Application of a new Smith Fuzzy PID in electric boiler temperature control system

摘要

Since the object model is time-varying and time-delay in the electric boiler temperature control system, Smith Fuzzy PID controller is applied in it. Simulation results in the paper show that the overshoot is reduced by 31.3% compared with the system under Smith PID control and the adjusting time reached a 30% reduction compared with those under Fuzzy PID control with T=380 and τ=110. In order to eliminate the oscillation problem in system when model parameters change, a new Smith Fuzzy PID controller with two degrees of freedom is applied, whose control performance is much better than that of Smith Fuzzy PID.