The power needed by the subway is not as simple as putting batteries in the subway cars and recharging them at night. The electric energy required by the subway is generally led to the train through the overhead contact line on the top of the subway tunnel or the third rail on the side of the walking rail, namely the current received by the overhead contact line and the third rail.
The subway is an electric locomotive, like the Beijing subway, using the DC 750V third rail power supply, the third rail is on the side wall, like Shanghai, Guangzhou subway, using the DC 1500V contact line power supply, the contact grid is above the track!
Overhead contact line flow, also known as traction network flow. I believe you should have seen the transmission lines that supply power to electric locomotives along the railway line, and these wires are overhead contact lines. During the train operation, the pantograph will be raised to contact with the catenary and introduce electric energy.
The same is true for the subway, which can be powered by overhead contact lines in the tunnels. However, in order to adapt to the narrow space in the subway tunnel, the catenary in the general tunnel adopts rigid catenary directly installed on the top of the tunnel. After the pantograph of subway locomotive contacts with catenary, electric energy is introduced into the locomotive.
Another widely used mode of receiving flow is the third rail receiving flow. The third rail is the third rail located on the side of the line, independent of the walking rail. During the process of train operation, the current receiver on the train and the upper or lower surface of the three rail contact to complete the power supply.
After the electric energy is introduced into the locomotive, it flows through the traction motor, and then flows out from the locomotive, and returns to the traction substation through the track, forming a current loop to provide uninterrupted stable and reliable power supply for the locomotive.
The power needed by the subway is not as simple as putting batteries in the subway cars and recharging them at night. The electric energy required by the subway is generally led to the train through the overhead contact line on the top of the subway tunnel or the third rail on the side of the walking rail, namely the current received by the overhead contact line and the third rail.
The subway is an electric locomotive, like the Beijing subway, using the DC 750V third rail power supply, the third rail is on the side wall, like Shanghai, Guangzhou subway, using the DC 1500V contact line power supply, the contact grid is above the track!
Overhead contact line flow, also known as traction network flow. I believe you should have seen the transmission lines that supply power to electric locomotives along the railway line, and these wires are overhead contact lines. During the train operation, the pantograph will be raised to contact with the catenary and introduce electric energy.