Dredge Pumping Systems Improve with VFD Motor Controls
Submitted by Dave Stoltenberg, Dredge Rental Specialist, SRS Crisafulli
Pumps and Systems recently published an article by Christopher Jaszczolt titled “VFDs Improve Motor and Pump Control”. The article discussed current applications of variable frequency driven (VFD) motor controls as an excellent method to improve on mechanical control methods. VFD control systems have gained market share and visibility in the past decade as an excellent motor control methodology with the added benefit of energy conservation. By implementing VFD controls on dredge pumps, dredges become much more usable with the typical slower processing speeds of dewatering systems.
Jaszczolt says: ”Preferably, some of the pumps can be shut down when demand is low, and the system can be designed so that the water pressure can be maintained by a single pump during periods of low demand. Properly designed lead-lag systems will improve the efficiency, performance and longevity of the pumping system.”
Jaszczolt also tells us: “Like a PLC—advanced VFDs can be programmed, monitored and maintained with PC-based software. Unlike a PLC, this software is generally provided free by the VFD supplier. VFD programming and monitoring software is also easier to use than similar software for PLCs because the software is for a single application specific rather than general purpose.
VFDs have been used to control pumps for many years. However, advanced pump-specific VFDs now allow users to improve motor/pump control and protection without the need for inefficient mechanical devices or costly PLCs.”
Christopher Jaszczolt is an application engineer with the Drives and Motion Division of Yaskawa America, Inc., in Waukegan, Ill. He has a BSEE from Northern Illinois University and five years’ experience applying variable frequency drives in industrial applications.