OPTIMIZED PUMP SCHEDULING IN WATER DISTRIBUTION-SYSTEMS

A method based on nonlinear programming for determining the optimal op eration of general water distribution systems containing multiple sour ces and reservoirs is presented. The problem is formulated and solved so that, given the forecasted demands for the coming 24 hours, the ini tial and final conditions in the reservoirs, the unit and maximum dema nd electricity charge, and the constraints in the hydraulic properties of all system components, an optimized pumping schedule is found. An optimization algorithm which employs the generalized reduced gradient method and the nonlinear sensitivity analysis has been developed for a basic scheduling problem in which only unit charges are considered. T he maximum demand charge, which is weighted by varying degrees from da y to day, is incorporated into the scheduling problem. The algorithm u ses a feasible initial solution as the starting solution and iterates so that all the interim solutions are feasible.