Design of aeration control system based on two degrees of freedom

Aiming to solve the problems of large nonlinear error, serious time lag, severe time-varying, multiple influencing parameters, and severe random interference in dissolved oxygen concentration control of sewage treatment systems, a control method based on two degrees of freedom is proposed by combining the advantages of two degrees of freedom, internal model control, and cascade PID control. This method effectively improves the problem of imprecise mathematical expressions in the aeration system and blower, which makes it difficult for other methods to achieve good control effects. The experimental results prove that the system has advantages such as outstanding adaptability, good tracking performance, significant control effect, and good robustness.