JP5319503B2 - AC AT feeder circuit protection device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a feeding protective technology for an alternating current AT feeding circuit that can surely detect a failure even in a long and large feeding section. <P>SOLUTION: A feeding protective device for the alternating current AT feeding circuit incorporates feeding voltage of both ends of a protective section at the respective electric power station ends, measures the incorporated feeding voltage in every optional period, integrally shares feeding voltage information of each end as the same time series voltage information by mutual high-speed communication, computes the same time series voltage information of both ends to obtain differential voltage time series information, carries out filtering operation of the differential voltage time series information to obtain time series information of differential voltage fundamental wave components, carries out amplitude value operation of the time series information of the differential voltage fundamental wave components to obtain a differential voltage fundamental wave component amount, and makes comparative determination of the differential voltage fundamental wave component amount and a predetermined constant to detect a section failure. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a feeder protection device and method for detecting a short circuit or a ground fault occurring in an AT section of an AC AT feeder circuit in an electric railway.

  An example of a general system configuration of an AT feeder circuit in an AC electric railway is shown in FIG. Along the railway, substations SS that supply feeder power are provided at intervals of several tens of kilometers, and both substation power sources are divided by feeder substations SP. Furthermore, an auxiliary feeder section SSP is provided for restricting the same power source section. Each substation and each feeder section has a self-transforming transformer AT. The operation method of switching the two-way power source in the switching section of the feeding section SP according to the train traveling position is called “matching power”, and the switching section of the feeding section SP is bypassed with a switch. The operation method of extending the power supply in the opposite direction is called “extension power”. There are two types of train lines: down line and up line. The upper and lower lines are fed from the substation to the upper and lower lines, and are separated or combined by the upper and lower line tie switches provided at the feeding section.

  As shown in FIG. 20, the AT feeder circuit is composed of a trolley wire T, a feeder wire F, a rail R, and a protective wire PW, and single-turn transformers AT are arranged at intervals of about 10 km. The feeding voltage V of the substation SS is stepped down (V / N) to the voltage between the trolley line T and the rail R at the turn ratio N of the autotransformer AT and supplied to the electric vehicle. The electric vehicle current flowing through the trolley wire T and the rail R is converted to a value 1 / N of the turn ratio multiplied by the autotransformer AT, and the electric wire F is fed back when the trolley wire T is passed to the power source V of the substation SS.

  FIG. 21 shows the line short-circuit impedance of a general train line detected at the substation SS. Although the TF short-circuit impedance is linear with respect to the line length, the T-R short circuit, the T-PW short circuit, the F-PW short circuit, and the ground faults of T and F (not shown) are crossed between the rail R and the protection line PW. The point CPW bulges upward at a node. As a feeder system protection method, a distance relay (# 44F) having a fault detection area having a parallelogram shape has been generally used so as to cover the impedance characteristics of such an AT feeder circuit. . FIG. 22 shows an example of the characteristics.

  In addition to this distance relay, an AC ΔI type relay (# 50F) that detects a failure from a steep change in feeding current is used, and is used together with the distance relay # 44F to detect a failure in the feeding circuit. FIG. 23 shows an example of the characteristics. These # 44F and # 50F are installed not only at the power source substation SS, but also at each power station located on the train line of the feeder section SP and auxiliary feeder section SSP. It is configured such that a fault can be detected at least at an electric station near the fault point against a fault current that changes in distribution. An arrangement example of these protection elements (# 44F, # 50F) is shown in FIG. FIG. 24 is an arrangement example between the A substation Ass and the B substation Bss.

  Such a conventional AT feeder circuit has the following problems. Each of the upper and lower lines of a railway feeder circuit train line is roughly divided into a feeder section composed of a train line such as a trolley line T, a feeder line F, a rail R, a protection line PW, etc. The feeder posts SS, SSP, and SP are coupled or separated by a switch. However, T, F ground faults, T-R, T-PW, FR, F-PW short-circuit faults, and TF short-circuit faults occur at various locations.

  On the other hand, the load current of the electric vehicle fluctuates in accordance with the traveling state, and the electric vehicle current entering the feeding section is caused by an excessive inrush current of the vehicle transformer, resulting in a sharp increase in current. In addition, the feeder circuit is equipped with a reclosing function, and at the time of reclosing, a plurality of electric vehicles in the feeding section and a plurality of autotransformers AT are re-pressurized all at once, resulting in excessive inrush current of the transformer. Will occur. The protection relay provided in the feeder circuit is required to have a capability of reliably discriminating between such load current fluctuation and fault current. However, if the interval between substations becomes longer due to the construction of the substation, the number of electric cars in the line increases, so the load current increases, and the fault current decreases as the line constant increases as the line length increases. For this reason, like the overlapping portion shown in the current example of FIG. 25, the load current and the fault current region are close to each other or overlapped, which may make it difficult to detect the far-end fault. In the current example of FIG. 25, it is difficult to detect a failure in a region where the maximum load current exceeds the TR (trolley wire-rail) failure current.

JP 2008-221898 A JP 2004-74924 A JP 2003-2088 A

  The present invention has been made in view of the above-described problems of the prior art, and provides a feeder protection device and method for an AC AT feeder circuit that can reliably detect a failure even in a long feeder section. Objective.

  One feature of the present invention is a feeder protection device that detects a failure of a train line that is bounded by a transformer of an electric power station arranged at an arbitrary distance section in an AC transformer transformer feeder circuit. The feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end, and the feeding voltage captured at each of the electrical station ends is measured at each arbitrary period. A voltage information terminal means for performing high-speed communication with each other and sharing the feeding voltage information at each end as the same time-series voltage information at both ends; and calculating the same time-series voltage information at both ends and calculating the difference voltage time-series information Difference voltage time series information calculating means for obtaining difference voltage fundamental wave component calculating means for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component, and the difference voltage fundamental wave component Calculate the amplitude value of time series information A difference voltage fundamental wave component amount calculating means for obtaining a voltage fundamental wave component amount, and a voltage base section failure detecting means for detecting a section failure by comparing and determining the difference voltage fundamental wave component amount and a predetermined constant. It is in.

  Another feature of the present invention is a feeder protection device for detecting a failure of a train line bordered by a transformer of an electric power station arranged at an arbitrary distance section in an AC transformer transformer feeder circuit. In addition, the feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at the respective electrical station ends, and the feeding voltage captured at each of the electrical station ends is measured for each arbitrary period. A voltage information terminal means for sharing the voltage information at each end as the same time-series voltage information at both ends by performing high-speed communication with each other, and calculating the same time-series voltage information at both ends to calculate a difference voltage time series Difference voltage time series information calculating means for obtaining information, difference voltage fundamental wave component calculating means for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and the difference voltage fundamental wave component The time series information of A differential voltage fundamental wave component amount calculating means for obtaining a differential voltage fundamental wave component amount; and a train line current obtaining means for capturing the both-end train line current of the protection section from the secondary side of the current transformer at each electric station end; , Current information terminal means for measuring the train line current captured at each end of the electric station for each arbitrary period, and mutually sharing the train line current at each end as the same time-series current information at high speed by mutual communication, Difference current calculation means for calculating difference current time series information by calculating the same time series current information at both ends, and difference current for calculating time series information of the difference current fundamental wave component by filtering the difference current time series information Fundamental wave component calculating means; differential current fundamental wave component amount calculating means for calculating a difference current fundamental wave component amount by calculating an amplitude value of time series information of the differential current fundamental wave component; and Constants Compare the determined said difference current fundamental wave component amount and determining comparing the predetermined constant, lies in that a segment fault detection means for detecting a duration fault from the both determination results.

  Another feature of the present invention is a feeder protection device for detecting a failure of a train line bordered by a transformer of an electric power station arranged at an arbitrary distance section in an AC transformer transformer feeder circuit. In addition, the feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at the respective electrical station ends, and the feeding voltage captured at each of the electrical station ends is measured for each arbitrary period. A voltage information terminal means for sharing the voltage information at each end as the same time-series voltage information at both ends by performing high-speed communication with each other, and calculating the same time-series voltage information at both ends to calculate a difference voltage time series Difference voltage time series information calculating means for obtaining information, difference voltage fundamental wave component calculating means for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and the difference voltage fundamental wave component The time series information of A differential voltage fundamental wave component amount calculating means for obtaining a differential voltage fundamental wave component amount; and a train line current obtaining means for capturing the both-end train line current of the protection section from the secondary side of the current transformer at each electric station end; , Current information terminal means for measuring the train line current captured at each end of the electric station for each arbitrary period, and mutually sharing the train line current at each end as the same time-series current information at high speed by mutual communication, Difference current calculation means for calculating difference current time series information by calculating the same time series current information at both ends, and difference current for calculating time series information of the difference current fundamental wave component by filtering the difference current time series information Fundamental wave component calculating means, difference current fundamental wave component amount calculating means for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component, and the same time series current information at both ends. Calculate each end Current time series information calculating means for obtaining current time series information, fundamental wave current time series information calculating means for filtering the current time series information at each end to obtain fundamental wave current time series information at each end, and each of the above Fundamental wave current component amount calculating means for calculating the fundamental wave current component amount at each end by calculating the amplitude value of the fundamental wave current time-series information at the end, and the difference current fundamental wave component amount and the fundamental wave current component amount at each end The section passage current amount calculation means for obtaining the section passage current amount from the above, and the section passage current amount equivalent to obtain the section inflow current amount equivalent difference voltage by multiplying the section passage current amount by a predetermined line constant and subtracting from the difference voltage fundamental wave component amount A difference voltage calculation means, and a section failure detection means for comparing and determining the section inflow current amount equivalent difference voltage and a predetermined constant to detect a section failure are provided.

  Another feature of the present invention is a feeder protection device for detecting a failure of a train line bordered by a transformer of an electric power station arranged at an arbitrary distance section in an AC transformer transformer feeder circuit. In addition, the feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at the respective electrical station ends, and the feeding voltage captured at each of the electrical station ends is measured for each arbitrary period. A voltage information terminal means for sharing the voltage information at each end as the same time-series voltage information at both ends by performing high-speed communication with each other, and calculating the same time-series voltage information at both ends to calculate a difference voltage time series Difference voltage time series information calculating means for obtaining information, difference voltage fundamental wave component calculating means for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and the difference voltage fundamental wave component The time series information of A difference voltage fundamental wave component amount calculating means for obtaining a difference voltage fundamental wave component amount; a voltage base interval failure detecting means for comparing and determining the difference voltage fundamental wave component amount and a predetermined constant to detect an interval failure; and the difference Second harmonic time series information calculating means for obtaining the second harmonic time series information of the difference voltage by filtering the voltage time series information, and calculating the amplitude value of the second harmonic time series information of the difference voltage and calculating the difference voltage Difference voltage second harmonic component amount calculating means for calculating the second harmonic component amount, and the second harmonic of the difference voltage from the ratio calculation of the difference voltage second harmonic component amount and the difference voltage fundamental wave component amount A second harmonic content calculating means for calculating the content, the second harmonic content is compared with a predetermined determination constant, and the second harmonic content exceeds a predetermined determination constant. Section fault judgment by the voltage base section fault detection means It lies in that a section failure determination inhibition means for inhibiting.

  Another feature of the present invention is a feeder protection device for detecting a failure of a train line bordered by a transformer of an electric power station arranged at an arbitrary distance section in an AC transformer transformer feeder circuit. In addition, the feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at the respective electrical station ends, and the feeding voltage captured at each of the electrical station ends is measured for each arbitrary period. Voltage information terminal means for mutually sharing high-speed communication with each other and feeding voltage information at each end as the same time-series voltage information at both ends, and measuring the electric current at both ends of the protection section at each electric station end Measures the train line current acquisition means that captures from the secondary side of the current transformer and the train line current that is captured at each end of the electrical station, and communicates at high speed with each other to communicate the train line current at each end at both ends. As the same time series current information Current information terminal means for calculating the difference current time series information by calculating the same time series current information at both ends, filtering the difference current time series information, and calculating the difference current fundamental wave component Difference current fundamental wave component calculation means for obtaining time series information, difference current fundamental wave component amount calculation means for calculating an amplitude value of time series information of the difference current fundamental wave component to obtain a difference current fundamental wave component amount, and the difference Current base section fault detection means for detecting section faults by comparing and determining a current fundamental wave component amount and a predetermined constant, and obtaining voltage time series information at each end from the same time series voltage information at both ends of the protection section Voltage time-series information calculating means, voltage basic time-series information calculating means for obtaining fundamental wave time-series information of the voltage at each end by filtering the voltage time-series information at each end, and basic voltage of each end Wave time Voltage fundamental wave component amount calculating means for calculating the amplitude value of the column information to obtain the voltage fundamental wave component amount at each end, and the voltage change amount between the past value and the current value of the voltage fundamental wave component amount at each end. A voltage change amount calculating means to be obtained every time, a voltage change amount calculating means to obtain a scalar sum by adding the voltage change amounts at each end, and comparing and determining the difference current fundamental wave component amount and a predetermined constant. And a section failure detecting means for comparing and determining a scalar sum of the voltage change amount and a predetermined constant and detecting a section failure from both determination results.

  Another feature of the present invention is a feeding protection method for detecting a failure of a train line bordering on a winding transformer of an electric station arranged for each arbitrary distance section in an AC winding transformer feeding circuit. In addition, the feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end, and the feeding voltage captured at each of the electrical station ends is measured at each arbitrary period A voltage information sharing step for mutually sharing high-speed communication with each other and feeding voltage information at each end as the same time-series voltage information at both ends; and calculating a difference voltage time-series by calculating the same time-series voltage information at both ends A difference voltage calculation step for obtaining information, a difference voltage fundamental wave component calculation step for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and a time series of the difference voltage fundamental wave component Information amplitude value A difference voltage fundamental wave component amount calculating step for calculating a difference voltage fundamental wave component amount, and a voltage base interval failure detecting step for comparing and determining the difference voltage fundamental wave component amount and a predetermined constant to detect an interval failure; It is in that it has.

  Another feature of the present invention is a feeding protection method for detecting a failure of a train line bordering on a winding transformer of an electric station arranged for each arbitrary distance section in an AC winding transformer feeding circuit. In addition, the feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end, and the feeding voltage captured at each of the electrical station ends is measured at each arbitrary period A voltage information sharing step for mutually sharing high-speed communication with each other and feeding voltage information at each end as the same time-series voltage information at both ends; and calculating a difference voltage time-series by calculating the same time-series voltage information at both ends A difference voltage calculation step for obtaining information, a difference voltage fundamental wave component calculation step for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and a time series of the difference voltage fundamental wave component Information amplitude value Step of calculating the difference voltage fundamental wave component amount by calculating the difference voltage fundamental wave component amount, and the train line current that takes in both ends of the protection section from the secondary side of the current transformer at each electrical station end Current information sharing in which the electric line current taken at each end of the electric station is measured at an arbitrary period, and the electric line current at each end is centrally shared as the same time-series current information at both ends by obtaining high-speed communication with each other Calculating a difference current time-series information by calculating the same time-series current information at both ends, and filtering the difference current time-series information to obtain time-series information of the difference current fundamental wave component A difference current fundamental wave component calculating step, a difference current fundamental wave component amount calculating step for calculating a difference current fundamental wave component amount by calculating an amplitude value of time series information of the difference current fundamental wave component, and the difference voltage base A section failure detection step of comparing and determining a wave component amount and a predetermined constant, comparing and determining the difference current fundamental wave component amount and a predetermined constant, and detecting a section failure from both determination results It is in.

  Another feature of the present invention is a feeding protection method for detecting a failure of a train line bordering on a winding transformer of an electric station arranged for each arbitrary distance section in an AC winding transformer feeding circuit. In addition, the feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end, and the feeding voltage captured at each of the electrical station ends is measured at each arbitrary period A voltage information sharing step for mutually sharing high-speed communication with each other and feeding voltage information at each end as the same time-series voltage information at both ends; and calculating a difference voltage time-series by calculating the same time-series voltage information at both ends A difference voltage calculation step for obtaining information, a difference voltage fundamental wave component calculation step for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and a time series of the difference voltage fundamental wave component Information amplitude value Step of calculating the difference voltage fundamental wave component amount by calculating the difference voltage fundamental wave component amount, and the train line current that takes in both ends of the protection section from the secondary side of the current transformer at each electrical station end Current information sharing in which the electric line current taken at each end of the electric station is measured at an arbitrary period, and the electric line current at each end is centrally shared as the same time-series current information at both ends by obtaining high-speed communication with each other Calculating a difference current time-series information by calculating the same time-series current information at both ends, and filtering the difference current time-series information to obtain time-series information of the difference current fundamental wave component A difference current fundamental wave component calculation step to obtain; a difference current fundamental wave component amount calculation step to obtain a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component; Current time series information calculation step for calculating current time series information at each end by calculating time series current information, and a basic operation for obtaining fundamental wave current time series information at each end by filtering the current time series information at each end A wave current time series information calculation step, a fundamental wave current component amount calculation step for calculating a fundamental wave current component amount at each end by calculating an amplitude value of the fundamental wave current time series information at each end, and the difference current fundamental wave A section passing current amount calculating step for obtaining a section passing current amount from the component amount and the fundamental current component amount at each end, and multiplying the section passing current amount by a predetermined line constant, and subtracting from the difference voltage fundamental wave component amount. The equivalent difference voltage calculation step for obtaining the section inflow current amount equivalent difference voltage, and the section failure detection step for comparing and determining the section inflow current amount equivalent difference voltage and a predetermined constant to detect a section failure. The

  Another feature of the present invention is a feeding protection method for detecting a failure of a train line bordering on a winding transformer of an electric station arranged for each arbitrary distance section in an AC winding transformer feeding circuit. In addition, the feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end, and the feeding voltage captured at each of the electrical station ends is measured at each arbitrary period A voltage information sharing step for mutually sharing high-speed communication with each other and feeding voltage information at each end as the same time-series voltage information at both ends; and calculating a difference voltage time-series by calculating the same time-series voltage information at both ends A difference voltage calculation step for obtaining information, a difference voltage fundamental wave component calculation step for obtaining time series information of the difference voltage fundamental wave component by filtering the difference voltage time series information, and a time series of the difference voltage fundamental wave component Information amplitude value A difference voltage fundamental wave component amount calculating step for calculating a difference voltage fundamental wave component amount, and a voltage base interval failure detecting step for comparing and determining the difference voltage fundamental wave component amount and a predetermined constant to detect an interval failure; A second harmonic time series information calculation step for obtaining the second harmonic time series information of the difference voltage by filtering the difference voltage time series information, and calculating an amplitude value of the second harmonic time series information of the difference voltage. Differential voltage second harmonic component amount calculating step for calculating the difference voltage second harmonic component amount, and calculating the difference voltage from the difference voltage second harmonic component amount and the difference voltage fundamental wave component amount. The second harmonic content calculating step for calculating the second harmonic content and the second harmonic content are compared with a predetermined determination constant, and the second harmonic content exceeds the predetermined determination constant. When the voltage base interval is In that it has a section failure determination inhibiting step of inhibiting the section failure determination by the detecting step.

  Furthermore, another feature of the present invention is a feeder protection method for detecting a failure of a train line bordering on a transformer of an electric power station arranged at an arbitrary distance section in an AC transformer transformer feeder circuit. In addition, the feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end, and the feeding voltage captured at each of the electrical station ends is measured at each arbitrary period A voltage information sharing step for mutually sharing high-speed communication with each other and feeding voltage information at each end as the same time-series voltage information at both ends, and measuring the electric current at both ends of the protection section at each electric station end. The electric line current acquisition step to be taken in from the secondary side of the current transformer and the electric line current to be taken in at each end of the electric station are measured every arbitrary period, and the electric line current at each end is measured at both ends by high-speed communication with each other Same time series current information A current information sharing step that is shared as a unit, a difference current calculation step that calculates the same time-series current information at both ends to obtain difference current time-series information, and a filtering operation on the difference-current time-series information to calculate a difference current basic A difference current fundamental wave component calculation step for obtaining time series information of the wave component; a difference current fundamental wave component amount calculation step for calculating an amplitude value of the time series information of the difference current fundamental wave component to obtain a difference current fundamental wave component amount; A current base section failure detection step for comparing and determining the difference current fundamental wave component amount and a predetermined constant to detect a section failure; and voltage time series at each end from the same time series voltage information at both ends of the protection section A voltage time-series information calculating step for obtaining information; and a voltage fundamental wave time-series information for obtaining fundamental wave time-series information of the voltage at each end by filtering the voltage time-series information at each end. A voltage fundamental wave component amount calculating step for calculating a voltage fundamental wave component amount at each end by calculating an amplitude value of the fundamental wave time-series information of the voltage at each end, and a voltage fundamental wave component amount at each end. A voltage change amount calculating step for obtaining a voltage change amount between a past value and a current value for each end; a voltage change amount calculating step for obtaining a scalar sum by adding the voltage change amounts for each end; and the difference current A section failure detection step of comparing and determining a fundamental wave component amount and a predetermined constant, comparing and determining a scalar sum of the voltage change amount and a predetermined constant, and detecting a section failure from both determination results It is in.

  According to the feeder protection device and method of the AC AT feeder circuit of the present invention, the selectivity of fault detection for the area where the load current and the fault current approach in the protection section is improved, and the conventional protection equipment provided at both ends of the protection section is provided. The number of protection elements can be halved.

  Further, according to the feeder protection device and method of the AC AT feeder circuit of the present invention, it is possible to suppress unnecessary operation due to the differential voltage generated by the passing current to the outside of the protection section, and at the same time, the secondary transformer of the instrument transformer It is also possible to suppress unnecessary operations due to the differential voltage caused by voltage introduction failure.

  In addition, according to the feeder protection device and method of the AC AT feeder circuit of the present invention, the differential voltage detection sensitivity in the protection section can be remarkably improved.

  Furthermore, according to the feeder protection device and method of the AC AT feeder circuit of the present invention, the difference voltage detection sensitivity in the protection section can be remarkably improved, and at the same time, due to the difference voltage caused by the poor introduction of the secondary voltage of the instrument transformer. Unnecessary operations can also be suppressed.

The circuit diagram which shows the basic composition of a general alternating current AT feeder circuit. FIGS. 2A (a) and 2 (b) are diagrams for explaining the feeding protection operation in the differential voltage protection method by the feeding protection device and method of the present invention, and show the principle of detecting a short-circuit fault between the trolley wire and the rail. Illustration. FIGS. 2B (a) and 2 (b) are diagrams for explaining the feeding protection operation in the differential voltage protection method by the feeding protection device and method of the present invention, and show the principle of detection of a short-circuit fault in a trolley wire. Illustration. 1 is a block diagram of a feeding protection device according to a first embodiment of the present invention. In the said 1st Embodiment, explanatory drawing which shows the load current outside a zone, and the difference voltage of a protection zone. The block diagram of the electricity protection apparatus of the 2nd Embodiment of this invention. The graph which shows the time change characteristic of the position movement of an electric vehicle, and an electric current increase in the said embodiment. Explanatory drawing of the feeding protection operation | movement by the differential voltage protection system by the feeding protection apparatus of the 3rd Embodiment of this invention. The block diagram of the feeding protection apparatus of the said 3rd Embodiment. The block diagram of the electricity protection apparatus of the 4th Embodiment of this invention. Explanatory drawing of the electric vehicle inrush current which flows into a protection area in relation to the feeding protection apparatus of the 5th Embodiment of this invention. The measurement waveform figure of the section both-ends differential voltage in the electric vehicle repressurization in relation to the fifth embodiment. The block diagram of the feeding protection apparatus of the said 5th Embodiment. The circuit diagram which shows the difference of the electric current distribution change of the train line before a failure, and the difference voltage of both ends of a protection area in connection with the 6th Embodiment of this invention. The circuit diagram which shows the current distribution change of the train line at the time of a failure, and the difference voltage of both ends of a protection area in relation to the said 6th Embodiment. The equivalent circuit schematic of the electric current superimposition inside and outside a protection area in relation to the said 6th Embodiment. The block diagram of the feeding protection apparatus of the said 6th Embodiment. The graph which shows the voltage change according to the position of the electric current in the protection area before a failure, and the failure point of a failure current in relation to the said 6th Embodiment. Explanatory drawing of the amount of fault electricity which flows in a protection area in relation to the said 6th Embodiment. Explanatory drawing of the feeding protection system of a prior art example. Explanatory drawing of the differential voltage protection system by the 1st Embodiment of this invention. The graph which shows the variation | change_quantity of the terminal voltage difference before and behind failure by the 2nd Embodiment of this invention, and the difference voltage at the time of failure. The circuit diagram which shows the structure of the conventional alternating current AT feeder circuit. Explanatory drawing which shows the principle of alternating current AT feeding. The graph of the distance-impedance characteristic of an AC AT feeder circuit. The graph of the operating characteristic of the conventional distance relay (# 44F). The graph of the operating characteristic of the conventional AC ΔI type relay (# 50F). The circuit diagram which shows the arrangement | positioning of the feeder system and protection relay element (# 44F, # 50F) in the conventional alternating current AT feeder circuit. It is a graph for demonstrating the subject of the feeding protection apparatus of the conventional alternating current AT feeding circuit, Comprising: The graph which shows the relationship between a load current and a short circuit fault current.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 shows a general system configuration example of an AT feeder circuit in an AC electric railway, which is the same as the configuration of FIG. 19 described above in the conventional example. 2A (a) and 2B (a) show, as a representative example, the down line of an arbitrary section in a plurality of AT sections of the system configuration described above with reference to FIG. 1 in order to explain the principle of differential voltage protection according to the present invention. Therefore, both ends of the protection section are respectively connected to the autotransformers AT of the electric stations A and B, and the train lines in the protection section are indicated by three types of trolley lines, rails, and feeders. FIG. 2A (a) shows a short circuit failure between the trolley wire and the rail at an indefinite position d in the protection section, and FIG. 2A (b) is a fault equivalent circuit thereof. FIG. 2B (a) shows a short circuit failure of the electric wire when the trolley wire is used, and FIG. 2B (b) is also a fault equivalent circuit thereof. A fault occurring at an indefinite position d in the section with the train line impedance ZL of the entire protection section as a reference value 1PU is accompanied by a fault point impedance ZF, and a fault current I flows. The fault current I is a branch point of the impedance ZA and ZB where the train line impedance ZL of the protection section is divided into two at the fault point d, and the currents IA and IB branch and flow to the electric stations A and B at the ends, respectively.

  The electric power stations A and B at both ends of the section are provided with protective devices 1A and 1B, respectively, and feed voltages VA and VB at the ends are introduced through instrument transformers (not shown). The protection devices 1A and 1B at both ends of the section communicate the feeding voltages VA and VB measured in sampling synchronization every arbitrary period at high speed, and store and update the same time-series information as many times as desired. The protection devices 1A and 1B at both ends of the section obtain the fundamental wave component amount of the difference dV between the both-end voltages VA and VB by performing filtering calculation and amplitude calculation on the sampling time series information of the feeding voltage at both ends to be stored and updated. Detecting section faults. 2A (a) and FIG. 2B (a) consolidate train line impedances of rails and electric wires into trolley line impedances ZA, ZB, ZL in order to simplify the principle description.

2A (a) trolley wire and rail short circuit failure, in the fault equivalent circuit of FIG. 2A (b), the power supply voltage is V, the transformer ratio of the autotransformer AT at both ends of the protection section is N, the power supply to the protection section The path impedance is ZP, the line impedance of the entire protection section is ZL, the AT leakage impedance is ZAT, the failure point resistance is Zf, the ratio of the AT leakage impedance ZAT to the line impedance ZL is kZAT, and the line impedance ZA from the electric station A to the failure point The ratio of the line length to the protection section line length ZL is d, the line length ratio of the line impedance ZB from the failure point to the electric station B is 1-d, and the current flowing from the electric line at the electric station A end to the failure point is IA, If the current flowing from the train line at the end of the station B to the failure point is IB, the voltages at both ends of the section are VA, VB, and the differential voltage at both ends of the section is dV, these are The relationship of the equations 1 to 4 are satisfied.

However, α is a coupling function of upper and lower lines at the electric power stations A and B at both ends of the section, (α = 1) when the upper and lower lines are open, and (α = 2) when coupled.

Here, if the turn ratio N of the autotransformer AT is 2, and the leakage impedance ZAT of the autotransformer AT with respect to the line impedance ZL in the long distance section is small and ignored (ZAT = 0), it corresponds to the failure point ratio d. The differential voltage dV at both ends of the section is the formula of Formula 5, Formula 6 when the vertical lines at both ends of the section are open (α = 1), Formula 6a when the vertical lines at both ends of the section are coupled (α = 2) ) Value.

  Similarly, in the case of the trolley wire of FIG. 2B (a) and FIG.

However, β is a coupling function of the upper and lower lines at the electric power stations A and B at both ends of the section. When the upper and lower lines are open (β = ∞), in the coupling (β = 1)

Here, the differential voltage at both ends of the section generated according to the failure point ratio d is expressed by Equation 11 (β = ∞) when the upper and lower lines at both ends of the section are open, and Equation 12 when the upper and lower lines at both ends of the section are combined. The value is (β = 1).

  As can be understood from the above-described equation (4) for the trolley wire and rail short-circuit failure in FIG. 2A (a) and equation (10) for the trolley wire and wire short-circuit failure in FIG. This is a principle expression using a failure point d and a failure current I flowing into the section as a function with reference to the full-length train line impedance ZL.

  Moreover, the trolley wire and rail short-circuit fault current in FIG. 2A (a) is a current based on the train line voltage V / N (Equation 4). When the trolley wire in FIG. This is the electric voltage V reference (Equation 10). However, the trolley wire and rail short circuit, the trolley wire and the wire short circuit, and the differential voltage dV across the section at the same failure point d of both of them is more than about 0.2 PU when the trolley wire and the wire short circuit failure, and the failure point is far from the power source. It increases as much.

  Further, the rate of change of the differential voltage amount dV when the upper and lower lines of both ends of the electrical stations A and B are coupled and opened is 50% for both.

  FIG. 3 shows a section difference voltage method calculation method by the feeder protection device 1 according to the first embodiment of the present invention. The feeder protection device 1 is the protection devices 1A and 1B at both ends of the protection section shown in FIGS. 2A (a) and 2B (a). The configuration of both-end protection devices 1A and 1B is the same. As described with reference to FIGS. 2A (a) and 2B (a), the both-end protection devices 1A and 1B communicate with each other voltage information measured at both ends in a sampling-synchronized manner, and an arbitrary number of samplings can be obtained. Are stored as the same time-series information VA and VB, and updated each time. The means relating to sampling synchronous measurement, mutual communication, and storage update of sampling time series information are already publicized and put into practical use.

  In the differential voltage time-series information calculation step, the differential voltage time-series information calculation unit 11 stores the difference between the sampling values at the same time of the both-end voltage information as the both-end difference voltage time-series information dV for an arbitrary number of samplings, and updates it whenever necessary. .

  In the differential voltage fundamental wave component computation step, the differential voltage fundamental wave component computation unit 12 performs filtering computation on the differential voltage time-series information at both ends, and time-series information for the fundamental wave components of the differential voltages VA and VB at any sampling times. And update as needed.

  In the difference voltage amount calculation step, the difference voltage amount calculation unit 13 calculates the amplitude value of the fundamental wave component time-series information of the difference voltage at both ends to obtain the difference voltage amount | dV |

  In the voltage base section failure detection step, the voltage base section failure detection unit 14 compares and determines the difference voltage amount | dV | at both ends of the section obtained by calculating the amplitude value and a predetermined failure determination value kV to determine the section failure. To detect. If | dV | ≧ kV, it is determined that there is a section failure. Otherwise, it is determined that there is no section failure.

  As described above, in the feeder protection device and method of the present embodiment, both-end protection devices 1A and 1B in the protection section have feeding voltage information at their ends via the instrument transformer VT connected to the train line. Are measured in synchronization with each other at sampling intervals and communicated with each other, and measurement information at both ends is stored as time-series information corresponding to the number of samplings, and updated at each sampling cycle. Then, the time series information of the differential voltage at both ends is generated by synthesizing the simultaneous series information of the both-end feeding voltage to be stored and updated for each sampling period, and the fundamental voltage difference between both ends calculated from the difference voltage time series information is calculated. A section failure is detected by comparison with the failure determination value.

  Thereby, the feeder protection apparatus and method of this Embodiment have the following effects.

  1) The failure detection selectivity for the region where the load current and the fault current are close to each other is improved.

  FIG. 16 (a) shows that a plurality of trains (1, 2,..., N) of electric vehicles travel on a train line in a protected section at equal intervals (d = 1 / n) at a constant, the same speed, and the same current IL. Then, it is a conceptual diagram. FIG. 5B shows a fault current If that flows to a fault point df at an indefinite position in the same protection section.

  In the conceptual diagram of steady load running and failure shown in FIGS. 16 (a) and 16 (b), the conventional protection method uses the maximum load current flowing in the protection section in order to avoid unnecessary operation in steady load running, that is, The fault current If (> n · IL) exceeding the load current IL per unit train n × the unit train is detected, or the fault impedance Zf below the train line impedance ZL of the entire section is detected. That is, it is difficult to detect a failure approaching the maximum load region.

On the other hand, in the differential voltage protection method according to the present embodiment, in FIGS. 16A and 16B, the maximum differential voltage dVL generated at both ends of the section during steady load traveling is a value of Formula 13 (d = 1 PU). . The difference voltage generated at both ends of the section due to the failure in the protection section is dVf having the value of the formula (14). Here, if the ratio kf = If / IL of the fault current If with respect to the load current IL per electric vehicle unit train is set, the fault point position df in which the differential voltage dVf at the time of failure exceeds the differential voltage dVL at the time of steady running is As shown in Equation 15, it can be expressed by a functional equation of the number n of electric vehicle formations and the failure current ratio Kf with respect to the load current. If the ratio kf of the fault current If to be detected to the load current IL per electric vehicle unit train is “4” and the number n of trains traveling in the section is “4”, it is difficult to protect the conventional system. Failure detection can be performed. In the case shown in the figure, it is possible to detect an area fault farther than 5/8 of the entire section length.

  2) The number of conventional protection elements provided at both ends of the section can be halved.

  As is clear from the comparison between the conventional method shown in FIG. 17A and the differential voltage method according to the present embodiment shown in FIG. 17B, the conventional protection elements provided at both ends of the section to be protected are integrated into the section differential voltage protection and simplified. (Halved).

[Second Embodiment]
In the first embodiment, the difference voltage dV generated at both ends of the section depends on the position d and the amount I of the current flowing into the section, as is apparent from the basic equations (4) and (10). As shown in FIG. 4, it is affected by the electric vehicle load current σIX = IX1 + IX2 + IX3 passing through the protection zone ZL = 1PU and flowing outside the protection zone. The influence increases as the section closer to the power source increases because the load current amount σIx passing through the section increases. However, the difference voltage dV at both ends of the section is the electric current that passes outside the protection section according to the basic principle expression (formula 4) of the current I flowing into the section described in FIG. 2A (a) and the difference voltage dV generated at the position d. The difference voltage due to the vehicle current σIx is superimposed. Here, if the turn ratio N of the autotransformer AT is 2 and the leakage impedance is ignored (ZAT = 0), it corresponds to the current ratio I and position d of the electric vehicle traveling in the section and the out-of-section passing current σIX. The difference voltage dV at both ends of the section is the value of the equation (16).

  However, α is a coupling function of upper and lower lines, and is open (α = 1), coupling (α = 2), kα: a difference voltage amount coefficient of a basic principle equation corresponding to an upper and lower line coupling state, and is opened (kα = 0. 4) A bond (kα = 0.22).

  FIG. 5 shows a configuration of the calculation function of the section difference voltage method by the feeder protection device 1 according to the second embodiment of the present invention. Elements of the same reference numerals as those in FIG. 3, that is, the difference voltage time series information calculation unit 11, the difference voltage fundamental wave component calculation unit 12, and the voltage base section failure detection unit 14 are the same as those in the first embodiment. Since the same processing is performed in steps, the description thereof is omitted.

The difference voltage amount calculation unit 13 in FIG. 3 calculates the amplitude value of the fundamental wave component time-series information of the differential voltage at both ends to obtain the difference voltage amount | dV | In the embodiment, in the differential voltage amount calculation step, the fundamental voltage component time series information of the differential voltage at both ends output by the differential voltage amount calculation unit 13a in the differential voltage fundamental wave component calculation step by the differential voltage fundamental wave component calculation unit 12 is obtained. The amplitude value is calculated, and a change ΔdV between the past t−n for an arbitrary cycle and the difference voltage | dV | t−n, | dV | t−0 at both ends of the current t−0 is obtained as shown in Equation 17.

Here, if the increase time constant dI / dt = dti of the electric vehicle maximum current traveling in the section is 1 sec, the power supply frequency f is 60 Hz, and the blind time w for detecting the amount of change is 5 cycles, as shown in FIG. The maximum vehicle load current is suppressed to a variation of about 5%. Further, if the traveling speed at a constant time of the electric vehicle traveling in the protection section is set to Skm / h and the acceleration time constant dtv, the section both-ends voltage dVt at the arbitrary time t is a value of Expression 18.

Here, as an example in which the difference voltage change ΔdV between the two ends of the section that occurs in the steady load traveling state is maximized, the number of electric vehicles at any position in the section is 1, the number of electric cars at any position outside the section is n, Assuming that the electric cars are simultaneously accelerating to the maximum current I and the protection section long distance is Lkm and the line impedance is ZL, the value of Equation 19 is obtained. In general, since the protection section long distance is 10 km or more, the amount of change in position movement due to the traveling speed of the electric vehicle is negligible and can be ignored, so it is certain that the section differential voltage dV is reduced to 10% or less.

  However, α is a coupling function of upper and lower lines, and is open (α = 1), coupling (α = 2), kα: a difference voltage amount coefficient of a basic principle equation corresponding to an upper and lower line coupling state, and is opened (kα = 0. 4) A bond (kα = 0.22).

  As described above, the feeder protection device and method according to the present embodiment are configured so that the protection devices 1A and 1B at both ends determine the increase amount of the current time point with respect to the past time point of the differential voltage obtained in the first embodiment. Detect failure.

  Thereby, according to the feeder protection apparatus and method of this Embodiment, there exist the following effects.

  1) The difference voltage detection sensitivity in the protection section can be remarkably improved.

In the feeder protection device and method of the present embodiment, the difference voltage amount in the section is detected by reducing it to the change amount between the past and the present. Therefore, the current of the electric vehicle that flows through the protection section and flows to other sections in the distance, the current and the travel position of the electric vehicle that travels in the protection section, and the ratio of the change detection time window width to the time constant of these electric vehicle travel changes Thus, the amount of change in the differential voltage can be reduced to the value of equation (19). That is, since the difference voltage at both ends of the section that occurs in steady load traveling is suppressed to a change amount of 10% or less, 10% or more of the maximum difference voltage that occurs at both ends of the section during steady load traveling can be set as the detected amount of difference voltage protection. In addition, when a failure occurs in the protection section, the failure current amount If and the current position df change sharply, so that the suppression of the change amount due to the window width ratio of the change detection time can be ignored. Therefore, as the difference voltage change amount at the time of failure, the difference between the difference voltage amounts before and after the failure, that is, the change amount ΔdVf of Expression 20 is detected.

  However, α is a coupling function of upper and lower lines, and is open (α = 1), coupling (α = 2), kα: a difference voltage amount coefficient of a basic principle equation corresponding to an upper and lower line coupling state, and is opened (kα = 0. 4), coupling (kα = 0.22), df: failure current position, If: failure current amount, d: section travel position of the electric vehicle before failure, and σIx: section passage current amount before failure.

  When the steady load current and the fault current approach each other, it is difficult to detect the fault in the conventional method. However, the change in the difference voltage detected by the present embodiment is expressed as follows. FIG. 18 shows the calculation result when the sum of σIX = 3PU and the section electric vehicle current I = 1PU, that is, the current before failure and the section fault current If = 4PU are equivalent. However, in the calculation, kα = 0.4, α = 1, and ZL = 1PU.

  In FIG. 18, dVmax in the differential voltage change amount graph according to the present embodiment is the maximum value of the differential voltage amount dV at both ends assumed in the steady state. In this embodiment, assuming that a change amount of ± 10% of the maximum value dVmax is detected, the difference voltage amount dVf at the time of failure is the difference voltage amount dV corresponding to the arbitrary position d of the electric vehicle traveling in the section at the steady state. The region exceeding ± dVmax is a failure detection region. That is, in the region where the position d of the electric vehicle running in the steady section is 0.7 PU or more, a failure that occurs in the whole area (df = 0 to 1), the position d of the electric vehicle running in the steady section is In the region of 0.7 PU or less, it is possible to detect a failure occurring at the failure position df = 0 to 0.8.

[Third Embodiment]
A feeder protection device and method for an AC AT feeder circuit according to a third embodiment of the present invention will be described. FIG. 7 shows the configuration of the section differential voltage system according to the present embodiment. The electrical terminals A and B at both ends of the section are equipped with protective devices 1A and 1B, and are used as instrument transformers VTA and VTB and current transformers. Feed voltages VA, VB, trolley wire currents ItA, ItB, feeder currents IfA, IfB at both ends of the section are introduced via CTtA, CTtB, CTfA, CTfB. The protection devices 1A and 1B at both ends of the section communicate the feeding voltages VA and VB and the trolley line currents ItA and ItB, the feeder currents IfA and IfB measured in synchronization with each other at an arbitrary period, and perform arbitrary sampling times. The same time series information is stored and updated. The protection devices 1A and 1B at both ends of the section flow the sampling time series information at both ends of the section to be stored and updated and the amplitude value, and flow into the difference dV between the voltages VA and VB at both ends of the section and the protection section of FIG. The fundamental wave component amount of the difference dI between the currents ItA, ItB, IfA, IfB is obtained. The section difference voltage dV to be obtained is obtained in the same manner as in the first embodiment, and the section inflow current dI is obtained as shown in Equation 21.

  With reference to FIG. 8, an interval difference voltage calculation method by the feeder protection device 1 of the present embodiment will be described. 3, that is, the difference voltage time series information by the difference voltage time series information calculation unit 11, the difference voltage fundamental wave component calculation unit 12, the difference voltage amount calculation unit 13, and the voltage base section failure detection unit 14. Since the calculation step, the difference voltage fundamental wave component calculation step, the difference voltage amount calculation step, and the voltage base section failure detection step are the same as those in the first embodiment, description thereof is omitted.

  In the difference current warning information calculation step, the difference current time series information calculation unit 15 stores the difference (equation 21) of the same-time sampling values of the both-end current information as the both-end difference current time-series information for any number of sampling times, Update each time.

  In the fundamental wave component amount calculating step, the fundamental wave component amount calculating unit 16 performs a filtering operation on the time series information of the differential current at both ends, and stores the fundamental wave component amount of the differential current at both ends as time series information for an arbitrary number of samplings. , Update each time.

  In the difference current amount calculation step, the difference current amount calculation unit 17 calculates the amplitude value of the fundamental wave component time series information of the difference current at both ends to obtain the difference current amount | dI |

  In the current base section failure detection step, the current base section failure detection unit 18 compares the difference current amount | dI | at both ends of the section obtained by calculating the amplitude value with a predetermined failure determination value kI to determine a section failure ( | DI | ≧ kI).

  In the final section failure determination step, the final section failure determination unit 19 determines the difference between the determination result of the voltage base section failure detection unit 14 of the difference voltage value | dV | in the voltage base section failure detection step and the difference in the current base section failure detection step. The determination result of the current base section failure detection unit 18 of the current value | dI | is logically processed, and when both are determined as failure, the operation of the protection device is output.

  As described above, in the feeder protection device and method according to the third embodiment, the current transformers CTtA, CTtB, CTfA, and CTfB for measuring instruments connected to the train lines are further added to the first embodiment. The current information passing through each end is measured every arbitrary sampling period, and is stored and updated as time series information for the number of arbitrary sampling times, and the difference current amount at both ends of the section is calculated from the same time series current information at both ends to be stored and updated. The section failure determination based on the difference voltage amount calculated in the same manner as in the first embodiment and the section failure determination based on the difference current amount are performed in parallel, and the final determination is made based on both determination results. Perform section failure judgment.

  Thereby, according to this Embodiment, there exist the following effects.

  1) Suppress unnecessary operation due to the voltage difference caused by the passing current outside the protection section.

The difference current | dI | obtained by the aforementioned equation 21 is a vector composite amount of the current at both ends of the section. According to the present invention, both the difference voltage amount | dV | at both ends of the section and the vector combined amount | dI | In other words, even if a difference voltage occurs at both ends due to the superposition of fault current passing through the healthy section, the fault current is not detected as the vector composite amount (inflow) of the current at both ends through the healthy section, so unnecessary operations are suppressed. it can.

  2) Suppress unnecessary operations due to differential voltage caused by poor introduction of secondary voltage for instrument transformers.

The voltage across the protection zone is introduced via an instrument transformer. If the introduction of the voltage at one end becomes defective (disconnection), a significant difference voltage is generated at both ends of the section, but the detected amount of the vector composite amount (inflow amount) of the current at both ends flows into the section at steady state. If it is larger than the electric vehicle current amount, failure detection can be suppressed.

[Fourth Embodiment]
A feeder protection device and method for an AC AT feeder circuit according to a fourth embodiment of the present invention will be described. The configuration of the feeder protection device 1 of the present embodiment is common to the third embodiment. According to the present embodiment, the protection devices 1A and 1B at both ends of the section have the feeding voltages VA and VB and the trolley line currents ItA and ItB, the feeder currents IfA and IfB measured in synchronization with each other at an arbitrary period. Are mutually stored at high speed, stored as the same time-series information for an arbitrary number of samplings, and updated. The protection devices 1A and 1B at both ends of the section perform the filtering calculation and the amplitude value calculation on the sampling time series information at both ends of the section to be stored and updated, and the voltages VA and VB at both ends and the current Ith passing outside the protection section are expressed by Equation 22 And the section difference voltage suppression amount dVX according to Equation 23 is determined to detect a section failure. In each equation, the turn ratio N of the autotransformer AT is 2 and the leakage impedance is ignored (ZAT = 0).

  Where I: current flowing into the protection section (failure current), d: section length distance ratio of the protection section inflow current position (line length ratio of the failure point to the protection section line length), ZL: train line impedance of the protection section , Kα: a difference voltage amount coefficient of a basic principle equation according to the vertical line coupling state, which is open (kα = 0.4) and coupling (kα = 0.2).

  With reference to FIG. 9, the configuration of the calculation function of the section difference voltage method and the feeding protection method by the feeding protection device 1 of the present embodiment will be described. The same reference numerals are used for the arithmetic elements in the first embodiment shown in FIG. 3 and the arithmetic elements in the third embodiment shown in FIG. 8, and the description thereof is omitted. That is, the difference voltage time series information calculation unit 11, the difference voltage fundamental wave component calculation unit 12, and the difference voltage amount calculation unit 13 are the same as those in the first embodiment, and the difference voltage time series information calculation step, the difference voltage by them The processing of the fundamental wave component calculation step and the difference voltage amount calculation step is also the same as in the first embodiment. Further, the difference current time series information calculation unit 15, the fundamental wave component amount calculation unit 16, and the difference current amount calculation unit 17 are the same as those of the third embodiment, and the difference current time series information calculation step, the fundamental wave component by them. The processing of the amount calculation step and the difference current amount calculation step is the same as that of the third embodiment.

  In the present embodiment, in each end current calculation step, each end current calculation unit 15a stores the current sampling information ItA, IfA, ItB, IfB at both ends of the section as each end current time series information, and updates each time.

  In each end current fundamental wave component amount calculation step, each end current fundamental wave component amount calculation unit 16a performs a filtering operation on each end current time-series information to obtain the fundamental wave component amount of each end difference current for an arbitrary number of samplings. It is stored as time series information and updated as needed.

  In each end current amplitude value calculation step, each end current amplitude value calculation unit 17a calculates the amplitude value of the fundamental wave component time-series information of each end current and calculates the current amount | ItA |, | IfA |, | ItB | and | IfB |

  In the section passing current calculation step, the section passing current calculation unit 20 calculates the difference current amount | dI | at both ends of the section obtained by Equation 21 by the difference current amount calculation step by the difference current amount calculation unit 17 and each end. Using the respective end current amounts | ItA |, | IfA |, | ItB |, | IfB | obtained in the respective end current amplitude value calculation steps by the current amplitude value calculation unit 17a, the current passing through the protection section is obtained as shown in Equation 22. Ith is calculated.

  In the passage current correction calculation step, the passage current correction calculation unit 21 calculates the difference voltage amount | dV | at both ends of the section obtained by the difference voltage amount calculation unit 13 by the section passage current calculation unit 20 as shown in Equation 23. The product of the obtained protection section passage current Ith and a predetermined constant ZL is subtracted to calculate a section difference voltage suppression amount dVX due to the protection section passage current.

  In the section failure determination step, the section failure determination unit 22 compares the difference voltage dVX suppressed by the protection section passage current with a predetermined failure determination value kV, and determines whether or not the section failure depends on whether or not | dVX | ≧ kV. Determine.

  As described above, the feeder protection device and method of the present embodiment is similar to the protection device and method of both ends of the third embodiment in that the current at both ends of the section obtained from the same time series information of the current at both ends of the protection section is obtained. Calculate the section passing current that flows through both ends of the section and flows outside the section from the scalar sum and the difference current amount at both ends of the section, multiply the section passing current amount by a predetermined line constant, and subtract from the difference voltage amount at both ends of the section The determined value is compared with a predetermined failure determination value kV to determine a section failure.

  Thereby, according to this Embodiment, there exist the following effects.

  1) The difference voltage detection sensitivity in the protection section can be remarkably improved.

  As described above, in the present embodiment, the section passing current Ith is calculated from the train line current at both ends of the section, and the difference voltage superposition amount | Ith | · of the protection section passing current component Ith from the difference voltage | dV | ZL is subtracted and removed, and the difference voltage amount | dVX | of the inflow current component in the section is detected. The number of electric cars traveling in an arbitrary protected section is less than the total number of electric cars traveling throughout the train line. However, by doing the above, it is possible to detect the difference voltage amount caused by the section inflow component having a value lower than the difference voltage amount generated by the total load current of the electric vehicle traveling throughout the protection section, and as a result. The differential voltage detection sensitivity can be remarkably improved.

[Fifth Embodiment]
A feeding protection apparatus and method for an AC AT feeding circuit according to a fifth embodiment of the present invention will be described. The configuration of the feeder protection device 1 of this embodiment is the same as that of the first embodiment shown in FIGS. 2A and 2B.

  In the first embodiment, the protection devices 1A and 1B at both ends of the protection section introduce a feeding voltage at each end, obtain a difference voltage | dV | at both ends of the protection section, and compare and determine the difference with the comparison constant kV. Detect failure.

  On the other hand, as shown in FIG. 10, when an electric vehicle enters a switching section that divides power, an inrush current due to re-pressurization of a transformer mounted on the electric vehicle flows by switching the power of the section. The value of the magnetizing inrush current is indefinite depending on the voltage phase at the time of re-pressurization of the power source, but the maximum is comparable to the fault current and changes sharply. However, the voltage difference between the protection sections calculated by Equation (7) and Equation (12) according to the first embodiment described above is the excitation inrush current at the time of re-pressurization with a value comparable to the failure current to be detected. Since it passes through the entire protection section d = 1PU, it is difficult to discriminate it from the difference voltage amount caused by the failure.

The magnetizing inrush current at the time of re-pressurization of the electric vehicle-mounted transformer flowing in the protection section when the electric vehicle enters the switching section will be described with reference to FIG. FIG. 10 is an up line in the section from the substation SS to the feeding section SP shown in the basic configuration of the AC AT feeding circuit in FIG. 1, and shows the protection section 2 (the auxiliary feeding section SSP to the feeding section SP). The electric vehicle that has entered the section switching section is re-pressurized with the power supply of the protection section-side substation SS, and the no-load inrush current ILin at the time of the re-pressurization is the SS power supply ~ protection section 1 ~ protection section 2-section Since the electric current flows to the repressurized electric vehicle and passes through the line impedance ZL of the entire protection section, the differential voltages dV1 and dV2 generated at both ends of the protection sections 1 and 2 are values of Expression 24 and Expression 24a. In each equation, the turn ratio N of the autotransformer AT is 2, and the leakage impedance is ignored (ZAT = 0).

  However, dV1: Section 1 differential voltage at both ends, kα: difference voltage amount coefficient of the basic principle equation according to the vertical line coupling state, open (kα = 0.4), coupling (kα = 0.22), dV2: section 2 Both-end differential voltage, α: function of upper and lower line coupling state, open (α = 1), coupling (α = 2).

  However, if the re-pressurized inrush current ILin in the fault current region passes through the entire section d = 1, it is difficult to determine the fault.

  FIG. 11 is an example of a measurement waveform of the differential voltage at both ends generated when the electric vehicle is repressurized in the power switching of the switching section. As is apparent from the waveform, the repressurization inrush current ILin contains a large amount of the second harmonic component, so if the content rate of the second harmonic component of the voltage difference dV across the section generated by the current is determined. It is possible to discriminate between electric vehicle repressurization and failure.

  FIG. 12 shows the configuration of the calculation function of the section difference voltage method by the feeder protection device 1 of the present embodiment. In FIG. 12, the same reference numerals are used for the same elements as those in the first embodiment shown in FIG. 3, and the description thereof is omitted. That is, the difference voltage time series information calculation unit 11, the difference voltage fundamental wave component calculation unit 12, the difference voltage amount calculation unit 13, and the voltage base section failure detection unit 14 are the same as those in the first embodiment, and the difference voltage generated by them. The processes of the time series information calculation step, the difference voltage fundamental wave component calculation step, the difference voltage amount calculation step, and the voltage base section failure detection step are also the same.

  In the present embodiment, in the second harmonic component calculation step, the second harmonic component calculation unit 23 performs a filtering operation on the time-series information of the voltage difference between both ends to perform the second harmonic of the voltage difference VA and VB at both ends. Wave components are stored as time-series information for an arbitrary number of samplings, and updated each time.

  In the second harmonic difference voltage calculation step, the second harmonic difference voltage calculation unit 24 calculates the amplitude value of the time series information of the second harmonic component of the differential voltage at both ends, and calculates the second harmonic differential voltage at both ends of the section. The quantity | dV2f |

  In the second harmonic content determination step, the second harmonic content determination unit 25 calculates the fundamental wave difference voltage amount | dV1f | at both ends of the section obtained by the difference voltage amount calculation unit 13 and the second harmonic difference voltage calculation. The second harmonic component content | dV2f | / | dV1f | is calculated using the second harmonic difference voltage amount | dV2f | obtained by the unit 24, and the calculated content rate and a predetermined content rate determination amount k2f are calculated. Are compared to determine whether or not the voltage difference is due to the electric vehicle repressurizing inrush current.

  In the final section failure determination step, the final section failure determination unit 26 performs failure determination based on the fundamental wave difference voltage amount | dV | in the voltage base section failure detection step performed by the voltage base section failure detection unit 14, and includes the second harmonic. Using the second harmonic content determination in the second harmonic content determination step by the rate determination unit 25, the fundamental wave difference voltage determination is not due to the electric vehicle repressurization inrush current by the logical product of both determinations, It is determined that the failure is due to a section failure. Otherwise, it is determined that there is no section failure.

  As described above, the feeder protection device and method according to the present embodiment provides a difference voltage time series of feeder voltages at both ends for the determination of the section failure based on the difference voltage amount at both ends of the protection section according to the first embodiment. The amount of second harmonic component contained in the difference voltage is calculated from the information, and if the content rate of the second harmonic exceeds a predetermined determination constant, the output of the section failure determination based on the difference voltage amount is suppressed.

  Thereby, according to this Embodiment, there exist the following effects.

  1) The difference voltage detection sensitivity in the protection section can be remarkably improved.

  When the electric vehicle is re-pressurized by switching the section power supply, an inrush current comparable to the fault current flows into the section section and passes through the train line in the other section. Therefore, a difference voltage (formula 7, formula 16, formula 23) that is equal to or exceeds the amount of fault detection occurs at both ends of the section, but the second harmonic component contained in the differential voltage By determining the content rate of the battery and suppressing the determination of the section failure based on the amount of differential voltage, unnecessary operation due to the electric vehicle repressurizing current can be suppressed. That is, it is possible to detect a value that is lower than the difference voltage amount generated by the electric vehicle repressurization current, or ignore it and ignore the difference voltage amount, and as a result, the difference voltage detection sensitivity in the protection section can be remarkably improved.

[Sixth Embodiment]
A feeding protection apparatus and method for an AC AT feeding circuit according to a sixth embodiment of the present invention will be described. The configuration of the feeder protection device 1 of this embodiment is the same as that of the third embodiment shown in FIG.

  In the third embodiment, the protective devices 1A, 1B at both ends of the section mutually measure the feeding voltages VA, VB, the trolley line currents ItA, ItB, the feeder currents IfA, IfB that are measured in synchronization with each other at an arbitrary period. High-speed communication is performed and stored as the same time-series information for any number of samplings and updated. The protection devices 1A and 1B at both ends of the section can detect a failure from the difference voltage | dV | and the difference current | dI | at both ends of the section obtained by filtering the sampling time series information at both ends of the section to be stored and updated and calculating the amplitude value. I try to detect it. However, the amount of difference voltage | dV | generated at both ends of the section in a steady state is affected by the current passing outside the section. As an example, as shown in the current distribution before failure in FIG. 13A, the electric vehicle load current σIX (= IX1 + IX2 + IX3) on the far end side from the power source V flows outside the section through the protection section ZL = 1PU, The differential voltage dV generated at both ends is a value of Expression 25 (similar to Expression 16 used in the second embodiment).

  On the other hand, when a fault occurs in the section, as shown in FIG. 13B, the fault current If flows at the fault position df in the protection section, and the electric vehicle load current is zeroed by stopping the control at a high speed due to a voltage drop due to the fault. Then, the difference voltage amount | dVf | between the both-ends voltages VA and VB at the time of the failure is a value of Equation 26.

In the comparison between the difference voltages dV and dVf at both ends before and after the failure, the relational expression for the difference voltage amount | dVf | at the time of failure exceeds the difference voltage amount | dV | In each formula, the turn ratio of the autotransformer AT is N and the leakage impedance is ignored (ZAT = 0).

  However, α is a coupling function of upper and lower lines, and is open (α = 1), coupling (α = 2), kα: a difference voltage amount coefficient of a basic principle equation corresponding to an upper and lower line coupling state, and is opened (kα = 0. 4) A bond (kα = 0.22).

  In Equation 27, which is a relational expression indicating the detection amount limit point where the difference voltage amount dVf at the time of failure exceeds the steady-state difference voltage amount dVL, failure detection is greatly influenced by the failure point position df and the section passing current σIX. The positions d and df of the currents I and If in the section before and after the failure are limited to a range of 0 to 1PU. Therefore, no matter how large the fault current If is, the right side increases and approaches infinity as the fault point position df decreases, and there is a region where fault detection is difficult. In addition, the failure determination becomes difficult as the out-of-interval passing current and the failure current approach in a steady state, or as the failure point approaches the power source side end rather than the intermediate position. That is, the conceptual condition of the failure detection drawn from the equation (27) is that a failure current more than twice the current σIX passing outside the section flows from the middle of the protection section to the end side position.

  The section differential voltage method by the feeder protection device 1 of the present embodiment eliminates the influence of the out-of-section passing current σIX in the steady state. FIG. 14 shows the configuration of the calculation function of the interval difference voltage method and the feeding protection method according to the present embodiment. In FIG. 14, the same reference numerals are used for elements common to the third embodiment shown in FIG. That is, the difference current time-series information calculation unit 15, the fundamental wave component amount calculation unit 16, the difference current amount calculation unit 17, and the current base section failure detection unit 18 are the same as those in the third embodiment, and the difference current time is determined by them. Since the processing of the sequence information calculation step, fundamental wave component amount calculation step, difference current amount calculation step, and current base section failure detection step is the same, description thereof will be omitted.

  In the feeder protection device 1 of the present embodiment, in each end voltage calculation step, each end voltage calculation unit 27 stores the end voltages VA and VB at both ends of the section as the same sampling time series information, and updates each time. .

  In each end fundamental wave component amount calculation step, each end fundamental wave component amount calculation unit 28 performs filtering operation on the time series information of the end voltage, and stores the fundamental wave component amount as time series information for an arbitrary number of samplings. , Update each time.

In each end voltage change amount calculation step, each end voltage change amount calculation unit 29 calculates the amplitude value of the fundamental wave component time-series information of each end voltage and stores the past for an arbitrary cycle of the voltage amounts VA and VB at each end. Changes ΔVA and ΔVB between t−n and the current t0 are obtained. The change amounts ΔVA and ΔVB at each end are obtained as shown in Equations 28 and 29 from the conceptual diagrams of FIGS. 13A and 13B showing before and after the failure and the equivalent circuit shown in FIG. 13C.

  Where V: power supply voltage, Zp: line impedance from the power supply to the protection section, N: turn ratio of the single-turn transformer AT, If: failure current, I: section electric vehicle current before failure, σIx: before failure DVto: differential voltage across the section at the time of failure, dVt-n: differential voltage across the section before the failure, kα: difference voltage amount coefficient of the basic principle formula according to the vertical line coupling state, and open (kα = 0.4), coupling (kα = 0.22), α: coupling function of upper and lower lines, open (α = 1), coupling (α = 2).

In the change amount base section failure detection step, the change amount base section failure detection unit 30 obtains a scalar sum ΣΔV (= | ΔVA | + | ΔVB |) of each end change amount ΔVA, ΔVB by Equation 30 and determines a predetermined failure. A section fault is determined by comparing with the determination value kσV.

  In the final section failure detection step, the final section failure detection unit 31 determines the failure based on the difference current amount | dI | in the current base section failure detection step by the current base section failure detection unit 18, and the variation amount base section failure detection unit. The final section failure determination result is output by the logical product of both determinations with the scalar sum | ΣΔV | at the change amount-based section failure detection step 30.

Taking the change amount ΣΔV generated in the scalar sum of the voltage changes at both ends of the section obtained by Equation 30 as a conceptual example, the vertical line coupling function α is 1 and the differential voltage amount coefficient kα according to the vertical line coupling state is 0. 4. If the line impedance of the section length is ZL, the fault current is If, the inflow current in the section before the fault is I, the section passing current before the fault is σIX, and the current before and after the fault is the same, the section before the fault The amount of voltage change corresponding to the position d of the internal current I and the failure point df of the failure current If is a value of Equation 31. The calculation result is shown in FIG.

  In FIG. 15, the difference voltage dV across the straight line is a value corresponding to the position d of the current before failure. The differential voltage dVf across the straight line is a value corresponding to the post-fault current position df. As is apparent from the comparison between these two dV and dVf, the maximum differential voltage dVf = 1.6PU (value of df = 1) at the time of failure is the maximum differential voltage dV = 1.9PU (value of d = 1) before the failure. ). That is, no failure can be detected at the failure points in the entire protection section. On the other hand, the scalar sum ΣΔV (= | ΔVA | + | ΔVB |) of the end change amounts ΔVA, ΔVB | according to the present embodiment is the V of Δ0.1d, Δ0.5d, Δ1.0d, ΔdV in FIG. Indicated by line and horizontal lines. The horizontal line ΔdV is the sum of each end voltage change scalar before the failure | ΔVAt0−ΔVAt−n | + | ΔVBt0−ΔVBt−n |. As described above, the value is the current increase time constant of the electric vehicle and the detection of the amount of change. It is compressed at the blind time ratio and reduced to about 10% of the maximum differential voltage dV = 1.9 · PU before failure. The V broken lines Δ0.1d, Δ0.5d, and Δ1.0d indicate that the position d of the current I before the failure depends on the failure position df with respect to each end voltage change amount of 0.1PU, 0.5PU, 1.0PU. The resulting end voltage change scalar sum | ΔVAft0−ΔVAt−n | + | ΔVBft0−ΔVBt−n |.

  As apparent from FIG. 15, an unprotectable region that is less than the sum of each end voltage change scalar of about 0.2 PU width occurs in the entire protection interval, but the protection interval region is greatly expanded. Further, if the fault current amount 4PU in the calculation example condition of FIG. 15 increases by about 0.8 PU, fault detection becomes possible in the entire area.

  As described above, the feeding protection device and method according to the sixth embodiment of the present invention both perform the difference current amount determination at both ends of the protection section and the voltage change amount scalar sum determination at both ends according to the third embodiment. Detects a fault in the section.

  Thereby, according to this Embodiment, there exist the following effects.

  1) The difference voltage detection sensitivity in the protection section can be remarkably improved.

  According to the present embodiment, at both ends of the protection section, the voltage difference between the present and the past by an arbitrary blind time width is detected as the voltage change amount at each end (Equation 28, Equation 29), A failure is detected from the scalar sum (Equation 30). In other words, the amount of change in the voltage at both ends that occurs during steady electric vehicle travel is largely suppressed by the current increase time constant of the electric vehicle and the optional blind time for detection of the change amount. It is possible to detect the increase / decrease change scalar sum of the voltage at both ends without any suppression. Thereby, the difference voltage due to the failure can be detected with a value significantly lower than the amount of difference voltage generated by the electric vehicle current passing outside the protection section. As a result, the difference voltage detection sensitivity in the protection section can be significantly improved.

  2) Unnecessary operation due to differential voltage caused by poor introduction of instrument transformer secondary voltage can be suppressed.

  The voltage across the protection zone is introduced through an instrument transformer. If the introduction of the voltage at one end becomes defective (disconnection), a noticeable voltage difference will occur at both ends of the section, but the amount of vector synthesis (inflow) of the current at both ends of the protection section in the steady state does not reach the detected fault amount Operation can be suppressed.

  In addition, this invention is not limited to the said embodiment, The feed protection apparatus which combined the structure of the 1st-6th embodiment arbitrarily, and the feed protection method by it can be comprised.

DESCRIPTION OF SYMBOLS 1 Feeder protective device 11 Difference voltage time series information calculation part 12 Difference voltage fundamental wave component calculation part 13 Difference voltage amount calculation part 13a Difference voltage amount calculation part 14 Voltage base section failure detection part 15 Difference current time series information calculation part 15a End current calculation unit 16 Fundamental wave component amount calculation unit 16a Each end current fundamental wave component amount calculation unit 17 Difference current amount calculation unit 18 Current base section failure detection unit 19 Final section failure determination unit 20 Section passage current calculation unit 21 Pass current correction Calculation section 22 Section failure determination section 23 Second harmonic component calculation section 24 Second harmonic difference voltage calculation section 25 Second harmonic content determination section 26 Final section failure determination section 27 Each end voltage calculation section 28 Each end fundamental wave Component amount calculation unit 29 Voltage change calculation unit at each end 30 Change amount base section fault detection unit 31 Final section fault detection unit AT Autotransformer CT Current transformer for SS SS Substation SP Feeding section SSP Supplement Feeding circuit section post

Claims (12)

In the AC self-winding transformer feeding circuit, a feeder protection device that detects a failure of a train line that is bounded by the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information terminal means for measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and sharing the feeding voltage information at each end as the same time-series voltage information at both ends by high-speed communication with each other;
Difference voltage time series information calculating means for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating means for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating means for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount;
A feeding protection device for an AC AT feeding circuit, comprising: a voltage base section fault detecting means for detecting a section fault by comparing and determining the difference voltage fundamental wave component amount and a predetermined constant.   2. The alternating current AT feeder circuit according to claim 1, wherein the difference voltage fundamental wave component calculation means calculates the difference voltage fundamental wave component amount based on an increase amount of a current value with respect to a past value at an arbitrary time point. Snorkeling protection device. In the AC self-winding transformer feeding circuit, a feeder protection device that detects a failure of a train line that is bounded by the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information terminal means for measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and sharing the feeding voltage information at each end as the same time-series voltage information at both ends by high-speed communication with each other;
Difference voltage time series information calculating means for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating means for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating means for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount;
Train line current acquisition means for taking in both ends of the protected section from the secondary side of the current transformer at the end of each electric station,
Current information terminal means for measuring the train line current captured at each end of the electric station for each arbitrary period, and sharing the train line current at each end as the same time-series current information at both ends by high-speed communication with each other,
Difference current calculation means for calculating the same time series current information at both ends to obtain difference current time series information;
A difference current fundamental wave component calculating means for filtering the difference current time series information to obtain time series information of the difference current fundamental wave component;
A difference current fundamental wave component amount calculating means for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component;
Section fault detection means for comparing and determining the difference voltage fundamental wave component amount and a predetermined constant, comparing and determining the difference current fundamental wave component amount and a predetermined constant, and detecting a section fault from both determination results And a feeding protection device for an AC AT feeding circuit. In the AC self-winding transformer feeding circuit, a feeder protection device that detects a failure of a train line that is bounded by the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information terminal means for measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and sharing the feeding voltage information at each end as the same time-series voltage information at both ends by high-speed communication with each other;
Difference voltage time series information calculating means for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating means for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating means for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount;
Train line current acquisition means for taking in both ends of the protected section from the secondary side of the current transformer at the end of each electric station,
Current information terminal means for measuring the train line current captured at each end of the electric station for each arbitrary period, and sharing the train line current at each end as the same time-series current information at both ends by high-speed communication with each other,
Difference current calculation means for calculating the same time series current information at both ends to obtain difference current time series information;
A difference current fundamental wave component calculating means for filtering the difference current time series information to obtain time series information of the difference current fundamental wave component;
A difference current fundamental wave component amount calculating means for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component;
Current time series information calculating means for calculating current time series information at each end by calculating the same time series current information at both ends;
Fundamental wave current time series information calculating means for obtaining fundamental wave current time series information at each end by filtering the current time series information at each end;
A fundamental wave current component amount calculating means for calculating a fundamental wave current component amount at each end by calculating an amplitude value of the fundamental wave current time series information at each end;
Section passage current amount calculation means for obtaining a section passage current amount from the difference current fundamental wave component amount and the fundamental wave current component amount at each end;
Equivalent difference voltage calculation means for multiplying the section passing current amount by a predetermined line constant and subtracting from the difference voltage fundamental wave component amount to obtain a section inflow current amount equivalent difference voltage;
A feeding protection device for an AC AT feeding circuit, comprising section fault detecting means for comparing and determining the section inflow current amount equivalent differential voltage and a predetermined constant to detect a section fault. In the AC self-winding transformer feeding circuit, a feeder protection device that detects a failure of a train line that is bounded by the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information terminal means for measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and sharing the feeding voltage information at each end as the same time-series voltage information at both ends by high-speed communication with each other;
Difference voltage time series information calculating means for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating means for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating means for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount;
Voltage base section fault detection means for comparing and determining the difference voltage fundamental wave component amount and a predetermined constant to detect a section fault;
Second harmonic time series information calculating means for filtering the difference voltage time series information to obtain second harmonic time series information of the difference voltage;
A difference voltage second harmonic component amount calculating means for calculating a difference voltage second harmonic component amount by calculating an amplitude value of the second harmonic time series information of the difference voltage;
Second harmonic content calculating means for calculating the second harmonic content of the differential voltage from the ratio calculation of the differential voltage second harmonic component amount and the differential voltage fundamental wave component amount;
A section that compares and determines the second harmonic content with a predetermined determination constant, and suppresses a section failure determination by the voltage-based section failure detection means when the second harmonic content exceeds a predetermined determination constant. A feeding protection device for an AC AT feeding circuit, characterized by comprising failure determination inhibiting means. In the AC self-winding transformer feeding circuit, a feeder protection device that detects a failure of a train line that is bounded by the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition means for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information terminal means for measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and sharing the feeding voltage information at each end as the same time-series voltage information at both ends by high-speed communication with each other;
Train line current acquisition means for taking in both ends of the protected section from the secondary side of the current transformer at the end of each electric station,
Current information terminal means for measuring the train line current captured at each end of the electric station for each arbitrary period, and sharing the train line current at each end as the same time-series current information at both ends by high-speed communication with each other,
Difference current calculation means for calculating the same time series current information at both ends to obtain difference current time series information;
A difference current fundamental wave component calculating means for filtering the difference current time series information to obtain time series information of the difference current fundamental wave component;
A difference current fundamental wave component amount calculating means for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component;
A current base section failure detection means for comparing and determining the difference current fundamental wave component amount and a predetermined constant to detect a section failure;
Voltage time series information calculating means for obtaining voltage time series information at each end from the same time series voltage information at both ends of the protection section;
Voltage fundamental wave time series information calculating means for filtering the voltage time series information at each end to obtain fundamental wave time series information of the voltage at each end; and
Voltage fundamental wave component amount calculating means for calculating an amplitude value of the fundamental wave time-series information of the voltage at each end to obtain a voltage fundamental wave component amount at each end;
A voltage change amount calculating means for obtaining a voltage change amount between a past value and a current value of the voltage fundamental wave component amount at each end, for each end;
A voltage change amount calculating means for adding a voltage change amount at each end to obtain a scalar sum;
Section fault detection means for comparing and determining the difference current fundamental wave component amount and a predetermined constant, comparing and determining a scalar sum of the voltage change amount and a predetermined constant, and detecting a section fault from both determination results; A feeder protection device for an AC AT feeder circuit, comprising: In the AC self-winding transformer feeding circuit, a feeding protection method for detecting a failure of a train line bordering on the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information sharing step of measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and performing high-speed communication with each other and sharing the feeding voltage information at each end as the same time-series voltage information at both ends,
A difference voltage calculation step for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating step for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating step for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount; and
A feeding protection method for an AC AT feeder circuit, comprising: a voltage base section fault detection step of detecting a section fault by comparing and determining the difference voltage fundamental wave component amount and a predetermined constant.   8. The alternating current AT feeder circuit according to claim 7, wherein the difference voltage fundamental wave component calculation step calculates the difference voltage fundamental wave component amount based on an increase amount of a current value with respect to a past value at an arbitrary time point. Snorkeling protection method. In the AC self-winding transformer feeding circuit, a feeding protection method for detecting a failure of a train line bordering on the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information sharing step of measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and performing high-speed communication with each other and sharing the feeding voltage information at each end as the same time-series voltage information at both ends,
A difference voltage calculation step for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating step for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating step for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount; and
Train line current acquisition step for capturing both-end train line currents of the protected section from the secondary side of the current transformer at each electrical station end;
A current information sharing step of measuring the train line current captured at each of the electrical station ends for each arbitrary cycle, and sharing the train line current at each end as the same time-series current information at both ends by performing high-speed communication with each other,
A difference current calculation step for calculating difference current time series information by calculating the same time series current information at both ends; and
A difference current fundamental wave component calculating step for filtering the difference current time series information to obtain time series information of the difference current fundamental wave component;
A difference current fundamental wave component amount calculating step for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component;
Section failure detection step of comparing and determining the difference voltage fundamental wave component amount and a predetermined constant, comparing and determining the difference current fundamental wave component amount and a predetermined constant, and detecting a section failure from the determination results of both And a feeding protection method for an AC AT feeding circuit. In the AC self-winding transformer feeding circuit, a feeding protection method for detecting a failure of a train line bordering on the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information sharing step of measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and performing high-speed communication with each other and sharing the feeding voltage information at each end as the same time-series voltage information at both ends,
A difference voltage calculation step for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating step for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating step for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount; and
Train line current acquisition step for capturing both-end train line currents of the protected section from the secondary side of the current transformer at each electrical station end;
A current information sharing step of measuring the train line current captured at each of the electrical station ends for each arbitrary cycle, and sharing the train line current at each end as the same time-series current information at both ends by performing high-speed communication with each other,
A difference current calculation step for calculating difference current time series information by calculating the same time series current information at both ends; and
A difference current fundamental wave component calculating step for filtering the difference current time series information to obtain time series information of the difference current fundamental wave component;
A difference current fundamental wave component amount calculating step for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component;
A current time series information calculating step for calculating current time series information at each end by calculating the same time series current information at both ends;
A fundamental wave current time series information calculation step for obtaining a fundamental wave current time series information at each end by filtering the current time series information at each end; and
A fundamental wave current component amount calculating step for calculating a fundamental wave current component amount at each end by calculating an amplitude value of the fundamental wave current time series information at each end;
A section passing current amount calculation step for obtaining a section passing current amount from the difference current fundamental wave component amount and the fundamental wave current component amount at each end;
Equivalent difference voltage calculation step of multiplying the section passage current amount by a predetermined line constant and subtracting from the difference voltage fundamental wave component amount to obtain a section inflow current amount equivalent difference voltage;
An AC AT feeder circuit feeding protection method comprising: a section failure detection step of comparing and determining the section inflow current amount equivalent differential voltage and a predetermined constant to detect a section failure. In the AC self-winding transformer feeding circuit, a feeding protection method for detecting a failure of a train line bordering on the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information sharing step of measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and performing high-speed communication with each other and sharing the feeding voltage information at each end as the same time-series voltage information at both ends,
A difference voltage calculation step for calculating the same time series voltage information at both ends to obtain difference voltage time series information;
A difference voltage fundamental wave component calculating step for filtering the difference voltage time series information to obtain time series information of the difference voltage fundamental wave component;
A difference voltage fundamental wave component amount calculating step for calculating an amplitude value of the time series information of the difference voltage fundamental wave component to obtain a difference voltage fundamental wave component amount; and
A voltage-based section failure detection step of comparing and determining the difference voltage fundamental wave component amount and a predetermined constant to detect a section failure;
Second harmonic time series information calculating step for filtering the difference voltage time series information to obtain second harmonic time series information of the difference voltage;
A difference voltage second harmonic component amount calculating step for calculating a difference voltage second harmonic component amount by calculating an amplitude value of the second harmonic time series information of the difference voltage;
A second harmonic content calculating step of calculating a second harmonic content of the differential voltage from a ratio calculation of the differential voltage second harmonic component amount and the differential voltage fundamental wave component amount;
A section that compares and determines the second harmonic content with a predetermined determination constant, and suppresses the section failure determination by the voltage-based section failure detection step when the second harmonic content exceeds a predetermined determination constant. A method for protecting the feeding of an AC AT feeding circuit, comprising: a step of inhibiting failure determination. In the AC self-winding transformer feeding circuit, a feeding protection method for detecting a failure of a train line bordering on the self-winding transformer of an electric station arranged for each arbitrary distance section,
Feeding voltage acquisition step for capturing the feeding voltage at both ends of the protection section from the secondary side of the instrument transformer at each electrical station end,
Voltage information sharing step of measuring the feeding voltage captured at each of the electrical station ends for each arbitrary period, and performing high-speed communication with each other and sharing the feeding voltage information at each end as the same time-series voltage information at both ends,
Train line current acquisition step for capturing both-end train line currents of the protected section from the secondary side of the current transformer at each electrical station end;
A current information sharing step of measuring the train line current captured at each of the electrical station ends for each arbitrary cycle, and sharing the train line current at each end as the same time-series current information at both ends by performing high-speed communication with each other,
A difference current calculation step for calculating difference current time series information by calculating the same time series current information at both ends; and
A difference current fundamental wave component calculating step for filtering the difference current time series information to obtain time series information of the difference current fundamental wave component;
A difference current fundamental wave component amount calculating step for calculating a difference current fundamental wave component amount by calculating an amplitude value of the time series information of the difference current fundamental wave component;
A current base section fault detection step of comparing and determining the difference current fundamental wave component amount and a predetermined constant to detect a section fault;
A voltage time series information calculating step for obtaining voltage time series information at each end from the same time series voltage information at both ends of the protection section;
A voltage fundamental wave time series information calculating step for obtaining a fundamental wave time series information of a voltage at each end by filtering the voltage time series information at each end, and
A voltage fundamental wave component amount calculating step for calculating an amplitude value of the fundamental wave time-series information of the voltage at each end to obtain a voltage fundamental wave component amount at each end;
A voltage change amount calculating step for obtaining a voltage change amount between a past value and a current value of the voltage fundamental wave component amount at each end;
A voltage change amount calculating step for obtaining a scalar sum by adding the voltage change amount at each end; and
A section failure detection step of comparing and determining the difference current fundamental wave component amount and a predetermined constant, comparing and determining a scalar sum amount of the voltage change amount and a predetermined constant, and detecting a section failure from both determination results; A feeding protection method for an AC AT feeding circuit, comprising:

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