Research And Design Of Intelligent Downhole Flow Controller Hydraulic Monitoring System

Intelligent well technology is a new oil well production management system,which is an important part of intelligent digital oilfield.In recent years,with the continuous improvement of oil and gas exploitation technology in China,and the implement of the exploitation strategy of beach,deep sea and other mining strategies,the oil and gas production has been increasing year by year.Intelligent well has attracted more and more attention due to its intelligent detection,remote control and production capacity optimization.The downhole flow controller is the core component of intelligent well.By giving different pressure signals of the flow control valve in the surface hydraulic system,the throttling control of the valve body to the productive layer can be realized.In this paper,a set of hydraulic monitoring system which can provide pressure source to downhole flow controller of intelligent well and its supporting data monitoring scheme are designedFirst of all,on the basis of analyzing the present situation and development trend of hydraulic control system of intelligent well flow controller at home and abroad,aiming at the functional requirements and practical difficulties of the system,the paper proposes a three-layer architecture including the bottom layer data collection,ground control system and upper computer HMI software monitor.On the basis of the design of the whole system frame,the key technology of the system implementation is summarized and introduced.Then,the multi-node data acquisition algorithm and asynchronous motor control algorithm involved in the system are studied deeply.In the field of hydraulic control system,there are many data acquisition nodes and various data fonnats,so it is necessary to study the corresponding data format encapsulation and acquisition algorithm.In this context,a multi-node encapsulation and acquisition algorithm for CAN data is proposed.The algorithm can transform,identify and transmit the underlying multi-data nodes.The pressure source of hydraulic system comes from the motor pump of the system.The pressurization time from the motor pump to the pipeline is determined by the speed of the asynchronous motor.In order to realize the frequency conversion speed control of the motor,the PID control of the motor Algorithm is designed.In order to realize the simulation of asynchronous motor,the mathematical model of nonlinear asynchronous motor is established in MATLAB Simulink,the control operator of PID is designed,and the optimal control parameters are determined by comparing the simulatioin results of many groups.Finally,on the basis of the above research,the ground core control system of the hydraulic system of the intelligent well flow controller based on PLC and the corresponding HMI monitoring software of the upper computer are developed,and the test bench is made according to the design sample.The test results show that the system can realize the intelligent control of hydraulic system,can meet the supply demand of different pressure of flow controller in intelligent well,and the matching hydraulic decoder can complete the throttling control function of multi-layer and multiple opening degree.The scheme is reasonable and practical.