One of the world’s leaders in oil production used low-voltage motor starters and step-up transformers to operate medium-voltage electric submersible pumps that were located more than 3,000 meters below the surface. This method met minimum requirements for pumping oil but did not optimise oil production or reduce energy consumption.
One of their goals is to apply technology in a cost-effective way to increase efficiency and improve safety. As a result, they sought out a more productive and efficient way to operate the pumps.
Since the submersible pumps are medium-voltage pumps, mediumvoltage drives could have been utilized. However one of the priorities was to minimize maintenance costs. Low-voltage drives and step-up transformers were selected to keep maintenance costs to a minimum.
Danfoss VLT drives, along with the available Programmable Motion Controller (MCO305) option meet the requirements of a submersible pump application. The Programmable Motion Controller option provides the intelligence required to self-regulate the pumps, eliminating the need for an external PLC. In addition, Danfoss’ proven sensorless control and reputation for quality and reliability contributed to the decision to use Danfoss VLT drives.
The pumps in these applications range in size from 45 kW to over 200 kW (60 HP – 300 HP) with larger applications anticipated in the future. The voltage of the pumps range from 2400 volts to 7200 volts. The flexibility of the step-up application is ideally suited for these applications because the step-up transformer can be specified with any output voltage.
