Model Predictive Control of Overflow in Sewer Networks: A comparison of two methods

In this work, a comparison of two previous proposed methods for Model Predictive Control (MPC) of sewage systems are presented. The focus is on prediction of overflow from weirs and the computation time of the methods. The first method considered in this study is a mixed integer quadratic program MPC based on mixed linear dynamic formulations. The second method considered is a quadratic program MPC with optimizable overflows and accumulated overflow volume penalty. For the comparisons of the methods, a case study of the Barcelona sewer network is utilized. Our numerical experiments show that the predictions of the system’s experienced overflow, performed by the quadratic program MPC are equivalent to the predictions of the mixed integer variant, but is computing faster and in general reduces the overflow volumes, due to the difference in the choice of control.