Paper: Using ESPs with Variable Frequency Drives to Perform Well Tests on Multiple Lateral Horizontal Producing Wells In The 4-Corners Area

This paper describes the use of electrical submersible pumping systems (ESP"s) with portable variable frequency drives (VFD"s) to perform step-rate testing on multi lateral horizontal producing oil wells in the 4 - Corners area of New Mexico, Colorado, Utah, and Arizona. A major Operator drilled and completed several of these multi lateral wells in the area. High volume ESP's were installed due to the success of the multi lateral concept and resultant high producing rates. Down hole sensors were installed to monitor drawdowns and changes in reservoir pressure and temperature as the step-rate tests were performed. Surface measurements of fluid producing rates, well head pressures, and VFD parameters were also made, and were communicated to the Operator via SCADA systems and cellular phone links. The units were initially started at low frequencies on the VFD"s, and the rates and pressures monitored until stable. Then the VFD was sped up, with new rates and pressures measured. The process was repeated in several steps until the well either pumped off or became gas locked. This paper presents the results of these operations and illustrates with schematics, system drawings, and production decline rates how the wells performed and how the well testing program was successful.