How to drive a train?

Starting means lifting the handle directly. Under normal circumstances, the friction between the wheel and the rail is enough to start the train. If there is oil pollution on the track or the friction decreases in rainy and snowy weather, you can slowly raise the traction current of the locomotive by slowly lifting the handle, and then slowly start the train. Otherwise, you can step on the sand valve to increase the friction between the wheel and the rail to start the train. For heavy-haul freight trains that are difficult to start, the method of "stopping" can be adopted, that is, the driver first controls the locomotives to retreat a little, so that the couplers of each train change from a stretched state to a compressed state (generally at least 2/3 compressed), and then the train is started, so that the whole train can be started one by one. At present, most locomotives have two braking methods: air braking and dynamic braking. Air braking means that the driver operates the brake (brake) on the locomotive to brake or relieve the train by emptying the train pipe or inflating the train. The small brake can also be operated separately to inflate/deflate the locomotive brake cylinder to brake/release the locomotive. Dynamic braking is only carried out on locomotives or power cars, and it can be divided into two categories: resistance braking and regenerative braking. Most locomotives in our country adopt the dynamic braking mode of resistance braking. The principle of this mode is: when dynamic braking is carried out, the traction motor of the train locomotive or power car becomes a generator, so that the kinetic energy of the train becomes electric energy; If electric energy is transmitted to the braking resistor and converted into heat energy, it is resistive braking; If the electric energy is sent back to the catenary through the pantograph (electric locomotive) for recycling, it is regenerative braking. Due to technical problems, regenerative braking has not been widely promoted in China for the time being.