KR20180032962A - Apparatus and method for diagnosing measuring partial discharge - Google Patents

Abstract

The present invention relates to an apparatus and method for diagnosing partial discharge. To this end, the apparatus for diagnosing partial discharge according to one aspect of the present invention comprises a signal receiving part for receiving the ultrasonic signal of power equipment; and a partial discharge signal detection part for discriminating a noise signal and a partial discharge signal by analyzing the ultrasonic signal and determining that the partial discharge is generated in the power equipment when the partial discharge signal is detected. The partial discharge signal detection part calculates the rise time of the ultrasonic signal and classifies a signal which has the rise time of the ultrasonic signal less than the partial discharge determination time as a partial discharge signal. It is possible to detect only the partial discharge signal when detecting the partial discharge generated in the power equipment.

Description

[0001] APPARATUS AND METHOD FOR DIAGNOSING MEASURING PARTIAL DISCHARGE [0002]

The present invention relates to an apparatus and method for detecting a partial discharge, and more particularly, to an apparatus and a method for detecting and detecting only a pure partial discharge signal when detecting a partial discharge occurring in a power facility.

In the case of a power facility such as a GIS, a partial discharge signal may be generated due to deterioration due to equipment or long-term use. Generally, the following methods are conventionally used for the partial discharge diagnosis.

First of all, in the case of the on-line and portable partial discharge diagnosis systems of the prior art, the partial discharge signal is acquired from the electric power facility, and the partial discharge is diagnosed by accumulating the electromagnetic pulse peak hold value in the UHF band (0.3 to 3 GHz) . This method can determine the defect per partial discharge signal type by analyzing the peak hold accumulated value.

In addition, the conventional partial discharge signal diagnosis system is a technique of determining a partial discharge type by acquiring a partial discharge signal from a power facility through a UHF sensor and using a neural network built in the system. Such a partial discharge signal diagnosis system can perform a fault judgment with a pulse type external noise peak hold value (partial discharge signal < noise).

However, such a conventional partial discharge diagnostic technique has a problem that the diagnosis accuracy is low, in which a defect judgment error occurs even though an insulator partial discharge signal is judged as a particle or an actual partial discharge occurs. In addition, there may be a case where a signal used for determining the partial discharge occurrence position is tracked by a signal rather than a partial discharge signal generated in the GIS. In this case, there is a problem that accurate diagnosis of the partial discharge is difficult.

In addition, when the pattern of the partial discharge is recognized through the peak hold analysis of the partial discharge signal, the recognition rate of the partial discharge pattern is lowered and the analysis effect of the defect signal is insufficient.

Accordingly, there is a need for a new partial discharge diagnostic technique capable of detecting only a partial partial discharge signal when detecting a partial discharge occurring in a power facility and determining the partial discharge signal.

Korean Patent Laid-Open Publication No. 2013-0011176 (entitled "Ultra-high frequency partial discharge sensor for inflow transformer"

An object of the present invention is to provide an apparatus and method for detecting and detecting only a pure partial discharge signal when detecting a partial discharge generated in a power facility.

According to an aspect of the present invention, there is provided a partial discharge diagnostic apparatus including: a signal receiving unit for receiving an ultrasonic signal of a power facility; And a partial discharge signal detector for discriminating a noise signal from the partial discharge signal by analyzing the ultrasound signal and determining that a partial discharge has occurred in the power facility when the partial discharge signal is detected, And the signal whose rising time of the ultrasonic signal is less than the partial discharge judgment time is divided into partial discharge signals.

Also, the partial discharge signal detector may divide the signal whose rising time is equal to or longer than the partial discharge judgment time into a noise signal.

Also, the partial discharge diagnosis apparatus according to an embodiment of the present invention calculates a first peak voltage and a second peak voltage in a partial discharge signal when a partial discharge signal is detected, and generates a first peak voltage and a second peak voltage, And a damping ratio analyzing unit for calculating the damping ratio.

The partial discharge diagnosis apparatus may further include a resonance frequency calculation unit for calculating a resonance frequency based on a damping ratio between the first peak voltage and the second peak voltage.

Further, the resonance frequency calculation unit

(Equation)

(Where t _d is the time between the first peak and the second peak in the partial discharge signal, and? Is the damping ratio between the first peak voltage and the second peak voltage).

The partial discharge diagnosis apparatus according to an embodiment of the present invention may further include a partial discharge type determination unit that determines the type of the partial discharge based on the magnitude of the resonance frequency.

Further, the partial discharge type determination section can determine the type of the partial discharge by at least one of a corona defect, an insulator defect, a particle defect, a floating defect and an external noise according to the magnitude of the resonance frequency.

The partial discharge signal detector may include a filter module for detecting a signal in the range of 0.3 GHz to 3 GHz and the partial discharge signal detector may distinguish the noise signal from the partial discharge signal by analyzing ultrasonic signals in the range of 0.3 GHz to 3 GHz .

According to an aspect of the present invention, there is provided a method of diagnosing a partial discharge according to an embodiment of the present invention, comprising: receiving an ultrasonic signal of a power facility by a signal receiving unit; Separating the noise signal and the partial discharge signal by analyzing the ultrasonic signal by the partial discharge signal detection unit; And determining that a partial discharge has occurred in the electric power facility when the partial discharge signal is detected by the partial discharge signal detecting unit, wherein the step of distinguishing between the noise signal and the partial discharge signal includes calculating a rise time of the ultrasonic signal ; And dividing a signal whose rising time of the ultrasonic signal is less than the partial discharge judgment time into partial discharge signals.

The step of distinguishing between the noise signal and the partial discharge signal may further include the step of dividing the signal whose rise time is equal to or longer than the partial discharge judgment time into the noise signal.

Further, the partial discharge diagnosis method according to an embodiment of the present invention includes the steps of: calculating a first peak voltage and a second peak voltage in a partial discharge signal when a partial discharge signal is detected by a damping ratio analysis unit; And calculating a damping ratio between the first peak voltage and the second peak voltage by the damping ratio analyzing unit.

The method for diagnosing a partial discharge according to an embodiment of the present invention may further include calculating a resonance frequency based on a damping ratio between a first peak voltage and a second peak voltage by a resonance frequency calculator.

The step of calculating the resonance frequency based on the damping ratio between the first peak voltage and the second peak voltage

(Equation)

(Where t _d is the time between the first and second peaks in the partial discharge signal, and? Is the damping ratio between the first peak voltage and the second peak voltage).

The partial discharge diagnosis method according to an embodiment of the present invention may further include determining, by the partial discharge type determination unit, the type of the partial discharge based on the magnitude of the resonance frequency.

The step of determining the type of partial discharge based on the magnitude of the resonant frequency can also be performed by determining the type of partial discharge with at least one of corona defects, insulator defects, particle defects, floating defects, and external noises depending on the magnitude of the resonance frequency have.

According to another aspect of the present invention, there is provided a method of detecting a partial discharge, the method including detecting a signal in a 0.3 GHz to 3 GHz band by a partial discharge signal detecting unit, and analyzing an ultrasound signal to detect a noise signal and a partial discharge signal The separating step may be performed by analyzing ultrasonic signals in the 0.3 GHz to 3 GHz band.

According to the apparatus and method for detecting partial discharge of the present invention, it is possible to accurately diagnose whether or not a partial discharge is caused by detecting only a partial discharge signal when detecting a partial discharge occurring in a power facility. That is, a partial discharge signal generated in a power equipment, for example, a power device operating at 154 kV or more may have various defects. If a diagnosis is made through the partial discharge diagnosis apparatus and method according to an embodiment of the present invention, There is an effect that can accurately diagnose.

Also, according to the apparatus and method for detecting partial discharge of the present invention, it is possible to judge a defect of a detected partial discharge signal by type and to appropriately set countermeasures by applying an accurate defect determination algorithm.

Also, according to the apparatus and method for detecting partial discharge of the present invention, it is possible to more accurately verify the diagnosis result of the partial discharge by extracting the signal of each frequency region of the spectrum and analyzing the frequency characteristic of each frequency region.

In addition, according to the apparatus and method for detecting partial discharge of the present invention, various operations for analyzing a partial discharge can be performed in synchronization with a reference time so that a partial discharge can be accurately analyzed based on a signal detected at the same time.

Further, according to the apparatus and method for detecting partial discharge of the present invention, it is possible to more accurately prevent occurrence of partial discharge and detect the occurrence position, thereby preventing deterioration and failure due to defects of the power equipment.

1 is a block diagram of a partial discharge diagnosis apparatus according to an embodiment of the present invention.
2 is a block diagram of a partial discharge signal detector according to an embodiment of the present invention.
3 is a graph for explaining the concept of a rise time of an ultrasonic signal detected through a partial discharge signal detecting unit according to an embodiment of the present invention
4 is a block diagram of a damping ratio analysis unit according to an embodiment of the present invention.
5 is a graph illustrating a first peak voltage and a second peak voltage analyzed by the damping ratio analyzing unit according to an embodiment of the present invention.
FIG. 6 is a graph illustrating a damping ratio between a first peak voltage and a second peak voltage detected through a damping ratio analysis unit according to an embodiment of the present invention. Referring to FIG.
7 is a flowchart illustrating a partial discharge diagnosis method according to an embodiment of the present invention.

The present invention will now be described in detail with reference to the accompanying drawings. Hereinafter, a repeated description, a known function that may obscure the gist of the present invention, and a detailed description of the configuration will be omitted. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity.

Hereinafter, the partial discharge diagnostic apparatus 100 according to the embodiment of the present invention will be described.

1 is a block diagram of a partial discharge diagnosis apparatus 100 according to an embodiment of the present invention. Analysis of various RF (Radio Frequency) signals measured through a UHF (ultra high frequency) sensor can be used to analyze frequency band characteristics. By using these characteristics, the partial discharge signal and the external noise can be removed by analyzing the time difference between the frequency and the rise time of the pulse. Accordingly, the partial discharge diagnosis apparatus 100 according to an embodiment of the present invention diagnoses partial discharge by analyzing ultrasonic waves using the above-described characteristics.

The partial discharge diagnosis apparatus 100 according to an embodiment of the present invention includes a signal receiving unit 110, a partial discharge signal detecting unit 120, a damping ratio analyzing unit 130, a resonance frequency calculating unit 140, And a type determining unit 150 as shown in FIG. In order to facilitate understanding of the present invention, the above-described configurations are divided into functions, and the present invention can be realized through a single processing unit such as a CPU, MPU, and GPU. Referring now to FIG. 1, a description is given of a partial discharge diagnostic apparatus 100 according to an embodiment of the present invention.

The signal receiving unit 110 functions to receive ultrasonic signals of a power facility. As described above, when the partial discharge is present, the ultrasound signals of the power facilities received through the signal receiving unit 110 are analyzed in a frequency manner, and the signals for the partial discharge are divided into different bands (for example, 0.3 To 3 GHz). Accordingly, the partial discharge diagnostic apparatus 100 according to an embodiment of the present invention receives the ultrasound signal of the power facility through the signal receiving unit 110 and analyzes the ultrasound signal through the following configurations, Can be diagnosed.

The partial discharge signal detector 120 separates the noise signal and the partial discharge signal by analyzing the ultrasound signal received through the signal receiver 110. When the partial discharge signal is detected through the signal analysis, the partial discharge signal detector 120 can determine that a partial discharge has occurred in the corresponding electric power facility. The partial discharge signal detector 120 may include a filter module 121, a rise time calculation module 122 and a signal classification module 123 as shown in FIG. Here, each of the components included in the partial discharge signal detector 120 is divided into functional components to facilitate understanding of the present invention, and actually, it may be implemented as one processing device.

The filter module 121 detects and passes signals in the 0.3 GHz to 3GHz band, and filters out signals in other bands. That is, the filter module 121 performs the function of passing ultrasonic signals in the 0.3 GHz to 3 GHz band for the analysis process described below, and removing the other signals. This is because, as described above, different signals are generated in the 0.3 GHz to 3 GHz band for each of the partial discharge types, and ultrasound signals generated by other causes than the partial discharge through the filter module 121 (for example, External noise, etc.) are cut off, so that the detection accuracy for the partial discharge can be higher.

The rise time calculation module 122 calculates the rise time of the signal with respect to the ultrasound signal filtered through the filter module 121. Here, as shown in FIG. 3, the ultrasonic signal may have a form in which its amplitude repeats rising and falling along the time axis. Here, the rise time is indicated by reference symbol t _r in FIG. 3, and represents the time from the 10% portion to the 90% portion of the signal amplitude at the rising portion of the signal. This rise time is used to divide the ultrasonic signal into a noise signal and a partial discharge signal as described below.

The signal classification module 123 functions to distinguish the ultrasonic signal from the noise signal and the partial discharge signal by comparing the rise time of the ultrasonic signal calculated through the rise time calculation module 122 with the partial discharge judgment time. Specifically, when the rise time of the ultrasonic signal is greater than or equal to the partial discharge determination time, the signal classification module 123 divides the signal portion into noise signals. If the rise time of the ultrasonic signal is less than the partial discharge determination time, It functions to distinguish by signal. When the ultrasonic signal is divided, the signal classifying module 123 removes the noise signal from the ultrasonic signal and transmits the partial discharge signal to the attenuation ratio analyzer 130. Here, the partial discharge determination time may be set to 1 ns, for example, and may be changed to various values depending on the installation environment of the electric power facility.

Also, when the partial discharge signal is detected through the above-described division process, the signal classifying module 123 can determine that a partial discharge has occurred in the electric power facility, and inform the administrator or the user of the partial discharge.

When the partial discharge signal is detected through the partial discharge signal detector 120, the damping ratio analyzer 130 calculates the first peak voltage and the second peak voltage in the partial discharge signal, and outputs the first peak voltage and the second peak And calculates the inter-voltage damping ratio. 4, the damping ratio analysis unit 130 may include a first peak voltage calculation module 131, a second peak voltage calculation module 132, and a damping ratio calculation module 133 have. As described above, each of the components included in the damping ratio analysis unit 130 is divided into functional components to facilitate understanding of the present invention, and actually, it may be implemented as one processing device.

The first peak voltage calculation module 131 and the second peak voltage calculation module 132 function to calculate the first peak voltage and the second peak voltage, respectively, in the partial discharge signal. As described above, the partial discharge signal has its amplitude rising and falling patterns along the time axis as shown in FIG. The first peak voltage calculation module 131 and the second peak voltage calculation module 132 calculate the first peak voltage and the second peak voltage in the order of the amplitude of the partial discharge signal, respectively. Here, the method of calculating the first peak voltage and the second peak voltage through the first peak voltage calculation module 131 and the second peak voltage calculation module 132 can be expressed as shown in the following equations (1) and have.

Further, in the equation (1) and two V _peak1 denotes a first peak voltage, V _peak2 represents a second peak voltage, Q represents the degree is sharp, may be expressed as Equation (3) below, Q is.

The damping ratio calculation module 133 calculates the damping ratio between the first peak voltage and the second peak voltage using the first peak voltage and the second peak voltage detected through Equations 1 and 2 above. Here, the attenuation ratio between the first peak voltage and the second peak voltage can be used for calculating the resonance frequency described below, and the resonance frequency can be used to determine the type of the partial discharge according to the magnitude thereof. The damping ratio between the first peak voltage and the second peak voltage through the damping ratio calculation module 133 can be calculated by Equation (4) and Equation (5) below.

Equation (4) illustrates a method for calculating an attenuation rate (α) between the first peak voltage (V _peak1) and a second peak voltage (V _peak2) through a damping ratio calculation module 133. The In Equation 4 V _peak1 denotes a first peak voltage, V _peak2 the second represents the peak voltage, A is based on the crossing point zero of the signal, as shown in Figure 5, first peak voltage (V _peak1) and _Represents the absolute magnitude comparison value of the second peak voltage (V _peak2 ). In addition, A can be applied to the graph for calculation of the decay rate by utilizing the ζ value of the equation (5) as an element applied to the equation (3) to calculate a more accurate decay rate value.

The damping ratio calculation module 133 calculates the damping ratio between the first peak voltage and the second peak voltage as shown in the following equation (5) using the attenuation ratio [alpha] , Damping ratio,?) Can be calculated.

In Equation (5),? Represents the damping ratio between the first peak voltage and the second peak voltage.

Here, in the case of the partial discharge signal, the damping ratio? Between the first peak voltage and the second peak voltage can be derived according to the type thereof. Accordingly, by analyzing the region using the first peak voltage and the second peak voltage damping ratio? Derived through Equation (5), it is possible to determine the type of the partial discharge accurately. However, in order to more accurately determine the type, it is preferable to derive the resonance frequency through the resonance frequency calculation unit 140 and determine the partial discharge type using the resonance frequency.

The resonance frequency calculator 140 calculates the resonance frequency based on the damping ratio between the first peak voltage and the second peak voltage calculated through the damping ratio analyzer 130. [ Also, when calculating the resonance frequency, the resonance frequency calculation unit 140 can minimize the error that may occur in the partial discharge detection by considering the time difference between the two peak voltages. Here, the resonance frequency calculator 140 can calculate the resonance frequency using Equation (6) below.

In Equation (6), t _d represents the time between the first peak and the second peak in the partial discharge signal, and? Represents a damping ratio between the first peak voltage and the second peak voltage. Here, the time (t _d ) between the first peak and the second peak represents the time between two peak voltages having the highest amplitude in the partial discharge signal, as shown in Fig.

The partial discharge type determining unit 150 functions to determine the type of the partial discharge using the resonance frequency calculated through the resonance frequency calculating unit 140. Specifically, the partial discharge type determining unit 150 can detect the type of the partial discharge according to the magnitude of the resonance frequency calculated through the resonance frequency calculating unit 140. [ For example, in the case of a substation such as a GIS, corona defects, insulator defects, particle defects, and floating defects may exist. The sizes of the resonance frequencies are different depending on the types of defects.

Accordingly, the partial discharge type determining unit 150 can classify the partial discharge type based on the magnitude of the resonance frequency. For example, the partial discharge type determining unit 150 can classify the partial discharge type determining unit 150 as a corona defect when the magnitude of the resonance frequency is about 0.5 GHz, and can classify it as the insulator defect when the magnitude of the resonance frequency is about 1 GHz. Here, the magnitude of the frequency used for the defect determination is merely an example, and the magnitude of the resonance frequency may vary depending on the type of the electric power facility or the installation environment. Therefore, the resonance frequency is not limited to a specific value here.

The partial discharge type determining unit 150 may further determine whether the partial discharge signal is generated by an external noise other than a defect according to the magnitude of the resonance frequency. Accordingly, the partial discharge diagnostic apparatus 100 according to an embodiment of the present invention can more accurately determine whether a defect has occurred, and can diagnose the cause of the partial discharge separately when the partial discharge is generated.

As described above, according to the partial discharge diagnostic apparatus 100 according to one embodiment of the present invention, as an analysis technique using noise elimination, time difference error, and frequency analysis, it is possible to eliminate or minimize the occurrence of diagnostic errors generated in the conventional partial discharge technique There is an advantage that can be made.

In addition, the partial discharge diagnostic apparatus 100 according to an embodiment of the present invention can accurately diagnose whether or not a partial discharge has occurred, and thus can be applied to various fields. For example, in the case of a method of detecting the location of occurrence of partial discharge when partial discharge is generated, it is difficult to accurately calculate the position due to the fact that the detection accuracy of partial discharge is low in the related art, There is a problem that the manager informs the manager that a partial discharge has occurred at the position. On the other hand, when the partial discharge diagnostic apparatus 100 of the present invention is used, it is possible to accurately diagnose whether a partial discharge has occurred, and the signal is a signal in which noises are removed and a time difference error is considered. .

7 is a flowchart illustrating a partial discharge diagnosis method according to an embodiment of the present invention. As described above, in the partial discharge diagnosis method according to an embodiment of the present invention, the noise signal is removed by using the rising time of the signal and the time difference of the frequency with respect to the radio signal measured through the UHF sensor, i.e., the ultrasonic signal, The discharge signal is extracted, and the type of discharge is determined based on the extracted partial discharge signal as well as the partial discharge. Referring now to FIG. 7, a description is given of a partial discharge diagnosis method according to an embodiment of the present invention. In the following, the duplication of the above-mentioned parts is omitted and the description is made.

Step S110 is a step of receiving the ultrasonic signal of the electric power facility by the signal receiving unit. As described above, when the partial discharge exists, the ultrasound signals of the power facility received through step S110 are analyzed in a frequency manner, and the signals for the partial discharge are divided into different bands (for example, 0.3 to 3 GHz) Lt; / RTI &gt; Accordingly, the ultrasound signal is first received through step S110, and the partial discharge diagnosis can be performed through the analysis method described below.

In step S120, the partial discharge signal detection unit separates the noise signal and the partial discharge signal by analyzing the ultrasonic signal. Specifically, in step S120, a time (i.e., a rise time) for a signal from the rising portion of the ultrasonic signal, that is, the signal from the 10% portion to the 90% portion of the signal amplitude is calculated and the rise time of the ultrasonic signal and the partial discharge judgment time Thereby discriminating the noise signal from the partial discharge signal. If the rise time of the ultrasound signal is less than the partial discharge determination time, the signal may be determined as the partial discharge signal. have.

Also, when the partial discharge is generated as described above, the partial discharge signal is present in the range of 0.3 GHz to 3 GHz. Accordingly, the step S120 may include extracting an ultrasonic signal in the 0.3 GHz to 3 GHz band through filtering. Accordingly, the process of analyzing the ultrasound signal through step S120 may be performed on the ultrasound signal within the range of 0.3 GHz to 3 GHz.

The step S130 is a step of determining whether the partial discharge signal is detected by the partial discharge signal detecting unit through step S120. As a result of the determination in step S130, if it is determined that the partial discharge signal is detected, the control is transferred to step S140 to determine that the partial discharge has occurred and notify the administrator or the user of the partial discharge. Otherwise, control passes to step S110 to re-execute the above-described steps.

In step S150, the first peak voltage and the second peak voltage are calculated in the partial discharge signal when the partial discharge signal is detected by the damping ratio analysis unit. In step S160, the first peak voltage and the second peak voltage are calculated by the damping ratio analysis unit. And calculating the second peak voltage damping ratio. Specifically, in operation S150 and S160, the partial discharge signal is divided by the operation S120, and the first peak voltage and the second peak voltage are calculated based on the received partial discharge signal. The calculated first peak voltage and the first peak voltage And calculating the second peak voltage damping ratio. Here, the method of calculating the first peak voltage and the second peak voltage has been described above with reference to equations (1) to (3), and a method of calculating the damping ratio of the first peak voltage and the second peak voltage is expressed by Equations 4 and 5 And therefore, redundant description will be omitted.

In operation S170, the resonance frequency is calculated based on the damping ratio between the first peak voltage and the second peak voltage calculated in operation S160. Here, in step S170, the time between the first peak and the second peak in the partial discharge signal, the first peak voltage calculated in step S160, and the second peak voltage in the partial discharge signal are controlled so that a time error due to a time difference between two peak times does not occur. Can be achieved by considering the damping ratio between peak voltages. Here, the method of calculating the resonance frequency through step S170 has been described in detail with reference to Equation (6) and Equation (7) above, and a further explanation thereof will be omitted.

In operation S180, the partial discharge type is determined based on the magnitude of the resonance frequency calculated in operation S170. That is, in step S180, it is possible to determine the type of partial discharge by at least one of a corona defect, an insulator defect, a particle defect, a floating defect, and an external noise according to the magnitude of the resonance frequency calculated in step S170.

As described above, an optimal embodiment has been disclosed in the drawings and specification. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: partial discharge diagnosis apparatus 110: signal receiving section
120 partial discharge signal detector 130:
140: resonance frequency calculation unit 150: partial discharge type determination unit

Claims (16)

A signal receiving unit for receiving an ultrasonic signal of a power facility; And
And a partial discharge signal detector for discriminating a noise signal and a partial discharge signal by analyzing the ultrasonic signal and determining that a partial discharge is generated in the power equipment when a partial discharge signal is detected,
Wherein the partial discharge signal detector calculates a rise time of the ultrasonic signal and divides a signal whose rising time of the ultrasonic signal is less than a partial discharge judgment time into a partial discharge signal. The method according to claim 1,
Wherein the partial discharge signal detector divides a signal whose rising time is equal to or longer than a partial discharge judgment time into a noise signal. The method according to claim 1,
And a damping ratio analyzer for calculating a first peak voltage and a second peak voltage in the partial discharge signal and calculating a damping ratio between the first peak voltage and the second peak voltage when the partial discharge signal is detected Wherein the partial discharge diagnosis apparatus comprises: The method of claim 3,
Further comprising a resonance frequency calculator for calculating a resonance frequency based on a time between a first peak and a second peak in the partial discharge signal and a damping ratio between the first peak voltage and the second peak voltage, Diagnostic device. 5. The method of claim 4,
The resonance frequency calculation unit
(Equation)

Wherein t _d is a time between a first peak and a second peak in the partial discharge signal and ζ is a time between the first peak voltage and the second peak, Voltage damping ratio). 5. The method of claim 4,
And a partial discharge type determination unit for determining the type of the partial discharge based on the magnitude of the resonance frequency. The method according to claim 6,
The partial discharge type determination unit
Wherein the type of partial discharge is determined by at least one of corona defects, insulator defects, particle defects, floating defects, and external noise depending on the magnitude of the resonance frequency. The method according to claim 1,
Wherein the partial discharge signal detecting unit includes a filter module for detecting a signal in the 0.3 GHz to 3 GHz band,
Wherein the partial discharge signal detecting unit distinguishes between the noise signal and the partial discharge signal by analyzing an ultrasonic signal in a band of 0.3 GHz to 3 GHz. Receiving an ultrasonic signal of a power facility by a signal receiving unit;
Separating the noise signal and the partial discharge signal by analyzing the ultrasonic signal by the partial discharge signal detection unit; And
Determining that a partial discharge has occurred in the power plant when the partial discharge signal is detected by the partial discharge signal detector,
Wherein the step of distinguishing the noise signal and the partial discharge signal comprises:
Calculating a rise time of the ultrasonic signal; And
And dividing a signal whose rising time of the ultrasonic signal is less than a partial discharge judgment time into partial discharge signals. 10. The method of claim 9,
Wherein the step of distinguishing the noise signal and the partial discharge signal comprises:
Further comprising the step of: dividing a signal whose rising time is equal to or longer than a partial discharge judgment time into a noise signal. 10. The method of claim 9,
Calculating, by the damping ratio analysis unit, a first peak voltage and a second peak voltage in the partial discharge signal when the partial discharge signal is detected; And
And calculating a damping ratio between the first peak voltage and the second peak voltage by the damping ratio analysis unit. 12. The method of claim 11,
The step of calculating the resonance frequency by the resonance frequency calculation unit based on the time between the first peak and the second peak in the partial discharge signal and the damping ratio between the first peak voltage and the second peak voltage The method comprising the steps of: 13. The method of claim 12,
The step of calculating the resonance frequency based on the attenuation ratio between the first peak voltage and the second peak voltage
(Equation)

Wherein t _d is a time between a first peak and a second peak in the partial discharge signal and ζ is a damping ratio between the first peak voltage and the second peak voltage, . 13. The method of claim 12,
Further comprising the step of determining, by the partial discharge type determining unit, the type of the partial discharge based on the magnitude of the resonance frequency. 15. The method of claim 14,
Wherein determining the type of partial discharge based on the magnitude of the resonant frequency comprises:
Wherein the type of partial discharge is determined by at least one of corona defects, insulator defects, particle defects, floating defects, and external noise depending on the magnitude of the resonance frequency. 10. The method of claim 9,
Further comprising a step of detecting a signal in the 0.3 GHz to 3 GHz band by the partial discharge signal detecting unit,
Wherein the step of distinguishing the noise signal from the partial discharge signal by analyzing the ultrasonic signal is performed by analyzing ultrasonic signals in the range of 0.3 GHz to 3 GHz.

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