Development Of Low-power Pressure Recorder With Bluetooth For Urban Natural Gas Pipeline

With the construction and improvement of urban natural gas pipe network,more and more residents use natural gas.In order to ensure the quality and safety of residential gas,natural gas companies monitor and record the pressure of natural gas pipelines.Natural gas is a flammable gas,so there are special requirements for pressure recording equipment.At present,pressure recorder used in natural gas pipeline mainly reads data through U disk.However,using U disk to read data is not convenient and the working efficiency is low.When reading and writing the U disk,the working current is large and the reading and writing speed is slow,resulting in high power consumption of the system.Data files can only be viewed using dedicated PC software.To solve the above problems,this thesis proposes a scheme of replacing USB interface with Bluetooth Low Energy,reading data with mobile phone,and realizing data transmission in short distance.According to this scheme,a low-power pressure recorder with Bluetooth has been designed and realized.The recorder has functions such as pressure measurement,data storage,Bluetooth communication,and human-computer interaction.At the same time,the mobile APP was developed to realize the functions of reading data via Bluetooth and viewing data files.The main problem of this scheme is how to realize Bluetooth communication.This design refers to the Bluetooth solution of the wearable device.The main control chip selects PSoC with integrated BLE module.Make full use of the on-chip resources of PSoC to improve system integration and performance.The system is powered by the ER26500 lithium battery and is designed with low power consumption.The pressure measuring circuit adopts the diffused silicon pressure core supplied by the constant voltage source and the high performance instrument amplifier.The pressure value is calculated by six-point calibration and piecewise linearization,to ensure the measuring accuracy of the Bluetooth pressure recorder.The recorder adopts the rolling storage scheme,and the 128 KB data storage space can store up to 65,536 points of pressure data.Finally,the system is tested in the laboratory environment.The measurement accuracy of the Bluetooth pressure recorder reaches 0.5 level at room temperature.The average transmission rate of Bluetooth communication can reach 8.5KB/s,and the entire reading can be completed in 20 seconds.The recorder has a standby current of approximately 0.04 mA,a maximum current of 1.85 mA during measurement,and a maximum current of 11.39 mA during Bluetooth communication.The lithium battery can be used for more than 3 years at a sampling frequency of 10 seconds.The test results show that the recorder meets the requirements of technical indicators,is convenient to use,and has high production efficiency,which greatly improves the user experience.