JP3915050B2 - Accident current detection device and accident section discrimination method in feeding equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an accident current detection device that detects an accident current that flows when an accident such as a ground fault occurs in an AC feeder section of an electric railway, and to determine an accident section by installing a plurality of such accident current detection devices. It is related with the accident section discrimination method to do.
[0002]
[Prior art and problems to be solved by the invention]
Conventionally, in the AC railway section of an electric railway, when an accident such as a ground fault occurs, the fault point (failure point) is specified by the distance determined by the locator installed at the substation. It is done to the standard. This method measures the circuit impedance of the feeder circuit from the substation to the failure point, so if a capacitor is installed in the feeder circuit, does the capacitor protection bypass circuit operate? Since the circuit impedance varies greatly depending on whether or not, a large error occurs in the orientation distance to the failure point. For this reason, a great deal of time and labor is spent identifying the failure point and the failure section, and it is difficult to quickly check the feeder and recover from the accident.
[0003]
The present invention has been made to solve the above-described conventional problems, and its purpose is to easily and reliably detect an accident current flowing through a feeder when an accident such as a ground fault occurs. An object of the present invention is to provide an accident current detection device that can be easily installed in an existing feeder. Another object of the present invention is to provide an accident section determination method capable of quickly and accurately specifying an accident section by installing a plurality of accident current detection devices in an AC feeder section.
[0004]
[Means for Solving the Problems]
Therefore, an accident current detection device according to claim 1 is supplied with a current deriving unit for diverting a current flowing through an AC feeder, a current detecting unit for detecting a current derived by the current deriving unit, and an output current of the current detecting unit. A current determination unit that determines whether or not the current flowing through the AC feeder is an accident current, and a display unit that is connected to the current determination unit and displays externally when the current flowing through the AC feeder is an accident current. And the current determination unit determines that the current is an accident current when the load current is not detected within a predetermined time after the instantaneous current is detected .
[0006]
According to the accident current detection device of the first aspect, when an accident such as a ground fault occurs, the accident current flowing through the feeder can be detected easily and reliably. Further, the current lead-out portion is fixed to the negative electric wire by a clamp or the like, and the case in which the apparatus main body is accommodated is fixed to the feeder's electric pole or the like, so that it can be easily attached to the existing feeder.
[0007]
Further, according to a second aspect of the present invention, there is provided a method for determining an accident section, wherein the fault current detection device according to the first aspect is installed in an AC feeder every time the booster transformer is arranged, and the accident section is determined using the booster transformer arrangement interval as a unit section. It is characterized by.
[0008]
According to the accident section discriminating method of the second aspect , it is possible to quickly and accurately locate the accident location.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, specific embodiments of the fault current detection apparatus and fault section determination method in the power feeding facility of the present invention will be described in detail with reference to the drawings.
[0010]
As shown in FIG. 1, in a booster transformer (BT) type AC feeder circuit, booster transformers BT1, BT2, BT3,... Are installed at predetermined intervals, and the power from the substation S is boosted to generate stable power. Supplying load (train). The current flowing from the trolley T to the rail R through a load (not shown) is sucked up by the negative wire NF through the sucking wires E1 and E2, and returns to the substation S. One siphoning line E1, E2 is installed for each section where the booster transformers BT1, BT2, BT3,. At least one fault current detection device D1, D2, D3 is installed between each booster transformer BT1, BT2, BT3.
[0011]
If a ground fault occurs at the current position P, the current due to the ground fault (accident current) is sucked up from the rail R through the suction line E2 to the negative wire NF, and passes through the booster transformers BT2 and BT1 to the substation S. Flow into. The accident current is a short-circuit current that flows instantaneously, and each of the accident current detection devices D1, D2, and D3 detects such a short-circuit current.
[0012]
FIG. 2 shows a configuration of an embodiment of the fault current detection apparatus. The fault current detection device includes a pair of connection lines 1 and 1 as a current deriving unit connected to the negative wire NF as a current shunt. Each end of the connecting wires 1 and 1 is fixed and held on the negative wire NF. The negative wire NF is not cut, and the connecting wires 1 and 1 are simply clamped together with the existing negative wire NF by the holding portions 2 and 2 to form a branch path for the negative wire NF.
[0013]
The current flowing through the connection lines 1 and 1 is guided into the case 4 through the bushings 3 and 3. This case 4 houses a current detection circuit (current detection unit) 5, a current determination unit 6, a control unit 7, a display unit 8, an output relay 9, etc. that constitute the main part of the accident current detection device. . The current introduced into the case 4 is detected by the current detection circuit 5, and the output current is supplied to the current determination unit 6. The current determination unit 6 determines whether the current from the current detection circuit 5 is an instantaneous current that has flowed due to an accident such as a ground fault or a load current due to running of a train. In the case of an instantaneous current due to a ground fault or the like, it is determined that an accident has occurred, and the display unit 8 such as an LED indicating that the accident has occurred is turned on (for example, red). In the case of current due to a train load, the display unit 8 such as an LED is turned on (for example, green). The controller 7 controls the lighting of the LEDs and the like. However, the lighting of the LED may be displayed only when an accident occurs, and the lighting may not be displayed in the case of a train load current. Further, in the case of an accident current, the control unit 7 may operate the output relay 9 with the detection signal and transmit the contact signal to the substation or feeding circuit monitoring place.
[0014]
3, 4, and 5 are diagrams illustrating an example of a method for determining whether the detected current is a current due to an accident or a current due to a load (train). First, in the flowchart shown in FIG. 3, in step S1, the current Is output from the current detection circuit 5 is equal to or higher than the first level (H level) set relatively high, and the current duration Ts is instantaneous. It is determined whether or not (millisecond order). If so (YES), the process proceeds to step S2, the output current of the current detection circuit 5 after the instantaneous current detection is equal to or higher than the second level (L level) set lower than the above, and It is determined whether or not the current duration is a relatively long time (second order). When YES is determined in this step, the process proceeds to step S3, where it is determined that this current is a load (train) current, and no accident is displayed (step S4). In addition, no accident is displayed in the case of NO in step S1 (step S4). On the other hand, in the case of NO in step S2, it is determined that the current Is is an accident current (step S5), and an accident display is made with an LED or the like (step S6).
[0015]
The determination method as described above is employed for the following reason. That is, in the case of a load current due to a train, the load current IL continues to flow in the AC feeder circuit for a relatively long time TL as shown in FIG. 5, but before this load current IL, as shown in FIG. Since the instantaneous current Is may flow as the inrush current, the accident current or the load current can be accurately identified by using the determination method of FIG.
[0016]
According to the above fault current detection device, the current deriving portion (connection line 1) is fixed to the negative wire NF by a clamp, and the case 4 in which the device main body is housed is fixed to the feeder wire post or the like. In addition, it can be attached to existing feeders at low cost, and the accident current can be easily and reliably determined.
[0017]
Next, an embodiment of the accident section determination method will be described. As shown in FIG. 1, it is possible to quickly and surely specify the accident section by installing at least one of the above fault current detection devices for each installation section of the booster transformers BT1, BT2, BT3. It becomes possible. In the example of FIG. 1, if there is a ground fault at the current position P, the current (accident current) due to the ground fault is sucked up from the rail R through the suction line E2 to the negative wire NF, and booster transformers BT2, BT1. Through and into the substation S. For this reason, the instantaneous (accident) current Is is detected in some fault current detection devices D2 and D1, and is not detected in other fault current detection devices D3. Therefore, at the time of maintenance / inspection, the presence or absence of an accident display of the accident current detection devices D1, D2, D3... Is checked, and the two accident current detection devices D2 and D3 adjacent to each other have a detection device with an accident display and an accident. The accident section can be specified by confirming the positions of the detection devices without display. In the above example, it can be determined that an accident has occurred in the section between the booster transformers BT2 and BT3 from the position of the fault current detection devices D2 and D3.
[0018]
Therefore, it is possible to locate the accident location more accurately by using the accident section determination method as a supplement to the distance location method to the accident point by the existing position locator (locator). In other words, in the position locator, when it is difficult to specify whether the accident point is between the booster transformers BT1 and BT2 or between the booster transformers BT2 and BT3, It is possible to quickly and accurately identify the location. Further, by transmitting the accident detection signal (output of the relay 9) of each device to the substation or the monitoring station, it is possible to determine the accident section even from a remote place.
[0019]
【The invention's effect】
According to the accident current detection device of the first aspect, when an accident such as a ground fault occurs, the accident current flowing through the feeder can be detected easily and reliably. Further, the current lead-out portion is fixed to the negative electric wire by a clamp or the like, and the case in which the apparatus main body is accommodated is fixed to the feeder's electric pole or the like, so that it can be easily attached to the existing feeder.
[0020]
Further, according to the accident section discrimination method of the second aspect , it is possible to quickly and accurately locate the accident position.
[Brief description of the drawings]
FIG. 1 is a circuit explanatory diagram showing an embodiment of an accident current detection device and an accident section discrimination method according to the present invention.
FIG. 2 is a block diagram for explaining an embodiment of the fault current detection apparatus.
FIG. 3 is a flowchart for explaining an accident current determination method of the embodiment of the accident current detection apparatus.
FIG. 4 is a current waveform explanatory diagram for explaining a method of distinguishing an accident current from a load current in the accident current determination method.
FIG. 5 is a current waveform explanatory diagram for explaining a method of distinguishing an accident current from a load current in the accident current determination method.
[Explanation of symbols]
1 Connection line (current derivation section)
5 Current detection circuit (current detection unit)
6 Current determination unit 7 Control unit 8 Display unit BT Booster transformer D1 Accident current detection device D2 Accident current detection device D3 Accident current detection device

Claims (2)

A current deriving unit for diverting the current flowing through the AC feeder, a current detecting unit for detecting the current derived by the current deriving unit, and the current flowing through the AC feeder when the output current of the current detecting unit is supplied or of whether or not to determine the current determination unit, comprising a display unit current flowing through the connected wire-out the AC in the current determination unit to an external display when a fault current, the current determination section, instantaneous An accident current detection device in a feeder system, characterized by determining an accident current when a load current is not detected within a predetermined time after detecting a current.   Accident section determination in feeders, characterized in that the fault current detection device according to claim 1 is installed in an AC feeder every time the booster transformer is arranged, and the accident section is discriminated with the arrangement interval of the booster transformer as a unit section. Method.

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