Taking the hydraulic coupling as a main regulating mode

it is the development direction of controls for induced draft funs(IDF)in the future.In practical application

however

it can have certain effect upon the requlation

performance of furnace pressure due to the regulating behavior of the hydraulic coupling proper and the matching problem in equipment selection.For this

an automatic control method of combined regulation for hydraulic coupling and stationary blades has been put forward.On the basis of test parameters in cold-state ventilation and output capability test of the IDF

the automatic control of IDF in Sanhe Power Plant has been retrofitted based on the regulation behavior of stationary blades and hydraulic coupling of IDF.Test results show that the control system after retrofitting both solved the non-matching problem existing in combined regulation of hydraulic coupling and stationary blades in IDF of Sanhe Power Plant and having satisfied the control requirements in RB and MFT inclement operating conditions.