Motor-ESP Characteristic-Integrated Energy Balance Method for Production Estimation

To address the challenges of high cost and poor real-time performance in traditional production measurement methods for electric submersible pump (ESP) wells, this study investigates an energy balance-based production estimation method utilizing motor and pump characteristics to enable timely monitoring of production trends. The methodology involves: 1) preliminary correction of pump characteristic curves considering fluid properties; 2) calculation of theoretical motor output power using surface current data combined with motor characteristic curves; 3) determination of actual output power corresponding to production rates from pump curves; 4) iterative refinement of production-power curves through differential analysis between theoretical and actual power values; 5) final determination of daily liquid production using averaged daily current data on calibrated curves.Implementation of this methodology in the Tarim Oilfield involved 493 validated well tests across 6 wells after invalid data elimination. Results demonstrate measurement errors ranging from 5.2% (minimum) to 24% (maximum), with an average error of 13.6%. These findings preliminarily verify the theoretical correlation between motor power, pump efficiency, and production parameters. Comparative analysis reveals superior technical performance over conventional methods, particularly in cost-effectiveness. Unlike traditional downhole capillary pressure measurement approaches, this method establishes differential pressure as a function of production rate and power, enabling flowrate calculation through Q-H-P relationship modeling.The proposed technique shows potential for replacing manual well testing and achieving continuous production monitoring through further optimization. This dual-capability solution offers significant cost reduction while maintaining enhanced measurement accuracy, representing a technological advancement in ESP well management. Key innovations include dynamic characteristic curve correction mechanisms and current-based power calculation algorithms, which effectively address historical limitations in real-time performance and operational costs associated with conventional measurement systems.