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How does a diesel-electric locomotive turn diesel engine power into motion?
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diesel engine
Diesel engine equipped with a precombustion chamber.
A diesel-electric locomotive functions as an electric locomotive that carries its own onboard power plant, converting the mechanical energy produced by the diesel engine into electrical current to drive the wheels.12
The process generally follows these steps:
- Power Generation: The diesel engine burns fuel to produce mechanical energy. This engine is coupled to an electrical generator or an alternator.1
- Current Conversion: If an alternator is used, it produces three-phase alternating current. In many systems, this is passed through static rectifiers to convert it into direct current for the traction motors.1
- Propulsion: The electrical current is fed to traction motors, which power the locomotive's axles to create motion.1
In more modern designs, particularly those using three-phase alternating-current motors, the system may use a thyristor-controlled inverter to convert the electrical supply into the specific voltage and frequency required by the motors. This electric transmission allows for precise control, including advanced features like "creep control," which uses microprocessors and sensors to optimize tractive force during acceleration.13