Efficiency improvement of water-pumping systems based on field-oriented speed control of IM drive

The conventional pumping systems, using mechanical methods, suffer from energy loss during the process of varying head or/and water flow. This paper presents a technique for controlling the water head and flow based on system demands with energy save and maximum efficiency. This technique is based on field oriented speed control of induction motor (IM) for driving the pumping system. The energy is saved by moving the operating point of pump-motor system from an initial operation to a point at which the required head and flow are achieved. That point is located at a new performance curve which relates to the requested flow and head. Unlike the conventional methods, the drawn power by pump-motor drives is just enough for that movement without an excessive flow or/and head possibility. The control method is verified by simulation results and the performance of the system is studied at different requirements. From the results, the system efficiency could be increased and then energy could be saved.