JP2007300744A - Flashover protective arrester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flashover protective arrester of a simple structure that can prevent a lightning from affecting general consumers who receives electric power jointly with a specific consumer. <P>SOLUTION: A lightning protection system is a device for protecting electric facilities of the general and specific consumers against a lightning damage targeting a joint receiving and distributing system with which the general and specific consumers can receive electric power jointly from lead-in distribution lines. The system includes flashover protective coils 41 of high impedance connected between the lead-in distribution lines 12 and electric facilities 44 inside the premises of the specific consumer 30, and connected in series to each lead-in distribution line 12 of each phase; a follow current prevention arrester 42 connected between each one end of these flashover protective coils 41; and a plurality of follow current prevention arresters 43 connected between the other ends of the flashover protective coils 41. The ground connection point of each follow current prevention arrester 43 is connected to a common equal potential ground pole 46 along with the ground terminal of the electric facilities 44, a steel tower 47, and a pulled-down conductor 49. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention, for example, when a lightning rod or a steel tower in a fixed radio base station as a specific consumer receives a direct lightning strike, the electric equipment of a general consumer connected to the same power distribution system as the base station premises or the base station The present invention relates to an anti-flashover device for protecting a human body from lightning damage (including communication equipment).

Conventionally, when a lightning strike occurs on a high-rise structure equipped with an antenna, lightning rod, or lightning rod, the equipment inside the structure is destroyed by a lightning surge that flows out through the low-voltage distribution line, or peripheral devices are connected via the low-voltage distribution line. An outflow lightning surge reduction circuit designed to prevent destruction is known from Patent Document 1.
This prior art includes a high voltage power supply transformer connected in series with a low voltage distribution line, and a high voltage lightning arrester such as a zinc oxide type lightning arrester connected between the transformer and the ground, and further, a low voltage as required. A lightning arrester, a fuse or the like is connected in series to the high-voltage lightning arrester.

Japanese Patent Laying-Open No. 2005-176554 (Claims 1, 2, 5-7, FIGS. 1, 5, 6, etc.)

  In the prior art according to Patent Document 1 described above, a high-voltage power transformer must be provided inside the structure, which increases the size and cost of the equipment and causes lightning to flow outside through the low-voltage distribution line. In some cases, the surge current is not sufficiently suppressed, and a spillover accident to general consumers connected to low-voltage distribution lines cannot be prevented.

  Accordingly, the problem to be solved by the present invention is to prevent the lightning damage from spreading to general consumers of the same distribution system jointly receiving power with a specific customer, and to easily protect various electric facilities from lightning damage. It is to provide a reverse flash prevention device.

In order to solve the above-mentioned problem, the anti-flashover device described in claim 1 is directed to a joint power distribution system in which a general customer and a specific customer can jointly receive power from the power distribution line. And anti-flashover device connected between the electrical equipment in the specific customer premises,
A high-impedance anti-flashing coil connected in series to each phase of the incoming distribution line, a continuity blocking lightning arrester connected between one end of these anti-flashing coils, and the anti-flashing coil A plurality of wake prevention arresters connected between the other ends of the
The case of the reverse flash arrester and the ground connection point between the plurality of continuity blocking arresters are common with the down conductor, the high-rise structure, and the electrical equipment connected to the lightning rod in the specific customer premises, etc. It is connected to the potential ground electrode.

According to the present invention, even if the lightning rod receives a direct lightning strike and the potential of the equipotential grounding pole rises, most of the voltage is borne by both ends of the reverse-flashing prevention coil having a large impedance via the continuity blocking lightning arrester. Therefore, the voltage applied to the lead-in distribution line becomes low, and the voltage and current flowing out to the general consumer side can be suppressed to protect the human body and electrical equipment from lightning damage.
Also, equipotential grounding for the case of a specific customer premises, including the case of the anti-flashover device, the ground connection point of the storm arrester, the electrical equipment, the tower base of the tower as a high-rise structure, and the down conductor. By connecting to the poles, the reference potential of each of these facilities can be made equal, and even if the ground potential increases during a lightning strike, there is no theoretical potential difference between each facility, Destruction can be prevented.
In addition, abnormal voltage due to induced lightning that has penetrated high-voltage distribution lines and lead-in distribution lines escapes to the equipotential grounding pole side via the reverse flash prevention coil and the continuity prevention lightning arrester, ensuring that the electrical equipment in the specific consumer is It is possible to protect.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, FIG. 1 is a block diagram showing an embodiment of the present invention. In FIG. 1, 10 is a high-voltage distribution line, 11 is a distribution transformer whose primary side is connected to the high-voltage distribution line 10, and 12 is a low-voltage lead-in distribution line connected to the secondary side of the distribution transformer 11. Note that one end of the secondary side of the distribution transformer 11 is grounded by a B-type ground electrode 13.

Here, the lead-in distribution line 12 is drawn into the specific consumer 30 side, and the specific consumer 30 is, for example, a fixed wireless base station.
Moreover, the lead-in distribution line 12 is drawn into the house 21 of the general consumer 20 from the secondary side of the distribution transformer 11, and the specific consumer 30 and the general consumer 20 constitute a joint power distribution system. ing.

In the specific customer 30, the anti-flashover device 40 according to the embodiment is connected to the incoming distribution line 12. The anti-flashing device 40 is connected between the anti-flashing coil 41 connected in series to a pair (each phase) of the lead-in distribution line 12 and between each end of the anti-flashing coil 41. The continuous current blocking lightning arrester 42 and two continuous current blocking lightning arresters 43 connected between the other ends of the reverse flash prevention coil 41 are configured.
Here, the reverse flash prevention coil 41 has a large impedance, and the continuity prevention lightning arresters 42 and 43 are constituted by connecting a lightning arrester and a reactor in series, for example.

  Electrical equipment (including communication equipment) 44 such as wireless equipment to which a DC power supply voltage is supplied is connected to both ends of the series circuit of the two continuous current blocking lightning arresters 43. An antenna 45 is connected to the electric tower 44 and attached to the steel tower 47.

A lightning rod 48 is installed at the top of the steel tower 47, and a down conductor 49 is connected to the lightning rod 48, and the down conductor 49 is installed along the steel tower 47.
Note that the housing of the reverse flash arrester 40, the ground connection point between the two continuous current blocking lightning arresters 43, the housing of the electrical equipment 44, the tower leg of the steel tower 47, and the down conductor 49 are collectively connected. It is connected to an equipotential ground electrode 46 as a house ground electrode.

Next, the operation of this embodiment will be described.
Now, when the lightning rod 48 or tower 47 receives a direct stroke, the lightning surge current I _s flows to equipotential ground electrode 46 via the tower foot portion of the down conductor 49 or tower 47. At this time, if the ground resistance of the equipotential ground electrode 46 is R _e , a ground potential rising voltage having a magnitude of I _s × R _e is generated.

  This voltage is applied to the B-type ground electrode 13 through the two secondary current blocking lightning arresters 43, the reverse flash prevention coil 41, and the secondary winding of the distribution transformer 11, but the secondary current blocking When the lightning arrester 43 is turned on, most of the ground potential rising voltage is borne by both ends of the reverse-flashing prevention coil 41 having a large impedance. Therefore, the voltage applied to the lead-in distribution line 12 side becomes low, and the general consumer 20 The voltage applied to the house 21 is also reduced. Therefore, the electric current which flows out to the general consumer 20 side also becomes small, and there is no possibility of harming the human body in the house 21 or destroying the electrical equipment.

Further, in the premises of the specific customer 30, the housing of the anti-flashing device 40, the ground connection point between the two continuation prevention lightning arresters 43, the housing of the electrical equipment 44, the tower legs of the steel tower 47, and the pull-down Since the conductors 49 are collectively connected to the equipotential ground electrode 46, each of these facilities is on the equipotential, and even if the ground potential rises during a lightning strike, it is theoretically between the facilities. Does not generate a potential difference, and can protect each equipment from overvoltage and overcurrent.
In addition, the continuity prevention lightning arrester 42 by the side of the distribution transformer 11 in the reverse flashing prevention device 40 is for protecting the reverse flashing prevention device 40 from the abnormal voltage which invades from the drawing-in distribution line 12 side.

  In addition, abnormal voltage due to induced lightning that has entered the high-voltage distribution line 10 and the lead-in distribution line 12 (including abnormal voltage due to mixed contact of distribution lines) is grounded equipotentially via the reverse flash prevention coil 41 and the continuity prevention lightning arrester 43. Since it escapes to the pole 46 side, the electrical equipment 44 in the specific consumer 30 can be reliably protected.

  As described above, in the present embodiment, by adding the anti-flashover device 40 to the premises of the specific customer 30, a spillover accident to the general customer 20 during a lightning strike is prevented, and at the same time, Various facilities can be protected, and the configuration of the anti-flashover device 40 is very simple, so there is no possibility of increasing the size of the device or increasing the cost.

FIG. 2 is a circuit diagram showing the anti-flashover device 40 connected to the lead-in distribution line 12 of the single-phase power distribution system, and is substantially the same configuration as FIG. In FIG. _{2, A 1, A 2,} A 3 is follow current blocking lightning _{arrestor, N 1,} N ₂ represents the reverse flashover prevention coil.
FIG. 3 is a circuit diagram when the present invention is applied to a three-phase power distribution system. 12A shows a three-phase lead-in distribution line, 40A shows a reverse flash prevention device, and 44A shows electric equipment. A _{4 to} A ₉ are continuation blocking lightning arresters, and N _{3 to} N ₅ are reverse flash prevention coils.
In the example of FIG. 3 as well, the reverse flashing prevention device 40A prevents the abnormal voltage and current accompanying the rise in the ground potential from flowing out to the general customer side as in FIGS. It is possible to prevent the electrical equipment from being destroyed.

It is a block diagram which shows embodiment of this invention. FIG. 2 is a circuit diagram of the anti-flashing device in FIG. 1. It is a circuit diagram of an anti-flashover device applied to a three-phase power distribution system.

Explanation of symbols

10: High-voltage distribution line 11: Distribution transformer 12, 12A: Lead-in distribution line 13: Type B ground electrode 20: General customer 21: House 30: Specific customer 40, 40A: Reverse flash prevention device 41: Reverse flash Prevention coil 42, 43: Continuity prevention lightning arrester 44, 44A: Electrical equipment 45: Antenna 46: Equipotential grounding electrode 47: Steel tower 48: Lightning rod 49: Pull-down conductor

Claims (1)

For a common power distribution system that can be received jointly by a general customer and a specific customer from a service distribution line, a reverse flash prevention device connected between the service distribution line and the electrical equipment in the specific customer premises In
A high-impedance anti-flashing coil connected in series to each phase of the incoming distribution line, a continuity blocking lightning arrester connected between one end of these anti-flashing coils, and the anti-flashing coil A plurality of wake prevention arresters connected between the other ends of the
The case of the reverse flash arrester and the ground connection point between the plurality of continuity blocking arresters are common with the down conductor, the high-rise structure, and the electrical equipment connected to the lightning rod in the specific customer premises, etc. An anti-flashing device characterized by being connected to a potential ground electrode.

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