Research and application of electric power diagram to estimate dynamic liquid level in rod-pumping wells

The dynamic fluid level data of oil wells reflect the liquid supply and energy status of formations.The conventional manual regular testing method has problems such as untimely recording, poor continuity and poor real-time performance. By determining the quantitative indicators of electric power diagrams, a mathematical fluid level calculation model based on incremental upstroke electric power is established and solved, the influence of surface and underground equipment on the calculation results is eliminated, and a new method for calculating and collecting fluid level of oil wells has been developed. The field application of 9 wells shows that the average error of the algorithm is 5.82%, and the calculation accuracy is increased by 3.4%after considering casing pressure correction. The real-time tracking analysis of oil well's fluid surface is realized, which provides a simple and feasible method for the continuous monitoring of reservoir pressure.