Characteristic power requirements for performing various functions in underground coal mines

Many changes in coal mining methods have been taking place during the past two decades as a result of mechanization. Electrical motor drives are now used for a great variety of functions. In order to design proper underground power transmission and distribution circuits, to select the correct size and location of transforming or converting units, and to estimate power supply needs and costs, it is desirable to determine typical demand and energy-consumption requirements for both individual operations and area needs.