High voltage Power cable XLPE Cable (YJV Cable)-3

详情

• General Introduce：Crosslinked polyethylene insulated cable is a type of cable suitable for distribution networks and other fields, with advantages that PVC insulated cables cannot compare. It has a simple structure, light weight, good heat resistance, strong load capacity, non melting, chemical corrosion resistance, and high mechanical strength.
• Theory:Cross linked polyethylene insulated cable uses chemical or physical methods to change the cable insulated polyethylene molecule from linear molecular structure to main network molecular structure, that is, thermoplastic polyethylene into thermosetting crosslinked polyethylene, thus greatly improving its heat resistance and mechanical performance, reducing its shrinkage, making it no longer melt after being heated, and maintaining excellent electrical performance.
• Characters:The cross-linked polyethylene insulated cable adopts peroxide cross-linking method to change the polyethylene molecule from linear molecular structure to three-dimensional network structure, and from thermoplastic material to thermosetting material. The working temperature is raised from 70 ℃ to 90 ℃, significantly improving the current carrying capacity of the cable. Crosslinked polyethylene insulated cables have the following advantages:
  
  1. Heat resistance: XLPE with a three-dimensional network structure has excellent heat resistance. It will not decompose or carbonize below 300 ℃, and can work at a long-term temperature of up to 90 ℃, with a thermal life of up to 40 years.
  
  2. Insulation performance: XLPE maintains the original good insulation characteristics of PE, and the insulation resistance further increases. The tangent value of its dielectric loss angle is very small and is not significantly affected by temperature.
  
  3. Mechanical properties: due to the establishment of new Chemical bond between macromolecules, the hardness, rigidity, wear resistance and impact resistance of XLPE are improved, thus making up for the defect that PE is prone to crack due to environmental stress.
  
  4. Chemical resistance characteristics: XLPE has strong acid, alkali, and oil resistance. Its combustion products are mainly water and carbon dioxide, which pose little harm to the environment and meet the requirements of modern fire safety.​​
• Application:Crosslinked polyethylene insulated cables are suitable for distribution networks, industrial installations, or other areas that require high capacity electricity consumption. Low voltage cables are used for fixed installation on power transmission and distribution lines with a rated voltage of 3.6/6-26/35KV at 50Hz AC,and their main function is to transmit electrical energy.
• Problems:Although cross-linked polyethylene (XLPE) has many outstanding advantages as an insulation material and has developed some excellent products after years of effort, there are still some important issues that need to be addressed. Improving voltage level and capacity is the development direction of high-voltage DC XLPE insulated cable products, which also puts forward corresponding technical requirements.
  From the technical point of view, the space charge generated and accumulated by XLPE insulated cables in the process of High-voltage direct current transmission is the most important problem that polymer insulation materials need to face, which always limits the application of polymer insulation materials in High-voltage direct current cables. So, the mechanism of space charge accumulation and the suppression of space charge accumulation are the focus of research, including the corresponding research on the interface properties of semiconductors and insulators in polymer insulated cables, the interface properties of insulators, the influence of temperature gradients on space charge generation, and the process of space charge accumulation.
  ​Of course, it also includes other issues: the mechanism of insulation material aging, the long-term stability of new materials, and the impact of partial discharge. It is not yet clear whether the upper limit of operating voltage should be determined by the measurement of space charge or by the threshold voltage of electrical aging.