Extending Pump Unit Service Life Using Combined Pump Control

The paper describes the implementation of a combined pump control strategy in order to increase its reliability and service life. With the help of combined control, the flow rate is controlled simultaneously by rotational speed variation, throttling, and bypass. The energy consumption of the pump unit is evaluated, and the reliability of its operation is examined according to three various flow rate control methods that are applied: with minimum energy consumption, with maximum reliability (service life), and a method that provides a trade-off between energy consumption and service life. Comparison of energy consumption in the considered cases shows that with the trade-off regulation method, energy consumption is 6.36% higher than with the help of the minimum energy consumption control. However, the combined control method allows achieving significant energy savings up to (20.6%) in comparison with the maximum reliability control method.