The traction power supply system of electrified railway is mainly composed of power supply, substation, catenary and electric locomotive. Power supply is the starting point of the system, which usually obtains electric energy from the national grid and then transmits it to the substation of the railway system through special transmission lines. The main task of substation is to convert electric energy into electric energy suitable for electric locomotive and control the quality of electric energy to ensure the safe and stable operation of electric locomotive. Catenary is a device that directly supplies electric energy to electric locomotives, and many factors need to be considered, including transmission efficiency of electric energy, mechanical strength and environmental impact. The electric locomotive is connected with the catenary through the pantograph to obtain the electric energy needed for operation. To sum up, the traction power supply system of electrified railway is a complex and precise system, and its various components are interrelated to ensure the normal operation of the railway system together.

In the future, with the development and innovation of technology, we have reason to believe that the traction power supply system of electrified railway will become more efficient, environmentally friendly and safe.