Industry News

  Power cables are designed to withstand high temperatures and extreme operating voltages over long periods. They can be installed in various environments, offering safe, concealed operation unaffected by external climate changes. Additionally, they require minimal maintenance and are highly durable, typically with a service life of over 40 years.

1. Polyvinyl Chloride (PVC) Insulated Power Cables

  PVC plastic is cost-effective, offers good physical and mechanical properties, and is easy to extrude, though its insulation performance is moderate. As a result, PVC-insulated cables are widely used to manufacture low-voltage power cables rated at 1 kV and below, serving low-voltage distribution systems. Annual production exceeds tens of thousands of kilometers. When voltage-stabilized insulating materials are used, PVC cables can also be produced for 6 kV applications.

2. Cross-Linked Polyethylene (XLPE) Insulated Power Cables

  Polyethylene boasts excellent electrical insulation properties. After cross-linking, it becomes a thermosetting material, offering superior electrical performance, mechanical strength, and heat resistance. Over the past two decades, XLPE cables have become the leading choice for medium- and high-voltage power cables in China, suitable for voltage levels ranging from 6 kV to 330 kV. In recent years, the cross-linking of 1 kV low-voltage cables has emerged as a technological trend, with the key challenge being to reduce insulation thickness to compete cost-effectively with PVC cables.

3. Viscous Oil-Impregnated Insulated Power Cables

  Before 1992, this type was the dominant medium-voltage cable in China. With a history spanning over a century, this classic power cable structure offers ample electrical and thermal performance margins and a long service life (some imported cables installed as early as 1923 are still in use in China). However, due to complex production processes, long manufacturing cycles, and scarce raw materials, they have largely been replaced by XLPE cables.

4. Oil-Filled Cables

  Another structural variant of oil-paper cables, oil-filled cables use thin insulating paper wrapped around the conductor, with low-viscosity oil pressurized to fill the gaps. Suitable for 66–500 kV applications, these were China's primary high-voltage cables from the 1960s. However, they have also been largely superseded by XLPE insulated high-voltage cables in recent years.

5. Rubber Insulated Power Cables

  These flexible, movable power cables are mainly used in settings where frequent repositioning is required, such as industrial facilities. Natural rubber insulation is used, with voltage ratings primarily up to 1 kV, though 6 kV versions can also be produced.

6. Aerial Insulated Cables

  Essentially insulated overhead conductors, these cables are still installed on utility poles but with lower insulation design margins compared to power cables. The insulation can be made of PVC or XLPE. They are generally manufactured as single-core cables but can also be twisted into a bundle without a sheath, known as bundled aerial cables.

Conclusion

  With six main types of power cables available, selection should be based on factors such as voltage level, application environment, and project budget to ensure optimal performance and cost-effectiveness.