TWI618934B - Partial discharge detecting devices and methods thereof - Google Patents

Abstract

A partial discharge detection device suitable for a high-voltage switchboard includes a first sensor, a second sensor, and a control unit. The functions of the high-voltage switchboard include converting high-voltage power to household power. The first sensor detects a ground current in a first frequency band of a ground line of the high-voltage power supply to generate a first voltage signal. The second sensor detects a microwave signal located in a second frequency band in the high-voltage switchboard to generate a second voltage signal, and the second frequency band is higher than the first frequency band. When the first voltage signal and the second voltage signal occur at the same time, the control unit determines that a partial discharge occurs in the high-voltage switchboard and generates a notification signal.

Description

Partial discharge detection device and method

The invention relates to a partial discharge detection device applied to a high-voltage switchboard during operation, and particularly to a partial discharge detection device applied to reduce surrounding electrical interference to reduce the situation of misjudged partial discharge caused by interference.

Partial discharge refers to the discharge that occurs between the electrodes but does not penetrate the electrodes. Due to defects in the insulator of the equipment or defects caused during production, repeated breakdown of partial discharges will occur under the effect of high electric field strength. The initial partial discharge energy is very small, so the short-term existence does not affect the insulation strength of electrical equipment. However, when partial discharges continue to occur at the operating voltage, these weak discharges will produce a cumulative effect and make the dielectric properties of the insulation. Gradually degrade and enlarge local defects, eventually leading to breakdown of the entire insulator.

Although partial discharge will cause the insulator to deteriorate and cause damage, it takes time to develop. The development time is related to the operating conditions of the device itself, the location of the partial discharge and the insulation structure of the device. Therefore, an efficient partial discharge detection is needed. Device and method.

In view of this, the present invention proposes a partial discharge detection device suitable for a high-voltage switchboard, wherein the functions of the high-voltage switchboard include converting a high-voltage power source to a household power source, including: a first sensor, a second sensor And a control unit. The first sensor detects a ground current of a ground line of the high-voltage power supply and a ground current in a first frequency band to generate a first voltage signal. The second sensor detects a microwave signal located in a second frequency band in the high-voltage switchboard and generates a second voltage signal, wherein the second frequency band is higher than the first frequency band. When the first voltage signal and the second voltage signal occur simultaneously, the control unit determines that a partial discharge has occurred in the high-voltage switchboard and generates a notification signal.

According to an embodiment of the present invention, the partial discharge detection device further includes: a signal transmission interface. The signal transmission interface is coupled between the control unit and an input-output device. The signal transmission interface is used to transmit the notification signal to the input-output device, and to transmit an input signal of one of the input-output devices to the control. unit.

According to an embodiment of the present invention, the partial discharge detection device further includes: an analog digital converter. The analog-to-digital converter includes a first filter amplifier circuit, a first comparison circuit, a second filter amplifier circuit, and a second comparison circuit. The first filter amplifier circuit filters the first voltage signal and amplifies the noise outside the first frequency band to generate a first amplified signal. When the first amplified signal is greater than a first trigger level, the first comparison circuit generates a first trigger signal. The second filter amplifier circuit filters the second voltage signal and amplifies the noise outside the second frequency band to generate a second amplified signal. When the second amplified signal is greater than a second trigger level, the second comparison circuit generates a second trigger signal, wherein when the first trigger signal and the second trigger signal are When the numbers occur simultaneously, the control unit generates the notification signal.

According to an embodiment of the present invention, the input / output device further includes: a setting module and a display module. The setting module is configured to set the first trigger level and the second trigger level to generate the input signal, wherein the control unit provides the first trigger level to the first comparison circuit according to the input signal and The second trigger level is provided to the second comparison circuit. The display module generates a warning message according to the notification signal.

According to an embodiment of the present invention, the analog-to-digital converter further includes: a power phase acquisition circuit. The power phase extraction circuit acquires phase information of the high-voltage power and generates a phase signal, wherein the control unit determines whether the partial discharge occurs at a specific phase of the high-voltage power according to the phase signal, and when it is determined that the partial discharge occurs At the specific phase, the control unit counts one occurrence frequency of the partial discharge, and when the occurrence frequency increases, the control unit sends the notification signal.

According to another embodiment of the present invention, when the power phase acquisition circuit captures a home phase of one of the household power sources, the control unit determines phase information of the high-voltage power source based on a phase difference and the household phase, wherein the setting mode is The group is further used to set the phase difference.

The invention further proposes a partial discharge detection method, which is suitable for a partial discharge detection device to detect a high-voltage power distribution board, wherein the function of the high-voltage power distribution board includes converting a high-voltage power supply to a household power supply, including: A grounding current from a ground wire generates a first voltage signal, wherein the grounding current is located in a first frequency band; detecting a microwave signal in the high-voltage distribution board generates a second voltage signal, wherein the microwave signal is located at a Second band, above The second frequency band is higher than the first frequency band; and when the first voltage signal and the second voltage signal occur at the same time, it is determined that a partial discharge occurs in the high-voltage switchboard and a notification signal is generated.

According to an embodiment of the present invention, the partial discharge detection method further includes: receiving an input signal through an input / output device; and transmitting an input signal of one of the input / output devices to the partial discharge detection device.

According to an embodiment of the present invention, the step of determining that the high-voltage switchboard has the partial discharge and generating the notification signal includes: filtering out the first voltage signal and amplifying the noise outside the first frequency band to generate a first signal; An amplified signal; when the first amplified signal is greater than a first trigger level, a first trigger signal is generated; the second voltage signal is filtered and amplified after noise outside the second frequency band to generate a second signal Amplified signal; when the second amplified signal is greater than a second trigger level, a second trigger signal is generated; and

When the first trigger signal and the second trigger signal occur simultaneously, the notification signal is generated.

According to an embodiment of the present invention, the partial discharge detection method further includes: using the input / output device to input the first trigger level and the second trigger level to generate the input signal; and according to the notification signal, using the above The input-output device generates a warning message.

According to an embodiment of the present invention, the step of judging the occurrence of the partial discharge of the high-voltage switchboard and generating the notification signal includes: acquiring phase information of the high-voltage power supply to generate a phase signal; and determining whether the partial discharge occurs according to the phase signal. At a specific phase of the high voltage power supply; when the partial discharge occurs at the specific phase, counting the frequency of occurrence of one of the partial discharges; And when the occurrence frequency increases, the notification signal is issued.

According to an embodiment of the present invention, the step of judging the occurrence of the partial discharge of the high-voltage switchboard and generating the notification signal further includes: capturing a home phase of the household power source; and judging the high voltage based on a phase difference and the home phase. The phase information of the power supply, wherein the phase difference is input by the input / output device.

10‧‧‧ High-voltage switchboard

100, 200‧‧‧ partial discharge detection device

101, 201‧‧‧first sensor

102, 202‧‧‧Second sensor

103, 203‧‧‧ Control Unit

204‧‧‧Signal transmission interface

210‧‧‧ Analog Digital Converter

211‧‧‧first filter amplifier circuit

212‧‧‧Second filter amplifier circuit

213‧‧‧First comparison circuit

214‧‧‧Second comparison circuit

215‧‧‧ Power phase acquisition circuit

250‧‧‧ input and output devices

251‧‧‧setting module

252‧‧‧Display Module

SV1‧‧‧First voltage signal

SV2‧‧‧Second voltage signal

SA1‧‧‧First amplified signal

SA2‧‧‧Second amplified signal

ST1‧‧‧First trigger signal

ST2‧‧‧Second trigger signal

TR1‧‧‧First trigger level

TR2‧‧‧Second trigger level

SP‧‧‧phase signal

SI‧‧‧ input signal

SN‧‧‧Notification signal

PH‧‧‧High Voltage Power Supply

PM‧‧‧Home Power

FIG. 1 is a block diagram showing a partial discharge detection device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a partial discharge detection device according to another embodiment of the present invention.

FIG. 3 is a flowchart illustrating a partial discharge detection method according to an embodiment of the present invention.

The following description is an embodiment of the present invention. Its purpose is to exemplify the general principles of the present invention and should not be regarded as a limitation of the present invention. The scope of the present invention shall be defined by the scope of the patent application.

It is worth noting that the following disclosure can provide multiple embodiments or examples for practicing different features of the present invention. The special component examples and arrangements described below are only used to briefly explain the spirit of the present invention, and are not intended to limit it. The scope of the invention. In addition, the following description may reuse the same component symbols or text in multiple examples. However, the purpose of reuse is only to provide a simplified and clear description, and not to limit the relationship between the multiple embodiments and / or configurations discussed below. In addition, the description that one feature described in the following specification is connected to, coupled to, and / or formed on another feature may actually include many different embodiments, including direct contact of such features, or other additional features. The features are formed between the features and so on, so that the features are not in direct contact.

FIG. 1 is a block diagram showing a partial discharge detection device according to an embodiment of the present invention. As shown in FIG. 1, the partial discharge detection device 100 includes a first sensor 101, a second sensor 102, and a control unit 103. The partial discharge detection device 100 is placed in a high-voltage switchboard 10. According to an embodiment of the present invention, the main function of the high-voltage switchboard 10 is to transmit and distribute the power of the user terminal, wherein distributing the power of the user terminal includes converting the high-voltage power source PH to a household power source PM.

The first sensor 101 is configured to detect a ground current generated by a ground wire of the high-voltage power supply PH due to a partial discharge, and generate a first voltage signal SV1 that can be processed by a circuit. The ground current is located in a first frequency band. The second sensor 102 is used to detect a microwave signal generated in the high-voltage switchboard 10 due to a partial discharge and generate a second voltage signal SV2 that can be processed by the circuit. The microwave signal is located in the second frequency band.

According to an embodiment of the present invention, the first frequency band is the HF frequency band (3MHz-30MHz) and the VHF frequency band (30MHz-300MHz), and the second frequency band is the UHF frequency band (300MHz-3GHz). According to other embodiments of the present invention, the first frequency band and the second frequency band may be other frequency bands, wherein the second frequency band is higher than the first frequency band.

According to an embodiment of the present invention, the first sensor 101 is a detecting factor. The high-frequency current transformer (HFCT) of the transient pulse current signal generated by the partial discharge of the high-voltage switchboard 10 and the ground wire of the high-voltage power supply PH. The second sensor 102 is a device for detecting partial discharge. Ultra-High Frequency Antenna of the generated microwave signal.

When a partial discharge occurs in the high-voltage switchboard 10, the ground line of the high-voltage power supply PH will generate a transient pulse current, and it is often accompanied by a microwave signal generated in the high-voltage switchboard 10. Therefore, when the first voltage signal SV1 and the second voltage signal SV2 are generated at the same time It means that a partial discharge does occur in the high-voltage switchboard 10, and the control unit 103 can determine that a partial discharge has occurred in the high-voltage switchboard 10 and generate a notification signal SN.

According to other embodiments of the present invention, the first sensor 101 and the second sensor 102 may also be an acoustic sensor (AE Sensor), a transient ground voltage sensor (TEV Sensor), and a ground current sensor. (HFCT Sensor) and microwave sensor (UHF Sensor), the control unit 103 generates the first voltage signal SV1 and the second voltage simultaneously and separately according to the first sensor 101 and the second sensor 102. Signal SV2, it is determined that a partial discharge does occur within the high-voltage switchboard 10, and a notification signal SN is generated.

FIG. 2 is a block diagram of a partial discharge detection device according to another embodiment of the present invention. As shown in FIG. 2, the partial discharge detection device 200 includes a first sensor 201, a second sensor 202, an analog-to-digital converter 210, a control unit 203, a signal transmission interface 204, and an input-output device 250. A sensor 201, a second sensor 202, and a control unit 203 correspond to the first sensor 101, the second sensor 102, and the control unit 103 in FIG. 1 respectively.

Comparing Fig. 2 with Fig. 1, the first sensor 201, the second sensor 202, and the control unit 203 have an analog-to-digital converter 210. The analog-to-digital converter 210 The bit converter 210 includes a first filter amplifier circuit 211, a second filter amplifier circuit 212, a first comparison circuit 213, a second comparison circuit 214, and a power phase extraction circuit 215.

The first filtering and amplifying circuit 211 filters out the noise of the first voltage signal SV1 outside the first frequency band and amplifies it to improve the resolution of the back-end first comparison circuit 213 to generate a first amplified signal SA1. When the first amplified signal SA1 is greater than the first trigger level TR1, the first comparison circuit 213 generates a first trigger signal ST1. According to an embodiment of the present invention, the first trigger level TR1 is used to set a trigger threshold, so that the control unit 203 analyzes the use of partial discharge.

The second filtering and amplifying circuit 212 filters the noise of the second voltage signal SV2 outside the second frequency band and amplifies it to improve the resolution of the second comparison circuit 214 at the back end to generate a second amplified signal SA2. When the second amplified signal SA2 is greater than the second trigger level TR2, the second comparison circuit 214 generates a second trigger signal ST2. According to an embodiment of the present invention, the second trigger level TR2 is used to set a trigger threshold, so that the control unit 203 analyzes the use of partial discharge.

When the first trigger signal ST1 and the second trigger signal ST2 occur at the same time, both the transient pulse current and the microwave signal in the high-voltage switchboard 10 are higher than the threshold value. Therefore, the control unit 203 controls the ST2, it is determined that a partial discharge occurs in the high-voltage switchboard 10 and a notification signal SN is generated.

The power phase acquisition circuit 215 is used for acquiring phase information of the high-voltage power source PH in FIG. 1 to generate a phase signal SP, and transmits the phase signal SP to the control unit 203. According to an embodiment of the present invention, the control unit 203 determines whether the occurrence time of the partial discharge conforms to a specific phase due to the partial discharge according to the phase information, and calculates the occurrence frequency of the partial discharge. When the occurrence frequency increases, the control unit sends a notification signal SN To the input-output device 250.

According to an embodiment of the present invention, for example, the partial discharge is more likely to occur at a phase between 0 and 90 degrees and between 180 and 270 degrees of the high-voltage power source PH. When the control unit 203 confirms that the partial discharge occurs at a phase between 0 to 90 degrees or 180 to 270 degrees of the high-voltage power source PH, it adds one to the count of the counter and counts the number of partial discharges within a predetermined time and counts them. Is the frequency of occurrence. When the control unit 203 determines that the frequency increase occurs, it sends a notification signal SN to the input / output device 250 to prevent the occurrence of a power failure accident of the high-voltage equipment without warning in advance.

According to another embodiment of the present invention, the power phase acquisition circuit 215 can also capture the home phase of the home power PM shown in FIG. 1 and send it to the control unit 203. The control unit 203 determines the phase information of the high-voltage power source PH according to the phase difference between the high-voltage power source PH and the household power source PM and the home phase. The input method of the phase difference will be described in detail below.

The signal transmission interface 204 is coupled between the control unit 203 and the input-output device 250 for transmitting the notification signal SN of the control unit 203 to the input-output device 250 and the input signal SI of the input-output device 250 to the control unit 203 .

As shown in FIG. 2, the input / output device 250 includes a setting module 251 and a display module 252. The setting module 251 is used to set the first trigger level TR1 and the second trigger level TR2 to generate an input signal SI. The input signal SI is transmitted to the control unit 203 through the signal transmission interface 204, so that the control unit 203 sends the input signal SI according to the input signal SI. The first trigger level TR1 is provided to the first comparison circuit 213 and the second trigger level TR2 is provided to the second comparison circuit 214.

According to an embodiment of the present invention, the user can set the thresholds of the first comparison circuit 213 and the second comparison circuit 214 through the setting module 251 to filter the background. Influence of scene noise on judgment of partial discharge. According to another embodiment of the present invention, the setting module 251 can set the phase difference between the high-voltage power source PH and the household power source PM, and transmit the phase difference to the control unit 203 through the input signal SI. According to an embodiment of the present invention, the setting module 251 may be a touch button or a touch panel.

The display module 252 generates a warning message according to the notification signal SN sent from the control unit 203 to notify the user of the use of the high-voltage switchboard 10 in FIG. 1. According to some embodiments of the present invention, the display module 252 may be a liquid crystal display, a warning light, or a buzzer.

FIG. 3 is a flowchart illustrating a partial discharge detection method according to an embodiment of the present invention. The following description of the flowchart in FIG. 3 will be combined with FIG. 1 to facilitate detailed description.

As shown in FIG. 3, the first sensor 101 of FIG. 1 is used to detect the ground current of the ground line of the high-voltage power source PH in the first frequency band to generate a first voltage signal SV1 (step S1). At the same time, the second sensor 102 in FIG. 1 is used to detect the microwave signal located in the second frequency band in the high-voltage switchboard 10 in FIG. 1 to generate a second voltage signal SV2 (step S2).

It is determined whether the first voltage signal SV1 and the second voltage signal SV2 occur simultaneously (step S3); when the first voltage signal SV1 and the second voltage signal SV2 occur simultaneously, it is determined whether a partial discharge occurs in the high-voltage switchboard 10 (step S4). If not, return to step S1 and step S2 to continue detection.

What has been described above are the general features of the embodiment. Those of ordinary skill in the art should be able to easily use the present invention as a basis for designing or adjusting to achieve the same purpose and / or achieve the same advantages of the embodiments described herein. Those with ordinary knowledge in the technical field should also understand that the same configuration should not deviate from this creation. Spirit and scope, without departing from the spirit and scope of this creation, they can make various changes, replacements and alternations. The illustrative methods represent only exemplary steps, but the steps are not necessarily required to be performed in the order indicated. Additional steps may be added, replaced, changed, and / or eliminated to adjust as appropriate, and are consistent with the spirit and scope of the disclosed embodiments.

10‧‧‧ High-voltage switchboard

100‧‧‧ partial discharge detection device

101‧‧‧first sensor

102‧‧‧Second sensor

103‧‧‧Control unit

SV1‧‧‧First voltage signal

SV2‧‧‧Second voltage signal

SN‧‧‧Notification signal

PH‧‧‧High Voltage Power Supply

PM‧‧‧Home Power

Claims (12)

A partial discharge detection device suitable for a high-voltage switchboard, wherein the functions of the high-voltage switchboard include converting a high-voltage power supply to a household power supply, including: a first sensor that detects the location of a ground wire of the high-voltage power supply A first voltage signal is generated by a ground current in a first frequency band; a second sensor detects a microwave signal located in a second frequency band in the high-voltage switchboard and generates a second voltage signal, wherein the first The second frequency band is higher than the first frequency band; and a control unit, when the first voltage signal and the second voltage signal occur at the same time, determine that a partial discharge occurs in the high-voltage switchboard and generate a notification signal. The partial discharge detection device according to item 1 of the patent application scope further includes: a signal transmission interface coupled between the control unit and an input / output device, wherein the signal transmission interface is used to transmit the notification signal. To the input / output device, and transmitting one of the input signals of the input / output device to the control unit. The partial discharge detection device according to item 2 of the scope of patent application, further includes: an analog digital converter, including: a first filter amplifier circuit, which filters out noise of the first voltage signal outside the first frequency band Then amplify it to generate a first amplified signal; A first comparison circuit generates a first trigger signal when the first amplified signal is greater than a first trigger level; a second filter amplifier circuit filters out noise of the second voltage signal outside the second frequency band And then amplify it to generate a second amplified signal; and a second comparison circuit that generates a second trigger signal when the second amplified signal is greater than a second trigger level, wherein when the first trigger signal and the first When two trigger signals occur simultaneously, the control unit generates the notification signal. The partial discharge detection device according to item 3 of the scope of patent application, wherein the input / output device further includes: a setting module for setting the first trigger level and the second trigger level to generate the input signal. Wherein the control unit provides the first trigger level to the first comparison circuit and the second trigger level to the second comparison circuit according to the input signal; and a display module according to the notification signal A warning message is generated. The partial discharge detection device according to item 4 of the scope of the patent application, wherein the analog-to-digital converter further includes: a power phase acquisition circuit that acquires phase information of the high-voltage power supply to generate a phase signal, wherein the control unit Determining whether the partial discharge occurs at a specific phase of the high-voltage power supply according to the phase signal, and when determining that the partial discharge occurs at the specific phase, the control The unit counts the occurrence frequency of one of the partial discharges, and when the occurrence frequency increases, the control unit sends the notification signal. According to the partial discharge detection device described in the fifth item of the patent application scope, wherein when the power supply phase acquisition circuit captures a home phase of the home power supply, the control unit determines the high voltage power supply based on a phase difference and the home phase. Phase information, wherein the setting module is further configured to set the phase difference. A partial discharge detection method is suitable for a partial discharge detection device to detect a high-voltage switchboard. The functions of the high-voltage switchboard include converting a high-voltage power supply to a household power supply, including: detecting a ground wire of one of the high-voltage power supplies. A ground current generates a first voltage signal, wherein the ground current is located in a first frequency band; detecting a microwave signal in the high-voltage distribution board generates a second voltage signal, wherein the microwave signal is located in a second frequency band, The second frequency band is higher than the first frequency band; and when the first voltage signal and the second voltage signal occur at the same time, it is determined that a partial discharge occurs in the high-voltage distribution board and a notification signal is generated. The partial discharge detection method according to item 7 of the scope of patent application, further comprising: receiving an input signal through an input / output device; and transmitting an input signal of one of the input / output devices to the partial discharge detection device. The partial discharge detection method according to item 8 of the scope of the patent application, wherein the step of judging the occurrence of the partial discharge of the high-voltage switchboard and generating the notification signal includes filtering out the impurities of the first voltage signal outside the first frequency band. After the signal is amplified, a first amplified signal is generated; when the first amplified signal is greater than a first trigger level, a first trigger signal is generated; and the noise of the second voltage signal outside the second frequency band is filtered out And then amplify it to generate a second amplified signal; when the second amplified signal is greater than a second trigger level, a second trigger signal is generated; and when the first trigger signal and the second trigger signal occur at the same time, The above notification signal is generated. The partial discharge detection method according to item 9 of the scope of patent application, further comprising: using the input / output device to input the first trigger level and the second trigger level to generate the input signal; and according to the notification signal , Using the input-output device to generate a warning message. The partial discharge detection method according to item 10 of the scope of patent application, wherein the step of judging the occurrence of the partial discharge of the high-voltage switchboard and generating the notification signal includes: Retrieve phase information of the high-voltage power supply to generate a phase signal; determine whether the partial discharge occurs at a specific phase of the high-voltage power supply according to the phase signal; when the partial discharge occurs at the specific phase, count one of the partial discharges The frequency of occurrence; and when the frequency of occurrence increases, the notification signal is issued. The partial discharge detection method according to item 11 of the scope of patent application, wherein the step of judging the occurrence of the partial discharge of the high-voltage switchboard and generating the notification signal further includes: capturing a home phase of one of the household power sources; and according to a phase The phase information of the high-voltage power source, and the phase of the household, and the phase difference is input by the input / output device.