Presenter/Author Information

G. Fu
David Butler
Soon-Thiam Khu

Keywords

evolutionary algorithms, integrated control, multi-objective optimization, nsga ii, urban wastewater system

Start Date

1-7-2008 12:00 AM

Abstract

In recent years much attention has been paid to integrated management and control of urban wastewater systems. With the application of integrated system modelling tools, overall system performance can be improved to a great extent in terms of receiving water quality, through development of optimal control strategies. Most studies to date, however, have used a single objective to demonstrate the potential benefits. Control of urban wastewater systems is actually a multiple objective optimisation problem, involving balancing different, possibly conflicting objectives required by stakeholders with different interests. This paper compares three different control strategies for multi-objective optimal control of the urban wastewater system, including one global control strategy and two integrated control strategies. A popular multiple objective evolutionary algorithm, NSGA II, is applied to derive the Pareto optimal solutions for the three strategies. The comparative results show the benefits of application of integrated control in achieving an improved system performance in terms of dissolved oxygen and ammonium concentrations in the receiving river. The simulation results also illustrate the effectiveness of NSGA II in deriving the optimal control strategies with different complexities.

COinS
 
Jul 1st, 12:00 AM

Comparison of control strategies for multiobjective control of urban wastewater systems

In recent years much attention has been paid to integrated management and control of urban wastewater systems. With the application of integrated system modelling tools, overall system performance can be improved to a great extent in terms of receiving water quality, through development of optimal control strategies. Most studies to date, however, have used a single objective to demonstrate the potential benefits. Control of urban wastewater systems is actually a multiple objective optimisation problem, involving balancing different, possibly conflicting objectives required by stakeholders with different interests. This paper compares three different control strategies for multi-objective optimal control of the urban wastewater system, including one global control strategy and two integrated control strategies. A popular multiple objective evolutionary algorithm, NSGA II, is applied to derive the Pareto optimal solutions for the three strategies. The comparative results show the benefits of application of integrated control in achieving an improved system performance in terms of dissolved oxygen and ammonium concentrations in the receiving river. The simulation results also illustrate the effectiveness of NSGA II in deriving the optimal control strategies with different complexities.