Large scale surface power stations in China are generally located in the west. These places are generally desert, saline alkali land and large diurnal temperature difference. Rat damage is also serious and the environment is very humid. The requirements for cable buried laying and cable trench filling and excavation are relatively high; The operating environment of the distributed power station cable is not better than that of the ground. The cable can withstand very high temperature. The roof temperature can even reach 100-110 ℃ under the measurement and control of technicians. The requirements for fire resistance and flame retardancy of the cable and the high temperature have a great impact on the insulation breakdown voltage of the cable. Therefore, the following points shall be considered in the model selection design:

1. Insulation performance of cable

2. Moisture, cold and weather resistance of cables

3. Heat resistance and flame retardancy of cables

4. Cable laying method

5. Conductor material of cable (copper core, aluminum alloy core, aluminum core)

6. Cable section specification

There are three main causes of cable grounding fault.

First, cable manufacturing defects are unqualified products;

Second, the operating environment is bad, natural aging, and external damage;

Third, the installation is not standardized and the wiring is rough. The root cause of ground fault is only one - cable insulation.