That's not how modern trains generally work although it's possible that's how India's trains still work. Usually there's a HEP (head-end power) generator on th

That's not how modern trains generally work although it's possible that's how India's trains still work. Usually there's a HEP (head-end power) generator on the locomotive and the rest of the coaches are just plugged into that/each other to distribute the power down the train. Most regions have standard connectors/voltages and such to make this pretty seamless.