The object of temperature control for low-pressure bypass has features of large amplitude and fast speed for parameter's variation

hence

enhancement of the rapidity in response of control system

the stability in regulation

and the accuracy in control

to ensure safety of the main equipment is a problem to be solved in the temperature control system of low-pressure by-pass.Based on analysing several typical control strategies

two optimized schemes have been put forward

i.e.a closed-loop feedback control scheme using simple feedward signal and automatic setting

and a closed-loop feedback control scheme using accurate feedward and automatic setting.Comparision between two said schemes shows that the first scheme can be used under condition without flow rate signal of desuperheating water;while the second scheme has accurate theoritical calclation

boasting correction function of the closed-loop control

and having the highest control accuracy.