الفهرس 
Description of Water Pump-Motor Drive SystemOnly 14 pages are availabe for public view
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Abstract
The growing energy market and increasing energy costs require new solutions in pumping technology aiming to rise the energy efficiency. The traditional pump speed regulation method suffers from high energy loss during the process of varying head or/and water flow. This thesis suggests a technique for controlling the water head and flow by controlling motor speed in order to save energy and maximize efficiency. The proposed technique is based on field oriented speed control of induction motor (IM) that drives the pump. As a result, the system performance can be kept within the best efficiency region at all requested flow and head inputs. Moreover, energy is saved by moving the operating point of pump-motor system from an initial operation to more efficient point at which the required head and flow are achieved. That point is located at a new performance curve corresponding to the requested flow and head. Unlike the conventional methods, the power drawn by pump-motor drives is just enough for that movement without an excessive flow or/and head. The system performance is studied at three operating conditions of head and flow requirements. The control method is verified by simulation results in both steady state and dynamic conditions.
An experimental setup has been implemented based on DSPACE/CLP1104 in order to verify the vector control of induction motor under speed control based on the system required flow and head. This setup consists of the 0.37kW induction motor, three phase two level voltage source inverter, three phase rectifier 30A, DC link capacitor, three current sensor LA25-NP- 25A, incremental Encoder 500 pulses and variable power supply. The experimental results of the speed control at different loading conditions are presented. The study has been extended to multi-pump systems. Two variable speed drive strategies are adopted for driving these systems. The first one is multi-pump single drive (MPSD) in which only one pump is controlled while the others are operated at rated condition. In the second strategy, all pumps are controlled to achieve required flow so it is called multi-pump multi drive (MPMD). A comparison between the two strategies have been performed with the aid of simulation results. The overall system efficiency of the two strategies is analyzed for four case studies. from the results, the system efficiency could be improved and more energy could be saved when using MPMD system. Moreover, MPMD is economically more feasible. The cost of the drive system could be paid back within three years while its life time is more than ten years. Moreover, MPMD is more reliable and requires less maintenance than MPSD.