Beam Pumping Unit Dynamic Modeling And Control Based On The Mechanism Analysis

Beam pumping unit is the most common rob oil machine which is used in many oilfields because it has simple structure, can accommodate bad weather outdoors, and easy to maintain and can work for a long time. But there still exists two disadvantages on large energy consumption and low efficiency, which are not solved effectively up to now. Whether replacing the oil by water or electricity can lead to energy dissipation. So it is very important to research energy saving of beam pumping unit.The paper analyzes motion characteristics of beam pumping unit, does accurate analysis about its four bar mechanism and conducts simulation research. On that basis, equivalent moment and equivalent moment of inertia of beam pumping unit are calculated combining dynamic and static load of suspension point, crank torque and so on. Dynamically equivalent model of the system is obtained. On the electrical platform of Schneider, speeds control of beam pumping unit experimental facility is realized through Unity Pro software, PLC and frequency converter. The relationship between fluid production, peak load at suspension point, output power of electric motor and frequency converter is analyzed. Energy efficiency program of controlling motor speed through pump depth ratio to do dynamic feedback is designed. Proceeding soft start and stepless speed regulation of electric motor via frequency converter can protect the motor and extend its operating life. It can realize PID control of speed and operator screen configuration in Unity Pro. Combining human-computer interface software Vijeo Designer, configuration of touch panel picture can be realized. By means of downloading projects to a single or multi object machine, we can operate on the touch panel directly, which is very convenient.The experiment makes full use of facilities in Schneider Electrical laboratory, and realize interactive communication between upper computer, PLC, frequency converter and touch panel through Ethernet connection. Combining beam pumping unit experimental facility, the paper makes some research and experimental control about energy conservation problems.