KR102801525B1 - Bushing tap adapter and bushing tap floating troubleshooting system - Google Patents

Abstract

The bushing tap adapter of the present invention may include: an adapter frame that can be connected to a bushing tap of a power facility such as a transformer; a protection element built into the adapter frame and grounding an internal circuit of the adapter frame in the event of an overvoltage failure; a field alarm unit for notifying a field worker of the operation of the protection element; and a server alarm unit for notifying a server for the bushing diagnosis means of the operation of the protection element.

Description

{BUSHING TAP ADAPTER AND BUSHING TAP FLOATING TROUBLESHOOTING SYSTEM}

The present invention relates to a bushing tap adapter and a bushing tap floating fault diagnosis system constituting a protection device and a diagnosis system for preventing a bushing tap floating fault.

Figure 1 illustrates the configuration of a typical transformer bushing, a bushing tap adapter, and an online diagnostic system utilizing the same.

The bushing tap is a terminal installed to measure insulation deterioration of a condenser-type transformer bushing. It exists to diagnose the insulation condition inside the bushing by measuring the values of C1 of the main insulating layer, which is a capacitance formed between a conductor and ground as shown in Fig. 1 by crossing the insulating paper and the metal sheet, and C2 of the tab insulating layer, which is formed between the conductor and the outermost metal sheet.

In particular, since C2 is designed to be insulated from the outer case, the ground, if the transformer is operated in an ungrounded state, the tap terminal may float, causing C2 to deteriorate due to overvoltage stress between the lead terminal and the ground, and resulting insulation breakdown.

For the above reasons, when not measuring capacitance in everyday situations, ground the lead-in terminal using a metal cover (cap) that is electrically connected to the case ground, and when performing bushing online diagnosis in diagnostic situations, incorporate an overvoltage protection element inside the bushing tap adapter so that the circuit can be grounded in the event of a failure.

When a tap floating breakdown occurs, a localized and sustained arc occurs between the bushing tap withdrawal terminal and the tap adapter, which may cause the transformer insulation breakdown failure due to tap adapter damage and deterioration of C2 insulation performance.

As the comprehensive preventive diagnosis system for substations is expanded and distributed, online diagnosis of bushings using bushing tap adapters is introduced to monitor insulation deterioration and determine its condition.

Conventionally, a CT sensor for measuring insulation deterioration is passed through the bushing tap lead cable, the end is grounded, and a protective element such as a varistor is built into the bushing tap adapter to prevent tap floating failure.

However, for bushing diagnosis, there is no way to recognize the defective connection/grounding status related to the bushing tap adapter, making it impossible to determine the occurrence of floating due to poor cable connection, poor construction, or physical damage to internal circuits/protective elements.

If the facility operator continues to operate the facility for a long period of time without being aware of this, the leakage current will rapidly increase due to the deterioration of the bushing insulation performance, which will increase the electrical and thermal stress on the protection element, which may cause the element to be short-circuited or destroyed, and this may ultimately lead to the destruction of the bushing insulation.

[Bushing insulation breakdown] in the above tab can be a factor in the air injection of internal insulating oil, and the insulating oil injected in the form of vapor can cause a fire if it comes into contact with a high-temperature arc.

For example, if the protective element operates in a floating state without grounding due to the bushing tap adapter not being properly fastened, the diagnostic device cannot recognize the floating state, and in this situation, if an overvoltage due to a surge, etc. occurs, the protective element itself may be damaged, which may result in a great danger.

Therefore, in order to prevent major transformer failures, an effective bushing tap floating diagnosis and judgment technology is required while the above bushing tap adapter is connected.

Republic of Korea Registration No. 10-2324788

The present invention seeks to provide a bushing tap adapter and a bushing tap floating fault diagnosis system capable of preventing bushing tap floating in advance.

A bushing tap adapter according to one aspect of the present invention may include: an adapter frame that can be connected to a bushing tap of a power facility such as a transformer; a protection element built into the adapter frame and grounding an internal circuit of the adapter frame in the event of an overvoltage failure; a field alarm unit for notifying a field worker of the operation of the protection element; and a server alarm unit for notifying a server for the bushing diagnosis means of the operation of the protection element.

Here, the protection element may include a main protection element that is turned on when an overvoltage fault occurs; and a monitoring protection element that is connected in parallel with the main protection element and in series with the field alarm unit or the server alarm unit.

Here, the adapter frame may further include a bushing tab connection located at one end thereof and mechanically connected to the bushing tab; and a cable connection located at the other end thereof and connected to a cable that mediates the bushing diagnostic device so as to enable data communication with an external bushing diagnostic device.

Here, the field alarm unit may include an LED that emits light when the turn-on current of the monitoring unit protection element is conducted; and a snubber resistor that adjusts voltage distribution to the LED.

Here, the server alarm unit may include a relay contact in which the turn-on current of the monitoring unit protection element operates the contact through the winding inside the relay contact to generate a digital contact signal.

Here, the device further includes a DC rectifier circuit connected to both ends of the protection device and generating DC power in a turn-on state of the protection device, and the on-site alarm unit can be operated by the DC power provided by the DC rectifier circuit.

A bushing tap floating fault diagnosis system according to another aspect of the present invention may include a bushing tap adapter which is connected to a bushing tap of a power facility and has a protection element which grounds a circuit in the event of an overvoltage fault, a field alarm unit for notifying a field worker of the operation of the protection element, and a server alarm unit for notifying an operator server for the bushing diagnosis means of the operation of the protection element; a bushing diagnosis device which is connected to the bushing tap adapter and diagnoses the bushing tap by measuring electrical characteristics; and an operator server which diagnoses the bushing and the power facility from electrical characteristic information transmitted from the bushing diagnosis device.

Here, the bushing tap adapter may further include: an adapter frame that can be connected to a bushing tap of a power facility such as a transformer; a bushing tap connection portion located at one end of the adapter frame and mechanically connected to the bushing tap; and a cable connection portion located at the other end of the adapter frame and to which a cable that mediates the bushing diagnostic device is connected so as to enable data communication with an external bushing diagnostic device.

Here, the protection element may include a main protection element that is turned on when an overvoltage fault occurs; and a monitoring protection element that is connected in parallel with the main protection element and in series with the field alarm unit or the server alarm unit.

Here, the field alarm unit may include an LED that emits light when the turn-on current of the monitoring unit protection element is conducted; and a snubber resistor that adjusts voltage distribution to the LED.

Here, the server alarm unit may include a relay contact in which the turn-on current of the monitoring unit protection element operates the contact through the winding inside the relay contact to generate a digital contact signal.

Here, the device further includes a DC rectifier circuit connected to both ends of the protection device and generating DC power in a turn-on state of the protection device, and the on-site alarm unit can be operated by the DC power provided by the DC rectifier circuit.

By implementing the bushing tap adapter and/or bushing tap floating fault diagnosis system according to the invention of the above-described configuration, there is an advantage in that bushing tap deterioration can be detected in advance, thereby contributing to preventing bushing tap insulation breakdown failure and major transformer failure.

The bushing tap adapter and/or bushing tap floating fault diagnosis system according to the invention has the advantage of being able to prevent tap floating in advance, particularly due to poor cable contact, poor construction, circuit damage caused by external impact during inspection, short circuit due to component deterioration, etc.

The bushing tap adapter and/or bushing tap floating fault diagnosis system according to the invention has the advantage of significantly reducing the failure rate of power equipment, particularly transformers.

Figure 1 is a circuit diagram showing the configuration of a typical transformer bushing, a bushing tap adapter, and an online diagnostic system utilizing the same.
FIG. 2 is a block diagram illustrating the functional blocks of an online diagnostic system that applies a bushing tap adapter floating diagnostic device to a bushing tap adapter according to the idea of the present invention.
FIG. 3 is a circuit diagram illustrating a bushing tap adapter according to the invention, centered on a bushing tap floating diagnostic circuit.
Fig. 4 is a circuit diagram showing an example of implementing the bushing tap adapter of Fig. 3 as a monitoring unit and system configuration using a high-brightness LED and relay circuit.
Fig. 5 is a circuit diagram showing an example of implementing the bushing tap adapter of Fig. 2 in the form of a bushing tap floating diagnostic device using a DC rectifier circuit.

In describing the present invention, terms such as first, second, etc. may be used to describe various components, but the components may not be limited by the terms. The terms are only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

When it is said that a component is connected or coupled to another component, it can be understood that it may be directly connected or coupled to that other component, but there may also be other components in between.

The terminology used in this specification is only used to describe specific embodiments and is not intended to limit the invention. The singular expression may include the plural expression unless the context clearly indicates otherwise.

In this specification, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, and can be understood as not excluding in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

Additionally, the shape and size of elements in the drawing may be exaggerated for clearer explanation.

The present invention deals with a protection circuit and device for diagnosing bushing tab floating, and enables an operator to determine whether the tab is abnormal by electrically and visually indicating a protection element that operates during floating.

FIG. 2 is a block diagram illustrating the functional blocks of an online diagnostic system that applies a bushing tap adapter floating diagnostic device to a bushing tap adapter according to the idea of the present invention.

As a tap floating diagnostic device according to the idea of the present invention, a bushing tap adapter is composed of a visual monitoring unit and an electrical monitoring unit as shown in Fig. 2, and is configured to be linked with a bushing diagnostic device (140) and an operator server (160) as an existing bushing online diagnostic system, so that an operator can simultaneously check the bushing online insulation deterioration measurement value and whether the bushing tap is floating.

The bushing tap floating fault diagnosis system illustrated in FIG. 2 may include a bushing tap adapter (120) which is connected to a bushing (18) tap of a power facility and has a protection element for grounding a circuit in the event of an overvoltage fault, a field alarm unit for notifying a field worker of the operation of the protection element, and a server alarm unit for notifying an operator server for the bushing diagnosis means of the operation of the protection element; a bushing diagnosis device (140) which is connected to the bushing tap adapter and measures and diagnoses the electrical characteristics of the bushing tap; and an operator server (160) which diagnoses the bushing (18) and the power facility from electrical characteristic information transmitted from the bushing diagnosis device (140).

FIG. 3 is a circuit diagram illustrating a bushing tap adapter according to the invention, centered on a bushing tap floating diagnostic circuit.

A bushing tap adapter (120) as shown in FIGS. 2 and 3 may include: an adapter frame that can be connected to a bushing (18) tap of a power facility such as a transformer; a protection element built into the adapter frame that grounds an internal circuit of the adapter frame in the event of an overvoltage failure; a field alarm unit for notifying a field worker of the operation of the protection element; and a server alarm unit for notifying a server for the bushing diagnosis means of the operation of the protection element.

According to the implementation, the bushing tab adapter (120) may further include a bushing tab connection portion located at one end of the adapter frame and mechanically connected to the bushing tab; and a cable connection portion located at the other end of the adapter frame and to which a data communication cable, such as a coaxial cable that mediates the bushing diagnostic device, is connected so as to enable data communication with an external bushing diagnostic device.

In Fig. 3, the protection element includes a main protection element (121) that is turned on when an overvoltage fault occurs; and a monitoring protection element (122) that is connected in parallel with the main protection element (121) and connected in series with the field alarm unit or the server alarm unit.

For example, the main protection element (121) and/or the monitoring protection element (122) may be implemented as a varistor that is turned on by a predetermined reference potential difference.

The bushing diagnostic means (140) is connected to the bushing tap adapter (120) and can measure and diagnose the electrical characteristics of the bushing tap.

The above main protection element (121) and/or the monitoring protection element (122) can protect the circuit of the bushing diagnostic means by grounding it together with the internal circuit in the event of an overvoltage failure.

The circuit configuration of the bushing tap adapter device proposed according to the idea of the present invention is exemplified in FIG. 3. Inside the tap (120) of the illustrated bushing tap adapter device, a main protection device (121), which is a conventional overvoltage protection device, and a monitoring protection device (122) are configured in parallel, and a visual monitoring device (124) as the field alarm device and an electrical monitoring device (126) as the server alarm device are connected in series and parallel between the monitoring protection device (122) and ground. In another implementation, each monitoring device (124, 126) can be applied individually.

When the tab (18) is floating, the voltage applied to the main protection element (121) and the monitoring protection element (122) is the same, and can be configured to operate sequentially or simultaneously depending on the system configuration.

For example, during simultaneous operation, the main protection element (121) can suppress the occurrence of primary overvoltage, and the monitoring protection element (122) can perform a function to notify the user that tap floating has occurred by conducting the visual monitoring unit (124) and the electrical monitoring unit (126).

Depending on the implementation, the visual surveillance unit (124) may be replaced by other means such as an auditory surveillance unit, or may be configured in a form selected from various means for visual surveillance.

For example, the visual monitoring unit (124) may use a light-emitting diode element that is visually recognizable, such as a high-brightness LED, and in this case, when floating occurs, a voltage higher than a certain level applied to the light-emitting element conducts the element and lights it up, and the operator can determine whether tap floating occurs by checking whether it lights up.

As the above server alarm unit, the electrical monitoring unit (126) can be configured in a form selected from various types of circuit conduction detection and notification means.

For example, the electrical monitoring unit (126) may apply a relay or the like configured as a contact circuit, and in this case, when floating occurs, the contact operates to generate an electrical digital signal, and this is linked to the bushing online diagnostic system to notify the operator through a notification function such as an alarm, so that tap floating can be determined.

Fig. 4 is a circuit diagram showing an example of implementing the bushing tap adapter device of Fig. 3 as a monitoring unit and system configuration using a high-brightness LED and a relay circuit (AC type).

The embodiment illustrated in Fig. 4 has a visual monitoring unit (124-1, 125) equipped with a high-brightness LED (124-1), and an electrical monitoring unit (126-1) configured as a relay circuit.

The visual monitoring unit (124-1, 125) configured in the city has a snubber resistor (125) connected in series to prevent overvoltage applied to the LED (124-1) voltage distribution and the element, and can perform an on-site alarm by having the high-brightness LED (124-1) turn on and light up according to the operation of the monitoring unit protection element (122) due to the occurrence of floating.

The electrical monitoring unit (126-1) shown in the figure is composed of a relay contact, and when the monitoring unit protection element (122) operates, the current flowing through the coil inside the relay contact operates the contact to generate a digital contact signal. The generated digital signal is transmitted to the signal processing unit (146) of the diagnostic system to generate an alarm for the server (160).

Fig. 5 is a circuit diagram showing an example of implementing the bushing tap adapter device of Fig. 2 in the form of a bushing tap floating diagnostic device using a DC rectifier circuit (DC type).

Another embodiment illustrated in Fig. 5 is a structure in which the power supply for the monitoring unit of the bushing tap adapter (120-2) is supplied as DC power, and a DC full-wave rectifier circuit (123-2) is installed at both ends of the main protection element (121-2), so that the visual monitoring unit (124-2) and the electrical monitoring unit (126-2) can operate through DC power.

The method based only on AC as shown in Fig. 4 may cause repeated switching of the visual monitoring unit and the electrical monitoring unit, resulting in repeated flashing, but the method as shown in Fig. 5 has the advantage of being able to continuously light the visual monitoring unit and generate digital signals from the electrical monitoring unit by applying a DC power source capable of full-wave rectification.

Meanwhile, in another embodiment of the present invention of another implementation, a tap floating diagnostic device may be configured by individually applying a visual monitoring unit or an electrical monitoring unit inside the AC type and DC type bushing tap adapters described above.

Those skilled in the art should understand that the present invention can be implemented in other specific forms without changing the technical idea or essential characteristics thereof, and that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the claims described below rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

120 : Bushing tap adapter
121 : Main protection element
122: Surveillance protection device
124 : Visual Surveillance Unit
126 : Electrical Monitoring Unit
140 : Bushing diagnostic tool
160 : Operator Server

Claims (12)

An adapter frame that can be connected to the bushing tap of a power installation;
A protection element built into the above adapter frame and grounding the internal circuit of the above adapter frame in the event of an overvoltage failure;
A field alarm unit for notifying field workers of the operation of the above protection device; and
A server alarm unit that reports the operation of the above protection device to the server for diagnosis of the above bushing.
Including,
The above protection device is,
A main protection element that turns on in the event of an overvoltage fault; and
It includes a monitoring protection element connected in parallel with the above main protection element and connected in series with the field alarm unit or the server alarm unit,
Between the above-mentioned monitoring unit protection device and the ground, a visual monitoring unit as the above-mentioned field alarm unit and an electrical monitoring unit as the above-mentioned server alarm unit are connected.
A bushing tap adapter in which the above-mentioned monitoring unit protection element performs a function of notifying the user that tap floating has occurred by conducting the above-mentioned visual monitoring unit and the above-mentioned electrical monitoring unit.
delete In the first paragraph,
A bushing tab connection located at one end of the above adapter frame and mechanically connected to the above bushing tab;
A (coaxial) cable connection portion located at the other end of the above adapter frame, to which a cable that mediates the above bushing diagnostic device is connected so that data communication with an external bushing diagnostic device is possible.
Bushing tap adapter including more.
In the first paragraph,
The above on-site alarm unit,
An LED that emits light when the turn-on current of the above-mentioned monitoring unit protection element is conducted; and
Snubber resistor to adjust voltage distribution to the above LED
Bushing tap adapter including:
In paragraph 4,
The above server alarm section,
A relay contact in which the turn-on current of the above-mentioned monitoring unit protection element operates the contact through the winding inside the relay contact to generate a digital contact signal.
Bushing tap adapter including:
In the first paragraph,
A DC rectifier circuit connected to both ends of the above protection element and generating DC power when the above protection element is turned on.
Including more,
The above on-site alarm unit,
A bushing tap adapter operated by DC power provided by the above DC rectifier circuit.
A bushing tap adapter which is connected to a bushing tap of a power facility and has a protection element for grounding a circuit in the event of an overvoltage fault, a field alarm unit for notifying a field worker of the operation of the protection element, and a server alarm unit for notifying an operator server below for diagnosing the bushing of the operation of the protection element;
A bushing diagnostic device connected to the above bushing tap adapter for measuring and diagnosing the electrical characteristics of the above bushing tap; and
An operator server that diagnoses the bushing and the power equipment from electrical characteristic information transmitted from the bushing diagnostic device.
Including,
The above protection device is,
A main protection element that turns on in the event of an overvoltage fault; and
A monitoring protection device connected in parallel with the above main protection device and connected in series with the above field alarm unit or the above server alarm unit.
Including,
Between the above-mentioned monitoring unit protection device and the ground, a visual monitoring unit as the above-mentioned field alarm unit and an electrical monitoring unit as the above-mentioned server alarm unit are connected.
A bushing tap floating fault diagnosis system in which the above monitoring unit protection element performs a function to notify the user that tap floating has occurred by conducting the visual monitoring unit and the electrical monitoring unit.
In Article 7,
The above bushing tap adapter,
An adapter frame that can be connected to a bushing tap of a power equipment such as a transformer;
A bushing tab connection located at one end of the above adapter frame and mechanically connected to the above bushing tab;
A cable connection portion located at the other end of the above adapter frame, to which a cable that mediates the above bushing diagnostic device is connected so that data communication with an external bushing diagnostic device is possible.
A bushing tab floating fault diagnosis system further equipped with.
delete In Article 7,
The above on-site alarm unit,
An LED that emits light when the turn-on current of the above-mentioned monitoring unit protection element is conducted; and
Snubber resistor to adjust voltage distribution to the above LED
A bushing tab floating fault diagnosis system including:
In Article 10,
The above server alarm section,
A relay contact in which the turn-on current of the above-mentioned monitoring unit protection element operates the contact through the winding inside the relay contact to generate a digital contact signal.
A bushing tab floating fault diagnosis system including:
In Article 7,
A DC rectifier circuit connected to both ends of the above protection element and generating DC power when the above protection element is turned on.
Including more,
The above on-site alarm unit,
A bushing tap floating fault diagnosis system operated by DC power provided by the above DC rectifier circuit.