Recent advances in mining haul trucks

Electric mining haul trucks are one of the most challenging applications of power electronics in automotive systems. This paper presents some advances in very-high-power trucks used in copper mines. The special operational and environmental requirements for this application are highlighted. It is established that the use of inverter-fed three-phase induction motors with vector control is the preferred solution to reach the required high starting torque and good dynamic performance required by these vehicles. Packaging is a key issue and special attention is dedicated to the forced-air cooling system, because the air has a high dust level including conductive and corrosive materials. The truck's high-performance electric retarding system is described along with a novel use of trolley lines in a diesel boost mode as a way to increase the power and speed of the truck and reduce fuel consumption. Advanced features like remote monitoring, the use of global positioning systems and Internet diagnostics and troubleshooting are also discussed. The paper clearly shows that modern electric haul trucks are highly sophisticated systems that make full use of advances in modern technologies to increase safety and productivity levels.