METHOD OF HYDRODYNAMIC INVESTIGATIONS OF OIL WELLS EQUIPPED WITH ELECTRIC-CENTRIFUGAL PUMPS WITH CONVERTER OF CURRENT FREQUENCY Russian patent published in 2013 - IPC E21B47/00 E21B43/25 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to methods of hydrodynamic investigations of oil wells equipped with submersible electric-centrifugal pumps and control stations with frequency converters, and it may be used for choice of optimum operating mode of well. Method of hydrodynamic investigations of oil well involves connection of electric-centrifugal pump to production electric network through converter of frequency of current supplied to electric-centrifugal pump. Well flow rate is measured as per oil during operation in mode of rated power frequency. Depression is created by means of increase in electric-centrifugal pump efficiency due to increase in current frequency to the value providing steady mode of well operation under which well flow rate as per fluid is maximum. Well flow rate is measured as per fluid, also water content of its products is measured during operation in mode of rated frequency. When maximum value is reached current frequency is reduced to the value providing steady mode of well operation under which well flow rate as per fluid is minimum. Increase and reduction of current frequency is performed during continuous operation of electric-centrifugal pump with repeated measurement of pressure and temperature at pump suction, well flow rate and water content on wellhead. As per the measurements results curve is built for pressure recovery during transition of well operation mode at which well flow rate as per fluid is maximum to operation mode at which well flow rate as per fluid is minimum. Then hydro- and piezo-conductivity, permeability, supply contour radius, skin factor are determined. Also optimum frequency of current supplied to electric-centrifugal pump, under which reduction of water content and increase in flow rate as per oil relative to analogous values during well operation in mode of rated frequency is provided, is determined.

EFFECT: improving efficiency of determination of optimum mode of removals from formation under which product water content is reduced and flow rate as per oil relative to analogous values during well operation in mode of rated frequency increases.

3 cl, 9 dwg