REVERSIBLE ELECTRIC BATTERY SUPPLIED TRACTION SYSTEM
Problem:
A 52 ton diesel maintenance loco is not allowed to operate diesel engine in tunnels and requires to move electrically, without connecting to the third rail, as this is de-energized during maintenance.
Solution:
Fully reversible traction system (inverter + motor) powering the loco in tunnels from batteries, and then recharges batteries from same motor when loco runs on diesel out of tunnels.