Beam Pumping with Variable Speed Drives- Past, Present and Future

Variable speed drives have changed the way beam pumping units keep wells pumped down, prevent failures, and extend the life of the machine. VSDs, although slow to be accepted are now a typical portion of the control mechanism found in pumping units. In this paper, we will review the history of VSDs in the oilfield, provide an overview of where they are now an take a glimpse into the near future of developments. We will also cover issues that VSDs bring into the field with power quality concerns such as additional harmonics and what new technologies are available now and in the near future to combat these power quality issues.