| Sucker rod pump units are widely used in oil extraction in our country. However, due to limitations of devices and technologies, most sucker rod pumps run under low efficiency in oilfield. Therefore, there is important practical significance to establish a laboratory simulation test rig for sucker rod pump units. As a new way of rod pump lifting, hydraulic lift technology applies the principle of hydraulic transmission and overcomes many disadvantages compared to traditional beam-lift method. It is able to realize stepless adjustment of parameters and has good adaptability for variety of oil well conditions. Therefore, the development electro-hydraulic proportional lift system (EHPLS) for simulation test rig of rod pump units (STRRPU), not only provides conditions for carrying out the study of rod pump units, but also paves way for the development of hydraulic lift pumping units.The EHPLS for STRRPU is researched in this paper. With electro-hydraulic proportional technology and computer control system (CCS), the EHPLS is capable of driving rod pump units performing simulation under variety of conditions (different angles, strokes and frequencies). The main thesis reads as follows:In chapter 1, the basic concepts and working principle of the rod pumping equipment are briefly introduced. The experimental study on rod pump units and the development of hydraulic lift technology, home and abroad, are summarized. And the purpose of research project and design content are proposed.In chapter 2, the functional requirements and targets parameters are formed, and the overall design scheme of EHPLS is put forward. Then, the overall design scheme is introduced in detail in five parts, including load balance designing, lifting approach designing, stroke-frequency curve planning, functional modules division, and overall layout.In chapter 3, the hydraulic system of EHPLS is designed. The working principle of the hydraulic circuit is discussed. The hydraulic system, including hydraulic implement system, counterweight system, power source system, valves system and auxiliary system, is calculated and designed. Products selections are conducted due to the parameter calculation and structural design. The 3D models of the hydraulic components in the system are all built in SolidWorks and virtual assembly is conducted.In chapter 4, the hardware and software of computer control system (CCS) for EHPLS are developed. The hardware composition and detailed realization of the data acquisition(DAQ) are introduced. Under the main framework of control system software, programs of various functional modules are coded in LabVIEW. Furthermore, the man-machine interface design of software is introduced.In chapter 5, design and implementation of controller are conducted. EHPLS simulation model is built and analyzed in AMESim. For turning closed-loop position control method to real controller, the incremental digital PID regulator and the median proportional valve dead-zone compensation algorithm are designed.In chapter 6, experiments under different conditions are carried out and test data is analyzed and studied.In chapter 7, some conclusions are given and the future work is put forward.
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