CN206564143U - Power cable - Google Patents

Abstract

The utility model discloses a power cable, include: an outer sheath; a shielding sheath disposed within the outer sheath; the six phase lines with the insulation are uniformly distributed on the periphery of the grounding wire and are in a three-phase geometric symmetrical arrangement structure, wherein two phase lines with the insulation are arranged in the same phase and are symmetrically arranged at 180 degrees relative to the grounding wire; and the insulating filler is filled between the shielding sheath and the phase line with the insulating layer. The utility model discloses a power cable can reduce power cable electromagnetic interference, distributed capacitance and operating temperature, extension power cable life. The utility model discloses a power cable is applicable to converter power cable.

Description

power cable

technical field

The utility model relates to the technical field of electric power, in particular to a power cable.

Background technique

Currently used power cables generally use three-phase three-wire cables, three-phase four-wire cables, or shielded three-phase three-wire plus three-ground cables. The disadvantages are poor Electro Magnetic Compatibility (EMC). The international patent WO 82/01785 "High Voltage Cable" discloses a shielded cable with three phase wires and three ground wires staggered to reduce electromagnetic interference, but it still does not completely reduce electromagnetic interference. In addition, the power cables in the prior art also have the following disadvantages: large distributed capacitance, short service life, and high operating temperature.

Utility model content

The embodiment of the utility model provides a power cable, which is used to reduce the electromagnetic interference, distributed capacitance and operating temperature of the power cable, and prolong the service life of the power cable. The power cable includes:

outer sheath 110;

a shielding sheath 109 placed within the outer sheath 110;

Six insulated phase wires 101-106 and one ground wire 107 placed in the shielding sheath 109, the six insulated phase wires 101-106 are evenly distributed on the periphery of the ground wire 107, in a three-phase geometrically symmetrical arrangement structure, in which the same phase There are two insulated phase wires, and they are arranged symmetrically at 180 degrees with respect to the ground wire 107;

The insulating filler 108 filled between the shielding sheath 109 and the insulated phase wire.

In one embodiment, the cross-sectional areas of each insulated phase wire and the ground wire 107 are equal, and the cross-sections of the six insulated phase wires 101-106 are all tangent to the ground wire 107, and the cross-sections of adjacent insulated phase wires are tangent.

In one embodiment, the colors of the three-phase insulated phase wires are different.

In one embodiment, among the three-phase insulated phase wires, the insulated phase wire of phase A is yellow, the insulated phase wire of phase B is green, and the insulated phase wire of phase C is red.

In one embodiment, the ground wire 107 is a bare wire.

In one embodiment, the shielding sheath 109 is made of metal, fully enclosed and wrapped outside the insulated phase wire and the ground wire 107 .

In one embodiment, the insulating filler 108 is also filled between the insulated phase wire and the ground wire 107 .

In one embodiment, the insulating filler 108 is made of cross-linked polyethylene and flame-retardant polypropylene.

In one embodiment, the outer sheath 110 is made of flame-retardant polyvinyl chloride material.

In one embodiment, the power cable is a frequency converter power cable.

The power cable of the embodiment of the utility model includes: an outer sheath; a shielding sheath placed in the outer sheath; six insulated phase wires and a grounding wire placed in the shielding sheath, and the six insulated phase wires are evenly distributed On the periphery of the grounding wire, there is a three-phase geometrically symmetrical arrangement structure, in which there are two insulated phase wires in the same phase, and they are arranged symmetrically at 180 degrees relative to the grounding wire; the insulation between the shielding sheath and the insulated phase wire is filled Filler; in this way, the three-phase symmetry is electrically connected in parallel, so that the carrying capacity of the phase wires is 50% of that of the traditional cable; a space-balanced symmetrical structure is formed, so that the middle position of the six-phase wires of the power cable reduces the intensity of the alternating magnetic field, and at any time, The sum of the three-phase currents is zero, and the vector sum of the alternating magnetic field is zero, which greatly reduces the inductance and capacitance generated by the induction of the power cable, and reduces the electromagnetic interference between the three phases of the power cable, as well as the traditional three-phase Compared with the external radiation interference intensity of the three-wire power cable, it is reduced by half; the operating temperature is reduced; and the service life of the cable is extended.

Further, the power cable of the embodiment of the present utility model is suitable for a power cable of a frequency converter.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings based on these drawings without creative work. In the attached picture:

Fig. 1 is a schematic structural diagram of a power cable in an embodiment of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiment of the utility model clearer, the embodiment of the utility model will be further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiment of the utility model and its description are used to explain the utility model, but not as a limitation to the utility model.

Fig. 1 is a schematic structural diagram of a power cable in an embodiment of the present invention. As shown in Figure 1, the power cable in the embodiment of the utility model can include:

outer sheath 110;

a shielding sheath 109 placed within the outer sheath 110;

Six insulated phase wires 101-106 and one ground wire 107 placed in the shielding sheath 109, the six insulated phase wires 101-106 are evenly distributed on the periphery of the ground wire 107, in a three-phase geometrically symmetrical arrangement structure, in which the same phase There are two insulated phase wires, and they are arranged symmetrically at 180 degrees with respect to the ground wire 107;

The insulating filler 108 filled between the shielding sheath 109 and the insulated phase wire.

It can be seen from the structure shown in Figure 1 that the power cable of the embodiment of the utility model adopts a three-phase seven-wire structure, and the three-phase geometrically symmetrical arrangement structure forms an electrical parallel connection, so that the current carrying capacity of the phase lines is 50% of that of the traditional cable. %; In terms of physical location, the outer 6 lines of the grounding line are arranged in the position of two three-phase power lines in a staggered inverted triangle, that is, the same phase lines are arranged at 180 degrees, forming a spatially balanced and symmetrical structure, so that the middle of the six-phase lines of the power cable The location reduces the intensity of the alternating magnetic field, and at any time, the sum of the three-phase currents is zero, and the vector sum of the alternating magnetic field is zero, which greatly reduces the inductance and capacitance generated by the induction of the power cable, and reduces the distance between the three phases of the power cable. The electromagnetic interference generated by each other, and the external radiation interference intensity is reduced by half compared with the traditional three-phase three-wire power cable; the operating temperature is reduced; and the service life of the cable is extended.

It can be seen from the structure shown in Figure 1 that the power cable of the embodiment of the utility model adopts a 7-core, double-three-phase three-wire physical space position in an inverted triangle arrangement, and the middle core is a shielded cable. The six insulated phase wires 101-106 surround the grounding wire 107, and the conductors conform to the national standard GB3956 during implementation, and a standard compact structure can be used.

In a specific embodiment, the cross-sectional areas of each insulated phase wire and the ground wire 107 are equal, and the cross-sections of the six insulated phase wires 101-106 are all tangent to the ground wire 107, and the cross-sections of adjacent insulated phase wires are tangent.

In a specific embodiment, the colors of the three-phase insulated phase wires are different.

In a specific embodiment, the phase wires are distinguished by color, for example: among the three-phase insulated phase wires, the insulated phase wire of phase A is yellow, the insulated phase wire of phase B is green, and the insulated phase wire of phase C is red . When the cables are connected, for example in FIG. 1 , the three-phase power supply phase line A can be connected with insulated phase lines 101 and 104 , B can be connected with insulated phase lines 102 and 105 , and C can be connected with insulated phase lines 103 and 106 .

In a specific embodiment, the ground wire 107 is a bare wire.

In a specific embodiment, the shielding sheath 109 is made of a metal material, fully enclosed and wrapped outside the insulated phase wire and the ground wire 107, for example, it can be made of a metal material with good conductivity and fully enclosed outside all the wires.

In a specific embodiment, the insulating filler 108 is also filled between the insulated phase wire and the ground wire 107 .

In a specific embodiment, the insulating filler 108 can be made of materials that meet national standards such as physical and mechanical properties and flame retardancy, for example, materials such as cross-linked polyethylene and flame-retardant polypropylene can be used. Here, the cross-linked polyethylene and flame-retardant polypropylene composite material is just an example, and its physical and mechanical properties and flame-retardant performance indicators meet the national standard GB/T12706-2008. Of course, other materials with national standards such as physical and mechanical properties and flame retardancy can also be used according to requirements during implementation.

In a specific embodiment, the outer sheath 110 can be made of materials that meet national standards such as physical and mechanical properties and flame retardancy, for example, materials such as flame-retardant polyvinyl chloride can be used. The flame-retardant polyvinyl chloride material here is just an example, and its physical and mechanical properties and flame-retardant performance indicators meet the national standard GB/T12706-2008. Of course, other materials with national standards such as physical and mechanical properties and flame retardancy can also be used according to requirements during implementation.

In a specific embodiment, the power cable is a frequency converter power cable, and a frequency converter can be used as a power cable output by a power supply.

To sum up, the power cable of the embodiment of the utility model includes: an outer sheath; a shielding sheath placed in the outer sheath; six insulated phase wires and a grounding wire placed in the shielding sheath, and six wires with The insulated phase wires are evenly distributed on the periphery of the grounding wire, in a three-phase geometrically symmetrical arrangement structure, in which there are two insulated phase wires in the same phase, and they are arranged symmetrically at 180 degrees relative to the grounding wire; filled in the shielding sheath and the insulated phase wire The insulating filler between the wires; in this way, the three-phase symmetry is electrically connected in parallel, so that the current carrying capacity of the phase wires is 50% of that of the traditional cable; a space-balanced and symmetrical structure is formed, so that the middle position of the six-phase wires of the power cable reduces the alternating magnetic field intensity, And at any time, the three-phase current sum is zero, and the alternating magnetic field vector sum is zero, which greatly reduces the inductance and capacitance generated by the induction of the power cable, and reduces the electromagnetic interference generated between the three phases of the power cable, and Compared with the traditional three-phase three-wire power cable, the intensity of external radiation interference is reduced by half; the operating temperature is reduced; and the service life of the cable is extended.

Further, the power cable of the embodiment of the utility model is suitable for frequency converter power cables, and can provide a frequency converter with three-phase AC transmission in the frequency converter system that reduces the distributed capacitance of the cable and the alternating electromagnetic of the cable, reliable grounding, and good shielding power cable.

The power cable of the embodiment of the utility model can bring economic benefits and is beneficial to market promotion.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present utility model in detail. Within the protection scope of the utility model, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the utility model shall be included in the protection scope of the utility model.

Claims (10)

1. A power cable, characterized in that, comprising: outer sheath (110); A shielding sheath (109) placed inside the outer sheath (110); Six insulated phase wires (101-106) and one ground wire (107) placed in the shielding sheath (109), the six insulated phase wires (101-106) are evenly distributed on the periphery of the ground wire (107), It is a three-phase geometrically symmetrical arrangement structure, in which there are two insulated phase lines in the same phase, and they are arranged symmetrically at 180 degrees relative to the grounding line (107); An insulating filler (108) filled between the shielding sheath (109) and the insulated phase wire. 2. The power cable according to claim 1, characterized in that, the cross-sectional areas of each insulated phase wire and ground wire (107) are equal, and the six insulated phase wires (101-106) are all connected to the ground wire (107) The sections are tangent, and the sections of adjacent insulated phase wires are tangent. 3. The power cable according to claim 1, characterized in that the colors of the three-phase insulated phase wires are different. 4. The power cable according to claim 3, characterized in that, among the three-phase insulated phase wires, the insulated phase wire of A phase is yellow, the insulated phase wire of B phase is green, and the insulated phase wire of C phase is red . 5. The power cable according to claim 1, characterized in that, the ground wire (107) is a bare wire. 6. The power cable according to claim 1, characterized in that, the shielding sheath (109) is made of metal, fully enclosed and wrapped outside the insulated phase wire and the ground wire (107). 7. The power cable according to claim 1, characterized in that, the insulating filler (108) is also filled between the insulated phase wire and the ground wire (107). 8. The power cable according to claim 1, characterized in that the insulating filler (108) is made of cross-linked polyethylene and flame-retardant polypropylene. 9. The power cable according to claim 1, characterized in that, the outer sheath (110) is made of flame-retardant polyvinyl chloride material. 10. The power cable according to any one of claims 1 to 9, characterized in that the power cable is a frequency converter power cable.