Monitoring system for accurate coalbed methane drainage

In view of problems existing in conventional coalbed methane drainage system, such as low control accuracy, high labor intensity, inability to operate according to drainage and extraction rules, and high production cost, a monitoring system for accurate coalbed methane drainage was designed. The system uses STM32F107 Connectivity series microcontrollers as the control center, and adopts field acquisition units to collect real-time downhole flow pressure, temperature, casing pressure value, frequency and other signals, and transmits the signals to the control center through RS485 communication interface and 4-20 mA analog interface. The deviation signal is obtained by comparing the measured value of downhole flow pressure with the given value. According to the deviation signal, the control center controls the output frequency of the converter in real time through the drainage control algorithm, and then adjusts the operation speed of the drainage equipment to realize the automatic closed-loop control of downhole flow pressure. 4G wireless transmission module is used to send control and adjustment command to drainage control unit to realize real-time monitoring and control of the drainage process. The field test results show that the system can execute the operation according to the real-time scheduling system, the regulation of downhole flow pressure is accurate, the average error is within 0.5%, which can meet the requirements of accurate coalbed methane drainage.