KR102332571B1 - An electric power supply method of the control unit for pad mounted type switchgear for underground line - Google Patents

Abstract

The present invention supplies the power of the control unit for controlling the ground switch and circuit breaker by using a low voltage on the secondary side of the transformer or the voltage transformer of the ground switch and circuit breaker installed close to the installed ground switch and circuit breaker rather than the voltage transformer. The voltage transformer is no longer required, so it is possible to solve the electrical safety accident caused by the failure of the voltage transformer, as well as the problem of electric line blackout due to the failure due to the poor quality of the voltage transformer, and the installation of the voltage transformer It can solve the economic burden caused by the cost of replacement and replacement, and since the voltage transformer is not installed, the height of the ground switch and circuit breaker can be minimized. Disclosed is a power supply method for operating a control circuit of a switchgear and a circuit breaker.

Description

An electric power supply method of the control unit for pad mounted type switchgear for underground line

The present invention relates to a power supply method for operating a control circuit of a ground switchgear and a circuit breaker, and more particularly, to a control circuit operation of a ground switch and a circuit breaker in which the operating power of the control unit of the ground switch is supplied using the power of a transformer. It relates to a power supply method.

In general, ground-mounted switchgear and circuit breaker (hereinafter referred to as ground equipment) are electrical equipment installed on the ground in an underground distribution line and used for branching or dividing lines.

In other words, the power supplied from the substation to the consumer is normally supplied at an extra-high voltage of 22,900V. For operation, a ground device (Pad SW) that can control the power supply is installed on the ground or outdoors near the sidewalk.

On the other hand, ground equipment can be divided into a manual type by manpower and an automatic type by controlling in the opening and closing operation of the line. A terminal device (RTU) and a communication device are additionally provided to enable remote control of the battery and opening/closing.

1 shows an example of a conventional automatic ground device, as shown, a control unit 2, a distribution automation terminal (FRTU) 3, and a storage battery 4 are installed on one side of the ground device 1, and A built-in fuse voltage transformer (PT) 5 is installed on the other side.

In addition, a voltage transformer-side bushing 6 is installed in the ground device 1, and an elbow cable 7 is connected between the voltage transformer-side bushing 6 and a built-in fuse voltage transformer 5 to provide a built-in fuse voltage. An extra-high voltage power supply is applied to the primary side of the transformation device (5).

As such, the extra-high voltage power (13200V) applied to the primary side of the built-in fuse voltage converter 5 is converted to 220V by the built-in fuse voltage converter 5, so that it is used for controlling ground equipment. ) is transmitted to the control unit 2, and the rectification and storage batteries are charged there, so that the control circuit of the control unit 2 is operated.

Accordingly, in the conventional ground equipment, a voltage transformer (PT) must be installed to transform the primary applied special high voltage to a low voltage to supply power to the control unit, so a space occupied by the voltage transformer is required. As the height (h1) of the device has to be manufactured and installed high, there is a problem in that it adversely affects the aesthetics of the city, as well as restricts the view right of the shops in the surrounding shopping mall where the ground device is installed.

In addition, there is a problem in that a failure occurs frequently due to a poor quality of the voltage transformer, and thus a sudden power outage occurs in an electric line.

Accordingly, when the voltage transformer installed on the ground equipment is defective, it is replaced or the ground equipment itself is replaced, but the cost of replacing the voltage transformer or the ground equipment is aggravated, causing economic inefficiency.

In addition, there is a problem that not only causes an increase in the manufacturing cost due to the installation of the voltage transformer on the ground equipment, but also the cost increases as the cable is tested for each section of the ground equipment due to the voltage converter.

In order to solve this problem, various means for supplying power to the control unit of the ground equipment have been devised.

Looking at the prior art, a control power supply device for a load switchgear has been devised, which is Patent Registration No. 10-0186352, which consists of an insulated elbow connected to a regular power bushing, an insulated fuse pipe connected to the insulated elbow and a cable, and the insulated fuse pipe. It consists of a power transformer coupled to the end, an insulating cap interposed between the insulating fuse tube and the power transformer so that the conductive part is not exposed, a rectifier connected to the power transformer with a cable, and a battery connected to the rectifier to supply electricity, In the active state of the switchgear, the constant power is used, and in the event of a power outage, the battery charged by the constant power is used so that the automatic operation power can be always supplied. to completely rule out the possibility of

However, since the conventional technology also has a transformer, a rectifier and a battery installed inside the switchgear, the above-mentioned problems are still not solved.

Patent Document 1: Republic of Korea Patent No. 10-0186352 (Registered on Dec. 29, 1998) Patent Document 2: Republic of Korea Patent Publication No. 10-2019-0005536 (published on January 16, 2019)

The present invention does not have a voltage transformer (PT) inside the ground switch and circuit breaker, but receives the low voltage (220 V) of the transformer already installed around the ground switch and circuit breaker, and supplies the necessary power to the control side of the ground switch and circuit breaker An object of the present invention is to provide a power supply method for the operation of the control circuit of the ground switch and circuit breaker to minimize the height of the ground switch and circuit breaker and to solve the problems caused by the provision of the voltage transformer.

As a means for achieving the above object, the present invention provides a method for supplying power for a control circuit operation of a ground switch and circuit breaker, after disconnecting the low voltage cable from the voltage transformer (PT) receptacle installed in the ground switch and circuit breaker, the power cable is separated. A first step of separating the voltage transformer power supply by covering the power supply protection cap on the receptacle; a second step of removing the low-voltage cable between the control unit from the secondary side of the voltage transformer and insulating the complex from which the low-voltage cable was removed from the control unit to separate the low-voltage cable on the secondary side of the voltage transformer; a third step of constructing a power connection cable and a flame-retardant inner tube to the control unit of the ground switch and circuit breaker in which the low voltage power is separated from the voltage transformer; a fourth process of constructing a power protector so as to be located on the control side of the ground switch and circuit breaker after the third process; a fifth step of connecting the alternative power source of the power protector constructed by the fourth step and the alternative power transformer, but connecting the alternative power source to the power protector through the underground pipe connecting the ground switchgear and the circuit breaker and the transformer; a sixth step of connecting the power protector, the ground switch and the circuit breaker to the control unit of the ground switch and circuit breaker in which the alternative power is connected after the fifth step with a low voltage cable for alternative power supply to the control unit; It is provided in the seventh process of turning on the power of the power protector switch, applying an alternative power to the control unit of the ground switch and circuit breaker, and checking whether there is an abnormal power supply to the control unit of the ground switch and circuit breaker.

Furthermore, in the first step, before disconnecting the voltage transformer power installed in the ground switchgear and the circuit breaker, an alternative power checking step of checking whether a ground transformer capable of alternative power is installed around the ground switch and the circuit breaker; Voltage transformer defect confirmation process for checking whether the voltage transformation equipment of the installed ground switch and circuit breaker is defective; A power polarity confirmation process for confirming the power polarity of the voltage conversion device for which the defect is confirmed is provided.

The present invention supplies the power of the control unit for controlling the ground switch and circuit breaker to the ground switch and circuit breaker by using the low voltage on the secondary side of the ground transformer or the voltage transformer of the ground switch installed close to the installed ground switch and circuit breaker, rather than the voltage transformer. Since the voltage transformer is not required, it is possible to solve the problem of electric safety accidents caused by the failure of the voltage transformer as well as the problem of line blackout due to the failure due to the poor quality of the voltage transformer, and the installation and replacement of the voltage transformer It can solve the economic burden caused by the cost, and since the voltage transformer is not installed, the height of the ground switch and circuit breaker can be minimized, so it can solve not only the aesthetics of the surrounding shopping mall but also the obstructing the view right.

1 is a conceptual diagram showing the configuration of a conventional ground switch and circuit breaker.
2 is a block diagram showing the ground switch and circuit breaker constructed by the power supply method for the operation of the control circuit of the ground switch and circuit breaker according to the present invention.
3 is a conceptual block diagram of a construction state of a power supply method for the operation of the control circuit of the ground switch and circuit breaker according to the present invention.
4 is a flowchart illustrating a process of a power supply method for operating a control circuit of a ground switch and circuit breaker according to the present invention.
5 is a process diagram of another embodiment of a power supply method for the operation of the control circuit of the ground switch and circuit breaker according to the present invention.

Hereinafter, in addition to the above objects, other objects and features of the present invention will become apparent through the description of the embodiments with reference to the accompanying drawings.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, a power supply method for operating a control circuit of a ground switch and a circuit breaker according to an embodiment of the present invention will be described with reference to the accompanying drawings.

As shown, the present invention is a first process (S1) of separating the voltage transformer (PT) low voltage power source, a second process (S2) of separating the secondary side cable of the voltage transformer (PT), and a third process of constructing a cable for an alternative power source Process (S3), the fourth process of constructing the power protector (S4), the fifth process of connecting an alternative power to the power protector (S5), the sixth process of electrically connecting the power protector with the ground switch and circuit breaker control unit (S6) ) and a seventh process (S7) of turning on the switch power of the power protector.

More specifically, in the first process (S1) of the present invention, after disconnecting the low voltage power cable from the voltage transformer (PT) receptacle installed in the ground switch and circuit breaker 10, the low voltage power cable is placed in the separated receptacle. This is the process of separating the voltage transformer power supply by covering the power supply protection cap.

That is, the power cable electrically connecting the voltage transformer (PT) previously installed in the ground switch and circuit breaker 10 and the control unit 11 of the ground switch and circuit breaker 10 is separated from the voltage transformer (PT) receptacle, and the receptacle Put a protective cap on

The second process (S2) of the present invention is a process of removing the low-voltage cable between the control unit from the secondary side of the voltage transformer and insulating the terminal from which the low-voltage cable is removed from the control unit to separate the low-voltage cable on the secondary side of the voltage transformer.

That is, the low voltage supply cable, which is the secondary side wire that electrically connects the ground switch and circuit breaker 10 and the previously installed voltage transformer, is removed and insulated, and the secondary side cable of the voltage transformer installed from the ground switch and circuit breaker 10 . separate

The third process (S3) of the present invention is a process of constructing a power connection cable and a flame-retardant inner tube to the ground switch and circuit breaker 10 from which the voltage transformer is separated.

That is, the ground switch and breaker 10 and the power connection cable of the alternative power transformer 30 close to the ground switch and breaker 10 through the underground pipe 31 connecting the breaker 10 and the alternative power transformer 30 The power connection cable connected to the ground switch and the circuit breaker 10 side by entering the circuit breaker 10 side and a flame-retardant cable, which is a flame-retardant inner tube, are constructed.

In this case, it is preferable to use an inner tube of about 16 mm or more for the flame-retardant inner tube.

The fourth process (S4) of the present invention is a process of constructing the power protector 20 so as to be located on the control unit 11 side of the ground switch and circuit breaker 10 after the third process (S3).

That is, the power protector 20 consisting of a circuit breaker or a watertight circuit breaker is placed on the control unit 11 side of the ground switch and circuit breaker 10 to be constructed inside the ground switch and circuit breaker 10, and at this time In order to prevent electric leakage due to a watertight circuit breaker, it is preferable to provide a power protector 20 as a watertight circuit breaker.

The fifth process (S5) of the present invention connects the alternative power of the power protector 20 and the alternative power transformer 30 constructed by the fourth process (S4), but the ground switch and circuit breaker 10 and the transformer 30 ) is a process of connecting an alternative power source to the power protector 20 through the underground pipe 31 connecting the.

That is, by electrically connecting the alternative power cable electrically connected to the alternative power transformer 30 to the power protector 20 located on the ground switch and circuit breaker 10 control unit 11 side, the alternative power of the alternative power transformer 30 It is applied to the power protector 20 through this alternative power cable.

At this time, if the underground pipe line 31 is not constructed between the ground switch and circuit breaker 10 and the alternative power transformer 30 , the underground pipe line 31 may be constructed first.

In the sixth process (S6) of the present invention, after the fifth process (S5), the power supply protector 20 to which the alternative power is connected and the ground switchgear and the circuit breaker 10 in which the secondary-side low voltage cable of the voltage transformer is separated is replaced with a power supply cable It is a process of connecting power to the power protector 20 and the control unit 11 of the ground switch and circuit breaker 10 by connecting to (12).

That is, the power protector 20 electrically connected to the alternative power transformer 30 and the control unit 11 of the ground switch and circuit breaker 10 are electrically connected to the alternative power supply cable 12 and applied to the power protector 20 . Alternative power to be applied to the control unit 11 of the ground switch and circuit breaker 10 through the supply cable (12).

At this time, it is natural to electrically connect to the control unit 11 of the ground switch and circuit breaker 10 by checking the power polarity of the alternative power source.

In the seventh process (S7) of the present invention, an alternative power is applied to the control unit 11 of the ground switch and breaker 10 by turning on the switch power of the power protector 20, and the ground switch and circuit breaker 10 It is a process of checking whether there is an abnormality in the control unit 11 power supply.

In addition, when the failure of the pre-installed voltage converter is prolonged, the storage battery electrically connected to the control unit 11 is prevented. If the storage battery is over-discharged, the discharged storage battery can be replaced with a new one.

In the present invention, when a new ground switch and circuit breaker not equipped with a voltage transformer is developed and installed, an alternative power source can be electrically connected to the ground switch and circuit breaker. As it can be manufactured to be lower than the height (h1) of the existing ground switchgear and circuit breaker installed, the height of the ground switch and circuit breaker can be minimized, thereby suppressing not only the aesthetics of the surrounding shopping mall but also obstructing the right to view.

In the first step (S1), before disconnecting the power of the voltage transformer installed in the ground switch and circuit breaker 10 in the first process (S1), an alternative to check whether a ground transformer capable of alternative power is installed around the ground switch and circuit breaker 10 Power supply confirmation process (S11), voltage transformer defect confirmation process (S12) for checking whether the voltage transformation device of the installed ground switch and circuit breaker 10 is defective A confirmation process (S13) is provided and made.

Accordingly, it is enough to check whether the voltage transformer (PT) of the ground switch and circuit breaker 10 already installed at the site capable of supplying alternative power is defective, and then separate the voltage transformer whose failure is confirmed and supply the alternative power.

In addition, in the first process (S1) of the present invention, in order to completely separate the voltage transformer from the ground switch and circuit breaker, the elbow cable is separated from the bushing on the voltage transformer side of the ground switch, and an insulating cap is installed on the bushing to protect the bushing. A step of electrically protecting the extra-high voltage charging part may be added.

division switch manufacturing cost Bad voltage transformer
(PT) replacement cost According to PT defect
Ground switch replacement cost reduced unit price 1 million won/unit 150 million won/unit 10 million won/unit Quantity (large) 15,000 units 200 cars 20's Estimated savings 1.5 billion won 300 million won 200 million won

[Table 1] shows the expected cost reduction effect when the ground switch and circuit breaker are manufactured and operated according to the present invention.

As shown in [Table 1], the manufacturing cost of the existing switchgear is about 2 billion won, the replacement cost of the voltage transformer (PT) is 500 million won due to the failure of the voltage transformer (PT), Direct cost savings of about 1.5 billion won per year, including 200 million won in costs, can be saved.

In addition, considering the cost caused by the power loss of the voltage transformer, the test and diagnosis cost of the extra-high voltage cable, and the social cost caused by the power outage caused by the faulty voltage transformer, it is possible to save 2 to 3 billion won per year. It is expected that unexpected power outages of electric lines will be prevented, as well as cost savings due to the operation of ground switchgear.

In addition, in the event of a failure of the voltage transformer installed in the existing ground switchgear and circuit breaker, the period for restoring the power supply of the control unit can be shortened from more than 14 days to less than 1 day. The height h2 of the switchgear and the circuit breaker 10 can be minimized.

As described above, the present invention has been described with specific matters such as specific components and limited embodiments and drawings, but these are provided to help a more general understanding of the present invention, and the present invention is not limited to the above embodiments. , various modifications and variations are possible from these descriptions by those of ordinary skill in the art to which the present invention pertains.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and not only the claims to be described later, but also all those with equivalent or equivalent modifications to the claims will be said to belong to the scope of the spirit of the present invention. .

10: ground switch and circuit breaker 11: control unit
12: alternative power supply cable 20: power protector
30: transformer 31: underground pipeline
S1: 1st process S2: 2nd process
S3: third process S4: fourth process
S5: 5th process S6: 6th process
S7: 7th process

Claims (3)

Separating the voltage transformer for which the defect has been confirmed, supply power to the ground switch and circuit breaker control unit for the operation of the control circuit of the ground switch and circuit breaker. The first step (S1) of separating the voltage transformer power supply by putting a power protection cap on the receptacle from which the power cable was disconnected after disconnecting the power cable (S1) Including the second step (S2) of separating the secondary side cable of the voltage transformer by insulating the side terminal, the third step of constructing the cable (S3), the fourth step of constructing the power protector 20 (S4) , After the fifth process (S5), the fifth process (S5) of connecting the alternative power to the power protector 20, the power protector 20 to which the alternative power is connected and the ground switch and the circuit breaker 10 in which the voltage transformer is separated The control unit 11 is connected with an alternative power supply cable 12 to connect the power of the power protector 20 and the ground switch and circuit breaker 10 in the sixth process (S6) and the power protector 20 switch power on ( The ground switch and In the power supply method for the control circuit operation of the breaker,
The third step (S3) is,
The power connection cable of the alternative power transformer 30 close to the ground switch and circuit breaker 10 is drawn into the ground switch and breaker 10 where the voltage transformer is separated, and the power connection cable connected to the ground switch and breaker 10 side, and Construction of flame-retardant inner pipe,
The fourth step (S4) is,
After the third process (S3), the power protector 20 is constructed to be located on the control unit 11 side of the ground switch and circuit breaker 10, but the power protector 20 is composed of a watertight circuit breaker to prevent leakage due to humidity. to construct,
The fifth step (S5) is,
The power protector 20 constructed by the fourth process (S4) and the alternative power of the alternative power transformer 30 introduced to the ground switch and circuit breaker 10 side by the third process (S3) are connected, but the ground switch and A method of supplying power for a control circuit operation of a ground switchgear and a circuit breaker, characterized in that the alternative power is connected to the power protector 20 through an underground pipe 31 connecting the breaker 10 and the transformer 30. According to claim 1,
Before disconnecting the voltage transformer power installed in the ground switch and circuit breaker 10 in the first process (S1),
Alternative power checking process (S11) of checking whether a ground transformer capable of alternative power is installed around the ground switch and circuit breaker (10);
a voltage transformation device failure checking step (S12) of checking whether the voltage transformation device of the installed ground switch and circuit breaker 10 is defective;
A power supply method for operating a control circuit of a ground switch and circuit breaker, characterized in that a power polarity checking step (S13) of confirming the power polarity of the voltage transformation device for which the defect is confirmed is provided.
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