JPH07296646A - Power cable built in with optical fiber wire temperature sensor and conductor temperature measuring method for power cable - Google Patents

Abstract

PURPOSE:To accurately measure a conductor temperature with no correction by the temperature required by storing an optical fiber wire temperature sensor in a metal tube twisted to be mixed and built in the inside of a twisted wire conductor. CONSTITUTION:In a power cable, an optical fiber temperature sensor 13' is mixed to be twisted and built in a segment conductor 3' with a twisted element wire 3a constituting partly this segment conductor 3'. Since heat is directly transmitted to the optical fiber temperature sensor 13' from the segment conductor 3', a temperature of the conductor 3' can be directly measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power cable such as an OF cable and a CV cable, and more particularly to a power cable having a built-in optical fiber line temperature sensor and a method for measuring a conductor temperature of the power cable.

[0002]

2. Description of the Related Art A conductor of a power cable generates heat due to resistance of the conductor when electricity is applied. On the other hand, oil-impregnated paper or cross-linked polyethylene used as an insulating material cannot be easily heated to a high temperature, and the allowable temperature is determined according to the material. In general use, it is limited by the maximum allowable current calculated in advance, and the actual conductor temperature cannot be known. If the temperature of the conductor can be known directly, it is extremely effective in operation. Therefore, an optical fiber temperature sensor has been developed. Conventionally, to incorporate such an optical fiber temperature sensor, as shown in FIG. 2, the optical fiber temperature sensor was inserted into the oil passage 1 in the conductor of the single-core OF cable. Note that FIG.
The single-core OF cable in is a 220kV 1x2500 scare millivinyl-corrosion aluminum-covered OF cable.
Is spiral steel pipe, 3 is segment conductor, 4 is segment conductor insulating paper, 5 is binder, 6 is carbon paper on conductor,
7 is oil-impregnated insulating paper, 8 is carbon paper on insulating paper, 9 is a shielding layer, 10 is copper wire woven cloth tape, 11 is corrugated aluminum cover, 12 is vinyl anticorrosion layer, and 13 is optical fiber temperature sensor. , 13a are metal tubes such as stainless steel tubes, and 13b is an optical fiber.

[0003]

The optical fiber temperature sensor can detect the temperature linearly over several kilometers, for example, every 1 m. However, the temperature obtained thereby is the temperature of the optical fiber line itself, even if it gets tired. In a steady state (a constant current is flowing and there is no change in ambient temperature), the oil in the conductor oil passage and the optical fiber line are at the same temperature, and as a result, the conductor temperature is being measured. Generally, the conductor temperature changes momentarily due to load fluctuations. Since the temperature change is conducted using oil as a medium, the temperature itself of the optical fiber wire is different from the conductor temperature, and an accurate conductor temperature cannot be known. In the prior art, the complicated work of correcting the temperature difference as described above by calculation is required.

Therefore, an object of the present invention is to provide a power cable with a built-in optical fiber line temperature sensor and a power cable that can know an accurate conductor temperature without the need for the above-described calculation correction for the temperature difference. It is to provide a conductor temperature measuring method.

[0005]

The power cable with a built-in optical fiber line temperature sensor provided by the present invention is such that the optical fiber line temperature sensor housed in a metal tube is mixed and twisted inside a stranded conductor, The heat conduction from the conductor to the optical fiber temperature sensor is directly performed.

Also, The conductor temperature measuring method of the power cable provided by the present invention directly measures the temperature of the conductor by mixing and twisting the optical fiber wire temperature sensor housed in the metal tube into the stranded conductor of the power cable. It was done like this.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of an electric power cable with a built-in optical fiber temperature sensor according to the present invention. The power cable of this embodiment is a 220 kV 1 × 2500 scare millivinyl-corrosion-aluminum-protected OF cable, and the same parts as those in FIG. 2 are denoted by the same reference numerals as those in FIG. I want to be done.

However, in the power cable of this embodiment,
The optical fiber temperature sensor 13 'is formed by mixing and twisting a part 3'of the segment conductor together with the twisted strands 3a constituting the segment conductor 3', and incorporating it in the segment conductor 3 '.

Thus, the optical fiber temperature sensor 1
Since 3'is directly embedded in the segment conductor 3 ',
From the segment conductor 3'to the optical fiber temperature sensor 13 '
Therefore, heat is directly transmitted to the conductor, so that the temperature of the conductor can be directly measured by the optical fiber temperature sensor 13 '.

[0010]

According to the power cable with a built-in optical fiber temperature sensor and the method for measuring the conductor temperature of the power cable according to the present invention as described above, the optical fiber temperature sensor is built in so as to be in direct contact with the twisted strands of the conductor. Therefore, the temperature of the conductor can be directly measured by the optical fiber temperature sensor, and the accurate conductor temperature can be measured, and thus, the one that does not require the calculation correction for the temperature difference which was required in the past. The obtained and practical effect is great.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing an embodiment of a power cable with a built-in optical fiber wire temperature sensor according to the present invention.

FIG. 2 is a cross-sectional explanatory view showing an example of a conventional power cable with a built-in optical fiber temperature sensor.

[Explanation of symbols]

 3'segment conductor 3a twisted strands 13 'optical fiber temperature sensor 13a metal tube (stainless tube) 13b optical fiber

Claims (2)

[Claims] 1. An electric power cable with a built-in optical fiber line temperature sensor, characterized in that the optical fiber line temperature sensor housed in a metal tube is mixed and twisted inside a stranded wire conductor of the electric power cable. 2. The conductor of a power cable, wherein the temperature of the conductor is directly measured by mixing and incorporating an optical fiber wire temperature sensor housed in a metal tube inside the stranded conductor of the power cable. How to measure temperature.