Research On Variable Speed Operation And Energy Saving Mechanism Of Pumping Unit

Beam pumping unit has been the most important mechanical oil production mode frombirth due to its safe and reliable, sturdy and durable, wide adaptability and other excellentcharacteristics. However, as the beam pumping unit has inherent structure characteristics,when it’s in constant speed driving, suspension point and gearbox can be subjected to theintense periodical alternating load impact. In order to achieve the purpose of load shedding,consumption reduction and increase production, all the oil fields both at home and abroadcarry out the research on driving pumping technology of dynamic variable optimization. Butthe theory model of variable speed operation optimization technology is not perfect, theenergy-saving mechanism is not clear, there are some adverse effects in the application suchas: the overload of the gear box, Therefore, it is necessary to study the control strategy andenergy saving mechanism of variable speed operation optimization.The pumping unit kinematics model and the calculation methods of suspension pointload were established based on kinematics and working characteristic analysis of pumpingunit four bar mechanism. The power saving rate of pumping unit system is regarded as theoptimization goal, the motor, gear box and rod non-overloading are constraint condition, thevariable speed operation curve was confirmed according to the combination of theory andexperiment method, a set of variable speed optimization operation strategy and forecastcalculation method is put forward, and compile a set of variable speed optimization designprogram of pumping unit well system.In order to improve the transmission efficiency computational accuracy of eachtransmission part of the pumping unit, according to the indoor motor test platform andpumping unit outdoor test platform, the instantaneous torque and rotate speed of pumping unittransmission parts were tested, and fitting the efficiency formula of motor, belt, gear box andfour connecting rod. Variable speed optimization operation control technology has been smallscope applied in Daqing oilfield, according to the tested data analysis of10oil wells showsthat: the average comprehensive power saving rate is15.843%after enforcement measures,the gear box peak torque average reduction rate is16.04%, the system efficiency increased by2.883%.The pumping unit well system dynamics variable speed drive run through theoptimization method. It can realize the goal of load reduction, energy saving and improvemechanical extraction system working conditions under meeting the pumping unit operationsafety and reliability. The research results for promoting the development of pumping unitvariable speed operation coupling dynamics theory has great significance. It laid a theoryfoundation and scientific basis for oil field mechanical oil extraction system realizing loadshedding and energy saving.