In actual production process, scraper conveyor had problems of empty load or light load, electrical energy waste and physical deterioration. Through analysis of relation between frequency converter and load change, energy saving approaches were reached in actual production. Taking scraper conveyor controlled by frequency converter in 4507 working face as an example, power factors and tons of coal consumption of electricity were got by running under two modes of power frequency and frequency conversion, which showed that power factor maintained at above 0.9 and energy-saving rate reached 18 %.