Study And Design Of Fuel Gas Compressor Control System Based On PLC

The fuel gas-compressor machine is the key equipment of natural gas processing plant.It is used as asource of refrigeration to extract the ethane and natural gas liquids from natural gas.At the same time itproduces energy to drive the compressor which compresses the processed sale gas to a higher pressure fortransferring to the customer.In normal condition,the yield of propane production is about to95%.the fuelgas compressor machine is a mechanism that always works in the extremity of high rotor speed,pressureand gas flow.the auxiliary system and control device are very complicated.And in process industry,if such akey unit as fuel gas compressor emergency shutdown,it will cause a huge lost.So the Fuel gas compressormachine requests high performance of instrument control system.How to make the instrument controlsystem not only with highly reliability，stability,sensitivity but also with convenience to operation andmaintenance is always a difficult question for engineers and technicians.This dissertation paper takes the fuel gas compressor maehine of wenchang13-1/2oilfield plant as astudy objeet.According to the control specification of fuel gas compressor and serious analyzing of thefunction and control logic as wellthe field operating procedures of fuel gas compressor machine SLC SeriesPLC control system from Allen-Bradley company is taken to implement the proeess contro1and emergenceshutdown system.At the field site,there is a PANEL MATE1175touch serene to be the Human MachineInterface (HMI).PLC are well adapted to arrange of automation control tasks and havethe facility forextensive input/output arrangement.All contro1strategy can be expressed to make logic in simple ladderlogic which appears similar to eleetrical schematic diagrams.It is easily accomplished the control functionby using ladder logic so that it will reduce training cost of technicians.Because PLC are designed forimmunity to electrical noise,and resistance to vibration and impact,it has a great ability to ensure the safetyand stability of mechanism running.