Research on Engine Cranking Process in Downhill Braking Condition for an Electric Drive Underground Dump Truck

摘要

The retarder braking system of an electric drive dump truck is introduced in this paper. When the truck is going downhill at a low speed, part of the braking energy is consumed by braking resistance system, other energy is changed into AC power by inverter module, the diesel engine is dragged from an idling speed to a high speed by the synchronous motor, energy feedback is realized. In this paper, to achieve synchronous motor starting, a zero crossing detection and frequency searching method based on rotor speed sensor is used. The experiment shows the engine is started steadily and the current shock becomes flat.