基于PLC的液压无杆排采系统研究

Hydraulic rodless drainage system based on PLC

针对目前煤层气无杆排采过程中工作人员劳动强度大、设备工作效率低、控制精度差等问题,设计了新型液压驱动无杆泵,并基于PLC设计了控制系统。所设计的控制系统可通过压力计,对井下流压进行实时测量,并将测量值反馈到PLC中,与设定值进行比较运算;基于比较运算结果,通过变频器完成了电机转速实时调控,进而实现了井底流压的动态调整;无杆泵由三通道油管内置动力液管加压后提供驱动力,在驱动力作用下往复运动,实现了阀体间自动上下切换,有效降低了工作人员劳动强度。试验结果表明:该系统可根据设定值对井底流压进行快速、精准调整,且超调量较小。

Aiming at the problems of high labor intensity of staff, low efficiency of equipment and poor control precision in rodless drainage of coalbed methane, a new type of hydraulic driven rodless pump was designed, and the control system was designed based on PLC. The designed control system measured the bottom hole flow pressure in real time by pressure gauge, and feed the measured value back to the PLC to compare with the set value. Based on the results of the comparison calculation, the motor speed was adjusted in real time by frequency converter ,and then the bottom hole flow pressure was adjusted dynamically. The rodless pump was driven by a three-channel tubing with a power hydraulic pipe pressurized and reciprocates under the driving force. Motion, to achieve automatic up and down switching between the valve body, effectively reduced the labor intensity of staff. The test results show that the system can adjust the bottom hole flowing pressure quickly and accurately according to the set value, and has a small overshoot.