CN203288346U - Middle-voltage variable-frequency power cable - Google Patents

Abstract

The utility model discloses a medium-voltage variable-frequency power cable, which comprises a cable core, and the cable core is formed of three main cores and three secondary cores alternately arranged and twisted; The insulation layer, the metal shielding layer and the non-woven fabric tape are wrapped around in turn from the inside to the outside, and the outer sheath is extruded on the outermost layer of the cable core. The main wire core is composed of the main wire conductor and the conductor shield, the main wire core insulation, the insulation shielding layer and the phase-separated copper tape shielding layer extruded sequentially outside the main wire conductor; the three auxiliary wire cores are composed of the auxiliary wire The conductor and the secondary line insulation layer extruded outside the secondary line conductor. The utility model adopts the double shielding effect of phase-separated shielding and all-inclusive shielding, which not only has a channel for short-circuit current or leakage current, but also has the function of shielding external signal interference, improves the shock resistance of voltage resistance of frequency conversion equipment, and prolongs the length of cables. service life.

Description

A medium voltage variable frequency power cable

technical field

The utility model relates to the field of wires and cables, in particular to a medium-voltage variable-frequency power cable.

Background technique

All aspects of equipment included in frequency conversion speed regulation technology, such as frequency conversion motors, frequency converters, etc., have reached a very high level at home and abroad. However, as the connection cable between the frequency conversion motor and the frequency converter, that is, the power supply cable for the frequency converter, the development level in our country is not high. At present, XLPE insulated metal shielded cables are widely used for inverter connection cables. This kind of cable can be used in ordinary occasions, but it can be used in some special occasions in industrial and mining enterprises, such as high temperature, oil pollution, long-term connection use, and electromagnetic compatibility. When used in demanding occasions, the following problems will occur: high-frequency electromagnetic waves interfere with surrounding precision electronic equipment and electrical measurement, detection and protection equipment. The frequency conversion motors used in steel mills, chemical plants and other industrial and mining enterprises have relatively large power, and the length of the cable connecting the frequency conversion motor and the frequency conversion power supply is relatively long. The cable is an effective carrier for high-frequency electromagnetic waves to be emitted outward during operation. The shielding layer of ordinary frequency conversion cables has not been specially set, so it cannot effectively shield electromagnetic waves, and will interfere with the surrounding precision electronic equipment and electrical measurement, detection and protection equipment, reduce its accuracy, and in severe cases, make adjustment and control impossible, and even cause damage. .

At present, frequency conversion power cables, as a type of power cable for transmitting electric energy, are mainly used in frequency conversion circuit equipment. Low-voltage frequency conversion cables are frequently used. In order to improve the voltage transmission level and meet the frequency conversion capabilities of high-frequency equipment, a kind of Main circuit power cables for medium voltage inverters.

Utility model content

The technical problem to be solved by the utility model is to provide a medium-voltage variable-frequency power cable that shields external signals, has high safety performance, prevents external electromagnetic signal interference, and has a long service life.

A medium-voltage variable-frequency power cable described in the utility model includes a cable core, and the cable core is formed by arranging and twisting several main cores and several auxiliary cores; The outside of the core is wrapped in turn from the inside to the outside with an isolation layer, a metal shielding layer, and a non-woven fabric tape, and an outer sheath is extruded on the outermost layer of the cable core.

As a further improvement, there are three main wire cores, which are composed of a main wire conductor, a conductor shield extruded outside the main wire conductor, insulation of the main wire core, an insulating shielding layer, and a phase-separated copper tape shielding layer.

As a further improvement, there are three auxiliary wire cores, which are composed of auxiliary wire conductors and auxiliary wire insulating layers extruded outside the auxiliary wire conductors.

As a further improvement, the isolation layer is composed of two overlapping layers of polyethylene tape.

As a further improvement, the turnkey metal shielding layer is a structure of copper strips overlapping and wrapping. the

The beneficial effects of the utility model are:

Compared with the existing technology, the medium-voltage variable frequency power cable has a phase-separated shielding layer and an all-inclusive shielding layer. The phase-separated shielding layer is a channel for the leakage current or short-circuit current of the cable during work, and can protect the cable line. The shielding layer has the effect of preventing external electromagnetic signal interference; and the main wire core is the channel for transmitting current, and the auxiliary wire core can be used as a neutral wire or a ground wire, which provides a guarantee for the normal operation of the frequency conversion equipment.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Detailed ways

As shown in Figure 1, a medium-voltage variable-frequency power cable described in the utility model includes a cable core, and the cable core is formed by twisting three main cores and three secondary cores alternately; There is a filling layer 8, and the cable core is wrapped with an isolation layer 9, a metal shielding layer 10, and a non-woven fabric tape 11 from inside to outside in sequence, and an outer sheath 12 is extruded on the outermost layer of the cable core. The main line core is composed of main line conductor 1 and conductor shielding 2, main line core insulation 3, insulating shielding layer 4, and phase-separated copper tape shielding layer 5 extruded successively outside the main line conductor 1; the secondary line core is The three wires are composed of the secondary conductor 6 and the secondary insulating layer 7 extruded outside the secondary conductor 6 .

There are many specific application ways of the utility model, and the above descriptions are only the preferred implementation modes of the utility model. Improvements, these improvements should also be regarded as the protection scope of the present utility model.

Claims (5)

1. A medium-voltage variable frequency power cable, characterized in that: it includes a cable core, and its cable core is formed by arranging and twisting several main cores and several secondary cores; a filling layer ( 8), wrap the isolation layer (9), all-inclusive metal shielding layer (10), and non-woven fabric tape (11) from inside to outside in turn around the cable core, and extrude the outer sheath (12) on the outermost layer of the cable core. 2. The medium voltage variable frequency power cable according to claim 1, characterized in that there are three main wire cores, which are shielded by the main wire conductor (1) and the conductor shielding (2 ), main core insulation (3), insulation shielding layer (4), and phase-splitting copper tape shielding layer (5). 3. The medium voltage variable frequency power cable according to claim 1, characterized in that there are three auxiliary wire cores, which are composed of the auxiliary wire conductor (6) and the auxiliary wire extruded outside the auxiliary wire conductor (6). Insulation layer (7) constitutes. 4. The medium-voltage variable-frequency power cable according to claim 1, characterized in that, the isolation layer (9) is composed of two overlapping layers of polyethylene tape. 5. The medium-voltage variable-frequency power cable according to claim 1, characterized in that, the turnkey metal shielding layer (10) is a copper tape overlapping wrapping structure.

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