Control of sucker rod pumps energy consumption

Sucker rod pump units are the primary means of mechanized borehole oil production worldwide. Difficult economic conditions, volatile oil prices and the continued growth of electricity tariffs forced oil producers to develop and implement energy-saving technologies. It is known that the most energy-intensive process at the oil companies is a well mechanized production. The technological process of lifting well fluid is accompanied by loss of energy in the following structural elements: a pump, plunger pair, valve assemblies, rod string, pumping unit, gearbox, motor, control station. The authors have developed a method of determining the relative energy consumption of sucker rod pump units. Pumping unit consumes from electric motor effective power required to lift well fluid. The losses in the motor are determined by efficiency and power factor. The exact definition of the loss in the motor is a difficult task due to the cyclic nature of the load. Cyclical nature of the load is taken into account by using the shape factor, which is determined by wattmetercard. The main factors affecting the relative power consumption are balanced pumping unit, density and water content of oil, stroke length and frequency of oscillation balance bar. The authors investigated the dependence of power downhole pumping units from oil properties: density and water content. Graphic dependence of the energy consumption of sucker rod pump units on the density and water content well fluid were built. The authors developed a model of the relative energy consumption of sucker rod pumps. The model consists of the subsystems of the effective mechanical power, of the motor efficiency at a given load, the power consumed from the electrical network, taking into account the balance of the pumping unit, the theoretical flow rate, taking into account practical flow rates of depression, productivity, skin-factor and permeability. The developed methodology and model the relative power consumption to be introduced in the software of intelligent control stations for oilwell pumps.