JPH0197122A - Ice and snow coating prevention type electric wire - Google Patents

Abstract

PURPOSE:To thaw ice effectively, by a method wherein a heater is attached to the heat absorbing section of a heat pipe, arranged lengthwisely on an electric wire, and the heater is connected to a current transformer for heating it while a switch, opened and closed automatically by weather condition, is provided. CONSTITUTION:Heat pipes 4 are wound lengthwisely around an electric wire 1. Heaters 3 are provided along the heat pipes 4 while the heaters 3 are connected to the output side of current transformers 2 provided on the electric wire 1. A switch 5, opened and closed automatically by a weather condition, is provided between the heater 3 and the current transformer. According to this method, the thawing of ice may be effected effectively by a simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an improvement in an ice-and-snow prevention electric wire that is configured to actively prevent ice and snow from forming on the electric wire.

[Conventional technology and problems] Wire disconnection accidents and tower collapse accidents caused by ice and snow accretion on electric wires, as well as phase-to-phase short circuit accidents of electric wires caused by gear-ropping vibration caused by wing-shaped ice and snow accumulation. ,
Major accidents are reported every winter.

Therefore, in order to prevent such accidents, attempts have been made to attach rings to electric wires or form fin-like protrusions on the electric wires, and these efforts have been found to be effective to some extent. However, all of these methods use the weight of the ice and snow attached to the wires to create an imbalance in the gravity of the ice and snow themselves, thereby encouraging the ice and snow to fall from the wires. In some cases, the effects could not always be expected.

A surefire way to prevent ice and snow from accumulating on electric wires is to heat the wires to melt and fall the ice and snow. As a concrete example, twisting of heater wires has been proposed for a long time. However, trying to heat overhead power transmission lines using heater wires, for example, would require a huge amount of electricity, and this has not been achieved in the end. Another method for heating electric wires is to attach a magnetic material to the wire and use the hysteresis loss and eddy current loss that occur in the magnetic material when energized to generate heat in the wire. However, regardless of the principle, when experimenting with this, it is extremely difficult to make the magnetic material generate sufficient heat under low temperatures such as during snowfall, and the magnetic material must be installed at a narrow mounting pitch. It turned out that there were many gaps.

In recent years, the use of heat pipes as a new means of heating electric wires has attracted attention, and the applicant has already made a proposal.

A heat pipe is a pipe made of copper, stainless steel, aluminum, etc., in which a working liquid such as water, fluorocarbon, ammonia, or methanol compound is sealed, and the working liquid is heated at one end of the pipe, that is, at the heat absorption part. This gas is vaporized and condensed in the heat dissipation part of the pipe, which causes the pipe to generate heat by utilizing the heat dissipation.
This heat is used to heat the object to be heated, that is, the above-mentioned electric wire. The condensed working fluid is returned to the heat absorbing section using capillary action, and the above operation is repeated.

According to this heat pipe heating method, it is considered that the heat pipe is attached to the electric wire and thermal energy is applied to a localized heat absorption part of the heat pipe, so that it is relatively feasible. However, at present, electric wires are generally installed overhead above supporting structures such as steel towers, and thermal energy is transferred from above the support structure to the heat absorbing part of the heat pipe attached to such electric wires. It is not always easy to find a way to provide this. For this reason, even if we look at the actual proposals to date, only the application of the heating principle of heat pipes has been emphasized, and in reality, in such a hypothetical state, there is no concrete way to apply thermal energy to the heat absorption part of the heat pipe. In many cases, the question of what measures to take will be left unresolved.

[Summary of the Invention] The present invention has been made in view of the above-mentioned actual situation, and utilizes the current flowing through the electric wire itself as a heat source for providing thermal energy to the heat pipe, and uses a simple wire to connect the electric wire. By focusing on installing a current transformer and configuring the current transformer to be connected to a normal heater wire so that the heat absorption part of the heat pipe can be heated by the heater wire, an extremely reliable and efficient installation method has been developed. The present invention aims to provide an ice and snow-proof electric wire.

[Example] The present invention will be described below based on examples.

FIG. 1 is an explanatory diagram showing an example of the case where the present invention is applied to an overhead power transmission line as a specific example. Wire 1 to wire 1
A current transformer 2 is installed which generates a required voltage and current by applying current. A heater wire 3 is connected to the current transformer 2, and the heater wire 3 is wound around the electric wire 1. The heat absorbing portion 4a of the heat pipe 4 is attached to the heat absorbing portion 4a.

With the above configuration, the current transformer 2 is activated by the current flowing through the wire 1 to generate a required voltage, and the heater wire 3 is heated using the current transformer 2 as a power source. The heat absorbing portion 4a of the heat pipe 4 is heated. As a result, the heat radiation occurs in the heat pipe, the temperature of the entire heat pipe 4 rises, melting the ice and snow adhering to the electric wire 1, and preventing ice and snow from accumulating on the electric wire 1. in this way,
The method according to the present invention promotes heat generation of the entire heat pipe by heating a part of the heat pipe attached to the electric wire 1 using a simple device. Arrange the wires throughout the length of the wire,
Unlike the unrealistic configuration of heating the entire heater wire, this is a highly feasible solution, and at the same time, the power source for heating the heater wire can be solved simply and appropriately by installing a current transformer. The significance can be said to be worth mentioning.

In addition, in the present invention, the current transformer 2 operates as long as the electric wire 1 is energized, but the heater wire 3 that uses it as a power source does not need to be constantly heated, and is free from icing or build-up. Heating only needs to occur under weather conditions where snow occurs. For this purpose, as shown in FIG. 2, it is preferable to provide a switch 5 so that it can be turned on and off freely by, for example, wireless remote control.

As such an on/off operation means, an ice/snow detection sensor is used, and the sensor is configured to automatically turn on the switch in the event of ice/snow formation, so that the switch is automatically turned on depending on the weather conditions where the electric wire is placed.・If it is turned off, its efficiency will be greatly improved. Although not so sophisticated, various means can be considered for such an automatic on/off mechanism, such as on/off using bimetal or shape memory alloy.

As another configuration of the above-mentioned switch mechanism, as shown in FIG. It is also possible to provide a configuration in which a desired voltage can be supplied beyond the point.

Furthermore, regarding the heat pipe 4, the first and second
Of course, instead of being wound around the electric wire 1 as shown in the figure, it may be twisted together with the strands 1a and la constituting the electric wire 1, as shown in FIG.

[Effects of the Invention] As detailed above, by using the electric wire according to the present invention, the following excellent effects can be expected.

(1) Using a heat pipe as a heat source to melt the swimsuit,
Moreover, by arranging a heater in the heat absorbing portion, the amount of heat dissipated from the heat pipe can be greatly increased.

(2) Since a current transformer is used as the power source for the heater, the power supply configuration can be extremely simplified, and by selecting the configuration of the magnetic material, even when the current flowing through the wire is small,
It is possible to accurately extract the voltage necessary for heating.

(3) By employing a switch mechanism, operation can be suppressed under weather conditions where icing and snow do not occur, and unnecessary losses can be prevented.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing - of an embodiment of the electric wire according to the present invention,
FIG. 2 is an explanatory diagram showing another embodiment, FIG. 3 is an explanatory sectional view showing a modified example of the current transformer used in the present invention, and FIG. 4 is an explanatory sectional view showing a modified example of the heat pipe. It is. 1: Electric wire, 2: Current transformer, 3: Heater, 4: Heat pipe, 5: Switch. Agent Patent Attorney Fujio Sato

Claims (3)

[Claims] (1) Ice and snow prevention is achieved by arranging a heat pipe in the longitudinal direction of the electric wire, attaching a heater to the heat absorption part of the heat pipe, and connecting the heater to a current transformer that serves as a power source for heating the heat pipe. shaped wire. (2) The icing and snow prevention electric wire according to claim 1, wherein a switch is provided in the energizing circuit of the heater. (3) The ice-and-snow prevention electric wire according to claim 2, wherein the switch is configured to operate automatically depending on weather conditions.