KR20230091559A - Recessed underground distribution box and manhole system for power facilities - Google Patents

Abstract

The underground buried distribution box of the present invention includes a sealed waterproof body so that external moisture does not flow into the inside; It is provided inside the waterproof body, one end is connected to the line from the underground transformer, the other end is connected to the load-side line, and the input / open state of each blocking element is visually observed to the outside of the waterproof body Reclosing protection device; and a moisture removal/display device provided inside the waterproof body to remove moisture inside the waterproof body and to visually indicate a moisture level inside the waterproof body to the outside of the waterproof body.

Description

Manhole system for buried distribution boxes and power facilities {RECESSED UNDERGROUND DISTRIBUTION BOX AND MANHOLE SYSTEM FOR POWER FACILITIES}

In particular, the present invention relates to a subterranean distribution box that can solve the space problem caused by installing a ground distribution box, reduce various construction costs, and improve stability by installing a distribution box near the secondary side of an SIDT.

In general, wires such as various electric lines or communication lines were commonly installed in the air using electric poles. However, in recent years, due to the problem of damaging the urban aesthetics due to the above electric poles and aerial wires, there is a trend of replacing or constructing new distribution lines in the form of underground burial.

1 is a photograph showing a ground transformer and a ground distribution box installed therewith.

In general, existing underground distribution line construction methods can be largely divided into direct burial type, conduit type, and electric power distribution type.

In both of these methods, manholes used for cables or cable ducts, intermediate connection points or lines where the lines are bent are buried underground, and transformers and switchgear are installed on the ground, and only at the point where these devices are installed, cables are pulled out to the ground and connected to the device. way to connect.

However, in constructing the underground distribution line as described above, the direct burial type and the duct type have a problem that goes against the purpose of the original underground distribution line due to devices for installing a transformer and a switch on the ground.

In other words, similar to the problems of supports for overhead distribution lines, space problems in construction (difficulty in installation due to civil complaints in the vicinity of private land), surrounding aesthetic impairment, safety risks (danger to pedestrians due to heat or explosion generated from equipment, and in case of rain) There are many problems such as the risk of electric shock) and the risk of collision with vehicles or pedestrians.

2 is a photograph showing the inside of a manhole in which an SIDT is installed as an underground buried transformer.

3 is a diagram showing a connection relationship between a SIDT and a ground distribution box in the prior art.

In Korea, underground transformers are buried in manholes in the form of buried underground solid insulated transformers (SIDTs) in areas where the problems according to the above-mentioned risk are serious. Recently, for safety reasons, the demand for SIDT installation by local governments is increasing, especially in housing districts and underground areas.

However, SIDT has a countermeasure against high humidity, so it can be buried in a manhole, but in the case of a distribution box, defects may occur at the contact point in a high humidity environment. there is.

On the other hand, the SIDT arrangement in the manhole and the structure of the ground distribution box take a long time to recover from the SIDT failure, and accordingly, rapid recovery measures are required.

In addition, when the distribution box is not installed, the secondary low voltage failure expands to a wide-area power outage, so although a ground distribution box is installed, there is a problem that the transformer cannot be protected in the event of a breakdown due to civil complaints due to ground installation and a long span between the transformer.

That is, although the SIDT was installed due to lack of space, the distribution box was installed again on the ground, causing the same complaints as the ground transformer, and the distance between the underground SIDT and the ground distribution box is long, making it difficult to protect the transformer in case of a fault within the section.

In addition, if only an underground transformer is used without installing a distribution box to resolve civil complaints, the secondary low voltage failure can expand to a wide-area power outage, and it is difficult to replace the current limiting fuse (FR CL Fuse) in case of a failure. This requires oblique replacement, but it is due to the difficulty in checking and replacing the fuse operation status due to the underground installation.

Republic of Korea Publication No. 10-2008-0043958 : Underground transformer

The present invention is to provide a distribution box that can be used by being buried underground together with a completely underground buried transformer.

An underground buried distribution box according to one aspect of the present invention includes a sealed waterproof body so that external moisture does not flow into the inside; It is provided inside the waterproof body, one end is connected to the line from the underground transformer, the other end is connected to the load-side line, and the input / open state of each blocking element is visually observed to the outside of the waterproof body Reclosing protection device; and a moisture removal/display device provided inside the waterproof body to remove moisture inside the waterproof body and to visually indicate a moisture level inside the waterproof body to the outside of the waterproof body.

Here, the reclosing protection device, an overcurrent protection circuit breaker for detecting an abnormal current and blocking the line from the underground transformer to the load side; an open/close switch for opening/closing a line from the underground transformer to the load side; And it may include a ground fault determination relay that detects a ground fault of a line from the underground transformer to the load side and operates the open/close switch.

Here, the ground fault determination relay may determine whether there is a ground fault based on measured values of the overcurrent protection circuit breaker line.

Here, the moisture removal/display device may include an electric dehumidifier that removes internal moisture using a heat pump method; and an internal water collection discharge device discharging the water collected by the electric dehumidifying device to the outside of the waterproof body. A humidity sensor for displaying a value obtained by measuring the humidity of the waterproof body to the outside of the waterproof body may be included.

Here, the moisture removal/display device may be a moisture absorbing device having a moisture absorbing agent as particles that can be visually observed from the outside of the distribution box and change color when moisture is absorbed.

A manhole system for power facilities according to another aspect of the present invention includes a buried transformer installed in the inner space of the manhole for arranging underground power facilities; and

A waterproof body sealed so that external moisture does not flow into the inside, and provided inside the waterproof body, a line from the transformer is connected to one end and a load-side line is connected to the other end, and each blocking element is closed/opened. A re-closing protection device visually observed outside the waterproof body, provided inside the waterproof body, removing moisture inside the waterproof body, and visually indicating the degree of moisture inside the waterproof body to the outside of the waterproof body A subterranean distribution box including a moisture removal/display device may be included.

Here, a plurality of lines are re-branched at the output terminal of the transformer, and the subterranean distribution box may be connected to each of the re-branched lines one by one.

If the underground buried distribution box according to the spirit of the present invention having the above configuration is implemented, there is an advantage that it can be used by being buried underground together with an underground buried transformer.

The underground buried distribution box of the present invention has the advantage of being able to prevent disputes over ground distribution box installation, in particular, the problem of private land occupancy or civil complaints.

The underground buried distribution box of the present invention has the advantage of solving the space problem caused by installing the ground distribution box in a narrow section and reducing the construction cost. More specifically, it is possible to drastically reduce unnecessary construction costs in the existing method of installing ground distribution box + new pipeline + new low voltage line.

1 is a photograph showing a ground transformer and a ground distribution box installed therewith.
2 is a photograph showing the inside of a manhole in which an SIDT is installed as an underground buried transformer.
Figure 3 is a diagram showing the connection relationship between the SIDT and the ground distribution box of the prior art.
Figure 4 is a block diagram showing an embodiment of an underground buried distribution box according to the spirit of the present invention.
Figure 5 is a conceptual diagram showing the operation principle of the reclosing of the underground buried type distribution box according to the spirit of the present invention.
6 is a conceptual diagram showing an embodiment of a reclosing type protection device that may be provided in an underground buried type distribution box according to the spirit of the present invention.
7 is a plan view showing an embodiment of an external window of a buried underground distribution box according to the spirit of the present invention.
8 is a schematic diagram showing the configuration of a manhole system for power facilities composed of an underground buried distribution box and an SIDT according to the spirit of the present invention.
9 is a photograph showing a transformer branch inside a manhole for connection of an underground buried distribution box according to the spirit of the present invention.

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

When a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it may be understood that another component may exist in the middle. .

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly dictates otherwise.

In this specification, the terms include or include are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features or numbers, It can be understood that the presence or addition of steps, operations, components, parts, or combinations thereof is not precluded.

In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description.

4 is a block diagram showing an embodiment of an underground buried type distribution box according to the spirit of the present invention.

The illustrated underground buried distribution box includes a sealed waterproof body 110 so that external moisture does not flow into the inside; It is provided inside the waterproof body, one end is connected to the line from the underground transformer, the other end is connected to the load-side line, and the input / open state of each blocking element is visually observed to the outside of the waterproof body Reclosing protection device; and a moisture removal/display device 180 provided inside the waterproof body to remove moisture inside the waterproof body and to visually indicate the level of moisture inside the waterproof body to the outside of the waterproof body.

The waterproof main body 110 is implemented in the form of a box made of a hard material such as metal, and a transparent window made of a material such as transparent acrylic is formed so that the input/open state of each blocking element and the moisture level can be visually seen from the outside. it is advantageous

The waterproof main body 110 includes eight line through-holes (each of three phases and a neutral line) through which the underground transformer-side lines and the load-side lines pass. It is preferable that the through-holes are also sealed to prevent moisture from entering. .

The reclosing protection device is a device that detects an overcurrent or ground/short circuit as an accident in a line connected to the distribution box, prevents an accident by blocking the line, and automatically recloses when the accident situation is released. A device performing such an operation may be configured by applying various technologies known in the power field.

For this purpose, as a main characteristic of the reclose protection device, when a certain current (minimum short-circuit current) or more flows in the secondary side line of the transformer, reclose is performed once, and in case of failure, it is opened (opened before current limiting fuse operation). In addition, it is desirable to be able to identify whether the protection device is operating (successfully) from the outside of the distribution box.

For example, as shown, the reclosing protection device includes an overcurrent protection circuit breaker 142 that detects an abnormal current and cuts off a line from the underground transformer to the load side; an open/close switch 144 for opening/closing a line from the underground transformer to the load side; and a ground fault determination relay 146 for operating the open/close switch 144 by detecting a ground fault in a line from the underground transformer to the load side.

5 is a conceptual diagram showing the operating principle of a reclosing furnace of a buried underground distribution box according to the spirit of the present invention.

The reclosing protection device having the structure shown in FIG. 4 may perform a reclosing operation according to the procedure of the conceptual diagram of FIG. 5 .

The ground fault determination relay 146 shown determines whether there is a ground fault from the measured values of the line of the overcurrent protection circuit breaker 142, and for this purpose, the voltage value of the line of the overcurrent protection circuit breaker 142 is directly received and measured , the current value is received from the CTs installed on the line of the overcurrent protection circuit breaker 142.

The illustrated ground fault determination relay 146 may be implemented as an OCGR that operates by detecting a ground fault current by zero-phase current at the time of a ground fault and opening a circuit breaker to cut off a line.

The illustrated ground fault determination relay 146 turns off the opening/closing switch 144 in a ground fault condition according to the ground fault determination result, and turns on the opening/closing switch 144 when the ground fault condition is released.

6 is a conceptual diagram showing an embodiment of a reclosing protection device that may be provided in an underground buried type distribution box according to the spirit of the present invention.

The illustrated type of reclosing protection device applies a product in which a built-in CT, an action identification rod, and an action relay are integrated in the form of a rod-type switch. In the case of an underground buried type distribution box to which the reclosing protection device shown in FIG. 6 is applied, the manufacturing cost can be further reduced. However, a transparent window should be formed in the waterproof body so that the reclosing operation can be confirmed with the operation identification rod from the outside of the distribution box.

The moisture removal/display device 180 may be implemented in a manner according to the scale of the buried underground distribution box. For example, in the case of a large-scale distribution box, it is implemented as a device that actively removes moisture using electrical energy, and in the case of a small-scale distribution box, a device that removes moisture using an absorbent such as silica gel in a manner similar to a hygroscopic respirator. can be implemented with

In the former case, the moisture removal/display device 180 may include an electric dehumidifier that removes internal moisture using a heat pump method; an internal water collection discharge device for discharging the collected water obtained by the electric dehumidifying device to the outside of the waterproof body; and a humidity sensor displaying a value obtained by measuring the humidity of the waterproof body to the outside of the waterproof body. Here, the electric dehumidifying device may be a compression driven dehumidifying device using a refrigerant or a dehumidifying device using a Peltier element.

In the latter case, the moisture removal/display device 180 can be visually observed from the outside of the distribution box and may include a moisture absorbing device including silica gel particles mixed with cobalt chloride or the like and a moisture absorbing agent so that the color changes when moisture is absorbed. .

In the latter case, the moisture absorbing device having a moisture absorbent of silica gel particles can simultaneously perform a role of removing moisture inside the distribution box and a role of displaying the degree of internal humidity by changing the color of the moisture absorbent that has absorbed some moisture.

7 is a plan view showing an embodiment of an external window for a buried underground distribution box according to the spirit of the present invention.

The underground buried distribution box in the case of FIG. 7 does not use a transparent window, but uses a separate LED display device provided outside to visually indicate the input/open state of each blocking element and the moisture level inside the waterproof body. It is expressed outside the distribution box.

Next, a manhole system for buried underground power facilities consisting of a buried distribution box and a buried transformer of FIG. 4 will be described.

8 is a schematic diagram showing the configuration of a manhole system for power facilities composed of an underground buried distribution box and an SIDT according to the spirit of the present invention.

9 is a photograph showing a transformer branch inside a manhole for connection of an underground buried distribution box according to the spirit of the present invention.

The manhole system for power facilities includes a buried transformer installed in the inner space of the manhole for arranging underground power facilities; and a waterproof body sealed to prevent external moisture from entering the inside, provided inside the waterproof body, one end connected to a line from the transformer, the other end connected to a load-side line, and closing/opening of each blocking element. A re-closing protection device whose state is visually observed outside the waterproof body, provided inside the waterproof body, to remove moisture inside the waterproof body, and to visually measure the degree of moisture inside the waterproof body to the outside of the waterproof body. It may include an underground buried type distribution box including a moisture removal/indicating device.

Due to the characteristics of the high-humidity environment inside the manhole, the underground buried distribution box is proposed as a closed configuration, and accordingly, it is difficult to add distribution lines as a general distribution box. Accordingly, in the manhole system for power facilities, it is advantageous to implement a structure in which a buried distribution box is in charge of only one distribution line, and a plurality of lines are re-branched from the transformer branch shown in FIG. 9 as an output terminal of the transformer. do. In this case, each of the re-branched lines is connected to the underground buried distribution box one by one.

This reflects the advantage in work convenience and scalability that it is easier to seal (seal) the branching structure, but the branching structure is not vulnerable to a humid environment, so it is placed outside the waterproof body of the underground distribution box. .

The above-mentioned manhole system for buried underground power facilities has a structure in which a dedicated distribution box is installed in the manhole on the secondary side of the SIDT, and the distribution box is installed in the short distance on the secondary side of the SIDT to solve the space problem caused by the installation of the distribution box on the ground and reduce various construction costs and can improve stability.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

In the detailed description of the present invention described above, a method for protecting power facilities has been exemplified, but the spirit of the present invention can also be applied to other facilities such as civil structures installed outdoors where forest fires can reach, and this is also the right of the present invention. Of course, it belongs to the range.

110: waterproof body
142: overcurrent protection breaker
144: open/close switch
146: ground fault determination relay
180: moisture removal / display device

Claims (7)

A sealed waterproof body to prevent outside moisture from entering the inside;
It is provided inside the waterproof body, one end is connected to the line from the underground transformer, the other end is connected to the load-side line, and the input / open state of each blocking element is visually observed to the outside of the waterproof body Reclosing protection device; and
A moisture removal/display device provided inside the waterproof body to remove moisture inside the waterproof body and to visually indicate the degree of moisture inside the waterproof body to the outside of the waterproof body.
An underground buried type distribution box including a.
According to claim 1,
The reclosing protection device,
An overcurrent protection circuit breaker that senses an abnormal current and cuts off a line from the underground transformer to the load side;
an open/close switch for opening/closing a line from the underground transformer to the load side; and
A ground fault determination relay that detects a ground fault in a line from the underground transformer to the load side and operates the open/close switch.
An underground buried type distribution box including a.
According to claim 2,
The ground fault determination relay,
A buried distribution box that determines whether there is a ground fault from the measured values of the overcurrent protection circuit breaker line.
According to claim 1,
The moisture removal / display device,
An electric dehumidifier that removes internal moisture using a heat pump method; and
an internal water collection discharge device for discharging the collected water obtained by the electric dehumidifying device to the outside of the waterproof body;
Humidity sensor for displaying the measured humidity of the waterproof body to the outside of the waterproof body
An underground buried type distribution box including a.
According to claim 1,
The moisture removal / display device,
An underground distribution box, which is a moisture absorption device that can be visually observed from the outside of the distribution box and has a moisture absorbent as particles that change color when moisture is absorbed.
A buried transformer installed in the inner space of a manhole for arranging underground power facilities; and
A sealed waterproof body to prevent external moisture from entering the inside;
It is provided inside the waterproof body, one end is connected to the line from the transformer, the other end is connected to the load-side line, and the closing / opening state of each blocking element is visually observed to the outside of the waterproof body Reclosing protection device ,
A subterranean distribution box including a moisture removal/display device provided inside the waterproof body to remove moisture inside the waterproof body and to visually indicate the degree of moisture inside the waterproof body to the outside of the waterproof body.
A manhole system for power facilities comprising a.
According to claim 6,
A plurality of lines are re-branched at the output end of the transformer,
A manhole system for power facilities in which each of the re-branched lines is connected to the buried distribution box one by one.

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