| The paper uses special wireless digital technology and GPRS network data transmission technology to complete oil pumping unit's current signal and the voltage signal wireless transmission. A complete set of wireless transceiver system of current and pressure are designed and producted which provides the theory and technology support for the process of digital oilfield production technology.The design accomplishes current detection system, pressure test system and portable handheld recorder system hardware circuit,which includes the circuit principle diagram design, PCB design and PCB soldering and debugging. Three systems'software program, download, debugging and modification are also completed. Analog signals of current and pressure convert to digital signals and computation, storage and read of digital value are accomplished. The paper determines conversion coefficient of current and pressure'decimal values and the coefficient can be adjusted and calibrated. According to the actual needs of users,we can switch to the corresponding send mode. In portable recorders receiving mode,the LCD recorder system displays current and pressure datas that are five figure, and the decimal is one bit.So software program must judge correctly the decimal place and save the data.The working principle of resistance strain gauge is analysised to determine mathematical formula of pressure size and resistance changes. The working principle of single bridge circuit, the electric resistance changes bridge legs and the mathematical expression of the output voltage of bridge, programmable integrated operational amplifier'magnification is determined in the SCM. Wireless transceiver chip nRF24L01's software control is finished,including work mode, the channel number, sending a packet and receiving packets format.We hnow well standby wireless transceiver chip PTR2000's working principles,and master its control principles.The PTR2000 can replace nRF24L01 to work under special circumstances. To design recorder system keyboard circuit, to determine key functions and to complete keyboard circuit software scanning.To operate skillfully LCD display HTG240160C and to complete the display of Chinese character, characters, numbers and graphics. To achieve calendars of real-time display clocks of recorder system and calendar clock can be calibrated through the keyboard.To complete USB data transmission's the software design of the display screen of recorder system.To understand GPRS networks technology's working principle, features and application.To be familiar with GPRS online process of GPRS module SIM300. To design GPRS networks Sending mode's flow of current and pressure datas. To achieve data transmission of current detection system and pressure test system in the laboratory and the data receiving experiment of portable recorders system.To record the data of experiment and analysis the data.Contrasting the actual transmission of data to the theoretical data to find the shortage of the hardware and software and improve the reliability and stability of the system. |
