New parameter tuning method of washout filter-aided controller for dynamic behavior adjustment

Bifurcation diagrams of open loop and closed loop systems of anaerobic fermentation of 1,3-propanediol. In the open loop system, the optimal operating point is on the unstable branch. After introducing washout filter-aided controller with appropriate controller parameters tuned by the proposed method, a Hopf point appears near the optimal operating point. The original unstable equilibrium manifold between the Hopf point and limit point is stabilized without changing the shape of the equilibrium manifold.