Simulation and PID Control of Bullwhip Effect in Closed-Loop Supply Chain based on Noise Bandwidth

In order to describe quantitatively and control effectively the bullwhip effect in closed-loop supply chain, modeling and analysis method of control theory was applied to establish z-domain model of single-echelon closed-loop supply chain. By z-transform, the discrete transfer function was constructed. And based on noise bandwidth of the transfer function between demand and order, the bullwhip effect of closed- loop supply chain was quantified and analyzed. By designing Genetic Algorithm (GA), tuning control parameters in Proportion-Integral-Differential (PID) controller were obtained. Thus, PID controller was designed in order to control the bullwhip effect. Simulation results indicated the designed PID controller can eliminate effectively the bullwhip effect of closed-loop supply chain.