KR102848078B1 - Power cable fault detection device and Power cable fault detection method using the same - Google Patents

Abstract

A power cable fault detection device utilizing an optical cable includes an optical cable arranged adjacent to the power cable with a predetermined distance therebetween, an optical signal generator supplying an optical signal to the optical cable, an optical signal detection unit connected to the optical cable and detecting an optical signal supplied from the optical signal generator, and a control unit storing normal characteristics of the optical signal in a normal state of the power cable, and calculating a possibility of fault in the power cable based on the degree to which the detected optical signal deviates from the normal characteristics of the optical signal when it is determined that the optical signal detected by the optical signal detection unit deviates from the normal characteristics of the optical signal.

Description

Power cable fault detection device and power cable fault detection method using the same {Power cable fault detection device and power cable fault detection method using the same}

The present invention relates to a power cable fault detection device and a power cable fault detection method using the same, and more specifically, to a power cable fault detection device capable of continuously monitoring a power cable using a sensing optical cable and detecting a fault occurrence point from an acoustic signal generated by the generation of a fault, and a power cable fault detection method using the same.

When a power cable fault occurs, the thumping method is often used to detect the location of the fault. This method works by detecting the acoustic signals generated by magnetic changes or partial discharges at the fault location when a high voltage is applied to the power cable.

However, utilizing this principle presents the inconvenience of applying high voltage to power cables and using magnetic sensors to detect magnetic changes along the cable's installed path, or monitoring by moving microphones to detect acoustic signals. Furthermore, the accuracy of the distance to the fault detection point ranges widely, from tens to hundreds of meters, increasing the cost and time required to repair the power cable.

Accordingly, the purpose of the present invention is to provide a power cable fault detection device capable of accurately identifying a fault detection point using a sensing optical cable, and a power cable fault detection method using the same.

In order to achieve the above object, a power cable fault detection device utilizing an optical cable according to the present invention comprises: an optical cable disposed adjacent to the power cable with a predetermined distance; an optical signal generator supplying an optical signal to the optical cable; an optical signal detection unit connected to the optical cable and detecting an optical signal supplied from the optical signal generator; and a control unit storing normal characteristics of the optical signal in a normal state of the power cable, and calculating a fault probability of the power cable based on the degree to which the detected optical signal deviates from the normal characteristics of the optical signal when the optical signal detected by the optical signal detection unit is determined to deviate from the normal characteristics of the optical signal. Since the optical cable is disposed adjacent to the power cable and the optical intensity, scattering, and frequency of the detected optical signal deviate from the normal optical intensity range, normal scattering range, and normal frequency range, the fault probability can be calculated based on the degree to which the optical signal deviates, thereby accurately determining a fault in the power cable.

Here, the normal characteristics of the optical signal include at least one of a normal light intensity range, a normal scattering range, and a normal frequency range of the optical signal, and the control unit determines, if the light intensity of the detected optical signal exceeds the normal light intensity range, whether the frequency of the detected optical signal exceeds the normal frequency range, and if so, sequentially determines whether the scattering of the detected optical signal exceeds the normal scattering range, so that an accurate fault in the power cable can be determined, which is preferable.

And, the control unit stores the pattern of change in the optical intensity and frequency of the optical cable in response to a failure in the power cable, and it is preferable that the possibility of a failure in the power cable be calculated based on the similarity between the pattern of change in the optical intensity and frequency of the optical signal detected from the optical signal detection unit and the pattern of change in the failure, so that an accurate failure in the power cable can be determined.

Here, it is preferable to further include a communication unit capable of transmitting data to an external device, and the control unit controls the communication unit to transmit the calculated possibility of failure to a preset user terminal when the calculated possibility of failure exceeds a first predetermined value, thereby notifying the user that there is a possibility of failure in the power cable.

And it further includes a voltage boosting unit that can supply voltage by pressurizing the power cable, and the control unit supplies the voltage of the power supplied to the power cable at a second voltage that is at least lower than the first voltage currently supplied when the calculated possibility of failure exceeds a second predetermined value that is higher than the first predetermined value, and when the calculated possibility of failure becomes lower than the second predetermined value again, the voltage of the power supplied to the power cable is supplied again at the first voltage, so that when the possibility of failure becomes high, the power voltage is adjusted to a lower value and when the possibility of failure becomes low again, the power voltage can be supplied, which is preferable.

Here, the control unit determines that the power cable is defective if the calculated probability of failure exceeds a third predetermined value that is higher than the second predetermined value, and it is preferable to prevent an accident that may occur due to a failure of the power cable by cutting off the power supplied to the power cable.

And, the control unit stores the measures to be taken in case the first preset value, the second preset value and the third preset value are exceeded, and it is preferable to inform the user of the measures to identify the pattern of the power cable failure.

Here, it is preferable that the control unit can accurately identify the fault location determined to be a fault by determining the location of the power cable corresponding to the detection location of the detected optical signal as the fault location.

And the accuracy of the fault detection distance of the above fault location is up to 10 m, and it is desirable to have a range of ±5 m from the detection location of the detected optical signal, so that the fault location of the power cable can be easily found.

Here, the control unit preferably determines the detection location of the detected optical signal as a fault location when the detected optical signal deviates from the normal characteristics of the optical signal at the same time on multiple dates, so that the fault location determined to be a fault can be accurately identified.

And, if the time for which the detected optical signal deviates from the normal characteristics of the optical signal exceeds a predetermined time, the control unit determines that the power cable is defective, and the power cable continuously generates an acoustic signal for the defect after the defect occurs, so that if this is detected, the defect in the power cable can be accurately determined, which is preferable.

Meanwhile, a method for detecting a fault in a power cable using an optical cable according to the present invention for achieving the above object includes the steps of: arranging the optical cable adjacent to the power cable at a predetermined distance; supplying an optical signal to the optical cable; detecting an optical signal from the optical cable; determining whether the optical intensity, scattering, and frequency of the detected optical signal deviate from the normal characteristics of the stored optical signal; and, if it is determined that the detected optical signal deviates from the normal characteristics of the optical signal, calculating the possibility of a fault in the power cable according to the degree to which the detected optical signal deviates from the normal characteristics of the optical signal. Accordingly, when an optical cable is arranged adjacent to a power cable and the optical intensity, scattering, and frequency of the detected optical signal deviate from the normal optical intensity range, normal scattering range, and normal frequency range, the possibility of a fault can be calculated according to the degree to which the optical signal deviates. Therefore, a fault in the power cable can be accurately determined.

Here, the normal characteristics of the optical signal include at least one of a normal light intensity range, a normal scattering range, and a normal frequency range, and the step of determining whether at least one of the above is exceeded is preferably performed by sequentially determining whether, if the light intensity of the detected optical signal exceeds the normal light intensity range, the frequency of the detected optical signal exceeds the normal frequency range, and if so, whether scattering of the detected optical signal exceeds the normal scattering range, so that an accurate fault in the power cable can be determined.

And the step of calculating the possibility of a failure of the power cable includes the step of storing a failure change pattern of the optical intensity and frequency of the optical cable for a failure of the power cable; and the step of calculating the possibility of a failure of the power cable according to the similarity between the change pattern of the optical intensity and frequency of the optical signal detected from the optical signal detection unit and the failure change pattern, so that an accurate failure of the power cable can be determined, which is preferable.

Here, if the calculated probability of failure exceeds a first predetermined value, a step of transmitting the calculated probability of failure to a preset user terminal is further included, so that the user can be notified of the possibility of failure in the power cable, and thus preparations can be made in advance, which is desirable.

And, if the calculated probability of failure exceeds a second predetermined value that is higher than the first predetermined value, a step of supplying the voltage of the power supplied through the power cable at a second voltage that is at least lower than the first voltage currently supplied; and if the calculated probability of failure becomes lower than the second predetermined value again, a step of supplying the voltage of the power supplied through the power cable again at the first voltage is further included, so that if the probability of failure becomes higher, the power voltage can be adjusted to a lower value and if the probability of failure becomes lower again, the power voltage can be supplied at a normal power voltage, which is preferable.

Here, if the calculated probability of failure exceeds a third predetermined value that is higher than the second predetermined value, a step of determining that the power cable is faulty is further included, and if the step of determining that the power cable is faulty includes a step of cutting off power supplied to the power cable, it is preferable to prevent an accident that may occur due to a fault in the power cable.

And it is preferable to further include a step of storing the measures taken in case the first preset value, the second preset value and the third preset value are exceeded; and a step of notifying the user of the measures taken, so that a pattern of a power cable failure can be identified.

Here, it is preferable to further include a step of determining the location of the power cable corresponding to the detection location of the detected optical signal as the fault location, so that the fault location determined to be the fault can be accurately identified.

And, if the detected optical signal deviates from the normal characteristics of the optical signal at the same time on multiple dates, a step of determining the detection location of the detected optical signal as a fault location is further included, so that the fault in the power cable can be determined with certainty through accurate data step by step, which is preferable.

Here, if a step of determining that the power cable is defective is further included when the time for which the detected optical signal deviates from the normal characteristics of the optical signal exceeds a predetermined time, the power cable continuously generates an acoustic signal for the defect after the defect occurs, so that detecting this allows for an accurate determination of the defect in the power cable, which is preferable.

According to the present invention, when an optical cable is placed adjacent to a power cable and the optical intensity, scattering, and frequency of a detected optical signal deviate from the normal characteristics of the optical signal, including the normal optical intensity range, normal scattering range, and normal frequency range, the possibility of a failure can be calculated based on the degree of deviation, so that a failure in the power cable can be accurately determined, thereby reducing the cost and time for repairing the power cable.

Figure 1 is a simplified explanatory diagram of a power cable fault detection device according to the present invention.
Figure 2 is a graph of the scattering phenomenon of an optical fiber.
Figure 3 is a diagram explaining the occurrence of a fault in a power cable.
Figure 4 is a graph of light intensity when a fault occurs in a power cable.
Figure 5 is a graph of light scattering and frequency when a fault occurs in a power cable.
Figure 6 is a graph of the light intensity when power is continuously supplied after a power cable failure.
Figure 7 is a graph of light scattering and frequency when power is continuously supplied after a power cable failure.
Figure 8 is an example diagram for notifying a user of a power cable failure.
Figure 9 is a diagram explaining the location of a fault in a power cable.
Figures 10 and 11 are flowcharts of a power cable fault detection method.
Figure 12 is a flowchart illustrating a variation of power cable fault determination.
Figure 13 is a flowchart illustrating another variation of power cable fault determination.
Figure 14 is a control block diagram.

Hereinafter, a power cable fault detection device (1) according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a simplified explanatory diagram of a power cable fault detection device (1) according to the present invention, FIG. 2 is a graph of a scattering phenomenon of an optical fiber, FIG. 3 is an explanatory diagram of a fault occurrence in a power cable (2), FIG. 4 is a graph of light intensity when a fault occurs in a power cable (2), FIG. 5 is a graph of light scattering and frequency when a fault occurs in a power cable (2), FIG. 6 is a graph of light intensity when power is continuously supplied after a fault occurs in a power cable (2), FIG. 7 is a graph of light scattering and frequency when power is continuously supplied after a fault occurs in a power cable (2), FIG. 8 is an exemplary diagram for notifying a user of a fault occurrence in a power cable (2), FIG. 9 is an explanatory diagram of a location of a fault occurrence in a power cable (2), and FIG. 13 is a control block diagram.

A power cable (2) comprises a conductor made of a conductive material such as copper or aluminum, an inner semiconducting layer that surrounds the conductor and suppresses partial discharge at the interface with the conductor by eliminating an air layer between the conductor and the insulating layer, and alleviates local electric field concentration in the insulating layer, an insulating layer that surrounds the inner semiconducting layer, and an outer semiconducting layer that surrounds the insulating layer and performs the role of shielding the cable and ensuring that an electric field is applied evenly to the insulating layer.

In addition, the power cable (2) may further include a metal sheath and a polymer sheath wrapping the metal sheath on the outside of the outer semiconductive layer. Here, the materials and specifications of the conductor, inner semiconductive layer, insulating layer, outer semiconductive layer, metal sheath, and polymer sheath of the power cable (2) may vary depending on the purpose of the photoelectric composite cable, transmission voltage, etc.

The power cable fault detection device (1) includes an optical cable, an optical signal generator (20), an optical signal detection unit (30), a communication unit (40), a voltage stimulating unit (50), a display unit (60), a user input unit (70), and a control unit (80).

An optical cable is installed adjacent to one or more power cables (2) at a predetermined distance. The optical cable may include at least one optical fiber and a tube for accommodating the optical fiber. Each optical cable includes a predetermined number of optical fibers mounted together with a filler material within the tube, and the tube may be made of a rigid material such as stainless steel. The optical cable may further include a sheath surrounding the tube.

The optical signal generator (20) supplies an optical signal through an optical cable.

The optical signal detection unit (30) is connected to the optical cable and detects an optical signal supplied from the optical signal generator (20). The optical signal detection unit (30) can detect an acoustic signal transmitted through the optical cable when there is a fault in the power cable (2).

The communication unit (40) can transmit data to an external device and receive data.

The voltage booster (50) can supply voltage by regulating it through the power cable (2). The voltage booster (50) allows the voltage of the power cable (2) to be supplied by regulating it to high or low.

The display unit (60) is configured as a monitor and can display various images to the user. In particular, it can display graphs regarding light intensity, scattering, and frequency according to changes in the optical signal transmitted through the optical cable. In addition, it can display warnings to the user.

The user input unit (70) may be provided with a touch screen, a keyboard voice recognition device, a motion recognition device mouse, etc. to enable the user to input commands.

The control unit (80) stores the normal light intensity range, normal scattering range, and normal frequency range of the optical signal in the normal state of the power cable (2), and if it is determined that the optical signal detected from the optical signal detection unit (30) deviates from at least one of the normal light intensity range, the normal scattering range, and the normal frequency range, the control unit (80) calculates the possibility of a fault in the power cable (2) based on the degree to which the detected optical signal deviates from at least one of the normal light intensity range, the normal scattering range, and the normal frequency range.

If the light intensity of the detected light signal exceeds the normal light intensity range, the control unit (80) determines whether the frequency of the detected light signal exceeds the normal frequency range, and if so, sequentially determines whether the scattering of the detected light signal exceeds the normal scattering range.

The control unit (80) stores the failure change pattern of the optical intensity and frequency of the optical cable in response to a failure of the power cable (2), and calculates the possibility of failure of the power cable (2) based on the similarity between the change pattern of the optical intensity and frequency of the optical signal detected from the optical signal detection unit (30) and the failure change pattern.

The control unit (80) controls the communication unit (40) to transmit the calculated possibility of failure to a preset user terminal when the calculated possibility of failure exceeds a first predetermined value.

The control unit (80) supplies the voltage of the power supplied to the power cable (2) at a second voltage that is at least lower than the first voltage currently supplied when the calculated probability of failure exceeds a second predetermined value that is higher than the first predetermined value, and supplies the voltage of the power supplied to the power cable (2) at the first voltage again when the calculated probability of failure becomes lower than the second predetermined value again.

The control unit (80) determines that the power cable (2) is defective if the calculated probability of failure exceeds a third predetermined value that is higher than the second predetermined value.

If the control unit (80) determines that the power cable (2) is defective, it cuts off the power supplied to the power cable (2).

The control unit (80) stores the measures to be taken when the first preset value, the second preset value, and the third preset value are exceeded, and notifies the user of the measures. Here, the accuracy (resolution) of the fault detection distance of the fault location of the power cable (2) is at most 10 m, and the fault location has a range of ±5 m from the detection location of the detected optical signal.

The control unit (80) determines the position of the power cable (2) corresponding to the detection position of the detected optical signal as a fault position.

Here, the fault location of the power cable (2) is within a maximum of 10 m and has a range of ±5 m from the detection location of the detected optical signal. This solves the problem of having to dig in multiple locations as in the past.

The control unit (80) determines the detection location of the detected optical signal as a fault location when the detected optical signal deviates from at least one of the normal light intensity range, the normal scattering range, and the normal frequency range at the same time on multiple dates.

The control unit (80) determines that the power cable (2) is defective if the time for which the detected optical signal deviates from at least one of the normal light intensity range, the normal frequency range, and the normal scattering range exceeds a predetermined time.

Figure 2 is a graph of the scattering phenomenon of an optical fiber.

When an optical signal is transmitted through an optical cable, some of it is backscattered, and changes in the intensity and frequency of the returned light occur depending on changes in temperature, vibration, pressure, sound, etc. In particular, optical fibers/optical cables are being used as sensing cables to detect the health of various environments such as power/communication cables, gas pipelines, and railways due to external factors and aging, and optical cable technology can be used to detect defective points such as destruction of power cables (2).

Figure 3 is a diagram explaining the occurrence of a fault in a power cable (2).

Fig. 3 (a) A power cable (2) is in a state where a nail is driven into an arbitrary point to cause a fault.

Figure 3 (b) The voltage was slowly applied from 0 kV. At 10 kV and 20 kV, there was almost no change in the acoustic signal, and when 30 to 35 kV was applied, an arc occurred as the cable was destroyed.

Figure 4 is a graph of the optical intensity when a fault occurs in a power cable (2). The x-axis represents the cable distance, the y-axis represents time, and the intensity of the acoustic signal detected by the cable in real time is expressed in different colors.

In the case of Fig. 4, it was confirmed that a waterfall graph was generated widely as the arc vibration was propagated along the length of the cable at the initial point of destruction, and at this time, the frequency was confirmed to be 300 Hz and the light intensity was confirmed to be at most 5000.

Figure 5 is a graph of light scattering and frequency when a fault occurs in a power cable (2).

Fig. 5 (a) It can be seen that the scattered portion expands when a fault occurs in the power cable (2).

In Fig. 5 (b), it can be confirmed that the frequency value of the characteristic intensity increases in the FFT analysis graph when a fault occurs in the power cable (2).

Figure 6 is a graph of light intensity when power is continuously supplied after a power cable (2) failure occurs.

A voltage of approximately 5 kV was continuously applied, and it was confirmed that the fault detection section was less than 10 m, the frequency was 120 Hz, and the intensity was up to 3000.

Figure 7 is a graph of light scattering and frequency when power is continuously supplied after a power cable (2) failure occurs.

Fig. 7 (a) If voltage is continuously applied after the power cable according to Fig. 6 is broken, it can be confirmed that a waveform is periodically generated at the point of failure by an acoustic signal.

Fig. 7 (b) It can be confirmed that a frequency waveform of characteristic intensity is periodically generated in the FFT analysis graph in a state where voltage is continuously applied after the power cable according to Fig. 6 is broken.

Figure 8 is an example diagram that notifies the user of a power cable (2) failure.

When a fault occurs at any point in a power cable (2), the fault is detected, the fault probability is calculated, and the calculated fault probability information is transmitted to a preset user terminal. This allows the user to recognize the fault probability and utilize the detection signal to immediately devise a response plan, such as power cutoff.

Figure 9 is a diagram explaining the location of a fault in a power cable (2).

Even when the control unit (80) determines the location of a fault, the exact location cannot be determined. However, the fault location exists within 5 meters in front and behind the determined location. Previously, reliability in this area was low, and thus, significant time and cost were spent on excavation work to repair the fault, making it difficult to locate the fault location. However, the present invention can reliably locate the fault location within 5 meters in front and behind the determined location, saving time and money.

This explains a method for detecting faults in power cables (2) using optical cables.

Figures 10 and 11 are flowcharts of a method for detecting a fault in a power cable (2).

The optical cable is placed at a predetermined distance from the power cable (2) (S101).

An optical signal is supplied through an optical cable (S102).

Detect an optical signal from an optical cable (S103).

It is determined whether the light intensity, scattering, and frequency of the detected light signal are outside at least one of the stored normal light intensity range, normal scattering range, and normal frequency range (S104).

If it is determined that the detected optical signal is outside at least one of the normal light intensity range, normal scattering range, and normal frequency range, the possibility of failure of the power cable (2) is calculated based on the degree to which the detected optical signal is outside at least one of the normal light intensity range, normal scattering range, and normal frequency range (S105).

If the calculated failure probability exceeds the first preset value, the calculated failure probability is transmitted to a preset user terminal (S106).

If the generated failure probability exceeds the second predetermined value, which is higher than the first predetermined value, the voltage of the power supplied through the power cable (2) is supplied at a second voltage that is at least lower than the first voltage currently supplied (S107).

If the calculated failure probability becomes lower than the second preset value again, the voltage of the power supplied to the power cable (2) is supplied again at the first voltage (S108).

If the calculated failure probability exceeds the third predetermined value, which is higher than the second predetermined value, the power cable (2) is judged to be faulty (S109).

If the time for which the detected optical signal deviates from at least one of the normal light intensity range, normal frequency range, and normal scattering range exceeds a predetermined time, the power cable (2) is determined to be faulty (S120).

Power supplied through the power cable (2) is cut off (S121).

Store the measures to be taken in case the first, second and third sub-policies are exceeded (S122).

Notify the user of the action taken (S123).

The location of the power cable (2) corresponding to the detection location of the detected optical signal is determined as the fault location (S124).

If an optical signal detected at the same time on multiple dates deviates from at least one of the normal light intensity range, normal scattering range, and normal frequency range, the detection location of the detected optical signal is determined to be a fault location (S125).

Afterwards, the power cable (2) recovery team moves to the faulty location and performs recovery work.

Figure 12 is a flowchart illustrating a variation of a power cable (2) fault determination method.

The optical cable is placed at a predetermined distance from the power cable (2) (S201).

An optical signal is supplied through an optical cable (S202).

Detect an optical signal from an optical cable (S203).

If the light intensity of the detected light signal exceeds the normal light intensity range, it is determined whether the frequency of the detected light signal exceeds the normal frequency range, and if so, it is determined sequentially whether the scattering of the detected light signal exceeds the normal scattering range (S204).

Calculate the possibility of failure of the power cable (2) (S205).

Figure 13 is a flowchart showing another variation of the power cable (2) fault determination method.

The optical cable is placed at a predetermined distance from the power cable (2) (S301).

Supply optical signals through optical cables (S302).

Detect an optical signal from an optical cable (S303).

S-304 Determine whether the intensity, scattering, and frequency of the detected optical signal are outside at least one of the stored normal intensity range, normal scattering range, and normal frequency range.

The failure change pattern of the optical intensity and frequency of the optical cable in response to a failure of the power cable (2) is stored (S305).

The possibility of failure of the power cable (2) is calculated based on the similarity between the change pattern of the light intensity and frequency of the light signal detected from the light signal detection unit (30) and the failure change pattern (S306).

Describes embodiments that can be modified other than the above embodiments.

By continuously monitoring the power flow of a power cable (2), faults can be identified by linking them to changes in the optical signal of an optical cable. If a fault causes a change in the power flow, the change in the optical signal can also be detected. By considering the decrease in power transfer efficiency due to voltage changes in the power cable (2) and the change pattern of the optical signal, if the change exceeds a predetermined value, the possibility of a fault can be calculated and a fault can be identified.

By using the above power cable fault detection device (1) and the power cable (2) fault detection method using the same, when an optical cable is placed adjacent to a power cable (2), the possibility of a fault can be calculated based on the degree to which the optical intensity, scattering, and frequency of the detected optical signal deviate from the normal optical intensity range, normal scattering range, and normal frequency range, so that a fault in the power cable (2) can be accurately determined.

By sequentially comparing and judging the optical intensity, frequency, and scattering of the detected optical signal, the exact fault in the power cable (2) can be determined. The possibility of a fault in the power cable (2) can be calculated based on the similarity between the change pattern of the optical intensity, scattering, and frequency of the detected optical signal and the fault change pattern, thereby accurately judging the fault in the power cable (2). The calculated possibility of a fault can be transmitted to a preset user terminal to notify the user of the possibility of a fault in the power cable (2).

When the possibility of a failure increases, the power voltage is adjusted to a lower level and supplied, and when the possibility of a failure decreases again, the power can be supplied at the normal voltage. When a failure occurs, the power supplied to the power cable (2) is cut off, so that an accident that may occur due to a failure in the power cable (2) can be prevented. The measures taken in case the first, second, and third preset values are exceeded are stored and the measures are notified to the user, so that a pattern of failure in the power cable (2) can be identified. Alternatively, if it is determined that a failure is likely to occur, in an urgent case, the power can be immediately cut off and replaced with a spare cable to ensure a smooth power supply.

The location of the power cable (2) corresponding to the detection location of the detected optical signal is determined as the fault location, so the fault location can be accurately identified. The distance accuracy (resolution) of the fault point derived from the detected optical signal has a range of ±5 m, so the repair/restoration section of the power cable (2) is narrowed, thereby reducing the repair cost and time. If the optical signal detected at the same time on multiple dates deviates from at least one of the normal light intensity range, normal scattering range, and normal frequency range, the detection location of the detected optical signal is determined as the fault location, so the fault location determined as the fault can be accurately identified. Since the power cable (2) continuously generates an acoustic signal for the fault after a fault occurs, detecting this can accurately determine the fault in the power cable (2).

1: Fault detection device 2: Power cable
10: Optical cable 20: Optical signal generator
30: Optical signal detection unit 40: Communication unit
50: voltage supply section 60: display section
70: User input section 80: Control section

Claims (26)

In a power cable fault detection device using optical cables,
An optical cable arranged adjacent to the power cable at a predetermined distance;
An optical signal generator that supplies an optical signal to the optical cable;
An optical signal detection unit connected to the optical cable and detecting an optical signal supplied from the optical signal generator; and
A control unit storing the normal characteristics of the optical signal including the normal optical intensity range, normal scattering range and normal frequency range of the optical signal in the normal state of the power cable and the disturbance change pattern of the optical intensity and frequency of the optical cable in response to a disturbance of the power cable, and if the optical intensity of the detected optical signal exceeds the normal optical intensity range based on the optical signal detected from the optical signal detection unit, sequentially determining whether the frequency of the detected optical signal exceeds the normal frequency range, and if it exceeds, sequentially determining whether the scattering of the detected optical signal exceeds the normal scattering range, and if it is determined that the scattering of the detected optical signal exceeds the normal scattering range, calculating the possibility of a disturbance of the power cable according to the degree to which the detected optical signal deviates from the normal optical intensity range, normal scattering range and normal frequency range of the optical signal and the similarity of the change pattern of the optical intensity and frequency of the optical signal detected from the optical signal detection unit with the disturbance change pattern,
The above control unit,
A power cable fault detection device characterized in that it calculates the possibility of a fault when the power transmission efficiency decreases due to voltage change of the power cable and the frequency change pattern of the optical signal detected from the optical signal detection unit exceeds a predetermined value.
delete delete delete In the first paragraph,
It further includes a communication unit capable of transmitting data to an external device,
The above control unit,
A power cable fault detection device characterized in that the communication unit is controlled to transmit the calculated fault probability to a preset user terminal when the calculated fault probability exceeds a first predetermined value.
In paragraph 5,
It further includes a voltage booster that can supply voltage by regulating the voltage through the above power cable,
The above control unit,
A power cable fault detection device characterized in that, when the calculated probability of failure exceeds a second predetermined value that is higher than the first predetermined value, the voltage of the power supplied to the power cable is supplied at a second voltage that is at least lower than the first voltage currently supplied, and when the calculated probability of failure is lowered again than the second predetermined value, the voltage of the power supplied to the power cable is supplied again at the first voltage.
In paragraph 6,
The above control unit,
A power cable fault detection device characterized in that the power cable is determined to be faulty when the calculated fault probability exceeds a third preset value that is higher than the second preset value.
In paragraph 7,
The above control unit,
A power cable fault detection device characterized by cutting off power supplied through the above power cable.
In paragraph 8,
The above control unit,
A power cable fault detection device characterized in that it stores measures to be taken when the first preset value, the second preset value, and the third preset value are exceeded, and notifies the user of the measures.
In paragraph 6,
The above control unit,
A power cable fault detection device characterized in that the position of the power cable corresponding to the detection position of the detected optical signal is determined as a fault position.
In paragraph 10,
A power cable fault detection device characterized in that the fault detection distance accuracy of the above fault location is up to 10 m.
In paragraph 10,
A power cable fault detection device characterized in that the above fault location has a range of ±5 m from the detection location of the detected optical signal.
In the first paragraph,
The above control unit,
A power cable fault detection device characterized in that, when the detected optical signal deviates from the normal characteristics of the optical signal at the same time on multiple dates, the detection location of the detected optical signal is determined to be a fault location.
In the first paragraph,
The above control unit,
A power cable fault detection device characterized in that the power cable is determined to be faulty if the time for which the detected optical signal deviates from the normal characteristics of the optical signal exceeds a predetermined time.
In a method for detecting power cable faults using optical cables,
A step of arranging the optical cable adjacent to the power cable at a predetermined distance;
A step of supplying an optical signal through the optical cable;
A step of detecting an optical signal from the optical cable;
A step of storing the normal characteristics of the optical signal, including the normal optical intensity range, normal scattering range, and normal frequency range of the optical signal in the normal state of the power cable, and the disturbance change pattern of the optical intensity and frequency of the optical cable in response to a disturbance of the power cable;
A step of sequentially determining whether the frequency of the detected optical signal exceeds the normal frequency range when the optical intensity of the detected optical signal exceeds the normal optical intensity range, and if so, whether the scattering of the detected optical signal exceeds the normal scattering range;
A step of calculating the possibility of a fault in the power cable based on the degree to which the detected optical signal deviates from the normal optical intensity range, normal scattering range, and normal frequency range of the optical signal and the similarity of the change pattern of the optical intensity and frequency of the optical signal detected from the optical signal detection unit with the fault change pattern, if the scattering of the detected optical signal is determined to exceed the normal scattering range; and
A power cable fault detection method characterized by including a step of calculating a possibility of a fault when the power transmission efficiency decreases due to a voltage change of the power cable and the frequency change pattern of the optical signal detected from the optical signal detection unit exceeds a predetermined value.
delete delete delete In paragraph 15,
A power cable fault detection method, characterized in that it further includes a step of transmitting the calculated fault probability to a preset user terminal when the calculated fault probability exceeds a first predetermined value.
In paragraph 19,
A step of supplying the voltage of the power supplied to the power cable at a second voltage that is at least lower than the first voltage currently supplied when the generated probability of failure exceeds a second value that is higher than the first value; and
A power cable fault detection method characterized by further comprising a step of supplying the voltage of the power supplied to the power cable back to the first voltage when the calculated fault probability is again lower than the second predetermined value.
In paragraph 20,
A power cable fault detection method characterized in that it further includes a step of determining that the power cable is faulty when the calculated fault probability exceeds a third preset value that is higher than the second preset value.
In paragraph 21,
The steps for determining that the above power cable is defective are:
A power cable fault detection method characterized by including a step of cutting off power supplied to the power cable.
In paragraph 22,
A step of storing measures for cases where the first preset value, the second preset value, and the third preset value are exceeded; and
A power cable fault detection method characterized by further comprising a step of notifying a user of the above measures.
In paragraph 20,
A power cable fault detection method characterized by further comprising a step of determining a location of the power cable corresponding to the detection location of the detected optical signal as a fault location.
In paragraph 15,
A power cable fault detection method characterized by further comprising a step of determining a detection location of the detected optical signal as a fault location when the detected optical signal deviates from the normal characteristics of the optical signal at the same time on multiple dates.
In paragraph 15,
A power cable fault detection method characterized in that it further includes a step of determining that the power cable is faulty if the time for which the detected optical signal deviates from the normal characteristics of the optical signal exceeds a predetermined time.