Design And Implementation Of RTU Measurement And Control System For Oil Pumping Unit

With the development of the embedded technology,RTU has been a key equipment for constructing an intelligent oil/gas well,which has been widely used in management and production on oil/gas field and made full use of important action.To solve the problems of the existing RTU functions such as not strong scalability and poor scalability,this theme developed and designed an RTU measurement and control system for pumping units.By analyzing the advantages and disadvantages of the existing remote monitoring system for oil and gas wells and combining the actual needs of the pumping unit data acquisition system,a solution of the miniaturized and cost-effective RTU measurement and control system for a pumping unit is proposed.The system can realize multi-parameter and multi-channel data acquisition,and has certain anti-interference and function expansibility.The RTU is oriented to the oil/gas well,which realizes the collection and transmission of field equipment operating parameters,and remotely controls the function of the wellsite equipment.In view of the development and design of RTU measurement and control system for pumping units,the major study context in this paper includes:(1)In the aspect of the design of the hardware platform,the RTU for the pumping unit,which selected STM32F429 as the main control processor the system,adopted a distributed structure sheme,the architecture of “core control board + function board”,is conducive to the expansion,development,and operational maintenance of the function,and is also convenient for user's application.The core control board integrates the smallest system,storage module(SDRAM+Flash+EEPROM),LCD expansion port,ATK interface and USB interface.The function motherboard has designed the power supply circuit,I/O port module,communication port module,SD card storage circuit and so on.The I/O port module includes 8 channels of digital input,8 channels of digital output,6 channels of analog input,and 2 channels of analog output.The communication port module is composed of RS-232/RS-485 serial communication,ZigBee wireless communication and Ethernet communication.In view of the function module circuit on the functional motherboard,a variety of isolation methods such as photoelectric isolation and magnetically coupled isolation have been adopted to improve the anti-interference ability of RTU and enhance the stability and reliability of RTU.(2)In the aspect of software design,the main program and various functional subprograms are designed based on the embedded real-time operating system of C/OS-III,including digital input task(Task_DI),analog input task(Task_AI),digital output task(Task_DO),analog input task(Task_AO)and serial communication task(Task_Com).(3)The schematic diagram of the RTU is drawn up,and the PCB is produced.The laboratory prototype of the RTU is welded and assembled,and some functions of the prototype are tested.To summarize,the feasibility of the design of the RTU measurement and control system for pumping units is verified finally,and the expected design goals are achieved.