As the axial fan has 4000 hr per year regulated speed in motion in Anqin Copper Mines Xifeng Well, so applied reconstruction of liquid resistance regulated speed technology, it can recomize power cost RMB 200 thousand.

Thte starting characteristics of mine fan driven by coiled asynchronous motor in series connection with symmetric liquid resistances to the rotor is analysed,and the calculating method of liquid resistance is introduced.

To meet the needs of different applications and loads, the conventional starting mode of the high-voltage cage liquid resistance starter is improved.

Introduce the working principle and structure feature of the liquid resistance slip controller,and the using characteristics and the controlling method of the liquid resistor slip controller on the percussion load;Discuss the using effects of the liquid resistance by comparing the regulation style with other slip adjustment.

The similarities and differences of high voltage heat Changing Resistance type starter and liquid resistance starter of moving pole plate in application of soft start up of high voltage squirrel cage motor are presented in detail, so as to understand and reasonably select the two resistance starters.

Liquid resistance starter used to realize start-up of constant torque of the winding asynchronous motor are presented in this paper.