KR102247156B1 - Arrester condition monitoring device with leakage current monitoring and surge counting - Google Patents

Abstract

Disclosed is a lightning arrester status monitoring device having a leakage current monitoring and surge counting function, which is a technical idea of the present invention. An object of the present invention is to provide a lightning arrester status monitoring device having the leakage current monitoring and surge counting functions, which accurately determines whether a leakage current is present, and predicts a lifespan by counting a surge in the case of a lightning strike exceeding a critical current. The present invention can have an effect of accurately detecting leakage current by analyzing 3 harmonic components, and replacing a worn-out arrester when surge counting exceeding a threshold occurs through surge counting during lightning strikes.

Description

Arrester condition monitoring device with leakage current monitoring and surge counting function {ARRESTER CONDITION MONITORING DEVICE WITH LEAKAGE CURRENT MONITORING AND SURGE COUNTING}

The present invention relates to a lightning arrester condition monitoring device having a leakage current monitoring and surge counting function, and more particularly, a leakage current monitoring and surge counting function that detects a change in leakage current and predicts life through surge counting in the event of a lightning strike. It relates to a monitoring device.

The lightning arrester insulates the line when it is in a normal state and transmits a lightning strike to the ground in case of a lightning strike. The condition detector estimates the life of the arrester by measuring the leakage current of the arrester when it is in a normal state, and estimates the life of the arrester by the number of surge occurrences through surge counting in the event of a lightning strike. As the conventional state detector measures the leakage current through the leakage current detector, the signal of the leakage current is weak, so it is not possible to measure the correct leakage current change, and there is a problem in that the surge counting also does not operate properly.

Registration No. 10-0473084, Arrester's Deterioration Diagnosis Measurement Device by Leakage Current Wave Height Analysis Registration number 10-0993519, surge arrester

An object of the present invention is to provide an apparatus for monitoring a state of a lightning arrester having a function of monitoring a leakage current and a surge counting function that accurately determines whether a leakage current is present and predicts a life by surge counting when a lightning strike exceeds a critical current.

In addition, an object of the present invention is to provide an apparatus for monitoring a condition of a lightning arrester having a function of monitoring a leakage current and a surge counting function that increases a diagnosis time.

An apparatus for monitoring a state of a lightning arrester having a function of monitoring a leakage current and a surge counting according to an exemplary embodiment of the present invention includes: a leakage current detector for sensing a current in each phase of a discharge column inside the arrester; A first amplifier amplifying the current signal of the leakage current detector; An optical converter for optically converting the amplified current signal; A signal converter for converting the light-converted current signal into an electric signal; A second amplifier amplifying the converted electrical signal; A third harmonic filter for filtering and outputting a third harmonic from among the electrical signals amplified by the second amplifier; And a state monitoring unit that detects a change in leakage current by analyzing the components of the three harmonics, and counts a surge when a lightning strike exceeds a threshold current.

In addition, the state monitoring unit performs a relative monitoring function of the phase by alternately measuring a current level for one of the phases from the leakage current detector in the sleep mode according to the sleep mode or the normal mode.

In addition, in the sleep mode, the state monitoring unit switches to the normal mode when the third harmonic exceeds the first threshold value when the first cycle arrives to activate the monitoring function for all phases, and when the second cycle arrives. When the third harmonic exceeds the second threshold, an approximate curve function is generated to predict the life of the arrester.

The present invention can have the effect of accurately detecting whether there is a leakage current by analyzing a third harmonic component, and replacing a lightning arrester that has reached the end of its life when a surge counting exceeding a threshold value occurs through surge counting during a lightning strike.

In addition, the diagnosis time may be increased by minimizing the amount of power for detecting the leakage current, and the reliability of the leakage current detection of the arrester may be increased due to the longer diagnosis time.

1 is an exemplary view showing an installation state diagram of a lightning arrester.
2 is an exemplary diagram for outputting 3 harmonics from a leakage current detector.
3 is an exemplary diagram showing a relationship between a leakage current and a third harmonic.
4 is a block diagram showing the configuration of a state detection unit.
5 is an exemplary view showing leakage current of a lightning protection element for each phase in a lightning arrester.
6 is a flowchart illustrating an operation of a simple diagnosis process of a simple diagnosis unit.
7 is a flowchart illustrating a predictive diagnosis process of a predictive diagnosis unit.

In the present invention, various modifications may be made and various embodiments may be provided, and specific embodiments will be illustrated in the drawings and will be described in detail in the detailed description. However, this is not intended to limit the present invention to a specific embodiment, it should be understood to include all changes, equivalents, or substitutes included in the spirit and scope of the present invention.

In describing each drawing, similar reference numerals have been used for similar elements. In describing the present invention, when it is determined that a detailed description of a related known technology may obscure the subject matter of the present invention, a detailed description thereof will be omitted.

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

For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

The term and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof does not preclude in advance.

Unless otherwise defined, all terms used herein including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in the present application. Does not.

Hereinafter, an apparatus for monitoring a state of a arrester having a leakage current monitoring and a surge counting function according to an exemplary embodiment of the present invention will be described in detail with reference to the drawings. Hereinafter, descriptions of conventionally well-known items will be omitted or simplified in order to clarify the gist of the present invention.

1 is an exemplary view showing an installation state diagram of a lightning arrester.

Lightning elements 21, 22, and 23 are connected to the busbars 11, 12, and 13, which are lines. The lightning arrester may have lightning protection elements 21, 22, and 23. The leakage current detectors 31, 32, 33 detect leakage currents at the output terminals between the lightning protection elements 21, 22, and 23 and the ground. The state monitoring unit 40 analyzes the detected leakage current to determine the presence or absence of a leakage current, and performs surge counting in case of a lightning strike.

2 is an exemplary diagram for outputting 3 harmonics from a leakage current detector.

The leakage current detector 31 detects the current of each phase of the discharge column inside the arrester, the first amplifier 31a amplifies the current signal of the leakage current detector, and the optical converter 31b photoconverts the amplified current signal. , The signal converter 31c converts the light-converted current signal into an electric signal, the second amplifier 31d amplifies the converted electrical signal, and the third harmonic filter 31e is amplified by the second amplifier 31d. Among the generated electrical signals, the third harmonic is filtered and output.

3 is an exemplary diagram showing a relationship between a leakage current and a third harmonic.

There are two methods of measuring the leakage current: the total leakage current and the resistance leakage current. The method of measuring the total leakage current is simple, but the size of the capacitive leakage current is large, so the change in leakage current at the beginning of deterioration. Since is small, it is difficult to determine the initial deterioration state, so it is possible to make a more stable diagnosis by using the method of detecting the leakage current of the resistor through the third harmonic analysis.

4 is a block diagram showing the configuration of a state detection unit.

The leakage current detection unit 41 detects the leakage current level based on the third harmonic component, and the simple diagnosis unit 42 diagnoses the leakage current level alternately between one of the phases in the sleep mode, and predictive diagnosis. The unit 43 predicts the leakage current by generating an approximate curve function according to the leakage current change, the data management unit 44 manages the leakage current data, manages the number of surge counted surges, and the storage unit 45 The leakage current data and the number of surges are stored, the alarm unit 46 alarms the leakage current exceeded and the surge number exceeded, and the communication unit 47 transmits the leakage current exceeding and the surge number exceeding to an external server.

5 is an exemplary view showing the leakage current of the lightning protection element for each phase in the lightning arrester.

In the leakage current graph of the lightning protection device for each phase, it is predicted that the leakage current of the R phase will exceed the second threshold and will also exceed the first threshold, and the S phase and T phase are in a normal state that does not exceed the second threshold. Is judged. In the case of the S-phase and T-phase, the second threshold has not been exceeded, but it is predicted that the second threshold will be exceeded after a certain period of time when the approximate curve function is applied. After the leakage current of the R phase exceeds the second threshold value, a state may occur in the S phase and the T phase to exceed the second threshold value.

6 is a flowchart illustrating an operation of a simple diagnosis process of a simple diagnosis unit.

The simplified diagnosis unit 42 determines whether the first threshold value is exceeded for one of the R, S, and T phases when the first cycle arrives in the sleep mode, and when the first period is exceeded, switches to the normal mode. In the normal mode, the simple diagnosis unit 42 determines whether the first threshold value is exceeded for all of the R, S, and T phases. Since the simple diagnosis unit 42 determines whether the first threshold value is exceeded for one of the phases in the sleep mode, the amount of power required for the simple diagnosis is minimized, thereby prolonging the diagnosis time. When the condition monitoring unit 40 is located inside the arrester and the simple diagnosis is performed in the arrester, the smaller the amount of power required for the simple diagnosis, the less battery consumption and thus a longer operation time. The simple diagnosis unit 42 adjusts the amount of power required for the simple diagnosis by adjusting the value of the first cycle. When the value of the first cycle increases, the amount of diagnostic power decreases, and when the value of the first cycle decreases, the amount of diagnostic power increases.

7 is a flowchart illustrating a predictive diagnosis process of a predictive diagnosis unit.

The predictability diagnosis unit 43 stores the leakage current value, determines whether the second threshold value is exceeded when the second period arrives, and generates an approximate curve function when the second period is exceeded. The approximate curve function predicts the leakage current value after a certain time from the previous leakage current value. The predictability diagnosis unit 43 estimates the life by determining whether the leakage current value exceeds the second threshold value using an approximate curve function. The predictability diagnosis unit 43 predicts that the life of the arrester is over when the leakage current value exceeds the second threshold value.

The state monitoring unit 40 alternately measures the current level for one of the phases from the leakage current detectors 31, 32, 33 in the sleep mode according to the sleep mode or the normal mode to provide a relative monitoring function for the phases. Carry out.

The state monitoring unit 40 activates the monitoring function for all phases by switching to the normal mode when the third harmonic exceeds the first threshold value when the first cycle arrives in the sleep mode, and when the second cycle arrives, the If the third harmonic exceeds the second threshold, an approximate curve function is generated to predict the lightning arrester life.

The present invention is not limited to the specific preferred embodiments described above, and any person having ordinary knowledge in the technical field to which the present invention pertains without departing from the gist of the present invention claimed in the claims can implement various modifications. Of course, such changes are intended to be within the scope of the description of the claims.

11, 12, 13: Mothership
21, 22, 23: lightning protection element
31, 32, 33: leakage current detector
40: state monitoring unit
41: leakage current detection unit
42: simple diagnosis unit
43: predictive diagnosis unit
44: data management department
45: storage
46: alarm unit
47: communication department
50: surge counter

Claims (3)

A leakage current detector for sensing a current in each phase of the discharge column inside the arrester;
A first amplifier amplifying the current signal of the leakage current detector;
An optical converter for optically converting the amplified current signal;
A signal converter for converting the light-converted current signal into an electric signal;
A second amplifier amplifying the converted electrical signal;
A third harmonic filter for filtering and outputting a third harmonic from among the electrical signals amplified by the second amplifier; And
Including; a state monitoring unit that detects a change in leakage current by analyzing the components of the three harmonics, and counts a surge when a lightning strike exceeds a threshold current,
The state monitoring unit performs a relative monitoring function for the phase by measuring a current level alternately for each of the three harmonics output from the leakage current detector in the sleep mode,
A simple diagnosis unit for activating a monitoring function for all phases by switching to a normal mode when the third harmonic exceeds a first threshold value when the first cycle arrives in the sleep mode;
When the second cycle arrives, when the third harmonic exceeds the second threshold, a predictability diagnosis unit that generates an approximate curve function to predict the life of the arrester; further comprises a leakage current monitoring and surge counting function. Branch is a arrester condition monitoring device. delete delete

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