Performance improvement of mining haul trucks operating on trolley systems

A typical mining facility uses off-road mining trucks to haul materials, such as coal, ore, and overburden from the pit to a stockpile where the material can be stored or processed. A conventional haul truck operates with diesel engine, adding considerable fuel expenses to the entire mining operation. The objective of the mines is to achieve the movement of the highest possible payload per hour while minimizing operating costs over the lifetime of the machines. Operating the trucks with power from the overhead trolley lines, especially while going up on a grade significantly increases productivity, reduces fuel costs and qualifies as a green solution. One of the major concerns of using trolley system is the availability of the trolley line, which affects the productivity directly since one or more trucks rely on the trolley line. The possible fault influencing the availability comes from the various operating parameters of the truck as well as the design of the trolley system. Whenever a fault occurs, it is desirable to isolate this truck for maintenance without affecting the substations and the other trucks on the same line. This paper presents the performance improvement of the trolley assisted haul trucks and their solutions through simulation study and field experimental results.