KR100684741B1 - Apparatus and method of detecting partial discharge from a distribution line switchgear - Google Patents

Abstract

A device and a method for detecting partial discharge of a distribution line switchgear are provided to prevent the unnecessary power consumption of a detecting device by using a power measurement value for the entire frequency band as a driving signal. A device for detecting partial discharge of a distribution line switchgear is composed of a discharge sensor unit(310) detecting a discharge signal(301) generated from the switchgear; a power measuring unit(320) for generating discharge signals for each frequency band after dividing the discharge signal into plural frequency bands and generating a voltage signal correspondent to the magnitude of power of the discharge signal for each frequency band as a power measurement value(302); and a partial discharge judging unit(330) judging whether the partial discharge is detected, by comparing the power measurement value with a first critical value.

Description

Apparatus and method for detecting partial discharge in switchgear of distribution line {APPARATUS AND METHOD OF DETECTING PARTIAL DISCHARGE FROM A DISTRIBUTION LINE SWITCHGEAR}

1 is a graph illustrating an example of a frequency spectrum of partial discharge detected from a distribution line switchgear.

2 is a block diagram showing an example of an internal configuration of a conventional partial discharge detection device.

3 is a block diagram showing an internal configuration of a partial discharge detection apparatus according to an embodiment of the present invention.

FIG. 4 is a block diagram illustrating an internal configuration of a full band power measurement unit and a detection driver included in the embodiment of FIG. 3.

5 is a frequency spectrum graph illustrating the influence of the discharge signal by the wireless communication signal.

6 is a graph illustrating output waveforms of a log amplifier and a comparator included in the partial discharge detection apparatus according to an embodiment of the present invention.

7 is a block diagram illustrating a connection relationship between a high speed comparator and a zero crossing detector included in a partial discharge detection apparatus according to an exemplary embodiment of the present invention.

8 is a block diagram showing an internal configuration of a power measurement unit for each frequency band according to an embodiment of the present invention.

9 is a graph schematically showing a time relationship between a zero crossing point of a sine wave power signal and a generation point of a discharge signal.

10 is a flowchart illustrating a discharge signal detection method according to an embodiment of the present invention step by step.

FIG. 11 is a flowchart illustrating detailed steps included in measuring power for each frequency band in the embodiment of FIG. 10.

<Explanation of symbols for the main parts of the drawings>

301: discharge signal 302: power measurement value for each frequency band

303: full-band power measurement 304: detection drive signal

310: discharge sensor unit 320: power measurement unit for each frequency band

330: partial discharge determination unit 340: full-band power measurement unit

350: detection driver 401: filter signal

402: threshold 702: partial discharge time value

704: zero crossing time value

The present invention relates to an apparatus and method for detecting partial discharge occurring in a switchgear. More specifically, the present invention relates to an apparatus and a method for detecting and analyzing a partial discharge phenomenon based on a measured value of power for each frequency band of a discharge signal generated in an opening and closing device.

The importance of electrical energy cannot be overemphasized. Today, electrical energy is widely used in various industries. Such electrical energy is produced and transported through a system called Electric Power System.

Electrical energy produced in various types of power plants is delivered to the power distribution facilities through high-voltage power transmission facilities and substations, and the power distribution facilities supply the received electric energy back to each customer. Consumers use various electrical devices by using electrical energy supplied from distribution facilities through distribution lines.

The electrical energy produced at the power plant is transmitted as a high voltage signal to minimize the loss of transmission. However, high-voltage electrical signals ranging from tens to hundreds of kV along the transmission line are too high for each consumer to use and need to be converted to low-voltage signals that can be used in homes or factories.

Substations play this role. The substation is located between a transmission line and a distribution line, and converts a high transmission voltage into a low distribution voltage. The substation is equipped with a switchgear (Switchgear) for connecting or disconnecting the transmission line and the distribution line, this is called the distribution line switchgear. For reference, the term "distribution line switchgear" used in this specification may be interpreted to include all small switchgear devices installed in power distribution facilities connected through various branches in addition to large-scale switchgear devices installed in substations.

Distribution line switchgear is divided into inflow, magnetic, pneumatic, etc., and gas insulated switchgear (GIS) using SF6 gas having excellent insulation strength is widely used. However, even if it has excellent insulation performance, due to the characteristics of the power system, the ripple effect such as social disruption or economic loss caused by one insulation accident is so great that a thorough check is necessary to prevent insulation accidents.

In particular, the necessity of expanding transportation facilities due to the increase in power demand and the concentration of large cities is increasing, and the size and capacity of power facilities are increasing. However, manpower inspections of large-scale power plants scattered throughout are not only suitable for accident prevention checks that must be perfected, but are virtually impossible.

Accordingly, researches on a technique for automatically detecting a partial discharge phenomenon, which is the most representative cause of deterioration of a switchgear of a distribution line, have been widely conducted. Partial discharge (PD) is a discharge phenomenon that occurs locally along or around an insulator under high voltage stress. Partial discharges often occur in naturally formed physical voids or cracks that are partially cracked due to deterioration of the switchgear. However, the partial discharge phenomenon is invisible and various types are difficult to automate detection.

Partial discharges can lead to continuous power loss due to leakage of power, and when the effects accumulate, they can cause irreversible physical and chemical changes to the insulating material. This can lead to a complete shutdown of the power supply through the distribution lines or, in serious cases, to the explosion of the installation.

A commonly used method for analyzing the partial discharge phenomenon is to analyze the frequency spectrum of the discharge signal detected from the switchgear. 1 is a graph illustrating a frequency spectrum of a partial discharge detected from a switchgear switchgear. As shown in Fig. 1, the partial discharge phenomenon appears over a very wide frequency band of several hundred MHz to several GHz, and therefore, a large amount of calculation is required to analyze the frequency spectrum over such a wide band.

2 is a block diagram showing a general configuration of a conventional apparatus for detecting partial discharge. Referring to FIG. 2, the conventional partial discharge detection device includes a digital conversion unit 220 for converting the discharge signal 201 detected from the switchgear through the discharge sensor unit 210 into a digital signal for easy analysis. Include. The digitally converted discharge signal 202 is converted into a spectrum signal 203 in the frequency domain by the frequency domain converter 230 and input to the partial discharge detector 240 that determines whether or not the partial discharge is detected.

In general, a widely used device for converting a time domain signal into a frequency domain signal is a fast Fourier transformer. However, as noted, a significant amount of computation is required to fast Fourier transform a signal received over a wide band in a short time. In addition, a high performance digital signal processor (DSP) is required to analyze patterns appearing on the frequency spectrum of the discharge signal in comparison with various types of partial discharges.

Although it is possible to apply such expensive equipment to a relatively small number of power transmission facilities, it is impossible to apply it to a large number of power distribution facilities. In particular, low-cost power distribution facilities such as feeder remote terminal units (FRTUs) for power distribution automation have a relatively small ripple effect in the event of insulation accidents compared to power transmission facilities, so high-performance, high-cost partial discharge of all power distribution facilities is required. Installing a detection apparatus is a big burden.

Accordingly, the present invention is to solve the problems of the conventional partial discharge detection device and to propose a new partial discharge detection device and method that can be implemented at low cost and efficiently.

The present invention has been made to improve the prior art as described above, and an object thereof is to provide a low-cost partial discharge detection device by simplifying the configuration of a conventional partial discharge detection device.

In addition, an object of the present invention is to prevent unnecessary power waste of the detection apparatus due to the continuous operation by using the full-band power measurement value as a drive signal in detecting partial discharge.

In addition, an object of the present invention is to determine whether the partial discharge phenomenon is detected by using the power measurement value for each frequency band, to efficiently analyze and detect the partial discharge phenomenon appearing over a wide frequency band.

It is also an object of the present invention to reduce the hardware or software complexity of the detection device and to lower the cost of the device by detecting the partial discharge without the help of a hardware or software device for converting the discharge signal into the frequency domain signal.

In addition, an object of the present invention is to further improve the driving efficiency and detection performance of the detection apparatus by further utilizing the time value at the moment when the partial discharge is detected and the time value at the moment when the sign of the sinusoidal power supply voltage is inverted.

In order to achieve the above object and to solve the above-mentioned problems of the prior art, the partial discharge detection device according to the present invention, the discharge sensor for detecting the discharge signal generated in the switchgear, frequency band power measurement of the discharge signal And a partial discharge determining unit determining whether or not the partial discharge is detected based on the power measurement unit for each frequency band generating a value, and the power measurement value for each frequency band.

In particular, the partial discharge detection apparatus according to an embodiment of the present invention further comprises a full-band power measurement unit for generating a full-band power measurement value of the discharge signal, and a detection driver for generating a detection drive signal according to the full-band power measurement value; The partial discharge determining unit may determine whether the partial discharge is detected in response to the detection driving signal generated as described above.

In addition, the partial discharge detection method according to the present invention comprises the steps of generating a full-band power measurement value of the discharge signal generated in the switching device, by separating the discharge signal into a plurality of frequency band signals, to generate a plurality of frequency band power measurement values And if the full band power measurement is greater than a predetermined threshold value, determining whether or not partial discharge is detected based on a plurality of frequency band power measurement values.

Hereinafter, a partial discharge detection apparatus and method according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram showing an internal configuration of a partial discharge detection apparatus according to an embodiment of the present invention.

As shown in FIG. 3, the discharge signal detected by the discharge sensor 310 is input to the power measuring unit 320 and the full band power measuring unit 340 for each frequency band. The power measurement unit 320 for each frequency band measures the power for each frequency band of the discharge signal, and passes the power measurement value 302 for each frequency band to the partial discharge determination unit, and the partial discharge determination unit 330 for each frequency band. It is determined whether partial discharge is detected based on the power measurement value 302.

On the other hand, the full-band power measuring unit 340 measures the power over the entire frequency band from the discharge signal 301, the generated full-band power measurement value 303 is input to the detection driver 350 to detect the detection drive signal ( 304). The detection driving signal is used as a trigger signal for determining whether the partial discharge determining unit 330 is operated as described above. Thus, the detection driving signal may be determined in response to the detection driving signal, thereby preventing unnecessary power waste.

An internal configuration of each component of FIG. 3 will be described in more detail with reference to the accompanying drawings.

4 is a block diagram illustrating an internal configuration of the full-band power measurement unit 340 and the detection driver 350 shown in FIG. 3.

According to the embodiment illustrated in FIG. 4, the full band power measurement unit 340 may include a frequency rejection filter unit 410 and a log amplifier 420. The frequency removal filter unit 410 receiving the discharge signal 301 received from the discharge sensor 310 generates a filter signal 401 by removing a specific frequency component from the discharge signal 301.

5 is a graph schematically showing the influence of various wireless communication signals on the discharge signal on the frequency spectrum. As shown in Fig. 5, since the partial discharge phenomenon occurs over a wide frequency band of several hundred MHz to several GHz, it may be caused by a wireless signal of a cellular mobile communication band near 900 MHz or a PCS mobile communication band near 1.8 GHz. Will be affected.

Accordingly, the frequency rejection filter unit 410 removes the influence of the signals of the specific frequency band on the partial discharge detection. As an example, the frequency cancellation filter 410 may be configured to include a plurality of notch filters having sharp frequency selectivity. In addition to the cellular mobile communication band and the PCS mobile communication band shown in FIG. 5, signals such as a wireless internet frequency band, a portable internet frequency band, a satellite broadcasting frequency band, and a digital multimedia broadcasting frequency band may affect the partial discharge signal. . Accordingly, the frequency removal filter unit 410 may include a plurality of notch filters for removing respective frequency band components.

Referring back to FIG. 4, the filter signal 401 from which a specific frequency component is removed by the frequency rejection filter 410 is input to the log amplifier 420 which is an example of the voltage signal generator. The log amplifier 420 is an apparatus for amplifying and outputting a power value of an input signal in a log scale. The power proportional to the square of the voltage or current has a large difference between the signal of the noise level when no partial discharge occurs and the signal when the partial discharge occurs. Therefore, log scale is used to compare them properly.

For reference, decibels (dB) or decibel milliwatts (dBm), which are generally used for comparing power, are also logarithmic units of power. When using a logarithmic scale of power, a small difference between small, low-power signals is converted to a larger scale, and a large difference between a large, high-power signals is converted to a smaller, comparable scale, resulting in a wider range of power values. The comparison between each other becomes easy.

Another effect that can be obtained by amplifying the power on a logarithmic scale is the input signal of the comparator 430 that compares the full-band power measurement 303 with a predetermined threshold 402 to generate the detection drive signal 304. It is possible to limit the size of the to a certain level. That is, when the full-band power measurement value 303 corresponding to each of the noise level signal when the partial discharge does not occur and the signal when the partial discharge occurs, is converted to a logarithmic scale and input to the comparator 430, a limited comparator ( 430 has the advantage that it is easier to be included in the range of the input voltage.

In the present embodiment, the log amplifier is illustrated in consideration of the advantage of using the power value of the logarithmic scale, but the voltage signal generator included in the full-band power measurement unit is a full-band voltage signal having a value corresponding to the full-band power magnitude of the discharge signal. Any type of amplifier, transformer, or any of a variety of filters that can be generated as power measurements can be included. In other words, the voltage signal generator may include all means for converting the power value of the discharge signal into a voltage value input to the comparator.

According to an embodiment of the present invention, the comparator 430 included in the detection driver 350 may generate the detection driving signal 304 when the full band power measurement value 303 is larger than the threshold 402. . Accordingly, in FIG. 4, the full-band power measurement value 303 is input to the (+) terminal of the comparator 430, and the threshold 402 is input to the (-) terminal. However, the connection relationship between the positive terminal and the negative terminal of the comparator 430 may be changed depending on the interface configuration of the partial discharge determining unit to which the detection driving signal 304 generated from the output of the comparator is input. For example, when the interface circuit of the partial discharge determining unit is operated by an active low interrupt, the full-band power measurement value 303 is connected to the negative terminal of the comparator, unlike that shown in FIG. 402 may be connected to a positive terminal. Alternatively, the meaning that the full band power measurement 303 is " greater than " the threshold 402 can be broadly interpreted as meaning that the magnitude of the signal, i.e., the amplitude to absolute value, is greater.

6 is a graph illustrating the output waveforms of the log amplifier 420 and the comparator 430 described above for each type of partial discharge. The four partial discharges PD1, PD2, PD3, and PD4 shown in FIG. 6 differ in power of the discharge signal over the entire band. That is, referring to the discharge signal shown in FIG. 6, partial discharge PD1 has -50 dBm, PD2 has -30 dBm, PD3 has -10 dBm, and PD4 has a full band power value of 0 dBm.

Referring to the figure, the log amplifier output values are 0 V for the discharge signal of the noise level when no partial discharge occurs, whereas -0.2 V, -0.5 V, and -1.2 V for the partial discharge PD1 to PD4, respectively. , And -2.1 V. That is, FIG. 6 illustrates a case where a log amplifier outputs a lower voltage as the full band power of the discharge signal is larger. It can also be seen from the graph that the log amplifier output is approximately linearly related to the full-band power value in dBm of the discharge signal.

Referring back to the graph of FIG. 6, the comparator output waveform when the log amplifier output is input to the comparator is shown below the log amplifier output waveform. It can be seen that the comparator output is not asserted with respect to the discharge signal of the noise level obtained when the partial discharge does not occur, but is asserted with respect to the discharge signal when the partial discharge occurs. When the effects of partial discharge disappear again, the comparator output waveform is de-asserted. As described above, since the output voltage of the comparator is distinct from the case where the partial discharge occurs, otherwise, the comparator output voltage waveform may be used as the detection driving signal 304 of the partial discharge determiner 330.

According to another embodiment of the present invention, the partial discharge detection apparatus may further include a generation time information extracting unit for extracting time information when the partial discharge occurred. 7 is a block diagram showing an internal configuration of a generation time information extracting unit.

According to the present embodiment, the generation time information extracting unit receives a sinusoidal power signal and detects a time value at a moment when a sign of the voltage value of the sinusoidal power signal is inverted (Zero-crossing Point). 720 and a high-speed comparator 710 for comparing the full-band power measurement with a predetermined threshold to detect a time value at the moment when the power measurement becomes greater than the threshold.

Referring to FIG. 7, the high speed comparator 710 compares the above-mentioned full-band power measurement value 303 with a threshold voltage 701 and the instant the output value is asserted, or the rising or falling edge of the output waveform. The time corresponding to is output as the partial discharge time value 702.

Although the absolute value of the partial discharge time value 702 has its own meaning in detecting the partial discharge, if the relative value based on the power signal waveform can be extracted in relation to the partial discharge occurrence time, the type of the partial discharge is determined. It can be used as more useful information to detect and detect the occurrence of partial discharge.

Therefore, the zero crossing detector 720 detects the zero crossing time value 704 which is the time when the sinusoidal power supply signal 703 crosses the reference voltage 0V and inputs it to the detection driver.

The detection driver 350 generates the detection driving signal 304 by referring to the partial discharge time value 702 input from the high speed comparator 710 and the zero crossing time value 704 input from the zero crossing detector 720. Can be determined.

In addition, although not shown in the drawings, the partial discharge time value 702 and the zero crossing time value 704 may be input to the partial discharge determiner 330 to be used for type analysis and occurrence detection of the partial discharge.

8 is a graph schematically showing a time relationship between a zero crossing point of the sine wave power signal 703 and a generation point of the discharge signal 301. As shown in FIG. 8, the partial discharge time value 702, which is information on occurrence time of partial discharge, which can be detected from the variation of the discharge signal power value, is based on the zero crossing time value 704 t ₀ of the sinusoidal power signal. can be expressed in relative time values t ₁ and t _2, thus indicated t ₁ and t ₂ are of detecting a partial discharge by detecting driving part 350 or the partial discharge determination unit 330, and and PD, as described above Can be used to analyze the type.

The internal configurations of the full-band power measurement unit 340 and the detection driver 350 among the components of the partial discharge detection device illustrated in FIG. 3 have been described in detail with reference to FIGS. 4 to 8. In summary, the detection driver 350 controls the operation of the partial discharge determination unit 330 based on the full-band power measurement value 303 measured by the full-band power measurement unit 340. Create That is, before the partial discharge determining unit 330 starts a series of calculation processes for determining whether the partial discharge has been detected, the partial discharge determination unit 330 refers to the full-band power measurement value 303 including a relatively simple calculation process. The discharge determination unit 330 may prevent unnecessary power waste of the detection device due to the continuous operation.

In addition, according to the range of the full-band power measurement value 303, the partial discharge determination unit 330 selectively applies a more likely determination operation method among the plurality of determination calculation methods, thereby improving efficiency and efficiency of the partial discharge determination unit 330. It can improve performance.

FIG. 9 is a block diagram illustrating an internal configuration of the power measuring unit 320 for each frequency band among the components of the partial discharge detection apparatus illustrated in FIG. 3.

The frequency band-specific power measuring unit 320 is a frequency selector 910 for generating a frequency band-specific discharge signal 901 from the discharge signal 301 and a frequency band-specific power measurement value ( The voltage signal generator 920 generating the 302 may be included.

The frequency selector 910 generates a plurality of frequency band discharge signals 901 by separating the discharge signal 301 for each frequency band. As an example, the frequency selector 910 may include a plurality of band pass filters or a plurality of correlators provided for each frequency band to be selected.

The frequency of the pass band of the plurality of band pass filters or the correlation input waveform of the plurality of correlation calculators can be adjusted by separate adjusting means. As an example, a user adjustment unit may be included to be adjustable by a user's setting, and may be adjusted according to a value calculated by referring to a power measurement value for each frequency band accumulated and stored for a certain period in the past. To this end, the partial discharge detection apparatus according to the present embodiment may further include a measurement value storage unit.

The plurality of frequency band discharge signals 901 may be converted into a voltage signal corresponding to the power of each frequency band by the voltage signal generator 920 and output. To this end, the voltage signal generator 920 may include a log amplifier 420 as included in the full-band power measurement unit 340. According to such a configuration, the power measurement value for each frequency band is amplified by a voltage of a logarithmic scale.

The voltage signal generator 920 may include a plurality of log amplifiers corresponding to each of the plurality of frequency band discharge signals 901. In this configuration, power measurement values for each frequency band can be simultaneously generated for each frequency band, thereby enabling fast partial discharge detection.

Alternatively, the voltage signal generator 920 may generate a plurality of frequency band power measurement values 302 from the plurality of frequency band discharge signals 901, for example, a number less than the number of frequency band discharge signals. It may include one log amplifier as. In this configuration, while the generation time of the power measurement value 302 for each frequency band is long, there is an advantage that the device can be configured using a smaller amount of hardware or software resources, and furthermore, the frequency selector 910 It is possible to operate flexibly even when the number of frequency bands selected by.

When the voltage signal generator 920 includes one log amplifier, the output power measurement values 302 for each frequency band may be sequentially output through one conductor, and alternatively, simultaneously, through a plurality of conductors. May be

The plurality of frequency band-specific power measurement values 302 generated as described above are input to the partial discharge determining unit 330. Although the predetermined detection determination criteria, for example, the threshold value, used in the partial discharge determining unit 330 for comparison with the power measurement value 302 for each frequency band is generally fixed at the time of shipment of the partial discharge detection device, It may be determined based on the detection determination data input from the user.

Alternatively, the detection criterion may be automatically determined based on a power measurement value for each frequency band accumulated in a predetermined period. To this end, the detection apparatus may further include a measurement value storage unit for accumulating and storing power measurement values for each frequency band.

Meanwhile, the discharge sensor unit 310 illustrated in FIG. 3 may include an amplification means for low noise amplifying the discharge signal 301. If the discharge signal is small, an appropriate pre-amplification process is required to measure the power of the full band and the frequency band. Accordingly, the discharge sensor 310 may amplify the discharge signal in advance by providing a low noise amplifier as an example of the amplifying means. For reference, when a low noise amplifier is used, noise components included in a small discharge signal may not be amplified together, which may result in a kind of noise filtering effect.

The partial discharge detection apparatus according to the present invention has been described above with reference to FIGS. 3 to 9. As described, the partial discharge detection apparatus according to the present invention may not include an expensive device as a component for converting a discharge signal into a signal in a frequency domain and analyzing a spectral signal of a wide frequency band obtained as a result of the distribution. It has a more suitable configuration for the furnace switchgear.

However, the present invention can be applied to power generation and transmission facilities, and the cost reduction effect obtained when the present invention is applied to such facilities and replaces the conventional partial discharge detection apparatus of a complicated structure is a person skilled in the art to which the present invention belongs. Self-explanatory

10 is a flowchart illustrating a discharge signal detection method according to an embodiment of the present invention step by step. Hereinafter, the plurality of steps illustrated in FIG. 10 will be described in detail for each step.

In operation S1010, a full band power measurement value is generated by measuring the full band power of the discharge signal detected by the switchgear. Step S1010 includes removing signals of specific frequency bands used for wireless communication among the wide bands in which partial discharge appears, and generating a voltage signal corresponding to the power magnitude of the discharge signal as a full band power measurement value. can do. For reference, a second step of the above-described steps may include amplifying or converting the full-band power value of the linear scale into the power value of the logarithmic scale.

In operation S1020, the discharging signal is divided into signals for each frequency band to generate a plurality of power measurement values for each frequency band. The detailed steps included in step S1020 are shown in FIG. 11. As shown in FIG. 11, step S1020 may be performed by dividing a discharge signal into signals for each frequency band (S1110), and generating a voltage signal corresponding to the power magnitude of the signal for each frequency band as a power measurement value for each frequency band. It may include the step (S1120).

As in the case of step S1010, step S1120 includes amplifying or converting a power value for each frequency band of a linear scale into a power value of a logarithmic scale to generate a corresponding voltage signal as a power measurement value for each frequency band. can do. The plurality of frequency band power measurements may be generated by sequentially performing the step S1120 for each of the plurality of frequency band discharge signals sequentially or in parallel.

Steps S1010 and S1020 may be performed sequentially or simultaneously with each other.

Step S1030 is a step of determining whether a partial discharge is detected by referring to the power measurement value for each frequency band generated by step S1020. However, as shown in FIG. 11, step S1030 is performed according to a comparison result performed on the full band power measurement value obtained by step S1010 and a predetermined threshold value.

For reference, FIG. 11 illustrates only the case where step S1030 is performed when the full-band power measurement is larger than the threshold, but the power measurement is thresholded according to the sign of the full-band power measurement and the method of determining whether partial discharge is detected. It may also be configured to perform step S1030 if it is smaller than the value.

According to still another embodiment of the present invention, the partial discharge detection method shown in FIG. 10 includes receiving a sinusoidal power signal and detecting a time value at the instant when the sign of the voltage value of the power signal is inverted, and measuring a full band power. The method may further include detecting a time value at the instant when the value becomes larger than the threshold value. At this time, the step of determining whether the partial discharge is detected (S1030) may refer to the two time values obtained by the above two steps.

The partial discharge detection method according to the present embodiment has been described so far, and the foregoing descriptions relating to the embodiments of FIGS. 3 to 9 can be applied to the present embodiment as it is. It will be omitted.

The partial discharge detection method according to the present invention can be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on the media may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks such as floppy disks. -Magneto-Optical Media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. The medium may be a transmission medium such as an optical or metal wire, a waveguide, or the like including a carrier wave for transmitting a signal specifying a program command, a data structure, or the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

In the present invention as described above has been described by the specific embodiments, such as specific components and limited embodiments and drawings, but this is provided to help a more general understanding of the present invention, the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations are possible from such description.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and all the things that are equivalent to or equivalent to the claims as well as the following claims will belong to the scope of the present invention. .

According to the present invention, it is possible to simplify the configuration of the conventional partial discharge detection device to lower the cost of the detection device, thereby providing a configuration of the detection device more suitable for the power distribution equipment.

In addition, the detection apparatus according to the present invention can prevent unnecessary power waste of the detection apparatus due to the continuous operation by using the full-band power measurement value as the drive signal in detecting the partial discharge.

In addition, the detection apparatus according to the present invention can efficiently analyze and detect the partial discharge phenomenon appearing over a wide frequency band by determining whether the partial discharge phenomenon is detected using the power measurement value for each frequency band.

In addition, the detection apparatus according to the present invention can reduce the hardware or software complexity of the detection apparatus by detecting the partial discharge without the help of hardware or software components for converting the discharge signal into the frequency domain signal.

Further, according to the present invention, it is possible to further improve the driving efficiency and detection performance of the detection apparatus by further utilizing the time value at the moment when the partial discharge is detected and the time value at the moment when the sign of the sinusoidal power supply voltage is inverted.

In addition, according to an embodiment of the present invention, by using a set value input from a user or a cumulatively stored power measurement value as a criterion of detection or not, more adaptive partial discharge according to the environment of a power facility is enabled. .

In addition, according to an embodiment of the present invention, by performing a pre-processing process to remove the influence of the wireless mobile communication frequency band included in the frequency band in which the partial discharge phenomenon, it is possible to improve the partial discharge detection performance.

Claims (20)

In the device for detecting partial discharge of the switchgear of the distribution line, A discharge sensor unit for detecting a discharge signal generated by the switchgear; A frequency for generating the discharge signals for each of the plurality of frequency bands by separating the discharge signals for each of the plurality of frequency bands, and generating a voltage signal corresponding to the magnitude of power of the plurality of frequency bands for the discharge signal as the power measurement value for each frequency band Band-specific power measurement unit; A partial discharge determining unit determining whether the partial discharge is detected by comparing the power measurement value for each frequency band with a first threshold value; Partial discharge detection device comprising a. The method of claim 1, A full band power measurement unit for generating a full band power measurement value of the discharge signal; And A detection driver that compares the full band power measurement with a predetermined second threshold and generates a detection drive signal when the full band measurement is greater than the second threshold More, The partial discharge determining unit determines whether the partial discharge is detected in response to the generated detection driving signal. Partial discharge detection device, characterized in that. The method of claim 2, The full band power measuring unit, A voltage signal generator for generating a voltage signal corresponding to the magnitude of the full band power of the discharge signal as the full band power measurement value; Partial discharge detection apparatus comprising a. The method of claim 3, And the voltage signal generator comprises a log amplifier converting the magnitude of the full band power to a log scale and outputting the log signal. The method of claim 3, The full-band power measurement unit further includes a frequency removal filter unit for generating a filter signal by removing a signal of a specific frequency band from the discharge signal, Wherein the voltage signal generator generates the voltage signal from the filter signal Partial discharge detection device, characterized in that. The method of claim 5, The specific frequency band is a partial discharge detection device comprising at least one of a mobile communication frequency band, a wireless Internet frequency band, a portable Internet frequency band, a satellite broadcasting frequency band, and a digital multimedia broadcasting frequency band. delete The method of claim 2, A zero crossing detector configured to receive a sinusoidal power signal and detect a first time value at the moment when the sign of the voltage value of the sinusoidal power signal is inverted; And A high speed comparator that compares the full-band power measurement with a predetermined threshold and detects a second time value at the moment when the power measurement becomes greater than the threshold More, The detection driver generates the detection driving signal with reference to the first time value and the second time value. Partial discharge detection device, characterized in that. delete The method of claim 1, The voltage signal generator includes a log amplifier for converting the magnitude of the power for each frequency band to a log scale for outputting. The method of claim 1, A measurement value storage unit for accumulating and storing the power measurement values for each frequency band; More, The partial discharge determining unit determines whether the partial discharge is detected in consideration of the stored power measurement value for each frequency band. Partial discharge detection device, characterized in that. delete delete The method of claim 1, And the discharge sensor unit comprises amplifying means for low noise amplifying the discharge signal. The method of claim 1, Generation time information extraction unit for generating generation time information of the partial discharge More, The generation time information extraction unit, A zero crossing detector configured to receive a sinusoidal power signal and detect a first time value at the moment when the sign of the voltage value of the sinusoidal power signal is inverted; And A high speed comparator that compares the full-band power measurement with a predetermined threshold and detects a second time value at the moment when the power measurement becomes greater than the threshold Generating the first time value and the second time value as the generation time information; Partial discharge detection device, characterized in that. Generating a full band power measurement value of a discharge signal generated in the switchgear; Separating the discharge signal into a plurality of frequency band-specific signals to generate a plurality of power band-specific power measurements; And Determining whether the partial discharge is detected based on the power measurement values for each of the plurality of frequency bands when the full-band power measurement value is larger than a predetermined threshold value. Partial discharge detection method of the switchgear comprising a. The method of claim 16, Generating the full band power measurement, And generating a voltage signal corresponding to the power magnitude of the discharge signal as the full-band power measurement value. The method of claim 16, Generating the power measurement value for each frequency band, Separating the discharge signal into a plurality of frequency band-specific signals; And Generating a voltage signal corresponding to a power magnitude of the signal for each frequency band as the power measurement value for each frequency band; Partial discharge detection method comprising a. The method of claim 16, Receiving a sinusoidal power signal and detecting a first time value at the moment when the sign of the voltage value of the power signal is inverted; And Detecting a second time value at the moment when the full band power measurement becomes greater than the threshold value; More, The determining of whether the partial discharge is detected may refer to the first time value and the second time value. Partial discharge detection method characterized in that. A computer-readable recording medium having recorded thereon a program for executing the method according to any one of claims 16 to 19.

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