KR102432403B1 - Distribution line failure detection system using ground manual switch - Google Patents

Abstract

The present invention relates to an underground distribution line failure detection system and an operating method thereof, a failure detection device for determining whether a failure has occurred by measuring the current of an underground distribution line, and an operator who receives the failure occurrence information and displays the status information on a single line diagram It includes a PC, and the fault detection device is a power transformer that is attached to a power cable of a distribution line and acquires power by electromagnetic induction method, a current measuring current that is attached to a power cable of a distribution line to measure current, for current measurement A terminal device that determines whether a fault has occurred based on the current measured by the current transformer and encodes the line operation information including the fault occurrence information and the battery voltage value of the fault detection device periodically measured, and the encrypted line operation information and the battery voltage value It may include a communication device for transmitting the to the operator PC.
According to the present invention, as a failure section is detected in units of switchgear, the failure recovery time of the underground distribution line can be significantly shortened, and the power of the manual switch can be efficiently supplied by utilizing energy harvesting and sleep mode, and between devices. The protection of system operation information can be strengthened by adding a security function that encrypts and decrypts system operation information during communication.

Description

Distribution line failure detection system using ground manual switch

The present invention relates to a system and operating method for determining whether a failure occurs in real time through current measurement using a distribution line failure detection device installed in an underground manual switchgear and providing failure information to an operator.

In domestic 22.9kV extra-high voltage distribution lines, manual switchgear or automatic switchgear to find the fault point by opening and closing the line load in the event of a fault is being operated.

In particular, in the case of an underground distribution line than in the case of an overhead distribution line, it is difficult to determine the location of a fault and to recover it.

In case of automatic switchgear, automatic terminal device is installed, so it is possible to monitor and measure the status of the distribution line from a remote location, and to remotely control the closing/opening in case of a line failure, so it is easy to separate the faulty section and restore the healthy section.

However, in the case of an underground line, the installation of an automatic switchgear is expensive, and the fault current of the underground line is mostly over 4,000A and there is a problem that it is damaged due to equipment deterioration. There is a risk that this will happen.

On the other hand, in the case of a manual switchgear, when a line failure occurs, the operator directly manipulates the closing/opening of the switchgear.

However, it is possible to detect line failure by attaching an automatic device to the existing manual switchgear. However, unlike the automatic switchgear, manual switchgear does not have a separate power supply device, so it is difficult to secure power, and the power supply is excessive in the communication process for remote control. There are problems that need to be done.

In the underground distribution line, a fault detection device is installed in the manual switchgear installed in advance to measure the current flowing in the distribution line to determine whether a fault has occurred in real time, and fault information (fault indicator) is sent to the distribution center and branch offices. We propose a system that provides fault information to the operator by transmitting it to the operator PC in which the distribution automation program is installed in real time.

In the existing current transformers for power, efficient energy harvesting was difficult because the required power could be secured when at least 15A of current per phase flows.

In addition, since there is a problem in that excessive power is required to drive the device for fault detection of a manual switchgear, a device in which power consumption is minimized by switching to a sleep mode, etc. is proposed.

Here, we also propose a method to strengthen the protection of system operation information by adding a security function that encrypts and decrypts system operation information during communication between the main server and the automatic device of the manual switchgear.

The technical problems to be achieved in this document are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the description below. There will be.

An underground distribution line failure detection system according to various embodiments of the present invention includes: a failure detection device for determining whether a failure has occurred by measuring a current of the underground distribution line; and an operator PC that receives the fault occurrence information determined by the fault detection device and displays the status information on the single line diagram,

The failure detection device may include: a current transformer for a power supply attached to a power cable of the distribution line to acquire power by an electromagnetic induction method; a current measuring current transformer attached to the power cable of the distribution line to measure the current; a terminal device for determining whether a fault has occurred based on the current measured by the current measuring current transformer, and for encrypting the line operation information including the fault occurrence information and the periodically measured storage battery voltage value of the fault detecting device; and a communication device for transmitting the encrypted line operation information and the battery voltage value to the operator PC.

According to various embodiments of the present disclosure, the current transformer for power may include: a core iron piece of an integral circular shape, not a separate type, so as to minimize the loss of the acquired power; and a circular detachable enclosure that facilitates installation and removal of the core iron piece in a state of being attached to the power cable of the distribution line.

According to various embodiments of the present disclosure, the current measuring current transformer includes: a CT unit for measuring a current flowing in a power cable of the distribution line; and a fixing unit for attaching and detaching the CT unit to the power cable.

According to various embodiments of the present disclosure, the current measuring current transformer may measure a current value of 100A or more and 1000A or less.

According to various embodiments of the present disclosure, the terminal device may include a fault determination unit configured to determine whether a fault has occurred in the distribution line based on a current value measured by the current measuring current transformer; a power supply unit supplying the electrical energy obtained by using the power current transformer to the failure detection device; and a communication unit that controls the communication device and encrypts the line operation information including the fault occurrence information determined by the fault determination unit and the battery voltage value of the fault detection device periodically measured.

According to various embodiments of the present disclosure, the encrypted line operation information and the battery voltage value may be transmitted to the operator PC through the gateway of the distribution center.

According to various embodiments of the present invention, failure information is displayed on the single-line diagram based on the line operation information and the storage battery voltage value received from the failure detection device, and the communication state and the battery power? can be displayed

According to various embodiments of the present disclosure, the communication period between the failure detection device and the operator PC may be changed in units of 1 hour in the range of 1 hour to 24 hours, and the default setting value may be set to 1 hour.

According to various embodiments of the present disclosure, the terminal device switches to a sleep mode when the voltage of the storage battery decreases below a set value in order to minimize the use of power to detect the occurrence of a failure of the distribution line in real time. It is possible to perform only a function of monitoring as a function and perform an encryption process before transmitting the failure occurrence information to the operator PC by switching to a wake-up mode when the occurrence of the failure is detected.

According to various embodiments of the present disclosure, the communication device maintains a sleep mode that consumes only low power, and transmits the line operation information and the fault detection device status information from the terminal device to the operator PC. Upon receiving or receiving a control command signal from the operator PC, it may switch to a wake-up mode and transmit the line operation information and the fault detection device status information to the operator PC.

According to various embodiments of the present disclosure, a security module capable of encryption and decryption is further included in each of the failure detection device and the operator PC, and communication between the operator PC and the gateway is serial to enhance security. This can be done through communication.

A method of operating an underground distribution line failure detection system according to various embodiments of the present disclosure includes: obtaining line operation information including current flowing in the distribution line and failure occurrence information; obtaining state information of the fault detection device by measuring a battery voltage of the fault detection device; transmitting the line operation information and status information of the failure detection device to an operator PC; transmitting a reception response to the fault detection device when the operator PC normally receives the line operation information and the status information of the fault detection device; and if the reception response does not come within a set time, retransmitting the line operation information and status information of the failure detection device to an operator PC.

According to various embodiments of the present disclosure, when the operator PC requests the line operation information and the status information of the failure detection device from the operator PC to the failure detection device, the failure detection device transmits a reception response to the request to the operator PC. transmitting; and transmitting, by the fault detection device, the requested line operation information and status information of the fault detection device to an operator PC.

According to various embodiments of the present disclosure, when resetting the failure occurrence information, transmitting a failure occurrence information reset command from the operator PC to the failure detection device; transmitting, by the failure detection device, which has received the reset command, a reception response to the reset command to an operator PC; retransmitting, by the operator PC, the reset command to a failure detection device when the received response does not come within a set time; resetting, by the fault detection device, fault occurrence information; transmitting, by the failure detection device, reset information to an operator PC; deleting, by the operator PC, the fault occurrence information displayed in the single-line diagram when the reset information is received; and transmitting, by the operator PC, a reception response to the failure detection device.

According to various embodiments of the present disclosure, the set time may be set to 30 seconds, and the maximum number of retransmissions may be set to 3 times.

According to various embodiments, since the fault section is detected in units of the switchgear, it is not necessary to cut the substation circuit for separating the fault section or to put in the automatic switchgear, thereby remarkably shortening the fault recovery time.

According to various embodiments, it is possible to prevent secondary equipment from being damaged because it is not necessary to cut the circuit of the substation for determining the fault section or to send the automatic switchgear.

According to various embodiments, it is possible to quickly and accurately detect a faulty section of a line by using a manual switch at a much lower cost (about 1/20) compared to the cost of replacing the underground line manual switch with an automatic switch.

According to various embodiments, by controlling the power consumption of the terminal device and the communication device by using the sleep mode and the wake-up mode, the energy harvesting technology can be efficiently utilized in the manual switch.

According to various embodiments, the system operation information protection can be strengthened by adding a security function for encrypting and decrypting the system operation information during communication between the main server server and the automatic device of the manual switch.

Effects obtainable in the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those of ordinary skill in the art to which the present disclosure belongs from the description below. will be.

1 is a diagram illustrating an internal configuration of a failure detection device and a communication concept with an operator PC, according to various embodiments of the present disclosure.
2 is a diagram illustrating an embodiment of a failure detection device according to various embodiments of the present disclosure;
3 is a view showing each configuration constituting a current transformer for power, according to various embodiments of the present disclosure.
4 is a diagram illustrating an embodiment in which a current transformer for power and a current transformer for power are attached to a distribution line according to various embodiments of the present disclosure.
5 is a view showing each configuration constituting a current measuring current transformer according to various embodiments of the present disclosure.
6 is a diagram illustrating an embodiment in which a current measuring current transformer and a current measuring current transformer are attached to a distribution line according to various embodiments of the present disclosure.
7 is a diagram illustrating an information exchange method between a failure detection device installed in a manual switch and an operator PC installed in a distribution center according to various embodiments of the present disclosure.
8 is a flowchart illustrating a two-way communication process regarding line operation and device status information between a fault detection device and an operator PC, according to various embodiments of the present disclosure.
9 is a flowchart illustrating a bidirectional communication process related to a reset command of a fault occurrence signal between a fault detection device and an operator PC according to various embodiments of the present disclosure.
10 is a diagram illustrating a bidirectional communication process of encryption and decryption by an encryption module according to various embodiments of the present disclosure.
11 is a diagram illustrating a process of detecting a failure section in a switchgear unit according to various embodiments of the present disclosure;
In connection with the description of the drawings, the same or similar reference numerals may be used for the same or similar components.

Hereinafter, various embodiments will be described in detail with reference to the accompanying drawings.

Regardless of the reference numerals, the same or similar components are assigned the same reference numerals, and overlapping descriptions thereof may be omitted.

The suffix 'module' or 'part' for the components used in the following description is given or mixed in consideration of only the ease of writing the specification, and does not have a meaning or role distinct from each other by itself. In addition, 'module' or 'unit' refers to software or hardware components such as field programmable gate array (FPGA) or application specific integrated circuit (ASIC), but is not limited to software or hardware. A 'unit' or 'module' may be configured to reside on an addressable storage medium or may be configured to reproduce one or more processors. Thus, as an example, 'part' or 'module' refers to components such as software components, object-oriented software components, class components and task components, and processes, functions, properties, and programs. may include procedures, subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functionality provided in one component, 'unit' or 'module' may be combined into a smaller number of components and 'unit' or 'module' or additional components and 'unit' or 'module' can be further separated.

The steps of a method or algorithm described in connection with some embodiments of the present invention may be directly implemented in hardware executed by a processor, a software module, or a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of recording medium known in the art. An exemplary recording medium is coupled to the processor, the processor capable of reading information from, and writing information to, the storage medium. Alternatively, the recording medium may be integral with the processor. The processor and recording medium may reside within an application specific integrated circuit (ASIC). The ASIC may reside within the user terminal.

Terms including ordinal numbers such as first, second, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

When it is said that an element is 'connected' or 'connected' to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is mentioned that a certain element is 'directly connected' or 'directly connected' to another element, it should be understood that there is no other element in the middle.

First, the terms used in this specification will be briefly described.

The switchgear is installed on the distribution line and used to open and close the distribution line when necessary, such as fault recovery of the distribution line, truce work, and load conversion.

Distribution Automation System (DAS) refers to distribution facility site information (status information, current/voltage, failure presence, etc.) acquired from a distribution line automation terminal device installed on a distribution line directly to the main device through a communication device. It means a comprehensive system that can provide and monitor on-site distribution lines in real time.

A current transformer (CT) is a device in which primary and secondary coils are wound around an iron core like a transformer, and it converts a large current flowing in a circuit into a small current less than the rated current according to a predetermined ratio. It is used to expand the measurable range.

Energy harvesting refers to a technology that collects wasted energy and uses it as power. It is a self-generation device using a current transformer (CT), and it can supply driving power for various communication devices in a high-voltage power line environment where it is difficult to supply power. .

Single Line Diagram (SLD) is the basis of various electrical connection diagrams. It refers to a diagram that shows the electrical connection relationship between devices and the system with a single line, and shows the connection and types of instruments and relays for other monitoring. do.

Serial communication refers to a process of continuously transmitting data one bit at a time through a communication channel or a computer bus.

Hereinafter, various embodiments will be described in detail according to the accompanying drawings.

1 is a diagram illustrating an internal configuration of a failure detection device 100 and a communication concept with an operator PC 200 according to various embodiments of the present disclosure.

Referring to FIG. 1 , the underground distribution line failure detection system may include a failure detection device 100 on the manual switch 10 side and an operator PC 200 on the distribution center 20 side. Here, the fault detection device 100 can determine whether a fault has occurred by measuring the current of the underground distribution line, and the operator PC 200 receives the fault occurrence information determined by the fault detection device 100 and displays the status information in the single line diagram. can be displayed.

The failure detection device 100 may include a terminal device 110 , a current transformer 120 for power, a current measurement current transformer 130 , and a communication device 140 .

Here, the terminal device 110 determines whether a fault has occurred based on the current measured by the current measuring current transformer 130 , and the line operation information including fault occurrence information (Fault Indicator, F.I) and the periodically measured fault It is possible to perform a function of encrypting the voltage value of the storage battery of the detection device 100 .

The terminal device 110 may include a failure determination unit 111 , a power supply unit 112 , and a communication unit 113 .

The fault determination unit 111 monitors whether a fault has occurred in the distribution line in real time based on the current value measured by the current measuring current transformer 130, and periodically measures the voltage stored in the capacitor of the fault detection device 100. It is possible to determine the state information of the failure detection device 100 .

The power supply unit 112 may supply the electrical energy obtained by using the current transformer 120 for power to the failure detection device 100 to operate it. At this time, in the existing current transformer for power supply, it is possible to secure the required power only when a current of at least 15A per phase flows. it is possible to obtain This will be described again below.

The communication unit 113 can control the communication device 140, and the line operation information including the fault occurrence information determined by the fault determination unit 111 and the battery voltage value of the fault detection device 100 measured periodically. An encryption operation can be performed. This encryption operation may be separately performed by the encryption module 141, which will be described below.

The current transformer 120 for power may be attached to a power cable of a distribution line to obtain power for driving the failure detection device 100 by energy harvesting, more specifically, electromagnetic induction.

The current transformer 120 for power may be composed of a core iron piece 121 and a detachable enclosure 122 . Since the core iron piece 121 of the present invention is made of an integrated circular shape, there is no breakage compared to the conventional U-shaped (semi-circular), and the resistance of the iron piece is small, so the loss of acquired power can be minimized, and the efficiency of power acquisition is high. have. The detachable enclosure 122 has a circular shape and can be separated by semi-circular parts, so it is easy to attach and detach from the power cable. .

The current measuring current transformer 130 may measure the current by attaching it to the power cable of the distribution line. Current measuring current transformer 130 may be composed of a CT unit 131 for measuring the current flowing in the power cable of the distribution line, and the fixed unit 132 responsible for attaching and detaching between the CT unit 131 and the power cable. As described above, the CT unit 131 and the fixing unit 132 are separately configured to facilitate attachment and detachment to the power cable.

Current measuring current transformer 130 can measure a current value of 100A or more and 1000A or less, and if it is out of this range, it is saturated and accurate measurement is impossible.

The communication device 140 may transmit the encrypted line operation information and the storage battery voltage value to the operator PC 200 through the gateway 250 of the distribution center 20 . In order to prevent hacking, the PC in the internal network 40 may be configured as an independent network that is not linked to other systems, and a serial method may be applied to communication between the gateway 250 and the operator PC 200 .

The operator PC 200 may be installed in the distribution center 20 or the distribution operation room, and may be equipped with a failure detection program 210 . Here, the distribution automation system (DAS) program (control, single-line diagram, alarm, etc.) and system DB can be utilized, so there is an advantage that separate program production and DB construction are not required.

The operator PC 200 displays the failure information on the single-line diagram based on the line operation information and the storage battery voltage value received from the failure detection device 100 using the mounted failure detection program 210, and communicates in the status window. Condition and battery before?陋だ? can be displayed

In addition, the communication period between the failure detection device 100 and the operator PC 200 may be changed in the range of 1 hour to 24 hours, and the default setting value may be set to 1 hour.

In relation to the energy harvesting technology, the driving power of the failure detection device 100 attached to the manual switch 10 utilizes the power acquired from the power current transformer 120 to use the electrical energy stored in the storage battery as the power source. . Therefore, it is necessary to minimize the power consumption of the fault detection device 100, and in particular, the terminal device 110 and the communication device 140 use most of the power in the configuration of the fault detection device 100, so the power consumption of these two devices. is necessary to control

In the case of the terminal device 110, fault occurrence information, which is important information among the line operation information (current, fault current, fault occurrence information (Fault Indicator, F.I)) and device status information (storage battery voltage), transmitted to the operator PC 200 (Fault Indicator) and a function of transmitting only battery voltage information may be included. By transmitting only necessary information when necessary, power consumption can be reduced. In addition, it is possible to reduce the power consumption by minimizing the number of communication by setting the communication period in units of hours, days, and months.

In addition, when the battery voltage decreases below a set value (eg, 5.7V), the terminal device 110 may switch to a sleep mode in which only a real-time monitoring function of the occurrence of a failure in the distribution line is performed. In this case, when a failure occurs, it may switch to a wake-up mode and transmit the fault occurrence information (Fault Indicator, F.I) to the operator PC 200 . Here, in the case of the sleep mode, automatic scheduling according to the communication period with the operator PC 200 is stopped, thereby preventing the failure detection device 100 from being shut down due to insufficient power of the storage battery.

In the case of the communication device 140, it can operate in a normal sleep mode (Sleep mode), and receives the line operation information and the fault detection device 100 status information transmission signal from the terminal device 110 to the operator PC 200. Alternatively, upon receiving a control signal from the operator PC 200 , it may be switched to a wake-up mode.

As described above, the power consumption of the failure detection device 100 can be minimized through the sleep mode function of the terminal device 110 and the communication device 140 .

2 is a diagram illustrating an embodiment of the failure detection apparatus 100 according to various embodiments of the present disclosure.

Referring to FIG. 2 , the failure detection device 100 includes one terminal device 110 , an LTE modem 142 antenna connected to the communication unit 113 of the terminal device 110 , three power transformers 120 , and nine Current measuring current transformer 130 may be operated as one set.

Here, in the case of the manual switchgear 10 of the underground distribution line, the power-side circuit enters and branches out into three, and each consists of three phases, so the current transformer 120 for power is attached to each phase of the power-side circuit, so three are required, Current measuring current transformer 130 is attached to each phase of the three branched out circuits to measure the current of each line, so a total of nine are required.

3 is a view showing each configuration constituting the current transformer 120 for power according to various embodiments of the present disclosure.

Referring to FIG. 3 , the current transformer 120 for power may be composed of an integral circular core iron piece 121 and a detachable enclosure 122 .

In Figure 3 (a), the core iron piece 121 may be formed in an integral circular shape. Conventionally, it is common to form a U-shape (semi-circle) in the form of hooking the power cable, but in the present invention, it is configured in a circular shape to prevent an increase in resistance due to a break in the middle, resulting in higher power acquisition efficiency during energy harvesting. can bring Conventionally, a current of 15A or more per phase is required to be used as a driving power source, but due to efficiency improvement due to the integrated circular power current transformer 120, only a current of 5A or more per phase can be used as a driving power source.

In FIG. 3(b), the enclosure 122 is in a form that is separated so as to be attached to the power cable, and may include an inner space and a cover in which the integral circular core iron piece 121 can be installed.

4 is a diagram illustrating an embodiment in which a current transformer 120 for power and a current transformer 120 for power are attached to a distribution line according to various embodiments of the present disclosure.

Referring to FIG. 4 , in FIG. 4A , the core iron piece 121 may be installed in the enclosure 122 to configure the current transformer 120 for power. It may include a cable that can be connected to the power supply unit 112 of the terminal device 110 in the failure detection device 100 .

In Fig. 4(b), when a current transformer 120 for power is attached to the power cable of the distribution line, and the current flowing in the power cable is changed, an electromagnetic induction phenomenon occurs in the core iron piece 121 to generate an induced electromotive force, energy harvest This can be used as a power source for driving the failure detection device 100 through the setting.

5 is a view showing each configuration constituting the current measuring current transformer 130 according to various embodiments.

Referring to FIG. 5 , the current measuring current transformer 130 may include a CT unit 131 and a fixing unit 132 .

In FIG. 5( a ), the CT unit 131 can measure the current flowing in the power cable of the distribution line in real time, and can measure it even when a large fault current occurs due to a ground fault 500 or the like. At currents less than 100A and more than 1000A, it shows saturation characteristics, so it is possible to measure current values of 100A or more and 1000A or less.

In FIG. 5(b) , the fixing part 132 may attach the CT unit 131 to the power cable, and may include an adjustable screw-type clamp to be attached to the power cable of various thicknesses.

Since the CT unit 131 and the fixing unit 132 exist independently, there is an advantage that it is easy to attach and detach the power cable.

6 is a diagram illustrating an embodiment in which a current measuring current transformer 130 and a current measuring current transformer 130 are attached to a distribution line according to various embodiments of the present disclosure.

Referring to FIG. 6 , in the case of the current measuring current transformer 130 for current measurement in FIG. 6( a ), three may be used together by being attached to each of the three-phase power cables, and in FIG. 6( b ) the screw type of the fixing part 132 . It is possible to stably fix the current measuring current transformer 130 according to the thickness of the power cable with the clamp.

7 is a diagram illustrating an information exchange method between the failure detection device 100 installed in the manual switch 10 and the operator PC 200 installed in the distribution center 20 according to various embodiments of the present disclosure.

Referring to FIG. 7 , the manual switch 10 side may include a failure detection device 100 and a communication device 140 , and the communication device 140 may include an encryption module 141 and an LTE modem 142 . have. Serial communication is performed between the encryption module 141 and the LTE modem 142 .

The information transmitted from the fault detection device 100 to the operator PC 200 includes line operation information (current, fault current, fault occurrence information (Fault Indicator, F.I)) and fault detection device 100 status information (storage battery voltage). may be included.

In the case of line operation information, the current is measured in units of 10A, and when the current exceeds 30A compared to the existing current, the current change information can be transmitted to the operator PC 200 . The current reference value for transmitting the current change information to the operator PC 200 may change the setting in units of 30A.

If the current value is measured over 400A, it can be judged as a fault current. The reference value for fault current judgment can be changed in units of 10A. When the fault detection device 100 determines that the fault current is a fault current, fault occurrence information may be generated and transmitted to the operator PC 200 together with the fault current value.

The state information of the failure detection device 100 may be determined by the battery voltage. The battery voltage is measured by the power supply unit 112 of the terminal device 110 and may be measured in units of 0.1V. If the battery voltage drops below 5V, it can be judged as defective. The measurement unit can be set between 0.1V and 1V.

Existing automatic switchgear has built-in current and voltage measuring devices and power supply, so it is possible to acquire necessary line operation information such as current, voltage, harmonics, and fault current in real time. On the other hand, the failure detection system using the manual switch 10 proposed in the present invention attaches the failure detection device 100 to the manual switch 10 separately to check whether a failure has occurred in the distribution line and the status information of the failure detection device 100 Since it is possible to obtain the minimum necessary information for the switch, there is an advantage that the cost can be greatly reduced compared to the conversion of the pre-installed manual switch 10 to the automatic switch 520 .

The line operation information and the state information of the failure detection device 100 transmitted from the manual switch 10 side failure detection device 100 are encrypted through the encryption module 141, and through the LTE modem 142 through serial communication. It may be transmitted to the distribution center 20 through a communication company network corresponding to the network 30 . Here, in the case of the distribution center 20, since the internal network 40 is used for security, it is connected to the internal network 40 through a dedicated line from the communication company network, passes through the gateway 250 including an encryption module, is decrypted, and serial communication In this way, the line operation information and the state information of the failure detection device 100 may be transmitted to the operator PC 200 . In this way, while reinforcing security, the line operation information and the state information of the failure detection device 100 are transmitted to the operator PC 200 in real time by using the communication network in the form of an alarm, or the failure detection device 100 from the operator PC 200 ) to request transmission of line operation information and device status information, the failure detection device 100 may transmit the request information.

8 is a flowchart illustrating a two-way communication process regarding line operation information and device status information between the failure detection device 100 and the operator PC 200 according to various embodiments of the present disclosure.

8, in operation S300, the line operation information (current, fault current, fault occurrence information) measured by the fault detection device 100 and the fault detection device 100 status information (storage battery voltage) are transmitted to the operator PC 200 ) can be transmitted.

In operation S310 , the operator PC 200 may transmit an information reception response to the failure detection device 100 when the information reception is completed.

In operation S320, the failure detection device 100 does not retransmit the information when receiving a reception response from the operator PC 200, but the same information when the reception response does not come within a predetermined time (eg, 30 seconds after transmission) can be retransmitted.

In operation S330, the failure detection apparatus 100 may set the number of retransmissions. For example, if three times are set, transmission of line operation information and device status information may be attempted up to three times.

As another embodiment, the operator PC 200 may first request the line operation information and the state information of the failure detection apparatus 100 to the failure detection device 100 . Here, the failure detection apparatus 100 may transmit the requested information after transmitting a reception response to the information request to the operator PC 200 . In this case, too, the operator PC 200 may retransmit the same information request to the failure detection device 100 when the reception response does not come within a predetermined time (eg, 30 seconds after the information request).

Through this method, it is possible to increase the reliability of transmission and reception of line operation information and device state information between the failure detection device 100 and the operator PC 200 .

9 is a flowchart illustrating a bidirectional communication process related to a reset command of a fault occurrence signal between the fault detection device 100 and the operator PC 200 according to various embodiments of the present disclosure.

Referring to FIG. 9 , in operation S400 , the operator PC 200 may transmit a fault occurrence information reset command to the fault detection device 100 .

In operation S410 , the failure detection device 100 may immediately transmit a command reception response to the operator PC 200 upon receiving the reset command and perform a reset operation of deleting the failure occurrence information.

In operation S420 , the failure detection device 100 may transmit reset information to the operator PC 200 after the reset operation is completed.

Here, when the operator PC 200 does not receive the command reception response of the failure detection device 100 in operation S410 within a predetermined time (for example, 30 seconds after command transmission), the operator PC 200 performs the failure detection device 100 ) to retransmit the same reset command. In this case, the operator PC 200 may set the maximum number of retransmissions. For example, if three times are set, the reset command transmission may be attempted up to three times (S430, 440).

In operation S450 , when the operator PC 200 normally receives the reset information of the failure detection device 100 , the failure occurrence information indicated in the single line diagram of the operator PC 200 may be deleted.

In operation S460 , the operator PC 200 may transmit a reception response to the failure detection device 100 after deletion of the failure occurrence information is completed.

Through this method, the fault occurrence information displayed in the distribution line disconnection diagram of the operator PC 200 and the fault occurrence information of the fault detection device 100 are deleted and reset together, so that between the operator PC 200 and the fault detection device 100 Matching of the failure occurrence information can be maintained.

Additionally, in the case of using a wireless communication network such as LTE, in order to secure communication reliability between the failure detection device 100 and the operator PC 200, the communication state is basically maintained for 30 seconds, and the communication state maintenance time is set in seconds. This is possible.

10 is a diagram illustrating a bidirectional communication process of encryption and decryption by the encryption module 141 according to various embodiments of the present disclosure.

Referring to FIG. 10 , an encryption module 141 capable of encrypting and decrypting line operation information, device state information, and control signals may be embedded in each of the failure detection device 100 side and the operator PC 200 side. Here, the encryption module 141 may be configured separately.

The encryption module 141 encrypts the line operation information and device state information to be transmitted from the terminal device 110 of the failure detection device 100 when transmitting information from the failure detection device 100 to the operator PC 200, and encrypts The received information may be transmitted to the operator PC 200 by utilizing the communication network. The operator PC 200 side may decrypt the encrypted information with the mutually agreed authentication key. Conversely, the same method may be applied to a case where a control signal or information is transmitted from the operator PC 200 to the failure detection device 100 .

Information security may be strengthened by applying a serial communication method between the operator PC 200 and the gateway 250 .

Specifically, by applying the serial communication method between the gateway 250 and the operator PC 200 directly connected to the external Internet network, it is possible to compensate for the disadvantages of the IP (Internet Protocol) communication method, which is weak in security.

11 is a diagram illustrating a process of detecting a failure section in a switchgear unit according to various embodiments of the present disclosure.

Referring to FIG. 11 , the square represents the manual switch 10 and the circle represents the automatic switch 520 .

In general, when a failure occurs in the distribution line, the failure section is separated in units of the automatic switchgear 520 in the distribution center 20, and the manual switch 10 can be separated from the distribution operation room to find the faulty section. . Thereafter, the power distribution center 20 may control the input of a circuit breaker (CB) or an automatic switch 520 , and the power distribution center 20 may perform power transmission in a healthy section.

Here, it is necessary to put in the circuit breaker or the automatic switch 520 of the substation about 2 to 3 times to isolate the faulty section. , secondary damage such as equipment damage can be prevented.

For example, when a ground fault 500 occurs between Guro #14 and Guro #13 of the distribution line, a large fault current of 4000 A or more flows in the fault section. Only 36, a large current could be sensed, and fault information (Fault Indicator, F.I) could be recognized. However, in the present invention, by attaching the fault detection device 100 to the manual switch 10, the manual switch 10, Guro# In Fig. 14, fault occurrence information can be recognized. This has the advantage of reducing the failure recovery time because the failure section can be known in more detail.

Based on the method described above, as the fault section is detected in units of the switchgear, there is no need to cut the substation circuit for separating the fault section or to put the automatic switch 520 in, thereby significantly shortening the fault recovery time of the underground distribution line. By using energy harvesting and sleep mode, the power of the manual switch 10 can be efficiently supplied, and the system operation information protection can be strengthened by adding a security function that encrypts and decrypts the system operation information during device-to-device communication. can

10: manual switch
20: distribution center
30: off-premises network
40: internal network
100: fault detection device
110: terminal device
111: fault determination unit
112: power supply
113: communication department
120: current transformer for power
121: core iron piece
122: enclosure
130: current measuring current transformer
131: CT unit
132: fixed part
140: communication device
141: encryption module
142: LTE modem
200: operator PC
210: fault detection program
250: gateway
500: ground fault
520: automatic switchgear

Claims (15)

In the underground distribution line failure detection system,
a fault detection device for determining whether a fault has occurred by measuring the current of the underground distribution line; and
and an operator PC installed in a distribution center or a distribution operation room, receiving the failure occurrence information determined by the failure detection device and displaying the status information on a single line diagram,
The failure detection device is installed with respect to a pre-installed manual switch,
a current transformer for power that is attached to the power cable of the distribution line and acquires power by electromagnetic induction;
a current measuring current transformer attached to the power cable of the distribution line to measure the current;
a terminal device for determining whether a fault has occurred based on the current measured by the current measuring current transformer, and for encrypting the line operation information including the fault occurrence information and the periodically measured storage battery voltage value of the fault detecting device; and
A communication device for transmitting the encrypted line operation information and the battery voltage value to the operator PC,
The terminal device is
Based on the current value measured by the current measuring current measuring current value, the power distribution line is monitored in real time whether a fault has occurred, and the voltage stored in the capacitor of the fault detection device is periodically measured to determine the status information of the fault detection device. fault determination unit;
a power supply unit supplying the electrical energy obtained by using the power current transformer to the failure detection device; and
A communication unit that controls the communication device and encrypts the line operation information including the fault occurrence information determined by the fault determination unit and the storage battery voltage value of the fault detection device periodically measured,
If a failure occurs in the sleep mode, which performs only real-time monitoring of distribution line failure, it switches to the wake-up mode and transmits the failure occurrence information to the operator PC. .
According to claim 1,
The current transformer for the power supply,
One-piece circular core iron piece that minimizes the loss of acquired power; and
An underground distribution line failure detection system comprising a circular detachable enclosure that is easy to install and remove the core iron piece in a state of being attached to the power cable of the distribution line.
According to claim 1,
The current measuring current transformer,
a CT unit for measuring the current flowing in the power cable of the distribution line; and
An underground distribution line failure detection system comprising a fixing unit for attaching and detaching the CT unit to the power cable.
4. The method of claim 3,
The current measuring current transformer,
An underground distribution line failure detection system that can measure current values of 100A or more.
delete According to claim 1,
The communication device is
Transmitting the encrypted line operation information and the storage battery voltage value to the operator PC through the gateway of the distribution center, an underground distribution line failure detection system.
According to claim 1,
The operator PC,
On the basis of the line operation information and the battery voltage value received from the failure detection device, the failure information is displayed on the single-line diagram, and the communication status and the battery voltage value are displayed on the status window. Displayed, underground distribution line fault detection system.
8. The method of claim 7,
The communication cycle between the failure detection device and the operator PC can be changed in units of 1 hour in the range of 1 hour to 24 hours, and the default setting value is 1 hour, the underground distribution line failure detection system.
According to claim 1,
The terminal device is
When the voltage of the storage battery decreases below a set value, it switches to a sleep mode and performs only a function of monitoring the occurrence of a failure of the distribution line in real time, and when the occurrence of the failure is detected, a wake-up mode (Wake- up mode) to perform an encryption process before transmitting the failure information to the operator PC, an underground distribution line failure detection system.
7. The method of claim 6,
The communication device is
While maintaining a sleep mode that consumes only low power, when receiving a command signal to transmit line operation information and fault detection device status information from the terminal device to the operator PC, or receiving a control command signal from the operator PC An underground distribution line failure detection system that converts to a wake-up mode and transmits the line operation information and the failure detection device status information to the operator PC.
7. The method of claim 6,
Further comprising a security module capable of encryption and decryption in each of the failure detection device and the operator PC,
Communication between the operator PC and the gateway is performed by a serial communication method, an underground distribution line failure detection system.
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