JPS5836095Y2 - Multilayer concentric power cable - Google Patents

Description

[Detailed description of the invention] The present invention relates to a so-called multilayer concentric cable in which conductors constituting each phase of a multiphase multiwire line are arranged concentrically and insulated from each other. be.

For example, a three-layer concentric cable is constructed by arranging the conductors constituting the so-called R, S, and T phases of a three-phase three-wire line concentrically and insulated from each other. The impedance is significantly lower than that of a three-core twisted type electrical cable, which is constructed by twisting individual single-core electrical cables, so it is especially suitable for lines that require low impedance and low voltage drop. It is extremely advantageous for various purposes, and demand for it is expected to grow steadily in the future.

On the other hand, in power cables, the conductor is often formed into a hollow cylindrical shape in consideration of the skin effect.

In the above-mentioned multilayer concentric electric cable, the innermost conductor is often formed into a hollow cylindrical shape like the other conductors, and an arbitrary plastic string or the like is provided inside the conductor. In this case, the inside of the innermost conductor becomes a completely useless part.

The present invention was created in view of the above points, and
The present invention provides a useful multilayer concentric electrical cable by skillfully utilizing the inside of the innermost conductor in the multilayer concentric electrical cable.

The gist of this is that the stranded conductors constituting each phase of a multi-phase multi-wire line are arranged concentrically and insulated from each other, and that The main feature is that arbitrary control and communication lines are embedded inside the twisted wire conductor constituting the innermost layer.

Note that the stranded wire conductor constituting the innermost layer, which exhibits a high potential difference to the outside, has no potential difference within itself, and therefore, even if control and communication lines are internalized within this stranded wire conductor, the cable's electricity will be reduced. There is no need to worry about any loss of characteristics.

Moreover, since the control/communication lines are placed in the middle inner layer conductor of each layer, they can escape from the influence of electromagnetic flux generated when electricity is applied around the conductors of each layer, and are not subject to induction interference.

An embodiment of the present invention will now be described with reference to the accompanying drawings, in which 1, 2, 3 are arranged concentrically and mutually with predetermined first, second and third plastic insulation layers 4, respectively. ,5
．． The first, second and third stranded conductors are arranged through the conductors 6 and 6.

Incidentally, when the cable is energized, the first stranded conductor 1 constitutes the R phase, the second stranded conductor 2 constitutes the S phase, and the third stranded conductor 3 constitutes the T phase.

Reference numeral 7 denotes a control/communication line housed inside the first stranded conductor 1 via an arbitrary hollow pipe 8.

9 is a plastic protective layer constituting the outermost layer of the cable.

According to the multilayer concentric electrical cable of this embodiment constructed in this manner, it can be used simultaneously as a control/communication line, which is extremely convenient.

Moreover, the control and communication lines are arranged by housing the innermost stranded wire conductor, which has been left as a completely useless part in this type of cable, in the internal space, so this is due to the original characteristics of the cable. There is no concern that the control/communication lines will be damaged, and the control/communication lines are not affected by the electromagnetic flux that occurs when the conductors in each layer are energized, and no induction disturbances occur.

As described above, the present invention provides a multi-layer concentric electrical cable that can be used simultaneously for control and communication by skillfully utilizing parts that have been completely neglected as wasted parts up until now. The value is extremely large.

[Brief explanation of the drawing]

The figure is an explanatory diagram of an embodiment of the multilayer concentric cable cable of the present invention. 1: First stranded conductor, 2: Second stranded conductor, 3: Third stranded conductor, 4: First insulating layer, 5: Second insulating layer, 6: Third insulating layer, 7: Control/communication Line, 8: Hollow pipe, 9: Protective layer.

Claims (1)

[Scope of utility model registration request] The stranded conductors constituting each phase of a multi-phase multi-wire line are arranged concentrically and insulated from each other, and inside the stranded conductor constituting the innermost layer of the stranded conductor. A multilayer concentric electrical cable characterized by incorporating arbitrary control and communication lines.