Energy Budget Reduction by Using Ultracapacitors in Mining Converters

A typical mining facility uses excavation machines like shovels, draglines etc. for removing overburden and ores during the mining process. These machines are characterized by cyclic loads consisting of high peak power demands as well as regenerative energy. The peak power demand is often as high as double the average demand. The regenerated energy is as high as 60% of the peak motoring power. This regenerated energy can be stored temporarily and then reused during peak motoring demand thus leading to peak-shaving of the load. The recent development in the field of ultracapacitors has led to commercial availability of high power ultracapacitor modules rated for reasonably high voltages. The paper proposes the use of ultracapacitors in order to peak load shaving thereby reducing energy costs. The paper also discusses the economic benefits achieved by adopting this technology.