Sophisticated software for design and optimization of variable speed drives for high-power pumps: Hydrodynamic coupling versus frequency converter

This paper deals with an analysis and comparison of high-power pump systems with flow control based on variable speed drives (VSDs). The attention is focused on a comparison of two advanced variable speed control strategies employing VSD with frequency converter and VSD with hydrodynamic coupling. Due to a very different nature of both drives it is a challenging task to compare them to each other, especially, in the area where a tiny efficiency improvement causes substantial energy consumption and/or CO2 emission reduction. The paper presents comparison of both VSDs in typical fields of their application (power plant, heating plant) in the form of case study. The calculations were performed using the software which we have developed for design, optimization and sophisticated comparison of these drives. Description of physical background of modeling and proposed models is also included.