What are the general reasons for large-scale power outages?

1) irresistible natural external force injury. From a lot of practical work experience, we can know that the main reason for the damage of power equipment in power system is the damage of natural external forces. For example, severe icing leads to line disconnection and galloping, leading to short circuit failure; Line insulator flashover fault caused by condensation, freezing fog and lightning; Overhead line flashover tree, etc. In 2008, the snowstorm in southern China caused a large-scale power outage, which was caused by extremely disastrous weather.

2) Power equipment failure. Power equipment is the most important equipment for power transmission, distribution and dispatching. Power equipment failure is the most common form that leads to large-scale power failure in power system. In addition to the above-mentioned equipment failures caused by the external damage of climate and natural environment, the abnormal electrical and mechanical performance of the equipment itself may also lead to equipment failures such as "refusing to move" and "misoperation", or even the failure of the whole equipment function.

3) The imbalance between supply and demand of power demand side is destroyed. For some reasons, the sudden fluctuation of demand-side power load or power generation capacity leads to a serious imbalance between power supply and demand in power system, which is another main reason for large-scale power outage in power system. The sudden increase or decrease of demand-side load caused by climatic conditions, the terminal of the receiving transmission channel and the disconnection of important loads in the system may all cause the imbalance between supply and demand on the demand side, and then cause a large-scale power outage.

4) Man-made destruction. In the process of electric energy production, transmission, distribution and consumption, human error may cause large-scale power failure. In addition, the destruction of terrorists and disgruntled extremists will also cause large-scale power outages.

5) Insufficient management. Perfect management system and practical management implementation are important guarantees for the safe and stable operation of power system. The production, transmission, distribution and consumption of electric energy in power system are inseparable from perfect and reliable management. If the management system is not perfect, the management is not strong, and the management is not in place, the actual management mode may not be able to effectively adapt to various influencing factors existing in complex large power grids, thus leading to large-scale power outage accidents in power systems.