Boost fan RUNBACK (RB) control method based on boost fan system state monitoring

The invention relates to a boost fan RUNBACK (RB) control method based on boost fan system state monitoring. The boost fan RB control method comprises the steps of judging whether there is an abnormal working condition that a boost fan does not trip but cannot output power or not in the operation process according to boost fan inlet pressure, boost fan outlet pressure and the boost fan motor electric current change situation, triggering boost fan system abnormal RBs in time when the abnormal working condition is detected, and carrying out a series of protection actions. Compared with the prior art, the boost fan RB control method has the advantages that the abnormal working condition that the boost fan cannot output power is judged in time when the boost fan does not trip, quick load reduction of a unit is realized, and safe and stable operation of the unit is maintained.