Linear Oil Production Motor Control And Downhole Multi-parameter Monitoring

Linear oil production motor system is an important oil production equipment in the middle and late stage of oilfield development.Compared with the traditional submersible electric pump system,it has the advantages of higher efficiency and lower energy consumption.The linear oil production motor system is an oil production system that directly drives the double-acting reciprocating pump to lift the well fluid through the submersible linear motor.The control strategy of linear oil production motor is an important part of oilfield production.The matching downhole multi-parameter monitoring system is called ’ oil production partner ’.This paper studies these aspects.Firstly,the structure and operation principle of the linear oil production motor system and the control circuit of the linear motor are analyzed.A control strategy of adaptive stroke adjustment is proposed.The strategy adjusts the number of strokes of the linear motor according to the storage capacity of the oil well fluid.Reasonable use of capacity resources,reduce labor costs and equipment maintenance costs,and can make oilfield production in the best state.Secondly,the designed downhole multiparameter monitoring system includes two parts : the downhole data acquisition system and the ground data processing system.The artificial star point is formed by the threephase reactor on the ground and the three-phase winding of the downhole linear motor relies on the principle of star point equipotential to supply power to the downhole system.The downhole data acquisition system collects downhole temperature,pressure,and motor vibration parameters.After the time-sharing gating circuit,it is transmitted to the ground system in the form of 4-20 m A current through the metal sheath of the submersible cable in a set order.The current signal passes through the precision sampling resistor,and the voltage at both ends of the sampling resistor is collected by the AD acquisition module.It is transmitted to the ground data processing part with STM32F103ZET6 as the main control chip.After data processing,the data is stored and displayed.The ground part also developed the power supply system,and designed a double self-locking switch device to improve the stability and safety of the system power supply.On the basis of the above work,the downhole simulation test was carried out in the laboratory,the test parameters were changed,the corresponding data were recorded and analyzed,the feasibility of the sensor was verified,the fitting curve was obtained,and the reference current was measured.The parameters of the fitting curve and the calibration method of the reference current are input into the ground data processing software design part to obtain the actual value measured by the sensor.Finally,through the system joint debugging test,the feasibility and stability of the underground multiparameter monitoring system are verified.