Performance Improvement of Pumps Fed by the Variable Speed Drives

Abstract

-Speed inaccuracy decreases the pump efficiency, reliability, and energy saving. This research is devoted to the determination of the ways of accurate speed control of the pump drives operated under changeable loads. The impact of speed inaccuracy on the pump performance is studied. Based on the analysis of methods for the static accuracy improvement, the drawbacks of the traditional approaches have been shown with reference to the pumping applications. A new methodology of the slip compensation has been proposed for implementation to improve the scalar drive performance. It notably decreases the speed inaccuracy of the open-ended pumping applications. The enhanced quality of the drive control at different loading conditions has been shown on a laboratory test bench. Also, for the multi-pump systems this approach results in an additional benefit from the viewpoint of the operation around the best operation point providing a safe pump control both to exclude the pump damage and to improve the process quality.

PLC-based hardware-in-the-loop simulator of a centrifugal pump

“…To validate the model, an experimental test bench has been used based on Ebara CDX 120/12 pumps driven by ACQ810 VSDs [24], [25]. In the functional diagram in Fig.…”

Analytical determination of speed-torque and speed-current curves of single-cage induction motor under supply voltage and frequency variations

“…Only one of the required parameters like the break-down torque can be easily taken from the manufacturer catalog data, while the unknown break-down slip can be roughly evaluated from the given rated torque and rated speed of the motors (Buksnaitis, 2011;Emde et al, 2014;Ivanov and Ushakov, 2007;Kral et al, 2009). The Kloss formula is commonly used in different kinds of controls (Imecs, 2009;Jardan et al, 2011;Kodkin et al, 2014;Reljic et al, 2006;Shawinski, 2010;Vodovozov and Bakman, 2013) and analysis (Anass et al, 2009;Bollen, 1995;Das, 1990;Sumper et al, 2010). For example, from the control perspective, the formula can be directly applied for estimating the motor's speed when the torque is given, as it provides a quick and accurate (in the linear region) torque prediction at any arbitrary speed (Imecs, 2009;Kodkin et al, 2014;Reljic et al, 2006;Vodovozov and Bakman, 2013).…”

“…The Kloss formula is commonly used in different kinds of controls (Imecs, 2009;Jardan et al, 2011;Kodkin et al, 2014;Reljic et al, 2006;Shawinski, 2010;Vodovozov and Bakman, 2013) and analysis (Anass et al, 2009;Bollen, 1995;Das, 1990;Sumper et al, 2010). For example, from the control perspective, the formula can be directly applied for estimating the motor's speed when the torque is given, as it provides a quick and accurate (in the linear region) torque prediction at any arbitrary speed (Imecs, 2009;Kodkin et al, 2014;Reljic et al, 2006;Vodovozov and Bakman, 2013). The Kloss formula can be also used for stability analysis of induction motors (Anass et al, 2009;Bollen, 1995;Das, 1990;Sumper et al, 2010).…”

PLC-Based Pressure Control in Multi-Pump Applications

“…To explore different system curves, the operator can change the pipe cross-sectional area using a discharge valve. Detailed description of the composition of the experimental setup can be found in [23].…”