Power cable structure
The power cable is composed of three main parts: a conductive core, an insulating layer and a protective layer.
1. Conductive core
The conductive core is used to transport current, and must have good conductivity, a certain tensile strength, and elongation. The conductive core of the power cable is usually made of copper, aluminum stranded wire or multiple stranded soft copper wire.
2. Insulation layer
The function of the insulating layer is to electrically isolate the conductive core from the outside and ensure that the current is transmitted along the direction of the core. The quality of insulation directly affects the quality of cable operation: the insulation level of the insulation material determines the voltage level of the power cable.
3. Protective layer
The protective layer is to adapt the cable to the requirements of various use environments. The protective covering layer outside the insulating layer is mainly used to protect the cable from mechanical damage and various environmental factors such as water and sunlight during laying and operation. , Biological, fire, etc. to maintain stable electrical performance. The protective layer of the cable is directly related to the life of the cable. The protective layer is divided into an inner protective layer and an outer protective layer.
The inner protective layer is directly wrapped on the insulating layer, and the protective insulation cannot be in contact with other substances. Therefore, it must be tightly and seamlessly wrapped and have a certain mechanical strength to enable it to withstand the mechanical force during transportation and laying. The inner protective layer includes lead, aluminum, rubber, PVC, etc.
The outer protective layer is used to protect the inner protective layer to prevent the pin bag, aluminum bag, rubber polyvinyl chloride, etc. from being mechanically damaged and corroded by the outside. The outer layer of the inner protective layer of the cable is soaked with jute mixture of asphalt Steel belt or steel wire pin, PVC, etc. A cable without an outer protective layer, such as a packaged cable, is used where there is no mechanical damage."
In addition, cross-linked cables have semiconductor shields and metal shields.