KR101882715B1 - Gis system of remote diagnosis and gas density having partial discharge diagnosis function - Google Patents

Abstract

The present invention relates to a gas insulated switchgear (GIS) remote diagnosis system having a partial discharge and a gas density diagnosis device, capable of detecting partial discharge and gas density occurring inside a gas-insulated power device, remotely confirming a detection result, and diagnosing whether a breaker is opened or injected based on the diagnosis result. According to the present invention, the 29 KV GIS remote diagnosis system having a partial discharge and a gas detection diagnosis device comprises: a partial discharge detection device for detecting partial discharge inside a GIS; a gas density detection device for detecting the density of insulated gas filled in the GIS; a breaker operating characteristic detection device for detecting operating characteristics of a breaker installed in the GIS; a diagnosis device for diagnosing partial discharge, gas density, and breaker operating characteristics based on data values outputted from the partial discharge detection device, the gas density detection device, and the breaker operating characteristic detection device; and a display device for displaying information outputted from the diagnosis device. The gas density detection device is configured to detect the density of the insulated gas by a difference value between a frequency in a vacuum state and a frequency in a state of being in contact with the insulated gas.

Description

TECHNICAL FIELD [0001] The present invention relates to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus,

The present invention relates to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus, and more particularly, to a 29KV GIS remote diagnosis system for detecting partial discharge and gas density for an insulated gas generated inside a gas- And a 29 KV GIS (Gas Insulated Switchgear) remote diagnosis system equipped with a partial discharge and gas density diagnosis device capable of checking the detection result remotely and diagnosing whether the breaker is open or closed based on the detection result.

The term "partial discharge" refers to any part of the power equipment system, such as power receiving equipment installed in various industrial and power system substations, high voltage switchgear, high voltage cable, transformer, GIS (Gas Insulated Switchgear), switchgear, Generally referred to is a corona discharge occurring near the tip of the electrode, a surface discharge occurring along the surface of the insulator, and a void discharge occurring in the pores in the insulator.

It is very important to monitor the abnormality of the power equipment and to monitor the degree of deterioration of the insulator and to predict the repair time, and it is possible to predict and manage such by measuring and monitoring the partial discharge. For this purpose, a partial discharge of various power facilities such as high voltage cable, transformer, gas insulated switchgear (GIS), switchgear, power supply facility, high voltage panel, low voltage panel, motor control panel, Measuring devices are being used.

As a technique for remotely controlling a GIS, a digitized GIS field control system is disclosed in Patent Registration No. 10-0895218.

The technique includes a housing having a constant internal volume; A CPU provided in the housing for receiving and digitizing the state information of the GIS and the transformer to generate a digital signal for the GIS and the transformer state, and controlling the GIS and the transformer; A communication protocol converter connected to the CPU for converting a digital signal of the GIS and transformer state into a communication protocol; A display unit connected to the CPU and providing a screen for on-site control of the GIS; An input / output control cable for connecting the CPU and the detailed equipment of the GIS for controlling the GIS; A control unit connected to the CPU and the GIS to control a trip control for disconnecting the current flow when an abnormality occurs in the current flowing between the GIS and the transformer and a control unit for connecting the communication protocol conversion unit and the control panel of the switchgear room And an optical cable for transmitting the communication protocol generated by the communication protocol conversion unit to the control panel and receiving the communication protocol of the control panel.

However, the above-described technique does not describe a technology structure capable of detecting a partial discharge that can be generated inside a GIS and a structure capable of detecting the density of insulated gas filled in the GIS. Based on the detection result, So that it is impossible to diagnose whether the breaker is open or closed.

KR 10-0895218 B1 (2009. 04. 21.)

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the prior art, and it is an object of the present invention to provide a partial discharge capable of detecting a partial discharge in a GIS and selectively opening or closing a breaker according to a detection result And a 29 KV GIS remote diagnosis system equipped with a gas density diagnostic apparatus.

Another problem to be solved by the present invention is to provide a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus which can detect insulation gas density in a GIS and ensure safety against insulation .

In order to solve the above problems, a 29 KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention includes a partial discharge detection apparatus for detecting a partial discharge inside a GIS; A gas density detecting device for detecting the density of the insulated gas filled in the GIS; A breaker operation characteristic detecting device for detecting an operation characteristic of the breaker installed in the GIS; A diagnostic device for diagnosing partial discharge, gas density, and circuit breaker operation characteristics based on data values output from the partial discharge detection device, the gas density detection device, and the circuit breaker operation characteristic detection device; And a display device for displaying information output from the diagnostic device, wherein the gas density detecting device measures a density of the insulating gas by a difference between a frequency in a vacuum state and a frequency in a state of being in contact with an insulating gas Is detected.

Here, the gas density detecting apparatus may include a housing having a cylindrical shape with a lower opening; A threaded portion formed on the housing and screwed on the outer surface of the housing of the GIS; A securing portion for securing a state in which the housing is screwed to the housing by inserting the screw portion into the housing by screwing in a state where the screw portion is screwed to the housing; A first oscillator installed inside the housing and outputting a frequency by a voltage applied in a vacuum state; A second oscillator installed inside the housing and outputting a frequency by applying a voltage in a state of being exposed to the insulating gas; And a comparator outputting a difference value between the first oscillator and the second oscillator, the current value being a difference value between the first oscillator and the second oscillator.

Also, the partial discharge detecting device may include a sensor flange coupled to an outer surface of the GIS enclosure; A sensor support coupled to an inner surface of the sensor flange; A sensor antenna attached to the sensor support; A sensor cover coupled to the sensor flange at the inside of the GIS enclosure and sealing the outside of the sensor support and the sensor antenna; And a connector installed on an outer surface of the sensor flange and electrically connected to the sensor antenna to output a signal.

At this time, the device for detecting a breaker operation characteristic may be configured such that a mechanical operation time for a time interval from the time when an electrical signal is inputted to the trip coil to the completion of the operation of the trip coil according to a trip signal of the breaker, And the current is detected.

In addition, the circuit breaker operation characteristic detecting device includes: a current signal input unit for inputting an operation current signal of the circuit breaker and a load current signal of the power facility; A contact state signal input unit for inputting a contact state signal of the blocking coil and the closing coil of the circuit breaker; And a processor for analyzing the operation current signal and the load current signal to calculate data representing an operating characteristic of the circuit breaker.

According to the present invention, since the partial discharge inside the GIS can be detected and the breaker can be selectively opened or closed according to the detection result, it is possible to prevent burning of the power device and protect the load side.

In addition, there is an advantage that a safety accident against an electric shock or the like can be prevented by detecting and diagnosing the density of the heat transfer gas.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram of a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus according to the present invention; FIG.
2 is a block diagram of a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus according to the present invention;
3 is a view illustrating an installation state of a partial discharge detection device applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention.
FIG. 4 is an exploded perspective view of the partial discharge detecting device of FIG. 3; FIG.
FIG. 5 is an installation cross-sectional view of the partial discharge detecting device of FIG. 3;
6 is a plan view of a sensor antenna according to an embodiment of the present invention applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus according to the present invention.
7 is an external view of a gas density detecting apparatus applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention.
8 is an internal structural view of the gas density detecting device of Fig.
9 is a block diagram of an apparatus for detecting a breaker operation characteristic applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention.
10 shows a partial discharge diagnostic algorithm applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus displayed on a display device.
FIG. 11 is a graph (a) mapped to a time domain interface and a frequency domain interface for a void partial discharge, a graph (b) mapped to a time domain interface and a frequency domain interface for a creep partial discharge, Graphs mapped to interfaces and frequency domain interfaces (c).

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention can detect the partial discharge and the gas density with respect to the insulated gas generated in the inside of a power-driven electric power apparatus, remotely confirm the detection result, and diagnose whether the breaker is open or closed based on the detection result To a 29 KV GIS (Gas Insulated Switchgear) remote diagnosis system equipped with a partial discharge and gas density diagnostic device.

FIG. 1 is a schematic block diagram of a 29 KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention. FIG. 2 is a schematic diagram of a 29 KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention. GIS remote diagnosis system.

1 and 2, a 29 KV GIS remote diagnosis system including a partial discharge and gas density diagnosis apparatus according to the present invention includes a GIS 10, a partial discharge detection device 100, a gas density detection device 200, a breaker operation characteristic detecting device 300, a diagnosis control device 400, and a display device 500.

GIS (10, Gas Insulated Switchgear) is used to open and close circuit breakers, disconnectors, etc., transformers, lightning arresters, main circuit buses, etc. in a metal tank, and the live parts are supported by solid insulators tank as inside insulation and closing the plant one extinguishing capacity is filled, sealed by an insulating medium superior SF ₆ gas, the insulating performance is made compact, and the wide range and excellent etc. stability, environmental harmony by sealing the superior SF ₆ gas .

The GIS 10 is a highly reliable power device having a low voltage and low failure factor since it is a sealed structure in which a high voltage part is enclosed in a metal container and thus is not influenced by the atmosphere.

However, since the GIS can not see the inside of the GIS, it is difficult to detect an abnormality occurring inside. If a failure such as insulation breakdown occurs, the effect of the accident is large, and the recovery takes a long time.

Most of the GIS accidents are caused by the presence of metallic particles, incomplete contact of the conductors, defects in the spacers, insufficient quality control during the assembly process, and foreign matter due to mechanical wear during GIS operation. Partial discharge, especially in GIS, is likely to reach full destruction, and it should be detected and followed up soon.

Partial discharges in the GIS emit up / down sudden discharge pulses and emit ultra high frequency (UHF) in the range of 300 MHz to 1.5 GHz. Since the radiated UHF microwave propagates as a microwave through the coaxial GIS channel, a UHF sensor must be installed inside the GIS to detect it. In this case, since the detection value detected from the UHF sensor installed in the GIS must be transmitted to the outside of the GIS, a partial discharge detection device having a structure capable of transmitting the detection value of the UHF sensor to the outside while maintaining the GIS closed state is required.

FIG. 3 is an installation view of a partial discharge detecting apparatus applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention, FIG. 4 is an exploded perspective view of the partial discharge detection apparatus, And Fig.

3 to 5, the partial discharge detecting apparatus 100 includes a sensor flange 110, a sensor support 120, a sensor antenna 130, a sensor cover 140, and a connector 150 .

The sensor flange 110 is coupled to the outer surface of the enclosure (or enclosure, B) of the GIS and is coupled to the enclosure B by a flange fixing screw 111 passing through the formed hole (not shown) .

At this time, a predetermined hole is formed in the enclosure (B) where the sensor flange (110) is installed, and the outer diameter of the sensor flange is formed to be larger than the diameter of the hole formed in the enclosure (B).

The sensor flange 110 is coupled to the enclosure B so that the contact surface between the sensor flange 110 and the enclosure B is sealed to seal the interior and the exterior of the enclosure B. A flange o-ring 113 is installed.

A flange groove 112 is formed in the sensor flange 110 so that the flange o-ring 113 guides the position of the sensor flange 110.

The sensor support 120 is coupled to an inner surface of the sensor flange 110 to support a sensor antenna 130, which will be described later. The sensor support 120 has a central opening and a donut shape.

The center axis of the sensor support 120 and the center axis of the sensor flange 110 may be coaxially mounted and the sensor support 120 may be coupled to the sensor flange 110 by a support coupling screw 121. [ do.

The sensor antenna 130 is attached to the sensor support 120 and detects a frequency generated by the partial discharge.

Partial discharge is a kind of discharge phenomenon, which means insufficient dielectric breakdown that does not intertwine between the electrode and the electrode, which occurs at the pores of the solid insulator, the gas drop of the liquid insulator, the contact interface of the heterogeneous insulator, When such a partial discharge occurs, heat is generated, collision of charged particles, and chemical attack by molecules and ions damage the surrounding solid insulator.

Partial discharges are accompanied by frequency, and the area of generated frequency is ultra high frequency (UHF) in the range of 300MHz ~ 1.5GHz for special high voltage power equipment.

Accordingly, the sensor antenna 130 receives the UHF frequency accompanied by the partial discharge.

FIG. 6 is a plan view of a sensor antenna of a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to an embodiment of the present invention.

The pattern of the antenna is important to detect the microwave in the range of 300 MHz to 1.5 GHz caused by the partial discharge.

Referring to FIG. 6, the sensor antennas 130 are formed as a pair of left and right antennas, and the left and right antennas are configured to form point symmetry.

At this time, the antenna pattern on one side is composed of a fan-shaped base plate 131 and a plurality of side plates 132 extending from the base plate 131 at each side of the base plate 131 and having a predetermined width .

The width of the side plate 132 is smaller as the width of the side plate 132 is closer to the central portion of the side plate 132 and the width of the side plate 132 Are formed to taper in the center direction. The side plates 132 having such a configuration may be provided on each of the left and right sides.

The sensor cover 140 is coupled to the sensor flange 110 inside the enclosure and seals the outside of the sensor support 120 and the sensor antenna 130. The sensor cover 120 includes a sensor support 120, A space for accommodating the antenna 130 is provided.

Here, the sensor cover 140 may be coupled to the sensor flange 110 by a coupling screw. A through hole is formed through the sensor cover 140 in a circumferential direction of the sensor cover 140 so that the sensor cover 140 is coupled to the sensor flange 140 by a cover engagement screw 141. [ (Not shown).

A cover groove 142 is formed between the sensor flange 110 and the sensor cover 140 in the circumferential direction on the contact surface of the sensor cover 140 that is in contact with the sensor flange 110, And a cover O-ring 143 is installed in the cover groove 142. [

The cover O-ring 143 is compressed to prevent the sensor antenna 130 from being exposed to the inner insulation gas (or air) of the enclosure B while being coupled by the engagement of the cover engagement screw 141 do.

The connector 150 is installed on the outer surface of the sensor flange 110 and is electrically connected to the sensor antenna 130 to output a signal.

That is, the connector 150 outputs the frequency detected by the sensor antenna 130 to the outside. The connector 150 is connected to the left and right antennas constituting the sensor antenna 130, (Not shown).

The gas density detecting apparatus 200 performs a function of detecting the density of the insulated gas filled in the GIS 10.

The SF ₆ gas that is filled in the GIS is a non-toxic, odorless, and non-flammable gas with excellent insulation, and the metal tanks other than the bushing are completely grounded to the earth. Therefore, safety of the operator can be secured and the operator may touch the live part There is no.

Here, the dielectric breakdown voltage of the SF ₆ gas is characterized by being proportional to the gas pressure or density. That is, since the breakdown voltage of the SF ₆ gas rises in proportion to the gas pressure, the dielectric strength is determined by the gas pressure.

SF ₆ gas is decomposed by an extremely stable gas at room temperature or by partial discharge (arc). When the SF ₆ gas is decomposed, the SF ₆ gas is recombined and returned to its original state. However, a part of the SF ₆ gas reacts with moisture and is lost due to the recombination process.

As well as decomposition of such a SF ₆ gas leakage of SF ₆ gas filled in the GIS shows a decrease in the insulation performance of the internal

Accordingly, in the present invention, the gas density detecting apparatus 200 is installed to detect the density of the SF ₆ gas filled in the GIS in real time.

FIG. 7 is an external configuration diagram of a gas density detection apparatus applied to a 29 KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention, and FIG. 8 is an internal configuration diagram of the gas density detection apparatus.

7 and 8, a gas density detecting apparatus 200 according to the present invention includes a housing 210, a screw 220, a fixing unit 230, a power applying unit 240, a first oscillator 250, a second oscillator 255, a comparison unit 260, and an output unit 270.

The housing 210 has a cylindrical shape with an opening at the bottom and the threaded portion 220 is formed at the lower portion of the housing 210 and screwed to the housing at the outer surface of the housing of the GIS 10.

In the state where the screw portion 220 is screwed to the housing, the fixing portion 230 is fitted to the housing by screwing to firmly fix the housing 210 in a state where the housing 210 is screwed to the housing.

If necessary, the fixing part 230 may be further provided with a packing ring for sealing the housing.

The power application unit 240 supplies power from the outside to the first and second oscillators 250 and 255. The power source is applied in the range of 10 to 30 V DC.

The first and second oscillators 250 and 255 are provided inside the housing 210 to detect the frequency of the applied voltage and the frequency of the SF ₆ gas. (251) and a negative electrode plate (252) to which a negative voltage is connected.

At this time, crystals may be used for the positive electrode plate and the negative electrode plate.

The first oscillator 250 is installed inside the housing and outputs a current value by a voltage applied in a vacuum state.

The second oscillator 255 is installed inside the housing and outputs a current value by applying a voltage in a state of being exposed to the insulating gas.

A current flows between the positive electrode and the negative electrode through the SF ₆ gas by a power source applied from the power applying unit 240. The amount of the current flowing is proportional to the density of the SF ₆ gas. That is, the higher the density of the SF ₆ gas is, the larger the amount of current flowing is.

The comparator 260 outputs a difference value between the first oscillator 250 and the second oscillator 255 by a power source applied from the power applying unit 240.

Here, the comparator 260 may be a subtractor. At this time, the difference value of the frequency detected by the comparator 260 is output in the range of 0 to 20 mA, and the density is calculated based on the output current value.

The comparator 260 sets the frequency detected by the first oscillator 250 as a reference frequency and the difference value with respect to the variable frequency output from the second oscillator 255 is used as data for calculating the density As a result, as the concentration of insulated gas in the GIS decreases, the frequency of the oscillation output from the second oscillator 255 decreases.

The breaker operation characteristic detecting device 300 performs a function of detecting the operation characteristics of the breaker installed in the GIS.

The circuit breaker may be composed of one selected from an oil breaker (OCB), a gas breaker (GCB), a vacuum breaker (VCB), an air breaker (ABB) and a magnetic breaker (MBB).

This circuit breaker is a power device that protects power devices and prevents safety accidents by quickly breaking fault currents (short circuit, ground fault, etc.).

At this time, the performance of the circuit breaker is evaluated according to the rated breaking time. The rated breaking time of the circuit breaker is the time of the breaking time when the rated breaking current is cut off according to the standard operating obligation and operating condition specified in all rated and prescribed circuit conditions The limit. That is, this means the time from when the circuit breaker receives the trip signal and when the trip circuit is operated by the received closing signal to complete the current interruption.

Here, the trip coil is an important factor for determining the opening and closing of the circuit breaker, and the operating time of the trip coil is a main factor for determining the operating obligation of the circuit breaker.

Accordingly, in the present invention, the operating time of the trip coil can be separately detected at the rated breaking time.

That is, the circuit breaker operation characteristic detecting device 300 detects the mechanical break time for the time interval from the time when the electrical signal is inputted to the trip coil to the completion of the operation of the trip coil according to the trip break signal, So that it can be outputted.

In order to detect the fault current of each phase for operating the trip coil of the circuit breaker, the circuit breaker operation characteristic detecting device 300 is provided with a current transformer (CT) on each phase, Lt; / RTI >

9 is a block diagram of a circuit breaker operation characteristic detecting apparatus applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnosis apparatus according to the present invention.

9, the circuit breaker operation characteristic detecting apparatus 300 includes a current signal input unit 310, a contact state signal input unit 320, and a processing unit 330.

The current signal input unit 310 may include first to fifth current converters.

The first to third current deflectors are installed on the R phase, the S phase, and the T phase to detect the current of each phase to detect the load current.

The fourth current transformer and the fifth current transformer are installed on the breaking coil and the closing coil of the trip coil to measure the operating current of the trip coil TC, respectively, and detect the current for opening and closing the trip coil.

The contact state signal input unit 320 measures the contact state between the breaking contact and the closing contact of the circuit breaker and the operation state of the circuit breaker. To this end, the contact state signal input unit 320 includes a contact state measuring unit, detects the measured contact state signal, and provides the result of the detected signal to the processing unit 330.

The processing unit 330 calculates the rated breaking time and the mechanical operation time of the circuit breaker based on the current value and the contact state signal provided from the current signal input unit 310 and the contact state signal input unit 320, The detected value of the fault current is processed as data readable by the computer and output.

On the other hand, the UHF electromagnetic wave generated by the partial discharge inside the GIS is pure UHF electromagnetic wave, and in the case of pure UHF electromagnetic wave, it can be easily detected whether the partial discharge occurs by detection.

However, various noise is generated in the inside and the outside of the GIS, and the electromagnetic waves due to such noise have a disadvantage that the electromagnetic waves due to the partial discharge or the noise inside and outside are ambiguous.

Noise generated from inside and outside of GIS consists of continuous and periodic noise caused by resonance interference or radio frequency of electric power system, pulse noise generated from equipments such as high voltage corona, power switch, and sideline rectifier Such noise is generated either singly or mixedly with partial discharge, and in particular, some noise is very similar to a partial discharge signal.

Accordingly, in the present invention, it is possible to perform real-time monitoring of partial discharges while effectively suppressing noise interference to secure partial discharge signal detection reliability, and it is possible to perform phase analysis in the time domain and frequency component variation analysis in the frequency domain simultaneously Time-modulated frequency (T-MF) map that can be monitored.

The main characteristic that distinguishes between UHF electromagnetic waves generated by partial discharge and electromagnetic waves due to noise is duration time. That is, the UHF electromagnetic wave generated by the partial discharge has a relatively short impulse and a high frequency pattern than the electromagnetic wave caused by the noise.

If the detected UHF electromagnetic wave is displayed on the T-MF Map, the electromagnetic wave clusters for the UHF electromagnetic wave and the noise are formed differently for the partial discharge.

Accordingly, when the electromagnetic wave cluster for noise is removed, the UHF electromagnetic wave generated by the pure partial discharge can be detected.

The shutdown control apparatus 400 performs a function of diagnosing partial discharge, gas density, and breaker operation characteristics based on data values output from the partial discharge detection device, the gas density detection device, and the breaker operation characteristic detection device.

That is, the shutoff control apparatus 400 determines whether partial discharge in the GIS has occurred based on the partial discharge signal detected by the partial discharge detection apparatus 100, outputs a trip signal to the breaker according to the determination result, A danger signal or a breaker trip signal is output step by step on the basis of the current value detected by the gas density detecting device 200 and the operation characteristic of the circuit breaker is outputted based on the data value detected by the circuit breaker operation characteristic detecting device.

At this time, the shutdown control apparatus 400 may be configured to accumulate (calculate) the partial discharge detection data to determine whether or not the power equipment system is abnormal.

In addition, a partial discharge diagnosis algorithm is applied to the cut-off control apparatus 400 for distinguishing an electromagnetic wave signal of a partial discharge from an electromagnetic wave signal of a noise to remove an electromagnetic wave signal due to noise and diagnose a partial discharge.

The partial discharge diagnosis algorithm converts electromagnetic wave data measured over time into a frequency domain through Fourier transform and maps the converted frequency to a time-modulated frequency (T-MF) map. By using the noise canceling algorithm, the signal for the partial discharge and the signal for the noise are separated and removed, and the pattern of the partial discharge is analyzed to diagnose the cause of the partial discharge.

The partial discharge diagnosis algorithm will be described in detail.

First, the UHF electromagnetic wave signal s (t) by partial discharge is mathematically modeled, and the standard deviation with respect to time using the center of gravity of the modeled UHF electromagnetic wave signal is calculated by the following equation (1).

Here, σ _T is the standard deviation in the time domain, T is the period, t is the weight, t ₀ is the center of gravity, and s (t) is the UHF electromagnetic signal.

Also, the center of gravity t ₀ is expressed by the following equation (2).

Here, t ₀ is the center of gravity, t is the weight, and s (t) is the UHF electromagnetic signal

The standard deviation of the frequency obtained by Fourier-transforming s (t) in the above equation (1) is calculated by the following equation (3).

Here, σ _F is the standard deviation in the frequency domain, f is the frequency, and S (f) is the Fourier transform function of the UHF electromagnetic signal.

According to Equations (1) and (3), the detected UHF electromagnetic wave signal is calculated as information on the time domain and information on the frequency domain.

If the calculated UHF electromagnetic wave is displayed on the T-MF Map, a cluster of electromagnetic waves for the UHF electromagnetic wave and noise for the partial discharge is formed differently. Accordingly, when the electromagnetic wave cluster for noise is removed, the UHF electromagnetic wave generated by the pure partial discharge can be detected.

At this time, the cluster cluster for the partial discharge can be configured to remove the electromagnetic wave signal due to the noise by using the information on the time domain and the frequency domain for the partial discharge detected through experiments in advance.

The blocking controller 400 may be configured to include a phase signal analysis module, a modulation frequency analysis module, a partial discharge DB module, a diagnostic module, and an event module to perform the partial discharge diagnosis algorithm.

The phase signal analysis module performs a function of analyzing the UHF electromagnetic wave signal detected in the time domain, and maps the detected UHF electromagnetic wave signal to the time domain.

The modulation frequency analysis module performs the function of analyzing the UHF electromagnetic wave signal modulated in the frequency domain. The module modulates the detected UHF electromagnetic wave signal by Fourier transform, and maps the modulated frequency to the frequency domain.

The partial discharge DB module is a database for storing and managing partial discharges detected by type of partial discharge. The partial discharge DB module maps a partial discharge by a floating electrode, a void partial discharge, a creep partial discharge and a corona partial discharge to a time domain and a frequency domain, And build it into a database.

Here, each partial discharge can be converted into a database by using a PD cell that generates a partial discharge.

The diagnostic module compares the information mapped by the phase signal analysis module and the modulation frequency analysis module with the data stored in the partial discharge DB module and detects the partial discharge pattern to diagnose the partial discharge.

In addition, the diagnostic module compares the pattern mapped through the phase signal analysis module with the pattern stored in the partial discharge DB module, compares the pattern mapped through the modulation frequency analysis module with the pattern stored in the partial discharge DB module, The type of partial discharge to the void, the ground surface or the corona is detected and the type of partial discharge for the generated UHF electromagnetic wave signal is diagnosed.

The event module generates an event based on a diagnosis result output from the diagnosis module. That is, the event module outputs a danger signal or a breaker trip signal in a stepwise manner based on a diagnosis result output from the diagnostic module.

The event module may be configured to store and manage the time and diagnosis results of the generated event signal as needed.

The display device 500 displays a detection value and a control status received from the shutoff control device 400 on the screen.

FIG. 10 is a diagram showing a screen displayed on a display device of a partial discharge diagnosis algorithm applied to a 29KV GIS remote diagnosis system equipped with a partial discharge and gas density diagnostic apparatus.

10, a time domain interface 510 in which a UHF electromagnetic wave signal detected through a phase signal analysis module is mapped, a frequency domain interface 520 in which a UHF electromagnetic wave signal modulated through a modulation frequency analysis module is mapped, And a setting interface 530 for operating start, end, time domain, standard deviation range in the frequency domain, and the like.

FIG. 11 is a graph (a) mapped to a time domain interface and a frequency domain interface for a void partial discharge, a graph (b) mapped to a time domain interface and a frequency domain interface for a creep partial discharge, And a graph (c) mapped to the interface and the frequency domain interface.

That is, if the time domain interface for the detected UHF electromagnetic wave signal and the pattern mapped to the frequency domain interface are matched with any one of the patterns shown in FIG. 11, the detected UHF electromagnetic wave is determined as a partial discharge corresponding to the pattern .

According to the present invention, since the partial discharge inside the GIS can be detected and the breaker can be selectively opened or closed according to the detection result, it is possible to prevent burning of the power device and protect the load side.

In addition, there is an advantage that a safety accident against an electric shock or the like can be prevented by detecting and diagnosing the density of the heat transfer gas.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: GIS 100: Partial discharge detection device
110: Sensor flange 120: Sensor support
130: Sensor antenna 140: Sensor cover
150: connector 200: gas density detecting device
210: housing 220:
230: fixing part 240: power applying part
250: first oscillator 255: second oscillator
260: comparison unit 270: output unit
300: breaker operation characteristic detecting device 310: current signal input part
320: contact state signal input unit 330:
400: diagnosis control device 500: display device
510: Time Domain Interface
520: Frequency domain interface
530: Configuration Interface

Claims (5)

A partial discharge detecting device for detecting a partial discharge inside the GIS;
A gas density detecting device for detecting the density of the insulated gas filled in the GIS;
A breaker operation characteristic detecting device for detecting an operation characteristic of the breaker installed in the GIS;
A diagnostic device for diagnosing partial discharge, gas density, and circuit breaker operation characteristics based on data values output from the partial discharge detection device, the gas density detection device, and the circuit breaker operation characteristic detection device; And
A display device for displaying information output from the diagnostic device;
Lt; / RTI >
Wherein the gas density detecting device comprises:
Wherein the density of the insulating gas is detected by a difference between a frequency in a vacuum state and a frequency in a state of being in contact with an insulating gas,
Wherein the gas density detecting device comprises:
A cylindrical housing having a bottom open;
A threaded portion formed on the housing and screwed on the outer surface of the housing of the GIS;
A securing portion for securing a state in which the housing is screwed to the housing by inserting the screw portion into the housing by screwing in a state where the screw portion is screwed to the housing;
A first oscillator installed inside the housing and outputting a frequency by a voltage applied in a vacuum state;
A second oscillator installed inside the housing and outputting a frequency by applying a voltage in a state of being exposed to the insulating gas; And
A comparator for outputting a difference value between the first oscillator and the second oscillator for each frequency, as a current value;
29KV GIS remote diagnosis system with a partial discharge and gas density diagnostic device.
delete The method according to claim 1,
The partial discharge detection device includes:
A sensor flange coupled to an outer surface of the GIS enclosure;
A sensor support coupled to an inner surface of the sensor flange;
A sensor antenna attached to the sensor support;
A sensor cover coupled to the sensor flange at the inside of the GIS enclosure and sealing the outside of the sensor support and the sensor antenna; And
A connector installed on an outer surface of the sensor flange and electrically connected to the sensor antenna to output a signal;
29KV GIS remote diagnosis system with a partial discharge and gas density diagnostic device.
The method according to claim 1,
The breaker operation characteristic detecting device includes:
Wherein a mechanical operation time and a three-phase fault current for a time interval from when the electrical signal is inputted to the trip coil to the completion of the operation of the trip coil according to the tripping signal of the breaker, 29KV GIS Remote Diagnosis System with Discharge and Gas Density Diagnosis Device.
The method of claim 4,
The breaker operation characteristic detecting device includes:
A current signal input unit for inputting an operation current signal of the circuit breaker and a load current signal of the electric power facility;
A contact state signal input unit for inputting a contact state signal of the blocking coil and the closing coil of the circuit breaker; And
A processor for analyzing the operation current signal and the load current signal to calculate data representing an operating characteristic of the circuit breaker;
29KV GIS remote diagnosis system with a partial discharge and gas density diagnostic device.

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