calculation unit when the ground resistance deteriorates,
Create a ground resistance degradation return line resistance model by connecting a low resistance simulating ground resistance deterioration to a return line resistance model simulated by rail resistance and ground resistance,
Input the positions of the electric car and the substation at the time of obtaining the rail-to-ground voltage measurement value and their currents into the ground resistance deterioration return line resistance model to calculate the ground voltage across the rail resistance,
outputting the ground voltage as a rail-to-ground voltage candidate value when the ground resistance is degraded;
The ground resistance deterioration position estimating device according to claim 2. The rail-to-ground voltage calculation unit when the ground resistance deteriorates,
The ground resistance deterioration position when the ground resistance deterioration occurred on the target route in the past,
The rail-to-ground voltage measured values at multiple positions at that time are linked and stored,
Output as a rail-to-ground voltage candidate value when the ground resistance deteriorates,
The ground resistance deterioration position estimating device according to claim 1 or 4. The ground resistance deterioration position matching unit
By comparing the actual rail-to-ground voltage value at each position with the rail-to-ground voltage candidate value at the time of ground resistance deterioration,
Search for the rail-to-ground voltage at the time of ground resistance deterioration that is closest to the rail-to-ground voltage value at each position,
determining the ground resistance deterioration position when the rail-to-ground voltage at the time of the earth resistance deterioration is recorded or generated as the ground resistance deterioration position;
The ground resistance deterioration position estimating device according to claim 2. The rail-to-ground voltage calculation unit when the ground resistance deteriorates,
Under the condition that the position of the electric car and the power supply equipment and their current match within a predetermined range when the rail-to-ground voltage measurement value is obtained,
Selecting and outputting the rail-to-ground voltage at the time of earth resistance deterioration recorded in the state with earth resistance deterioration,
The ground resistance deterioration position estimating device according to claim 5. The ground resistance deterioration position matching unit
a statistic of the rail-to-ground voltage value at each location over a given period of time;
a statistic in a predetermined period of the rail-to-ground voltage when the ground resistance deteriorates;
to calculate
Search for the rail-to-ground voltage at the time of ground resistance deterioration that has the closest statistic at each position,
The ground resistance deterioration position when the rail-to-ground voltage is recorded or generated at the time of earth resistance deterioration,
Presumed to be the ground resistance deterioration position,
The ground resistance deterioration position estimating device according to claim 1. The statistic is at least one of the mean and standard deviation,
The ground resistance deterioration position estimation device according to claim 8. having a reference rail-to-ground voltage calculator that outputs a rail-to-ground voltage when no deterioration of the ground resistance occurs;
By comparing the measured rail-to-ground voltage with the reference rail-to-ground voltage,
If the rail-to-ground voltage value or statistics at each position deviates by a predetermined value or more,
Start the ground resistance deterioration position estimation,
The ground resistance deterioration position estimation device according to claim 4. A ground resistance deterioration position estimation method for estimating a ground resistance deterioration position in a target route,
storing a plurality of predicted positions where there is a possibility of ground resistance deterioration and rail-to-ground voltage candidate values corresponding to the predicted positions for each of the plurality of positions;
Acquiring actual rail-to-ground voltage values at the plurality of positions over a predetermined period of time,
comparing and collating the rail-to-ground voltage actual measurement value and the rail-to-ground voltage candidate value according to the tendency of the predetermined period;
The predicted position where a tendency similar to the result of the comparison and collation is found is set as the ground resistance deterioration position;
Ground resistance deterioration position estimation method. If there is an approximated tendency for the rail-to-ground voltage candidate values at each of the plurality of positions, the ground resistance of the proximity between the predicted positions across the plurality of positions is proportionally adjusted according to the degree of approximation of the tendency. degraded position,
The ground resistance deterioration position estimation method according to claim 11.

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