抄録
A 2-loop feedwater control system has been developed for automatic transfer control of the reactor feed pumps (RFP's) in BWR plants, This system consists of a master level controller and sub-loop flow controllers for each of the RFP's. Control characteristics of the 2-loop control system were investigated using a dynamic analysis code for the condensate feedwater system.
Although the RFP system has a hydraulic coupling effect, the flow control loops become stable by setting adequate controller gains in the sub-loop flow controllers. The control characteristics in the major loop were modified in their initial response to level setpoint change by using a lead/lag compensator. Moreover, reactor core cooling was protected sufficiently during the transient in a trip of a turbine driven RFP. From simulation results of the transfer controls from the motor driven RFP to turbine driven RFP, it was ascertained that the 2-loop control system has such advantages as shorter completion time and superior controllability against ON-OFF action of a RFP recirculation valve during transfer control.
