Comparison of various control techniques for motor-pump sets applied in selected water distribution systems

The water distribution system applied in the thermal-electric power station EC Tychy SA is analyzed. The economical aspects of various control techniques for motor-pump sets in the aforementioned system are presented in the paper on the example of pumps working out of the cold season. The reasons of control losses occurring in the present system are depicted. The way of improvement of control effectiveness is proposed but unprofitability of the investment is also shown. A control of pumps by throttling and control by rotational speed changes are compared in the paper. It is shown that control by rotational speed changes causes similar losses like control by throttling if application of variable-speed technique is not preceded by appropriate adaptation of water distribution system, especially by adjustment of pump rated parameters.