JP2000092673A - Snow-melting device for iron tower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a snow-melting device for an iron tower that can surely prevent a flashover accident due to covering of the transmission line iron tower with snow without increasing the size of an insulator device. SOLUTION: An electrical heating element 7 is installed at the tip of an iron arm 2 of a transmission line iron tower. An overhead ground wire 5 is insulated and a CT 8 is installed, thus taking out an electromagnetic induction current flowing through the overhead ground wire 5. The secondary current of the CT 8 is rectified by a relay device 9 and is allowed to flow to the electrical heating element 7, and the tip part of the iron tower arm 2 is heated to prevent snow-sticking. The electrical heating element 7 can also be arranged at the mounting part of the CT for a short-circuiting display and that of a weather sensor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a snow melting apparatus for a power tower which is suitable for preventing a flashover accident caused by snow covering a power transmission tower in winter.

[0002]

2. Description of the Related Art When snow piles on an insulator string of a transmission line tower and a tower arm, when the snow partially melts, a current flows through the tower arm through the snow, which may cause a flashover accident. In particular, in the case of a multiple insulator series, the amount of snowfall tends to increase. Therefore, various measures have conventionally been taken to prevent snow covering on the insulator series.

[0003] For example, it has been devised that the amount of snow accretion is reduced by using a pair of insulators in a vertical direction as a pair of insulators. In addition, it has been devised to lengthen a connection fitting for connecting the insulator string and the tower arm to make it difficult to snow. However, depending on the weather conditions, it was not always possible to prevent snow cover on the insulator series even with these measures. In addition, there is a problem in that the method of increasing the interval between the insulator strings and the length of the connecting bracket leads to an increase in the size of the insulator device. In addition, if snow accumulates on the flash indicator CT or weather sensor installed on the tower arm, the normal function of these devices may be impaired.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and it is possible to reliably prevent a flashover accident caused by snowfall on a power transmission tower without increasing the size of an insulator device. The main object of the present invention is to provide a snow melting device for a steel tower. It is another object of the present invention to provide a snow melting apparatus for a tower that can prevent an obstacle caused by snow on a flash indicator CT or a weather sensor installed on a tower arm.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a power transmission tower having a tower arm,
A heating element for generating heat using an electromagnetically induced current flowing through an overhead ground wire of a transmission line tower is provided.

In the snow melting apparatus for a tower according to the present invention, an electromagnetic induction current flowing through an overhead ground wire is taken out by CT or the like, and is supplied to a heating element installed on the tower arm to heat the tip of the tower arm. However, even if it snows on the insulator series, it will not snow on the tower arm side. For this reason, a flashover accident in which a current flows through the tower arm through snow can be reliably prevented. Similarly, it is possible to prevent snow on the CT for the flash indicator and the weather sensor installed on the tower arm. Moreover, since the snow melting device for a tower according to the present invention does not require a low-voltage distribution line for a power supply, it can be installed on a transmission line tower in which a low-voltage distribution line is not laid, such as in a mountainous region, and an electromagnetic induction current flowing through an overhead ground wire. There is an advantage that the power consumption is small because the power consumption is reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall view of a power transmission tower provided with a snow melting device for a tower according to the present invention, wherein 1 is a tower main body, 2 is a tower arm, 3 is an insulator string attached to the tip of each tower arm 2, and 4 is Transmission lines 5 insulated and supported by the insulator string 3 are overhead ground wires at the upper end of the tower main body 1.
In this embodiment, one side of a pair of overhead ground wires 5 is insulated from the tower arm 2 by a small insulator 6.

As shown in FIG. 2, an appropriate number of heating elements 7 are installed at the insulator connecting portion at the tip of the tower arm 2. The heating element 7 may be of any type as long as it has a capability of generating infrared rays when energized. However, in consideration of being installed outdoors, it is preferable that the heating element 7 has excellent weather resistance and durability. Therefore, in this embodiment, a large number of ceramic mold type heating elements 7 in which resistance heating wires such as nichrome wires are embedded in the ceramic are used in series. Such a heating element 7 is sold by the present applicant under the trade name of Infrastein.

FIG. 3 is an explanatory diagram of a power supply system to these heating elements 7. As shown, overhead ground wire 5 on the insulated side
Is provided with CT8. Since the electromagnetically induced current always flows through the insulated ground wire 5 due to the alternating current flowing through the adjacent power line 4, when the CT 8 is installed around the CT, a secondary current flows through the CT 8. 9 is a relay device,
Rectifies secondary current. Also, as shown in FIG.
Is installed, it also has a function of synthesizing the secondary current of each CT8. The power output from the relay device 9 is voltage-controlled by the voltage control device 10 and then supplied to the heating element 7. If a sufficiently large induced current can be obtained, the CT 8 may be omitted and the voltage control device 10 may be directly connected from the overhead ground wire.

As shown in FIG. 1, the relay device 9 and the voltage control device 10 are arranged in the tower body 1. The CT 8 is arranged at a position close to the overhead ground wire 5 on one side, but the heating element 7 is arranged at the tip of each of the tower arms 2 on both sides.
1, each of these devices is connected.

In the snow melting apparatus for a steel tower according to the present invention thus constructed, the electromagnetic induction current flowing through the overhead ground wire 5 is taken out by the CT 8 and supplied to the heating element 7 to connect the insulator connecting portion at the tip end of the tower arm 2. Can be heated, so that even if snow falls on the insulator string 3 in winter, the snow melts on the tower arm 2 side, and the snow is covered so that it is connected between the tower arm 2 and the insulator string 3. There is no. In addition, due to the infrared rays radiated from the heating element 7, snow coverage of the insulator string 3 is reduced. Therefore, it is possible to reliably prevent a flashover accident in which current flows from the insulator string 3 to the tower arm 2 through the melted snow.

In another embodiment shown in FIG. 4, the heating element 7 is installed at the tip of the tower arm 2 at the mounting portion of the flash indicator CT 12. In addition, various weather sensors such as a wind direction sensor 13, a sunshine sensor 14, and a solar radiation sensor 15 may be installed in the tower arm 2. These devices can be protected from malfunction or stoppage due to snow.

The above-described snow melting apparatus for a steel tower according to the present invention utilizes the electromagnetic induction current flowing through the overhead ground wire 5, and therefore does not require a low-voltage power distribution line for a power supply. For this reason, it can also be installed in transmission line towers where low-voltage distribution lines are not laid, such as in mountainous areas. In addition, the snow melting apparatus for a steel tower according to the present invention has a transmission line 4
Instead of using the current flowing through the ground wire, the electromagnetic induction current flowing through the overhead ground wire 5 is used, so that there is an advantage that the power consumption is small. In summer, a switch built in the relay device 9 or the voltage control device 10 may be turned off to reduce power consumption.

[0014]

As described above, the snow melting apparatus for a steel tower according to the present invention does not require the insulator apparatus to be large in size as in the prior art, and consumes less power and causes a flashover accident caused by snow covering the power transmission tower. In addition, there is an advantage that malfunction of a device such as a weather sensor can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is an overall view of a power transmission tower provided with a snow melting device for a tower according to the present invention.

FIG. 2 is an enlarged view of a tip of a tower arm.

FIG. 3 is a diagram of a power supply system to a heating element.

FIG. 4 is an enlarged view of a distal end portion of a tower arm according to another embodiment.

[Explanation of symbols]

1 Tower body, 2 Tower arm, 3 insulators, 4 Transmission line, 5 Overhead ground wire, 6 Small insulator, 7 Heating element, 8 C
T, 9 relay device, 10 voltage control device, 11 cable, 12 CT for flash indicator, 13 wind direction and wind speed sensor,
14 sunshine sensor, 15 sunshine sensor

Claims (5)

[Claims] 1. A snow melting apparatus for a power tower, wherein a heating element that generates heat using an electromagnetic induction current flowing through an overhead ground wire of the power transmission tower is disposed on a power tower arm of the power transmission tower. 2. The snow melting apparatus for a steel tower according to claim 1, wherein the heating element is ceramic-molded. 3. The snow melting apparatus for a steel tower according to claim 1, wherein the heating element is installed at an insulator connecting portion at a tip end of the steel tower arm. 4. The snow melting apparatus for a steel tower according to claim 1, wherein the heating element is installed at a CT mounting part for a flash indicator at a tip end of the tower arm. 5. The snow melting apparatus for a steel tower according to claim 1, wherein the heating element is installed in a weather sensor mounting portion of the steel tower arm.