Power cables are the fundamental carriers used for transmitting and distributing electrical energy in the power system, often referred to as the underground arteries of urban power grids. Compared to overhead power lines, power cables laid underground or in tunnels are less affected by external environmental factors such as wind, rain, and lightning strikes, occupying less ground space. They are widely used in densely populated urban areas.

A complete power cable generally consists of several parts: conductor, insulation layer, shielding layer, and outer sheath. Conductors are responsible for conducting current, and copper and aluminum are commonly used conductor materials; The insulation layer isolates live conductors and prevents leakage, which is a key structure to ensure electrical safety; The outer sheath resists erosion caused by soil, water vapor, acidic and alkaline substances, reducing the risk of damage caused by external pulling and squeezing.

According to voltage levels, power cables can be classified into low voltage, medium voltage, high voltage, and other categories. Low voltage cables are commonly used for internal power distribution in buildings, transporting electrical energy to residential areas and shopping malls; Medium and high voltage cables undertake the task of power transmission between regional substations. In urban renovation projects, many overhead line grounding projects use environmentally friendly power cables to reduce safety hazards and beautify urban spaces.

The operation status of cables will affect the stability of power supply. During laying construction, excessive bending and dragging should be avoided to damage the protective sheath. After being put into use, regular inspections are required to observe whether there is abnormal heating or damage to the outer skin of the cable joints. Insulation testing should be carried out regularly to prevent long-term overload operation, delay the aging of insulation materials, and ensure the smooth operation of the power supply line.