Dynamic delayed controllers for recycling systems with internal delays and complex poles

Recycling systems are a challenging problem from the control viewpoint due to their detrimental effects. This paper proposes a simple way to stabilize and control a class of high-order recycling systems with time delays, internal instability, and possible complex conjugate poles. The strategy proposes P/PI/PD/PID-like delayed controllers. Conditions to guarantee the stability of the controlled closed-loop system are stated. The performance of the proposed delayed controllers is illustrated via numerical simulations of a high-order unstable recycling system and an industrial chemical process.

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