Aiming at decreasing the unit auxiliary power consumption rate

some newly built generator units combined induced draft fan(IDF) with desulphurization booster fan

and adopted steam turbine to drive the IDF.However

this caused changing of IDF closed loop control(stator blade + speed control)

and variation of the unit run back(RB) control strategy.According to the problems occurred during the debugging and operation process of the steam turbine driven IDF control for a 1 000 MW unit

optimization measurements such as reserving speed control in the original variable structure

and changing static blade control into liner or manual way were proposed.Application results show that

the optimized control strategy for turbine driven IDF can satisfy the requirements

and has good control effect with unit auxiliary power consumption rate at less than 3%.