Regeneration Energy Management in AC Mining Drives for Providing Control Power

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 regenerated energy is as high as 60% of the peak motoring power. This regenerated energy can be stored temporarily and then reused. 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 for regenerative energy storage to provide control power source for medium voltage gas insulated switchgear. Energy calculation and design of the ultracapacitor system into the existing converter system is presented.