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Using the curve moment and the PSO-SVM method to diagnose downhole conditions of a sucker rod pumping unit 被引量:25
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作者 Li Kun Gao Xianwen +1 位作者 Tian Zhongda Qiu Zhixue 《Petroleum Science》 SCIE CAS CSCD 2013年第1期73-80,共8页
Downhole working conditions of sucker rod pumping wells are automatically identified on a computer from the analysis of dynamometer cards. In this process, extraction of feature parameters and pattern classification a... Downhole working conditions of sucker rod pumping wells are automatically identified on a computer from the analysis of dynamometer cards. In this process, extraction of feature parameters and pattern classification are two key steps. The dynamometer card is firstly divided into four parts which include different production information according to the "four point method" used in actual oilfield production, and then the moment invariants for pattern recognition are extracted. An improved support vector machine (SVM) method is used for pattern classification whose error penalty parameter C and kernel function parameter g are optimally chosen by the particle swarm optimization (PSO) algorithm. The simulation results show the method proposed in this paper has good classification results. 展开更多
关键词 Sucker rod pumping unit diagnosis of downhole conditions dynamometer card curvemoment support vector machine particle swarm optimization
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Design and Operation of Municipal Rain and Sewage United Pumping Station
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作者 Ting Ting Liu 《Journal of Architectural Research and Development》 2023年第4期51-56,共6页
In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifica... In the process of designing a municipal rainwater and sewage pumping station,it is necessary to accurately grasp the design points,reasonably determine the scale of the rainwater and sewage pumping station,scientifically select the location and layout,and select materials reasonably.After completing the process design of the municipal rainwater and sewage pumping station and putting it into operation,in order to ensure the normal and stable operation of the pumping station,it is necessary to focus on strengthening the operation and management of diving equipment,cleaning equipment,and electromechanical equipment.The author analyzes the key points and specific design path of the process design of municipal rainwater and sewage pumping stations,and puts forward effective strategies for operation management,hoping to contribute to the scientific design and stable operation of municipal rainwater and sewage pumping stations. 展开更多
关键词 Municipal administration Rainwater and sewage united pumping stations Design path Operation management
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Research on an Intelligent Decision Support System for a Conceptual Innovation Design of Pumping Units Based on TRIZ 被引量:1
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作者 Zhang Peng He Chuan Guan Hongxiang Gai Feng Qi Bin 《Petroleum Science》 SCIE CAS CSCD 2006年第1期85-91,共7页
Attention is concentrated on how to perform the innovative design during the process of pumping unit conceptual design, and how to enhance design efficiency and inspire creativity. Aiming at the shortages of conceptua... Attention is concentrated on how to perform the innovative design during the process of pumping unit conceptual design, and how to enhance design efficiency and inspire creativity. Aiming at the shortages of conceptual design, introducing the theory of inventive problem solving (TRIZ) into the mechanical product design for producing innovative ideas, and using the advanced computer-aided technique, the intelligent decision support system (IDSS) based on TRIZ (TRIZ-IDSS) has been constructed. The construction method, system structure, conceptual production, decisionmaking and evaluation of the problem solving subsystem are discussed. The innovative conceptual design of pumping units indicates that the system can help the engineers open up a new space of thinking, overcome the thinking inertia, and put forward innovative design concepts. This system also can offer the scientific instructions for the innovative design of mechanical products. 展开更多
关键词 pumping units innovative conceptual design TRIZ intelligent decision support system
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Research on Operation of Electrothermal Integrated Energy System Including Heat Pump and Thermal Storage Units Based on Capacity Planning
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作者 Taihong Liu Dingchen Wu +4 位作者 Fei Xu Panpan Song Mingshan Wei Jian Wu Xiaochun Bai 《Energy Engineering》 EI 2021年第3期535-548,共14页
In view of the Three North areas existing wind power absorption and environment pollution problems,the previous scholars have improved the wind abandon problem by adding electrothermal coupling equipment or optimizing... In view of the Three North areas existing wind power absorption and environment pollution problems,the previous scholars have improved the wind abandon problem by adding electrothermal coupling equipment or optimizing power grid operation.In this paper,an electrothermal integrated energy system including heat pump and thermal storage units was proposed.The scheduling model was based on the load data and the output characteristics of power units,each power unit capacity was programmed without constraints,and the proposed scheduling model was compared with the traditional combined heat and power scheduling model.Results showed that the investment and pollutant discharge of the system was reduced respectively.Wind power was fully absorbed.Compared with the traditional thermal power unit,the proportion of the output was significantly decreased by the proposed model.The proposed system could provide a new prospect for wind power absorption and environment protection. 展开更多
关键词 Electrothermal integrated energy system capacity planning thermal storage unit heat pump
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基于Unity3D的油田抽油机三维可视化监控系统设计 被引量:2
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作者 刘立强 孙文磊 +1 位作者 王一 王炳楷 《系统仿真学报》 CAS CSCD 北大核心 2024年第2期463-475,共13页
针对抽油机监测形式单一、三维可视化程度低和联动性差的缺陷,引入信息―物理实时映射思想,开发了油田抽油机三维可视化监控系统。设计了抽油机数字空间,搭建虚实交互层设计架构;搭建三维可视化系统数据组成及关系框架;结合逆运动学,构... 针对抽油机监测形式单一、三维可视化程度低和联动性差的缺陷,引入信息―物理实时映射思想,开发了油田抽油机三维可视化监控系统。设计了抽油机数字空间,搭建虚实交互层设计架构;搭建三维可视化系统数据组成及关系框架;结合逆运动学,构建数学模型,基于五维模型和Unity 3D平台设计抽油机三维可视化系统总体架构;以游梁式抽油机为对象进行实验验证,实现了实时动态监测、虚实混合控制、运动轨迹追踪和在线预警等服务功能。为三维可视化监控在石油机械领域的落地应用和数字孪生系统的开发提供借鉴。 展开更多
关键词 抽油机 三维可视化 实时动态监测 虚实混合控制 unitY3D
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Study on Dynamic Characteristics of Hydraulic Pumping Unit on Offshore Platform 被引量:5
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作者 CHANG Zong-yu YU Yan-qun QI Yao-guang 《China Ocean Engineering》 SCIE EI CSCD 2017年第6期693-699,共7页
A new technology of offshore oil rod pumping production is developed for offshore heavy oil recovery. A new type of miniature hydraulic pumping unit with long-stroke, low pumping speed and compact structure is designe... A new technology of offshore oil rod pumping production is developed for offshore heavy oil recovery. A new type of miniature hydraulic pumping unit with long-stroke, low pumping speed and compact structure is designed based on the spatial characteristics of offshore platforms. By combining the strengths of sinusoidal velocity curve and trapezoidal velocity curve, a kinematical model of the acceleration, the velocity and displacement of the pumping unit's hanging point is established. The results show that the pumping unit has good kinematic characteristics of smooth motion and small dynamic load. The multi-degree-of-freedom dynamic model of the single-well pumping unit is established. The first and second order natural frequencies of the sucker rod string subsystem and the pumping unit subsystem are studied. The results show that the first and the second order natural frequencies among the pumping rod string, pumping unit-platform subsystem and the dynamic excitation have differences over 5 times from each other, indicating that resonance phenomenon will not appear during the operation and the dynamic requirements for field use are met in the system. 展开更多
关键词 offshore platform platform pumping unit kinematic model dynamic model multiple degrees of freedom
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Prevention of stress-related ulcer bleeding at the intensive care unit: Risks and benefits of stress ulcer prophylaxis 被引量:24
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作者 Lukas Buendgens Alexander Koch Frank Tacke 《World Journal of Critical Care Medicine》 2016年第1期57-64,共8页
Stress-related mucosal disease is a typical complication of critically ill patients in the intensive care unit(ICU). It poses a risk of clinically relevant upper gastrointestinal(GI) bleeding. Therefore, stress ulcer ... Stress-related mucosal disease is a typical complication of critically ill patients in the intensive care unit(ICU). It poses a risk of clinically relevant upper gastrointestinal(GI) bleeding. Therefore, stress ulcer prophylaxis(SUP)is recommended in high-risk patients, especially those mechanically ventilated > 48 h and those with a manifest coagulopathy. Proton pump inhibitors(PPI) and, less effectively, histamine 2 receptor antagonists(H2RA) prevent GI bleeding in critically ill patients in the ICU. However, the routine use of pharmacological SUP does not reduce overall mortality in ICU patients. Moreover, recent studies revealed that SUP in the ICU might be associated with potential harm such as an increased risk of infectious complications, especially nosocomial pneumonia and Clostridium difficile-associated diarrhea. Additionally, special populations such as patients with liver cirrhosis may even have an increased mortality rate if treated with PPI. Likewise, PPI can be toxic for both the liver and the bone marrow, and some PPI show clinically relevant interactions with important other drugs like clopidogrel. Therefore, the agent of choice, the specific balance of risks and benefits for individual patients as well as the possible dose of PPI has to be chosen carefully. Alternatives to PPI prophylaxis include H2 RA and/or sucralfate. Instead of routine SUP, further trials should investigate risk-adjusted algorithms, balancing benefits and threats of SUP medication in the ICU. 展开更多
关键词 Proton pump inhibitors CLOSTRIDIUM DIFFICILE Intensive care unit Gastrointestinal HEMORRHAGE Stress HISTAMINE H2 ANTAGONISTS Risk assessment Pneumonia Physiological Sucralfate
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The Conceptual Design Method for a Pumping Unit Based on QFD and TRIZ 被引量:4
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作者 Zhang Peng Gai Feng Guan Hongxiang Li Ping 《Petroleum Science》 SCIE CAS CSCD 2005年第4期77-82,共6页
Quality function deployment (QFD) is a quality system, that can help to design novel products that meet customers' needs. Theory of inventive problem solving (TRIZ) is a very powerful tool in helping to solve dif... Quality function deployment (QFD) is a quality system, that can help to design novel products that meet customers' needs. Theory of inventive problem solving (TRIZ) is a very powerful tool in helping to solve difficult technical problems encountered in the design process. Introducing QFD and TRIZ into the conceptual design of the pumping unit combines advantages of these two theories, therefore meeting different demands of different users. It can tell us “What should we do it” with QFD and “How should we do it” with TRIZ. The conceptual design method, which is based on QFD and TRIZ, is introduced andused to analyze and evaluate the conceptual design project of a pumping unit. 展开更多
关键词 pumping unit quality function deployment (QFD) theory of inventive problem solving (TRIZ) conceptual design method
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Design of the Control System of Adaptive Balancing Device Based on PLC 被引量:5
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作者 Sha Zhu Yuexiang Li +1 位作者 Yu Wang Yonghui Wang 《Intelligent Control and Automation》 2015年第3期200-204,共5页
Due to the well condition and the un-expected imbalance movement of the pumping unit in use, the energy consumes a lot. The existing balancing equipment cannot adjust and monitor the pumping units in real time. Theref... Due to the well condition and the un-expected imbalance movement of the pumping unit in use, the energy consumes a lot. The existing balancing equipment cannot adjust and monitor the pumping units in real time. Therefore this paper introduces the new adaptive balancing equipment—fan-shaped adaptive balancing intelligent device, projects a design of such control system based on PLC, and determines the principle of the control system, the execution software and the design flow. Site commissioning effect on Daqing Oilfield shows this fan-shaped adaptive balancing intelligent device can effectively adjust and monitor the pumping unit in real time, the balance even adjusts from 0.787 to 0.901, and integrated energy saving rate is 14.2%. It is approved that this control device is professionally designed, with strong compatibility, and high reliability. 展开更多
关键词 pumping unit Fan-Shaped ADAPTIVE Balancing Intelligent DEVICE BALANCE Adjustment Energy SAVING PLC Remote Control
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IMPROVE THE KINETIC PERFORMANCE OF THE PUMP CONTROLLED CLAMPING UNIT IN PLASTIC INJECTION MOLDING MACHINE WITH ADAPTIVE CONTROL STRATEGY 被引量:3
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作者 QUAN Long LIU Shiping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第1期9-13,共5页
The kinetic characteristics of the clamping unit of plastic injection molding machine that is controlled by close loop with newly developed double speed variable pump unit are investigated. Considering the wide variat... The kinetic characteristics of the clamping unit of plastic injection molding machine that is controlled by close loop with newly developed double speed variable pump unit are investigated. Considering the wide variation of the cylinder equivalent mass caused by the transmission ratio of clamping unit and the severe instantaneous impact force acted on the cylinder during the mold closing and opening process, an adaptive control principle of parameter and structure is proposed to improve its kinetic performance. The adaptive correlation between the acceleration feedback gain and the variable mass is derived. The pressure differential feedback is introduced to improve the dynamic performance in the case of small inertia and heavy impact load. The adaptation of sum pressure to load is used to reduce the energy loss of the system. The research results are verified by the simulation and experiment, The investigation method and the conclusions are also suitable for the differential cylinder system controlled by the traditional servo pump unit. 展开更多
关键词 Adaptive control Pump controlled system Clamping unit Plastic injection molding machine
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Thermodynamic Simulation of CCP in Air-Cooled Heat Pump Unit with HFCs and CO<sub>2</sub>Trans-Critical 被引量:2
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作者 Feihu Chen Shuguang Liao Guangcai Gong 《Journal of Power and Energy Engineering》 2018年第9期141-164,共24页
The exergy analysis and finite time thermodynamic methods had been employed to analyze the compound condensation process (CCP). It was based on the air-cooling heat pump unit. The cooling capacity of the chiller unit ... The exergy analysis and finite time thermodynamic methods had been employed to analyze the compound condensation process (CCP). It was based on the air-cooling heat pump unit. The cooling capacity of the chiller unit is about 1 kW, and the work refrigerant is R22/R407C/R410A/CO2. The MATLAB/SIMULINK software was employed to build the simulation model. The thermodynamic simulation model is significant for the optimization of parameters of the unit, such as condensation and evaporation temperature and mass flow of the sanitary hot water and size of hot water storage tank. The COP of the CCP of R410A system is about 3% - 5% higher than the CCP of the R22 system, while CCP of the R407C system is a little lower than the CCP of R22 system. And the CCP of CO2 trans-critical system has advantage in the hot supply mode. The simulation method provided a theoretical reference for developing the production of CCP with substitute refrigerant R407C/R410A/CO2. 展开更多
关键词 Air-Cooled Heat Pump unit Compound Condensation Process (CCP) Exergy Analysis Method Sanitary Hot Water MATLAB/SIMULINK Software Fluorine SUBSTITUTE REFRIGERANT R407C/R410A Natural REFRIGERANT CO2
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SIMULATION IN THERMAL DESIGN FOR ELECTRONIC CONTROL UNIT OF ELECTRONIC UNIT PUMP 被引量:1
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作者 XU Quankui ZHU Keqing ZHUO Bin MAO Xiaojian WANG Junxi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第5期1-7,共7页
The high working junction temperature of power component is the most common reason of its failure. So the thermal design is of vital importance in electronic control unit (ECU) design. By means of circuit simulation... The high working junction temperature of power component is the most common reason of its failure. So the thermal design is of vital importance in electronic control unit (ECU) design. By means of circuit simulation, the thermal design of ECU for electronic unit pump (EUP) fuel system is applied. The power dissipation model of each power component in the ECU is created and simulated. According to the analyses of simulation results, the factors which affect the power dissipation of components are analyzed. Then the ways for reducing the power dissipation of power components are carried out. The power dissipation of power components at different engine state is calculated and analyzed. The maximal power dissipation of each power component in all possible engine state is also carried out based on these simulations. A cooling system is designed based on these studies. The tests show that the maximum total power dissipation of ECU drops from 43.2 W to 33.84 W after these simulations and optimizations. These applications of simulations in thermal design of ECU can greatly increase the quality of the design, save the design cost and shorten design time 展开更多
关键词 Diesel engine Electronic unit pump Electronic control unit Circuit simulation thermal design
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MODEL-BASED DEVELOPMENT OF REAL-TIME SOFTWARE SYSTEM FOR ELECTRONIC UNIT PUMP SYSTEM 被引量:1
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作者 YU Shitao YANG Shiwei YANG Lin GONG Yuanming ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期25-30,共6页
A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-base... A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased. 展开更多
关键词 Real-time operating system (RTOS) Multi-task V-model development Hardware-in-the-loop simulation system(HILSS) Electronic unit pump (EUP)
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Evaluation of Appropriateness of Proton Pump Inhibitors (PPIs) Use in the Region of Sharjah, United Arab Emirates (UAE)
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作者 Osama H. Mohamed Ibrahim Mohamed E. A. Rashrash +3 位作者 Rand Albasha Reem Alani Sama Khadhum Sameh Soliman 《Pharmacology & Pharmacy》 2018年第6期149-156,共8页
Background: Proton pump inhibitors (PPIs) are drugs that reduce the production of acid in the stomach. Recently, the use of PPI has been increasing among communities, whether with or without prescription. As a part of... Background: Proton pump inhibitors (PPIs) are drugs that reduce the production of acid in the stomach. Recently, the use of PPI has been increasing among communities, whether with or without prescription. As a part of the healthcare team, the pharmacist should not only dispense medications but also ensure the appropriate use of these medications. Studies conducted within 16 countries showed substantial variation in the appropriateness of the use of PPI drugs. Aim: To evaluate the appropriateness of PPIs use in Sharjah, UAE based on surveys answered by pharmacists, physicians, and patients. Methods: A cross-sectional survey study was conducted on December 2017 at Sharjah, UAE as an example of information obtained from the Middle East. Two different surveys were conducted on physicians and pharmacists. Both Physicians and Pharmacists were chosen randomly from Yellow Pages. The results obtained from both studies were used to develop a patient’s survey, which was distributed among University of Sharjah students, their families and random people at Shopping Malls and Clinics. Results: The results obtained from the patients’ survey showed that ~39% of PPI users from the region of Sharjah are 25 - 44 years old. Approximately 79% are using PPI according to physicians’ prescriptions. Prescriptions’ duration is varied between 1 month (39%) and 6 months (22%), where 52% of PPI users ask their physicians to prescribe PPIs when needed. Suggested reasons for the use of PPI included inappropriate food habits (52%), use of other medications (16%) or bacterial infection (13%). Around 52% of the patients did not receive any recommendations regarding the deprescribing of PPIs. According to the pharmacists’ surveys, an average sale of 5 - 10 PPI packages is reported per day, and around 50% are sold without a prescription. Most pharmacists were not fully aware of the health conditions and side effects of PPI drugs. On the other hand, physicians’ surveys showed that PPIs were mainly prescribed in the case of GERD and ulcer and for a maximum of 2 - 4 weeks. Approximately 75% of physicians recommend changing regimen by reducing the dose and stopping in case of chronic use of PPIs. Conclusion: The results from this survey study indicated that even though most PPI consumers at Sharjah, UAE are well aware of the use of PPI drugs and they follow the instructions given by the Physicians’, there is some discrepancy in the information obtained by the physicians, pharmacists, and patients. The reason for this discrepancy may be attributed to the missing role of the pharmacists which is currently just dispensing the medications without appropriate counseling. Thus the appropriate role of the pharmacists should be implemented according to the known international guidelines. 展开更多
关键词 Proton Pump Inhibitors Deprescribing APPROPRIATE USE unitED Arab Emirates (UAE)
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A research on an energy-saving software for pumping units based on FNN intelligent control
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作者 丁宝 齐维贵 王凤平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期240-244,共5页
An energy-saving scheme for pumping units via intermission start-stop performance is proposed. Because of the complexity of the oil extraction process, Fuzzy Neural Network (FNN) intelligent control is adopted. The st... An energy-saving scheme for pumping units via intermission start-stop performance is proposed. Because of the complexity of the oil extraction process, Fuzzy Neural Network (FNN) intelligent control is adopted. The structure of the Takagi-Sugeno (T-S) fuzzy neural network model is introduced and modified. FNNs are trained with sample information from oil fields and expert knowledge. Finally, pumping unit energy-saving FNN software, which cuts down power costs substantially, is presented. 展开更多
关键词 rocker pumping unit T-S fuzzy system fuzzy neural network BP algorithm
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Optimum Structural Design of a Chain-Driving Pumping Unit
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作者 Zhang Ailin and Liu Yang(Doctors,Qinhuangdao Branch of Daqing Petroleum Institute) 《China Oil & Gas》 CAS 1994年第4期45-47,共3页
In this paper the pumping unit of type QLCJ14-6 is studied.Through the belt driving unit,the mo-tor drives the driving sprocket in which the rotation rate has been reduced by the reduction ge arbox.The locus chain mov... In this paper the pumping unit of type QLCJ14-6 is studied.Through the belt driving unit,the mo-tor drives the driving sprocket in which the rotation rate has been reduced by the reduction ge arbox.The locus chain moves between the driving sprocket and upper sprocket which are vertically set.There's a special chain element in the locus chain,which drives the reciprocating holster with the main shaft linchpin and slide block.The r reciprocating g holster could only move up and down when the locus chain moves in a circle.In this way the up and down stroke of the sucker rod and the mac hine is realized.The lower end of the reciprocating holster is con-nected with the equilibrium system to make the structure balance.The balancing cylinder is re-placed by the balancing block to make the structure simplified. 展开更多
关键词 CHAIN DRIVE pumping unit STRUCTURAL design Optimization
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Performance Analysis of a Six-bar Linkage Pumping Unit Based on a Small Fluctuations Load Shape
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作者 REN Tao SUN Wen 《International Journal of Plant Engineering and Management》 2010年第3期157-163,共7页
Crank shaft net torque of pumping units is a volatile alternating load, while output torque of a general motor is basically constant. Thus, load characteristics of pumping units and motors are not able to "harmoniou... Crank shaft net torque of pumping units is a volatile alternating load, while output torque of a general motor is basically constant. Thus, load characteristics of pumping units and motors are not able to "harmoniously" match each other; this resulted in a higher output of the motor, lower efficiency, and higher energy consumption of the pumping units. A new six-bar linkage pumping unit is presented according to moment-changing theory. It allows to adjust automatically following the changes of polished rod load, and achieves small crank shaft curve fluctuation. The new pumping unit improves motor efficiency, reduces motor output power, and saves energy. According to the design scheme, kinematics and kinetics models of the new six-bar linkages pumping unit are built up. An optimum design on the main peoCormance parameters and functional analysis were peoCormed. 展开更多
关键词 six-bar linkage pumping unit performance analysis optimization design energy saving
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Wind Turbine Speed Compound Control of a New-Type Wind-Electric Hybrid Power Pumping Unit
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作者 Chunyou ZHANG Lihua WANG 《Mechanical Engineering Science》 2020年第2期15-24,I0005,共11页
Because the load of the oil beam pumping unit driven by pure electric motor changes sharply during operation,the power of the driving motor does not match and the energy efficiency is low.In this paper,a new type of w... Because the load of the oil beam pumping unit driven by pure electric motor changes sharply during operation,the power of the driving motor does not match and the energy efficiency is low.In this paper,a new type of wind-driven hydro-motor hybrid power system is proposed.The motor and the hydraulic motor are jointly driven,and the energy is recovered by a hydraulic pump with controllable displacement,so that the speed of the driving motor is relatively stable.In order to control the fan speed and keep up with the drastic changes of the outside wind speed,a control strategy of hybrid power system based on wind speed feed-forward compensation is proposed.Through simulation and experimental results,the following conclusions can be drawn:to begin with,the mathematic model is proved to be effective;next,simulation studies show that the proposed feed-forward control method can improve the response rate as well as reduce the response lag.This research can be a reference for the application of the feed-forward control method on the hybrid power system of beam pumping unit.system. 展开更多
关键词 beam pumping unit hydraulic-motor hybrid system feed-forward control method Fuzzy-PID control
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Novel Neural Network Inspired by Neuro-Endocrine-Immune System with Its Application to Beam Pumping Unit
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作者 刘宝 段慧 +1 位作者 康忠健 薄迎春 《Journal of Donghua University(English Edition)》 EI CAS 2016年第5期719-723,共5页
Inspired by the modulation mechanism of neuroendocrine-immune system(NEIs),a novel structure of artificial neural network(ANN) named NEI-NN and its learning method are presented.The NEI-NN includes two parts,i.e.,posi... Inspired by the modulation mechanism of neuroendocrine-immune system(NEIs),a novel structure of artificial neural network(ANN) named NEI-NN and its learning method are presented.The NEI-NN includes two parts,i.e.,positive subnetwork(PSN) and negative sub-network(NSN).The neuron functions of PSN and NSN are designed according to the increased and decreased secretion functions of hormone,respectively.In order to make the novel neural network learn quickly,the novel neuron based on some characteristics of NEIs is also redesigned.Besides the normal input signals,two control signals are considered in the proposed solution.One is the enable/disable signal,and the other is the slope control signal.The former can modify the structure of NEI-NN,and the later can regulate the evolutionary speed of NEINN.The NEI-NN can obtain the optimized network structure by using error back-propagation(BP) learning algorithm.Since the modeling of the beam pumping unit is very difficult by using the conventional method,the modeling of bean bump unit is chosen to examine the performance of the NEI-NN.The experiment results show that the optimized structure and learning speed of NEI-NN are better than those of the conventional neural network. 展开更多
关键词 Immune enable quickly pumping directional Endocrine chosen hidden neuroendocrine secretion
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Parallel Operation Characteristics Analysis of Sewage Source Heat Pump Units in Winter 被引量:2
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作者 庄兆意 张承虎 +1 位作者 王海燕 孙德兴 《Transactions of Tianjin University》 EI CAS 2010年第6期461-466,共6页
Sewage source heat pump unit operates under partial load most of the time, and study on the law of coefficient of performance (COP) of the unit varying with load ratio can provide basis for the heat pump units running... Sewage source heat pump unit operates under partial load most of the time, and study on the law of coefficient of performance (COP) of the unit varying with load ratio can provide basis for the heat pump units running in high efficiency. A mathematical model determining COP, evaporation temperature and condensation temperature of a single unit was proposed. Under the condition of uniform load distribution, the model was established according to different ways of bearing partial load with the same type multi... 展开更多
关键词 sewage source heat pump unit coefficient of performance (COP) partial load parallel operation
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