Practical Model for Energy Consumption Analysis of Beam Pumping Motor Systems and Its Energy-Saving Applications

Due to the dynamic load and the complex mechanical link, it is difficult to precisely analyze the characteristics of the energy consumption of beam pumping motor systems (BPMSs) in the development of energy-saving approaches in oil production systems. To solve this problem, this paper establishes a practical model that combines the standard differential equation of an induction motor, the crank movement equation and the wave equation of sucker rod, the loss equations of the low- and high-voltage supply lines, and distribution transformers for energy consumption analysis of BPMSs. With this practical model, the influence of different factors, including the load fluctuation, balance degree, and dynamic liquid levels, on the electrical loss characteristics of BPMSs can be analyzed. The variation of the electrical loss in a Type-12 BPMS driven by a 37-kW induction motor with different dynamic liquid levels and balance degrees is studied, and the distribution characteristic of each loss component under five typical load conditions in oil field is also analyzed. It is revealed that the proportion of iron loss is about 40% of the total electrical loss. The correctness of the model is verified by comparing the calculated results with the measured data for a standard oil well. In addition, the energy-saving devices based on the theoretical results obtained by the presented model achieve a significant energy-saving ratio in the practical application at oil fields.