2. Power system is a power production and consumption system consisting of power generation, transmission, substation, distribution and electricity consumption. It converts the primary energy in nature into electric energy through power generation devices, and then supplies the electric energy to all users through transmission, transformation and distribution. It mainly includes power generation equipment and power supply equipment. Power generation equipment mainly includes power station boilers, steam turbines, gas turbines, water turbines, generators, starters, transformers, etc. Power supply equipment mainly includes transmission lines, transformers and contactors of various voltage levels.