1. Oil-impregnated paper insulated power cable Power cable with oil-impregnated paper as insulation. Its application history is the longest. It is safe and reliable, has a long service life and is inexpensive. The main disadvantage is that the laying is limited by the drop. Since the development of non-drip paper-impregnated insulation, the problem of drop limit has been solved, allowing oil-impregnated paper-insulated cables to continue to be widely used.

2. Plastic insulated power cables Power cables whose insulation layer is extruded plastic. Commonly used plastics are polyvinyl chloride, polyethylene, and cross-linked polyethylene. The plastic cable has the advantages of simple structure, convenient manufacturing and processing, light weight, convenient laying and installation, and is not limited by the laying drop. Therefore, it is widely used as medium and low voltage cables, and has a tendency to replace sticky impregnated oil-paper cables. Its biggest disadvantage is the presence of dendritic breakdown, which limits its use at higher voltages.

3. Rubber insulated power cable The insulating layer is made of rubber plus various compounding agents. After fully mixing, it is extruded and wrapped on the conductive wire core, and is formed by heating and vulcanization. It is soft and elastic, suitable for frequent movement and small bending radius.