Abstract: In order to reduce the energy consumption of the mine，the mine energy-saving technolo⁃ gy was studied in view of the shortage of the existing frequency conversion technology，the large number of mine electrical equipment，high power and high energy consumption. An intelligent energy-saving device including high-voltage energy-saving and soft-start was developed，which was combined into a constant speed and fast response device. The application test of HP500 crusher in metal mine proved that the ener⁃ gy-saving rate was more than 10% and the energy-saving effect was remarkable. The principle of stepdown energy saving can effectively reduce the energy consumption of the motor under large current impact load and constant medium and high load conditions，which promotes the development of motor energy sav⁃ ing technology to a certain extent and has reference and promotion value for similar mines.

Key words: speed and fast response, energy saving technology, mine application