Sample records for hydraulic control systems

  1. Towards Autonomous Control of Hydraulic Actuator Systems

    Hansen, Poul Erik; Conrad, Finn


    Presentation of new developed control algorithms to increase autonomy and intelligence of hydraulic control systems. A refinement of relaytuning method is used to determine the control parameters of a lag/lead controller and a poleplacement controller. Further, a fail-safe function is developed...... to hinder surges and mechanical fractures. Experimental results verify the performance of the controllers....

  2. Underwater hydraulic shock shovel control system

    LIU He-ping; LUO A-ni; XIAO Hai-yan


    The control system determines the effectiveness of an underwater hydraulic shock shovel.This paper begins by analyzing the working principles of these shovels and explains the importance of their control systems.A new type of control system's mathematical model was built and analyzed according to those principles.Since the initial control system's response time could not fulfill the design requirements,a PID controller was added to the control system.System response time was still slower than required,so a neural network was added to nonlinearly regulate the proportional element,integral element and derivative element coefficients of the PID controller.After these improvements to the control system,system parameters fulfilled the design requirements.The working performance of electrically-controlled parts such as the rapidly moving high speed switch valve is largely determined by the control system. Normal control methods generally can't satisfy a shovel's requirements,so advanced and normal control methods were combined to improve the control system,bringing good results.

  3. Control Reconfigurability of Bilinear Hydraulic Drive Systems

    Shaker, Hamid Reza; Tahavori, Maryamsadat


    be effective if sufficient redundancy does not exist in the process. A measure for control reconfigurability which reveals the level of redundancy in connection with feedback control is proposed in this paper for bilinear systems. The proposed control reconfigurability measure is the extension of its gramian......The objective of the methods within the framework of the plug and play process control and particularly fault tolerant control is to establish control techniques which guarantee a certain performance through control reconfiguration at the occurrence of the faults or changes. These methods cannot......-based analogous counterpart, which has been previously proposed for the linear processes. The control reconfigurability is calculated for the bilinear models of an electro-hydraulic drive to show its relevance to redundant actuating capabilities in the models....

  4. Study on Characteristics of Hydraulic Servo System for Force Control of Hydraulic Robots

    Kim, Hyo-gon; Han, Changsoo [Hanyang University, Seoul (Korea, Republic of); Lee, Jong-won [Korea University of Science and Technology, Seoul (Korea, Republic of); Park, Sangdeok [Korea Institute of Industrial Technology, Seoul (Korea, Republic of)


    Because a hydraulic actuator has high power and force densities, this allows the weight of the robot's limbs to be reduced. This allows for good dynamic characteristics and high energy efficiency. Thus, hydraulic actuators are used in some exoskeleton robots and quadrupedal robots that require high torque. Force control is useful for robot compliance with a user or environment. However, force control of a hydraulic robot is difficult because a hydraulic servo system is highly nonlinear from a control perspective. In this study, a nonlinear model was used to develop a simulation program for a hydraulic servo system consisting of a servo valve, transmission lines, and a cylinder. The problems and considerations with regard to the force control performance for a hydraulic servo system were investigated. A force control method using the nonlinear model was proposed, and its effect was evaluated with the simulation program.

  5. Design of Transputer Controllers for Hydraulic Actuator Systems

    Conrad, Finn


    The paper deals with how transputers can be applied for fast controllers for hydraulic actuator systems. A general transputer-based control systems including a data acquisition transputer subsystem is presented. An application case: development of a mechatronic test facility with a fast hydraulic...

  6. Hydraulic drive and control system of the cone collecting robot

    Kong Qinghua; Liu Jinhao; Lu Huaimin


    This paper describes the basic structure and design and operation principle of the hydraulic drive and control system with two pumps and two circuits. The manipulator of the cone collecting robot designed is full driven by hydraulic, which has five freedoms. The computer and electrohydraulic proportion velocity regulating valve were installed to realize open loop serve control for reducing cost and easy application.

  7. A low order adaptive control scheme for hydraulic servo systems

    Andersen, Torben Ole; Pedersen, Henrik Clemmensen; Bech, Michael Møller;


    This paper deals with high-performance position control of hydraulics servo systems in general. The hydraulic servo system used is a two link robotic manipulator actuated by two hydraulic servo cylinders. A non-linear model of the hydraulic system and a Newton-Euler based model of the mechanical...... system were constructed and linearized. Controllers are implemented and tested on the manipulator. Pressure feedback was found to greatly improve system stability margins. Passive gain feedforward shows improved tracking performance for small changes in load pressure. For large changes in load pressure......, active gain feedforward shows a slightly improved performance. Computed-Torque Control shows better performance, but requires a well described system for best performance. A novel Adaptive Inverse Dynamics Controller was tested and the performance was found to be similar to that of Computed...

  8. Adaptive Non-linear Control of Hydraulic Actuator Systems

    Hansen, Poul Erik; Conrad, Finn


    Presentation of two new developed adaptive non-liner controllers for hydraulic actuator systems to give stable operation and improved performance.Results from the IMCIA project supported by the Danish Technical Research Council (STVF).......Presentation of two new developed adaptive non-liner controllers for hydraulic actuator systems to give stable operation and improved performance.Results from the IMCIA project supported by the Danish Technical Research Council (STVF)....

  9. Nonlinear control for a class of hydraulic servo system

    余宏; 冯正进; 王旭永


    The dynamics of hydraulic systems are highly nonlinear and the system may be subjected to non-smooth and discontinuous nonlinearities due to directional change of valve opening, friction, etc. Aside from the nonlinear nature of hydraulic dynamics, hydraulic servo systems also have large extent of model uncertainties. To address these challenging issues, a robust state-feedback controller is designed by employing backstepping design technique such that the system output tracks a given signal arbitrarily well, and all signals in the closed-loop system remain bounded. Moreover, a relevant disturbance attenuation inequality is satisfied by the closed-loop signals. Compared with previously proposed robust controllers, this paper's robust controller based on backstepping recursive design method is easier to design, and is more suitable for implementation.

  10. Nonlinear control for a class of hydraulic servo system

    余宏; 冯正进; 王旭永


    The dynamics of hydraulic systems are highly nonlinear and the system may be subjected to non-smooth and discontinuous nonlinearities due to directional change of valve opening,friction,etc. Aside from the nonlinear nature of hydraulic dynamics,hydraulic servo systems also have large extent of model uncertainties. To address these challenging issues,a robust state-feedback controller is designed by employing backstepping design technique such that the system output tracks a given signal arbitrarily well,and all signals in the closed-loop system remain bounded. Moreover,a relevant disturbance attenuation inequality is satisfied by the closed-loop signals. Compared with previously proposed robust controllers,this paper's robust controller based on backstepping recursive design method is easier to design,and is more suitable for implementation.

  11. International Space Station power module thermal control system hydraulic performance

    Goldberg, V. [Boeing North American, Inc., Canoga Park, CA (United States). Rocketdyne Div.


    The International Space Station (ISS) uses four photovoltaic power modules (PVMs) to provide electric power for the US On-Orbit Segment. The PVMs consist of photovoltaic arrays (PVAs), orbit replaceable units (ORUs), photovoltaic radiators (PVRs), and a thermal control system (TCS). The PVM TCS function is to maintain selected PVM components within their specified operating ranges. The TCS consists of the pump flow control subassembly (PFCS), piping system, including serpentine tubing for individual component heat exchangers, headers/manifolds, fluid disconnect couplings (FQDCs), and radiator (PVR). This paper describes the major design requirements for the TCS and the results of the system hydraulic performance predictions in regard to these requirements and system component sizing. The system performance assessments were conducted using the PVM TCS fluid network hydraulic model developed for predicting system/component pressure losses and flow distribution. Hardy-Cross method of iteration was used to model the fluid network configuration. Assessments of the system hydraulic performance were conducted based on an evaluation of uncertainties associated with the manufacturing and design tolerances. Based on results of the analysis, it was concluded that all design requirements regarding system performance could be met. The hydraulic performance range, enveloping possible system operating parameter variations was determined.


    Wei Jianhua; Kong Xiaowu; Qiu Minxiu; Wu Genmao


    The simulation model of a valve control hydraulic system with long pipe is established in Simulink4.0, and then the step responses of the systems with difference pipe parameters are investigated by simulation.Simulation results show that the long pipes will slow down the step response of system and make it fluctuate periodically.The results of simulation conform to the results of experiment on the whole, which proves the mathematic model is correct.


    Yang Jian; Xu Bing; Yang Huayong


    A robust control algorithm is proposed to focus on the non-linearity and parameters'uncertainties of an electro-hydraulic proportional speed control system (EHPSCS) with a single-rod hydraulic actuator. The robust controller proposed does not need to design stable compensator in advance, is simple in design and has large scope of uncertainty applications. The feedback gains of the robust controller proposed are small, so it is easily implemented in engineering applications.Experimental research on the speed control under the different conditions is carried out for an EHPSCS. Experimental results show that the robust controller proposed has better robustness subject to parametric uncertainties, and adaptability of parameters' variation of control system itself and plant parameter variation.

  14. Active control of multi-input hydraulic journal bearing system

    Chuang, Jen-Chen; Chen, Chi-Yin; Tu, Jia-Ying


    Because of the advantages of high accuracy, high capacity, and low friction, the development of hydrostatic bearing for machine tool receives significant attention in the last decades. The mechanics and mechanical design of hydrostatic journal bearing with capillary restrictors has been discussed in literature. However, pragmatically, the undesired loading effects of cutting force tend to result in resonance and instability of the rotor and damage the shaft during operation. Therefore, multi-input, active flow control using state feedback design is proposed in this paper. To this purpose, the proportional pressure valves are added to the hydraulic system as active control devices, and the linearised models of the bearing and valve are discussed and identified. Simulation and experimental work is conducted to verify the proposed active control and parameter identification techniques. The results show that the unbalance responses of the rotor are reduced by the proposed state feedback controller, which is able to regulate the flow pressure effectively, thus enhancing the stability and accuracy of the hydraulic journal bearing.

  15. Hydraulic engine valve actuation system including independent feedback control

    Marriott, Craig D


    A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

  16. Tap Water Hydraulic Control Systems - Design and Industrial Applications. Chapter 7 in Advances in Hydraulic Control Systems

    Conrad, Finn

    Deals with development and design of modern tap water hydraulic components and systems, in particalar the Danfoss Nessie-family of components and systems working with pure tap water without any kind of additives. Typical industrial applications are presented and the perspectives of new industrial...

  17. Nonlinear, Adaptive and Fault-tolerant Control for Electro-hydraulic Servo Systems

    Choux, Martin

    Fluid power systems have been in use since 1795 with the rst hydraulic press patented by Joseph Bramah and today form the basis of many industries. Electro hydraulic servo systems are uid power systems controlled in closed-loop. They transform reference input signals into a set of movements...... in hydraulic actuators (cylinders or motors) by the means of hydraulic uid under pressure. With the development of computing power and control techniques during the last few decades, they are used increasingly in many industrial elds which require high actuation forces within limited space. However, despite...... numerous attractive properties, hydraulic systems are always subject to potential leakages in their components, friction variation in their hydraulic actuators and deciency in their sensors. These violations of normal behaviour reduce the system performances and can lead to system failure...

  18. Contamination Control and Monitoring of Tap Water as Fluid in Industrial Tap Water Hydraulic Systems

    Conrad, Finn; Adelstorp, Anders


    Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems.......Presentation of results and methods addressed to contamination control and monitoring of tap water as fluid in tap water hydraulic systems....

  19. System and method for controlling hydraulic pressure in electro-hydraulic valve actuation systems

    Brennan, Daniel G; Marriott, Craig D; Cowgill, Joel; Wiles, Matthew A; Patton, Kenneth James


    A control system for an engine includes a first lift control module and a second lift control module. The first lift control module increases lift of M valves of the engine to a predetermined valve lift during a period before disabling or re-enabling N valves of the engine. The second lift control module decreases the lift of the M valves to a desired valve lift during a period after enabling or re-enabling the N valves of the engine, wherein N and M are integers greater than or equal to one.

  20. Active disturbance rejection control for hydraulic width control system for rough mill


    The highly nonlinear behavior of the system limits the performance of classical linear proportional and integral (PI) controllers used for hot rolling. An active disturbance rejection controller is proposed in this paper to deal with the nonlinear problem of hydraulic servo system in order to preserve fast response and small overshoot of control system. The active disturbance rejection (ADR) controller is composed of nonlinear tracking differentiator (TD), extended state observer (ESO) and nonlinear feedback (NF) law. An example of the hydraulic edger system case study is investigated to show the effectiveness and robustness of the proposed nonlinear controller, especially, in the circumstance of foreign disturbance and working condition variation,compared with classic PI controller.

  1. Evaluation of Linear and Non-Linear Control Schemes Applied to a Hydraulic Servo System

    Andersen, Torben Ole; Hansen, Michael Rygaard; Pedersen, Henrik Clemmensen


    Due to the innovation of low-cost electronics such as sensors, microcontrollers etc., the focus on highperformance motion control is increasing. This work focuses on position control of single-input single-output hydraulic servo-systems in general. A hydraulically actuated robotic manipulator...

  2. Use of single chip microcomputer in hydraulic digital adaptive control system


    Presents a one-grade adaptive controller with one reference model which is built according to δ MRACS adaptive control theorv and used to control an actual high-order hydraulic system, and the whole hard ware system used, which includes a AT89C51 single chip microcomputer, 74Ls373 flip-latch, 6116 store, eight-bit ADC0809, and so on, and the satisfactory results obtained in study on hydraulic control system.


    FENG Yonghui; ZHANG Jianwu


    Increase of elevator speed brings about amplified vibrations of high-speed elevator. In order to reduce the horizontal vibrations of high-speed elevator, a new type of hydraulic active guide roller system based on fuzzy logic controller is developed. First the working principle of the hydraulic guide system is introduced, then the dynamic model of the horizontal vibrations for elevator cage with active guide roller system and the mathematical model of the hydraulic system are given. A fuzzy logic controller for the hydraulic system is designed to control the hydraulic actuator. To improve the control performance, preview compensation for the controller is provided. Finally, simulation and experiments are executed to verify the hydraulic active guide roller system and the control strategy. Both the simulation and experimental results indicate that the hydraulic active guide roller system can reduce the horizontal vibrations of the elevator effectively and has better effects than the passive one, and the fuzzy logic controller with preview compensation can give superior control performance.

  4. Adaptive Control System of Hydraulic Pressure Based on The Mathematical Modeling

    Pilipenko, A. V.; Pilipenko, A. P.; Kanatnikov, N. V.


    In this paper, the authors highlight the problem of replacing an old heavy industrial equipment, and offer the replacement of obsolete control systems on the modern adaptive control system, which takes into account changes in the hydraulic system of the press and compensates them with a corrective action. The proposed system can reduce a water hammer and thereby increase the durability of the hydraulic system and tools.

  5. Specific features pertinent to modeling of hydraulic systems containing control members

    Tverskoy, Yu. S.; Marshalov, E. D.


    The theoretical principles applied for modeling of hydraulic systems fitted with control members that allow a hydraulic line's specific features (topology) to be taken into account are considered. Such modeling opens the possibility to predict the actual flow (throttling) characteristics at early design stages and timely introduce the appropriate corrections in pipeline topology. The modeling problem is solved with the use of generalized thermodynamic analysis methods. The mathematical models of hydraulic systems containing control members are brought to the level of real-time simulation models, which can be used for setting up computation experiments for achieving better performance of automatic closed-loop control systems.

  6. Fuzzy Control System of Hydraulic Roll Bending Based on Genetic Neural Network

    JIA Chun-yu; LIU Hong-min; ZHOU Hui-feng


    For nonlinear hydraulic roll bending control, a new fuzzy intelligent control method was proposed based on the genetic neural network. The method taking account of dynamic and static characteristics of control system has settled the problems of recognizing and controlling the unknown, uncertain and nonlinear system successfully,and has been applied to hydraulic roll bending control. The simulation results indicate that the system has good performance and strong robustness, and is better than traditional PID and neural-fuzzy control. The method is an effective tool to control roll bending force with increased dynamic response speed of control system and enhanced tracking accuracy.

  7. Position control of nonlinear hydraulic system using an improved PSO based PID controller

    Ye, Yi; Yin, Chen-Bo; Gong, Yue; Zhou, Jun-jing


    This paper addresses the position control of valve-controlled cylinder system employed in hydraulic excavator. Nonlinearities such as dead zone, saturation, discharge coefficient and friction existed in the system are highlighted during the mathematical modeling. On this basis, simulation model is established and then validated against experiments. Aim for achieving excellent position control performances, an improved particle swarm optimization (PSO) algorithm is presented to search for the optimal proportional-integral-derivative (PID) controller gains for the nonlinear hydraulic system. The proposed algorithm is a hybrid based on the standard PSO algorithm but with the addition of selection and crossover operators from genetic algorithm in order to enhance the searching efficiency. Furthermore, a nonlinear decreasing scheme for the inertia weight of the improved PSO algorithm is adopted to balance global exploration and local exploration abilities of particles. Then a co-simulation platform combining the simulation model with the improved PSO tuning based PID controller is developed. Comparisons of the improved PSO, standard PSO and Phase Margin (PM) tuning methods are carried out with three position references as step signal, ramp signal and sinusoidal wave using the co-simulation platform. The results demonstrated that the improved PSO algorithm can perform well in PID control for positioning of nonlinear hydraulic system.



    This paper reports results of research on the stability of a hydraulic servo position system using generalization pulse code modulation (GPCM) and common on/off valves for hydraulic servo control. The de- scribing function was first used to analyze the system′s stability, and based on the nonlinear theory, an equation calculating the minimum orifice area of GPCM valves was derived by applying results of analysis on the stability of the GPCM control system. In the end, aimed at developing a hydraulic servo position system to be used in a paint robot, simulation and experiment were carried out. The results show that the theoretical conclusions accorded with practical results.

  9. Knowledge-based Adaptive Tracking Control of Electro-hydraulic Actuator Systems

    Hansen, Poul Erik


    The paper deal with intelligent motion control and electro-hydraulic actuator systems for multiaxis machynes and robots.The research results are from the IMCIA research Programme supported by the Danish Technical Research Council, STVF.......The paper deal with intelligent motion control and electro-hydraulic actuator systems for multiaxis machynes and robots.The research results are from the IMCIA research Programme supported by the Danish Technical Research Council, STVF....

  10. An electro-hydraulic servo control system research for CFETR blanket RH

    Chen, Changqi [Hefei University of Technology, Hefei 230009, Anhui (China); Tang, Hongjun, E-mail: [Hefei University of Technology, Hefei 230009, Anhui (China); Qi, Songsong [Hefei University of Technology, Hefei 230009, Anhui (China); Cheng, Yong; Feng, Hansheng; Peng, Xuebing; Song, Yuntao [Institute of Plasma Physics Chinese Academy of Sciences, Hefei 230031, Anhui (China)


    Highlights: • We discussed the conceptual design of CFETR blanket RH maintenance system. • The mathematical model of electro-hydraulic servo system was calculated. • A fuzzy adaptive PD controller was designed based on control theory and experience. • The co-simulation models of the system were established with AMESim/Simulink. • The fuzzy adaptive PD algorithm was designed as the core strategy of the system. - Abstract: Based on the technical design requirements of China Fusion Engineering Test Reactor (CFETR) blanket remote handling (RH) maintenance, this paper focus on the control method of achieving high synchronization accuracy of electro-hydraulic servo system. Based on fuzzy control theory and practical experience, a fuzzy adaptive proportional-derivative (PD) controller was designed. Then a more precise co-simulation model was established with AMESim/Simulink. Through the analysis of simulation results, a fuzzy adaptive PD control algorithm was designed as the core strategy of electro-hydraulic servo control system.

  11. Co-Simulation Research of the Mechanical-Hydraulic-Control Coupling System of ITER Tractor

    YANG Xiuqing; LUO Minzhou; MEI Tao; YAO Damao


    The virtual prototyping models of the mechanical, hydraulic and control system of the ITER tractor were built with CATIA, ADAMS and MATLAB/Simulink respectively according to its heavy load and high precision characteristics, and the data transfer between the different models was accomplished by the integration interface between different software. Consequently the virtual experimental platform for the multi-disciplinary co-simulation was established. A co-simulation study of the mechanical-hydraulic-control coupling system of the ITER tractor was carried out. The synchronization servo control of parallel hydraulic cylinders was implemented, and the tracking control of the preconcerted trajectory of the hydraulic cylinders was realized on the established experimental platform. This paper presents the optimization design and technology rebuilding for the complicated coupling system with its theoretic foundation and co-simulation virtual experimental platform.

  12. Co-Simulation Research of the Mechanical-Hydraulic-Control Coupling System of ITER Tractor

    Yang, Xiuqing; Luo, Minzhou; Mei, Tao; Yao, Damao


    The virtual prototyping models of the mechanical, hydraulic and control system of the ITER tractor were built with CATIA, ADAMS and MATLAB/Simulink respectively according to its heavy load and high precision characteristics, and the data transfer between the different models was accomplished by the integration interface between different software. Consequently the virtual experimental platform for the multi-disciplinary co-simulation was established. A co-simulation study of the mechanical-hydraulic-control coupling system of the ITER tractor was carried out. The synchronization servo control of parallel hydraulic cylinders was implemented, and the tracking control of the preconcerted trajectory of the hydraulic cylinders was realized on the established experimental platform. This paper presents the optimization design and technology rebuilding for the complicated coupling system with its theoretic foundation and co-simulation virtual experimental platform.

  13. Research on Electro Hydraulic Proportional Control for Heavy Vehicle Blend Braking System

    XU Ming


    A blend braking system of heavy vehicle was proposed. The main control part of the system is the electro hydraulic proportional servo valve. A nonlinear model of brake cylinder controlled by the valve was deduced through the analysis of its control property and system feature. The transfer function of the system was also proposed, and the hydraulic inherent frequency and the PID closed-loop system feature were calculated. The simulated result is consistent with those tested in the bench and on the site with 50t heavy vehicle. The experimental result shows that the control method has quick response and high precision.

  14. Parameter Identification for the Valve Control Cylinder System of a Hydraulic Manipulator

    XIE Qing-hua; PEI Wen-kai; JIANG Bin; ZHANG Qi


    In mechanical, hydraulic and electronic systems, the determination of system parameters is often challenging because liquid parameters often change significantly, due to variations in working and environmental conditions. Therefore, it is of significant practical importance to identify those parameters through experimental procedures. A systematic approach to identifying parameters in the valve controlling cylinder system of hydraulic manipulators is provided. It first derives the transfer function of the system, and then uses P control of PID control to predict system parameters. The predicted parameters are further validated using PID control. The prediction through simulation using MatLab language is utilized, which agrees well with experimental results.

  15. FRF based position controller design through system identification for A hydraulic cylinder

    Seo, Hyoung Kyu; Kim, Dong Hwan [Dept. of Mechanical Design and Robot Engineering, Seoul National University of Science and Technology, Seoul (Korea, Republic of); Park, Jong Won [Reliability Assessment Center, Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)


    In this study, we have focused on the design of a controller and an operating program for the operation of the hydraulic actuators used in a shaker. To control the motion of the shaker accurately, the position of each hydraulic cylinder should be controlled precisely even under an uncertain environment. For this purpose, we have suggested a control algorithm using an FRF (frequency response function) based control which senses the behavior of the actuator in advance, calculates a transfer function through the system identification method, and provides the final control input. The experimental results on the performance of this system were compared with that of a simple PID control algorithm.

  16. Continuous rotary motor electro-hydraulic servo system based on the improved repetitive controller

    WANG Xiao-jing; JIANG ji-hai; LI Shang-yi


    In order to suppress the periodic interference of the continuous rotary electro-hydraulic servo motor,this paper makes the motor tracking the periodic signals with high accuracy,and improves the influence of friction interference to the performance of continuous rotary electro-hydraulic servo motor.The mathematic model of the electro-hydraulic position servo system of the continuous rotary motor was established,and the compound control method was adopted based on the repetitive control,feed forward and PID to suppress the friction interference.Through the simulation,the result confirms that the compound control method decreases the tracking error of the system,increases the robust performance of the system and improves the performance of the continuous rotary electro-hydraulic servo motor.

  17. Direct Drive Electro-hydraulic Servo Control System Design with Self-Tuning Fuzzy PID Controller

    Wang Yeqin


    Full Text Available According to the nonlinear and time-varying uncertainty characteristics of direct drive electro-hydraulic servo control system, a self-tuning fuzzy PID control method with speed change integral and differential ahead optimizing operator is put forward by combining fuzzy inference and traditional PID control in this paper.The rule of fuzzy logic is designed, the membership function of the fuzzy subsets is determined and lookup table method is used to correcte the PID parameters in real-time. Finally the simulation is conducted with the typical input signal, such as tracking step, sine etc. The simulation results show that,the self-tuning fuzzy PID control system can effectively improve the dynamic characteristic when the system is out of the range of the operating point compared with the traditional PID control system, there is obvious improvement in the indexes of rapidity, stability and accuracy,  and fuzzy self-tuning PID Control is more robust, and more suitable for direct drive electro-hydraulic servo system.

  18. PID Controller Optimization by GA and Its Performances on the Electro-hydraulic Servo Control System

    Karam M. Eibayomy; Jiao Zongxia; Zhang Huaqing


    A proportional integral derivative (PID) controller is designed and attached to electro-hydraulic servo actuator system (EHSAS) to control the angular position of the rotary actuator which control the movable surface of space vehicles. The PID gain parameters areoptimized by the genetic algorithm (GA). The controller is verified on the new state-space model of servo-valves attached to the physical rotary actuator by SIMULINK program. The controller and the state-space model are verified experimentally. Simulation and experimental results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as compared with the classical PID controller and the compensator controller.

  19. Robust Adaptive Backstepping Control Design for a Nonlinear Hydraulic-Mechanical System

    Choux, Martin; Karimi, Hamid Reza; Hovland, Geir


    converge to zero despite the uncertainties in the system according to the Barbalat lemma. The resulting controllers are able to take into account the interval uncertainties in Coulomb friction parameters and in the internal leakage parameters in the cylinders. Two adaptation laws are obtained by using......The complex dynamics that characterize hydraulic systems make it difficult for the control design to achieve prescribed goals in an efficient manner. In this paper, we present the design and analysis of a robust nonlinear controller for a nonlinear hydraulic-mechanical (NHM) system. The system...... consists of an electrohydraulic servo valve and two hydraulic cylinders. Specifically, by considering a part of the dynamics of the NHM system as a norm-bounded uncertainty, two adaptive controllers are developed based on the backstepping technique that ensure the tracking error signals asymptotically...

  20. Control method and system for hydraulic machines employing a dynamic joint motion model

    Danko, George


    A control method and system for controlling a hydraulically actuated mechanical arm to perform a task, the mechanical arm optionally being a hydraulically actuated excavator arm. The method can include determining a dynamic model of the motion of the hydraulic arm for each hydraulic arm link by relating the input signal vector for each respective link to the output signal vector for the same link. Also the method can include determining an error signal for each link as the weighted sum of the differences between a measured position and a reference position and between the time derivatives of the measured position and the time derivatives of the reference position for each respective link. The weights used in the determination of the error signal can be determined from the constant coefficients of the dynamic model. The error signal can be applied in a closed negative feedback control loop to diminish or eliminate the error signal for each respective link.

  1. Electro Hydraulic Hitch Control

    Hansen, M. R.; Andersen, T. O.; Nielsen, B.


    system for agricultural applications and driving for transportation. During tranport phases, the lack of suspension causes the vehicle to bounce and pitch, and makes it difficalt to control. Many systems have been proposed to cope with the oscillatory behavior, and different solutions exist. Common......This paper present and discusses R&D results on electro hydraulic hitch control for off-road vehicle, in particular active damping of oscillation occuring on tractors. The research deals with analysis and control of the oscillations occuring on tractors which are design without any susspection...... for most of the systems are that they operate on the hydrailc actuators generally providing the motive forces for moving the implement and/or attachment, typically a plough. The basic idea and physical working principle are to use the implement, moveable relative to the vehicle, as a damper mass. The paper...

  2. Adaptive impedance control of a hydraulic suspension system using particle swarm optimisation

    Fateh, Mohammad Mehdi; Moradi Zirkohi, Majid


    This paper presents a novel active control approach for a hydraulic suspension system subject to road disturbances. A novel impedance model is used as a model reference in a particular robust adaptive control which is applied for the first time to the hydraulic suspension system. A scheme is introduced for selecting the impedance parameters. The impedance model prescribes a desired behaviour of the active suspension system in a wide range of different road conditions. Moreover, performance of the control system is improved by applying a particle swarm optimisation algorithm for optimising control design parameters. Design of the control system consists of two interior loops. The inner loop is a force control of the hydraulic actuator, while the outer loop is a robust model reference adaptive control (MRAC). This type of MRAC has been applied for uncertain linear systems. As another novelty, despite nonlinearity of the hydraulic actuator, the suspension system and the force loop together are presented as an uncertain linear system to the MRAC. The proposed control method is simulated on a quarter-car model. Simulation results show effectiveness of the method.


    ZHANG Yanting; WANG Qingfeng; XIAO Qing; FU Qiang


    Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments.

  4. System and method for controlling engine knock using electro-hydraulic valve actuation

    Brennan, Daniel G


    A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

  5. Parallel Control of Velocity Control and Energy-Saving Control for a Hydraulic Valve-Controlled Cylinder System Using Self-Organizing Fuzzy Sliding Mode Control

    Chiang, Mao-Hsiung; Chien, Yu-Wei

    Conventional hydraulic valve-controlled systems that incorporate positive displacement pumps and relief valves have a problem of low energy efficiency. The objective of the research is to implement parallel control of energy-saving control in an electro-hydraulic load-sensing system and velocity control in a hydraulic valve-controlled cylinder system to achieve both high velocity control accuracy and low input power simultaneously. The overall control system is a two-input two-output system. For that, the control strategy of self-organizing fuzzy sliding mode control (SOFSMC) is developed in this study to reduce the fuzzy rule number and to self-organize on-line the fuzzy rules. To compare the energy-saving performance, the velocity control is implemented under three different energy-saving control systems, such as load-sensing control system, constant supply pressure control system and conventional hydraulic system. The parallel control of the velocity control and energy-saving control by the SOFSMC is implemented experimentally.

  6. Backstepping Adaptive Controller of Electro-Hydraulic Servo System of Continuous Rotary Motor

    XiaoJing Wang; ChangFu Xian; CaoLei Wan; JinBao Zhao; LiWei Xiu; AnCai Yu


    In order to consider the influence of the continuous rotary motor electro-hydraulic servo system parameters change on its performance, the design method of backstepping adaptive controller is put forward. The mathematical model of electro-hydraulic servo system of continuous rotary motor is established, and the whole system is decomposed into several lower order subsystems, and the virtual control signal is designed for each subsystem from the final subsystem with motor angular displacement to the subsystem with system control input voltage. Based on Lyapunov method and the backstepping theory, an adaptive backstepping controller is designed with the changed parameters adaptive law. It is proved that the system reaches the global asymptotic stability, and the system tracking error asymptotically tends to zero. The simulation results show that the backstepping adaptive controller based on the adaptive law of the changed parameters can improve the performance of continuous rotary motor, and the proposed control strategy is feasible.

  7. Experimental System Identification and Black Box Modeling of Hydraulic Directional Control Valve

    Sondre Sanden Tørdal


    Full Text Available Directional control valves play a large role in most hydraulic systems. When modeling the hydraulic systems, it is important that both the steady state and dynamic characteristics of the valves are modeled correctly to reproduce the dynamic characteristics of the entire system. In this paper, a proportional valve (Brevini HPV 41 is investigated to identify its dynamic and steady state characteristics. The steady state characteristics are identified by experimental flow curves. The dynamics are determined through frequency response analysis and identified using several transfer functions. The paper also presents a simulation model of the valve describing both steady state and dynamic characteristics. The simulation results are verified through several experiments.


    孟国营; 徐志强; 霍森; 方佳雨


    Having analyzed the drawbacks on the design of control system of hydraulic momentadjusted brake system, the author presents a closed loop control system in the process of start and braking of the conveyer. On the basis of the concept of the critical time and the critical acceleration and its deductions, the working mode of the conveyer can be identified and controlled in feedback, furthermore, thus realize the process of soft start. In the deceleration process, the author points out the problems that exist in the present control system and sets forward the control process that acted by the combined function of brake moment of motor and the drag torque of hydraulic brake at the beginning of deceleration, it will further improved reliability of conveyor system.

  9. Controls of Hydraulic Wind Turbine

    Zhang Yin


    Full Text Available In this paper a hydraulic wind turbine generator system was proposed based on analysis the current wind turbines technologies. The construction and principles were introduced. The mathematical model was verified using MATLAB and AMsim. A displacement closed loop of swash plate of motor and a speed closed loop of generator were setup, a PID control is introduced to maintain a constant speed and fixed frequency at wind turbine generator. Simulation and experiment demonstrated that the system can connect grid to generate electric and enhance reliability. The control system demonstrates a high performance speed regulation and effectiveness. The results are great significant to design a new type hydraulic wind turbine system.

  10. Cascade Controller Including Back-stepping for Hydraulic-Mechanical Systems

    Choux, Martin; Hovland, Geir; Blanke, Mogens


    Development of a cascade controller structure including adaptive backstepping for a nonlinear hydraulic-mechanical system is considered in this paper where a dynamic friction (LuGre) model is included to obtain the necessary accuracy. The paper compares the performance of two variants of an adapt...

  11. Using Feedback Error Learning for Control of Electro Hydraulic Servo System by Laguerre

    Amir Reza Zare Bidaki


    Full Text Available In this paper, a new Laguerre controller is proposed to control the electro hydraulic servo system. The proposed controller uses feedback error learning method and leads to significantly improve performance in terms of settling time and amplitude of control signal rather than other controllers. All derived results are validated by simulation of nonlinear mathematical model of the system. The simulation results show the advantages of the proposed method for improved control in terms of both settling time and amplitude of control signal.

  12. PI-type Iterative Learning Control for Nonlinear Electro-hydraulic Servo Vibrating System

    LUO Xiaohui; ZHU Yuquan; HU Junhua


    For the electro-hydraulic servo vibrating system(ESVS) with the characteristics of non-linearity and repeating motion, a novel method, PI-type iterative learning control(ILC), is proposed on the basis of traditional PID control. By using memory ability of computer, the method keeps last time's tracking error of the system and then applies the error information to the next time's control process. At the same time, a forgetting factor and a D-type learning law of feedforward fuzzy-inferring referenced displacement error under the optimal objective are employed to enhance the systemic robustness and tracking accuracy. The results of simulation and test reveal that the algorithm has a trait of high repeating precision, and could restrain the influence of nonlinear factors like leaking, external disturbance, aerated oil, etc. Compared with traditional PID control, it could better meet the requirement of nonlinear electro-hydraulic servo vibrating system.


    ZHONG Tianyu; WANG Qingfeng; LI Yanmin; GONG Fangyou


    Based on the pressure regulation circuit adopting electro-hydraulic proportional relief valve to control tension, a new type of electro-hydraulic compound control circuit with throttle control unit is presented, which can obtain optimal dynamic damping ratio through real-time altering pressure-flow gain of the throttle control unit, improve the dynamic characteristic of tension follow-up control for the tension system with high inertia loads. Moreover, the characteristic when the cable linear velocity variation causes change of tension is investigated, and a compound control strategy is proposed. The theoretical analysis and experimental results show that the electro-hydraulic compound control circuit is effective and the characteristic of the compound control strategy is satisfactory.

  14. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    Ye HUANG


    Full Text Available Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under light loads and wearing of the variable-displacement pump. To overcome these shortcomings, this article designs a closed hydraulic control system in which an AC servo motor drives a quantitative pump that controls a spiral swinging hydraulic cylinder, and analyzes and calculates the structure and parameters of a spiral swinging hydraulic cylinder. The hydraulic system adjusts the servo motor’s speed according to the requirements of the control system, and the motor power matches the power provided to components, thus eliminating the throttling loss of hydraulic circuits. The system is compact, produces a large output force, provides stable transmission, has a quick response, and is suitable as a hydraulic control system of a large butterfly valve.



    The variable structure control (VSC) theory is applied to the electro-hydraulic servo system here. The VSC control law is achieved using Lyapunov method and pole placement. To eliminate the chattering phenomena, a saturation function is adopted. The proposed VSC approach is fairly robust to load disturbance and system parameter variation. Since the distortion including phase lag and amplitude attenuation occurs in the system sinusoid response, the amplitude and phase control (APC)algorithm, based on Adaline neural network and using LMS algorithm, is developed for distortion cancellation. The APC controller is simple and can on-line adjust, thus it gives accurate tracking.

  16. Design, analysis and control of hydraulic soft yaw system for 5MW wind turbine

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole


    by active control of a hydraulic yaw system. The control is based on a non-linear and linear model derived based on a concept yaw system for the NREL 5MW wind turbine. The control strategies show a reduction in pressure pulsations under load and it is concluded that the strategie including high......As wind turbines increase in size and the demands for lifetime also increases, new methods of load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and wereby dampen the loads to the system. This paper presents work done on dampening of these loads...


    CHU Deying; ZHANG Zhiyi; WANG Gongxian; HUA Hongxing


    A high fidelity dynamic model of a high-energy hydraulically-actuated shock test machine for heavy weight devices is presented to satisfy the newly-built shock resistance standard and simulate the actual underwater explosion environments in laboratory as well as increase the testing capability of shock test machine. In order to produce the required negative shock pulse in the given time duration, four hydraulic actuators are utilized. The model is then used to formulate an advanced feedforward controller for the system to produce the required negative waveform and to address the motion synchronization of the four cylinders. The model provides a safe and easily controllable way to perform a "virtual testing" before starting potentially destructive tests on specimen and to predict performance of the system. Simulation results have demonstrated the effectiveness of the controller.

  18. Space Shuttle Main Engine control system. [hydraulic actuator with digital control

    Seitz, P. F.; Searle, R. F.


    The Space Shuttle Main Engine is a reusable, high-performance rocket engine being developed by the Rocketdyne Div. of Rockwell International to satisfy the operational requirements of the Space Shuttle Orbiter Vehicle. The design incorporates a hydraulically actuated, closed-loop servosystem controlled and monitored by a programmable electronic digital controller. The controller accepts vehicle commands for the various engine operational phases, positions the appropriate valves, monitors the engine for the required performance precisions and conditions, and provides redundancy management.

  19. Advance of Study on Design Methods of Hydraulic System of Radio Remote Control of Construction Machinery

    FENG Kai-lin; YANG Wei-min; CHEN kang-ning


    The working principle of radio remote controlling of construction machinery should be that signals of the radio wave from the transmitter obtained in the receiver were controlled and then changed into electronic analog or digital signals which can be used to drive different actuators and mechanisms of the vehicle.The vehicle could be acted by following the controlling instructions sent by the operator.The best operation mode of construction machinery is suitable not only to manual operating but also to remote controlling in the same vehicle.The design methods of the hydraulic system used for the radio remote controlling of construction machinery are discussed.The design methods of hydraulic circuits for the actuators controlled by solenoid on-off type valves,hydro-electronic multi-way proportional valves,closed loop proportional servo driver or three-way proportional reducing valves are discussed in detail (with real example).The design methods of the power shift transmission of electro-hydraulic controlling,the devices of braking and the directional streering are discussed in this paper.

  20. Model predictive control of servo motor driven constant pump hydraulic system in injection molding process based on neurodynamic optimization

    Yong-gang PENG; Jun WANG; Wei WEI


    In view of the high energy consumption and low response speed of the traditional hydraulic system for an injection molding machine, a servo motor driven constant pump hydraulic system is designed for a precision injection molding process, which uses a servo motor, a constant pump, and a pressure sensor, instead of a common motor, a constant pump, a pressure pro-portion valve, and a flow proportion valve. A model predictive control strategy based on neurodynamic optimization is proposed to control this new hydraulic system in the injection molding process. Simulation results showed that this control method has good control precision and quick response.

  1. Error Analysis and Compensation Method on the Mechanical Structure of the Hydraulic Control System

    Luo Yanyan


    Full Text Available Mechanical deformation of mechanical transmission part in hydraulic control system directly affects the loading accuracy of the system. For improving the mechanical properties of the system, The force analysis and motion analysis of mechanism are simulated based on the four-bar linkage structure (FLS, and kinematics simulation is designed by using Matlab program, then came to a system error bar graph. The system error was calculated accurately according to the results of the structural mechanics simulation made by Solidworks motion module. The structure of the system will be modified when systematic errors exceed the required limit values until it reach the required value.


    Wei Jianhua; Guan Cheng


    The velocity tracking control of a hydraulic servo system is studied. Since the dynamics of the system are highly nonlinear and have large extent of model uncertainties, such as big changes in load and parameters, a derivation and integral sliding mode variable structure control scheme (DI-SVSC) is proposed. An integral controller is introduced to avoid the assumption that the derivative of desired signal must be known in conventional sliding mode variable structure control, a nonlinear derivation controller is used to weaken the chattering of system. The design method of switching function in integral sliding mode control, nonlinear derivation coefficient and controllers of DI-SVSC is presented respectively. Simulation shows that the control approach is of nice robustness and improves velocity tracking accuracy considerably.

  3. Water Hydraulic Systems

    Conrad, Finn


    -going research projects on fluid power and mechatronics based on tap water hydraulic servovalves and linear servo actuators and rotary vane actuators for motion control and power transmission. Development and design a novel water hydraulic rotary vane actuator for robot manipulators. Proposed mathematical...... modelling, control and simulation of a water hydraulic rotary vane actuator applied to power and control a two-links manipulator and evaluate performance. The results include engineering design and test of the proposed simulation models compared with IHA Tampere University’s presentation of research...

  4. Status quo of applications of new control theories for hydraulic control systems; Shinseigyo riron no yuatsu eno oyo no genjo

    Yokota, S. [Tokyo Institute of Technology, Tokyo (Japan)


    This paper describes application of a new control theory to hydraulics. The modern control theory has become applied to hydraulics since about the 1940's, and optimal polarity arrangement by using the status feedback and adaptive control represented by MRAC have emerged. Thereafter, the robust control comes on stage as a fusion of the status space method and the frequency zone theory. For the application thereof, much discussions were given on adaptive control represented by MRAC in order to cover large variation in system parameters in hydraulic control. Since variable parameters are included, there are problems of identification of safety limit, and time delay. Fuzzy control allowing the mathematical model of the subject system to be unclear and neural net control are expanding their applications because of their easiness of handling. The robust control has also begun being applied partly, which is regarded useful for servos. Design freedom is high because target followability and stability are designed separately. However, reliable introduction of two-freedom degree control system such as H{sub {infinity}} control is indispensable. The paper also describes the single adaptive control (SAC) and the sliding mode control (SMC). (NEDO)

  5. PI control based on fuzzy set-point weighting tracking for hydraulic crane boom system

    Yong YANG; An LUO; Karl-Erik RYDBERG


    A PI control strategy based on fuzzy set-point weighting following was proposed for the active damping control of a hydraulic crane boom system (HCBS). Two valve-controlled PI controllers, which include a proportional feedforward controller based on fuzzy set-point weighting following and a limited semi-integrator(LSI), are designed respectively. LSI is used to limit output signal and to prevent wind up at the low frequency of the spectrum. By using a range camera and an electronic feedback control, the tip damping on the HCBS can be adjusted artificially. A collaborative control simulation technique of HOPSAN and MATLAB/SIMULINK is applied to the controller design. Simulation results show that the proposed PI control system has less overshoot as well as faster response. The tip damping on the HCBS during operation is improved.

  6. A switched energy saving position controller for variable-pressure electro-hydraulic servo systems.

    Tivay, Ali; Zareinejad, Mohammad; Rezaei, S Mehdi; Baghestan, Keivan


    The electro-hydraulic servo system (EHSS) demonstrates a relatively low level of efficiency compared to other available actuation methods. The objective of this paper is to increase this efficiency by introducing a variable supply pressure into the system and controlling this pressure during the task of position tracking. For this purpose, an EHSS structure with controllable supply pressure is proposed and its dynamic model is derived from the basic laws of physics. A switching control structure is then proposed to control both the supply pressure and the cylinder position at the same time, in a way that reduces the overall energy consumption of the system. The stability of the proposed switching control system is guaranteed by proof, and its performance is verified by experimental testing.

  7. Mechatronic System Design and Intelligent Motion Control of Hydraulic Robots and Machines

    Conrad, Finn; Sørensen, Torben


    The paper presents an approach and concept to mechatronic system design and intelligent motion control. The Information Technology (IT) offers software and hardware for improvement of R&D Mechatronic Teams to create products and solutions for industrial applications. The latest progress in IT makes...... control as well as from the Esprit project SWING on IT-tools for rapid prototyping of fluid power components and systems. A mechatronic test facility for a DTU-AAU hydraulic robot ¿Thor¿, and a CNC XY-machine table was implemented. The controller applies digital signal processors (DSPs). The DSP...... controller utilizes the dSPACE System suitable for real-time experimentation, evaluation and validation of control laws and algorithms....

  8. Proportional-integral-derivative control of nonlinear half-car electro-hydraulic suspension systems

    John E.D.EKORU; Jimoh O.PEDRO


    This paper presents the development of a proportional-integral-derivative (PID)-based control method for application to active vehicle suspension systems (AVSS).This method uses an inner PID hydraulic actuator force control loop,in combination with an outer PID suspension travel control loop,to control a nonlinear half-car AVSS.Robustness to model uncertainty in the form of variation in suspension damping is tested,comparing performance of the AVSS with a passive vehicle suspension system (PVSS),with similar model parameters.Spectral analysis of suspension system model output data,obtained by performing a road input disturbance frequency sweep,provides frequency response plots for both nonlinear vehicle suspension systems and time domain vehicle responses to a sinusoidal road input disturbance on a smooth road.The results show the greater robustness of the AVSS over the PVSS to parametric uncertainty in the frequency and time domains.

  9. Reduced-order model based active disturbance rejection control of hydraulic servo system with singular value perturbation theory.

    Wang, Chengwen; Quan, Long; Zhang, Shijie; Meng, Hongjun; Lan, Yuan


    Hydraulic servomechanism is the typical mechanical/hydraulic double-dynamics coupling system with the high stiffness control and mismatched uncertainties input problems, which hinder direct applications of many advanced control approaches in the hydraulic servo fields. In this paper, by introducing the singular value perturbation theory, the original double-dynamics coupling model of the hydraulic servomechanism was reduced to a integral chain system. So that, the popular ADRC (active disturbance rejection control) technology could be directly applied to the reduced system. In addition, the high stiffness control and mismatched uncertainties input problems are avoided. The validity of the simplified model is analyzed and proven theoretically. The standard linear ADRC algorithm is then developed based on the obtained reduced-order model. Extensive comparative co-simulations and experiments are carried out to illustrate the effectiveness of the proposed method.

  10. A compound control strategy combining velocity compensation with ADRC of electro-hydraulic position servo control system.

    Gao, Bingwei; Shao, Junpeng; Yang, Xiaodong


    In order to enhance the anti-jamming ability of electro-hydraulic position servo control system at the same time improve the control precision of the system, a compound control strategy that combines velocity compensation with Active Disturbance Rejection Controller (ADRC) is proposed, and the working principle of the compound control strategy is given. ADRC controller is designed, and the extended state observer is used for observing internal parameters uncertainties and external disturbances, so that the disturbances of the system are suppressed effectively. Velocity compensation controller is designed and the compensation model is derived to further improve the positioning accuracy of the system and to achieve the velocity compensation without disturbance. The compound control strategy is verified by the simulation and experiment respectively, and the simulation and experimental results show that the electro-hydraulic position servo control system with ADRC controller can effectively inhibit the external disturbances, the precise positioning control is realized after introducing the velocity compensation controller, and verify that the compound control strategy is effective.

  11. Hydraulic wind energy conversion system


    The purpose of this research was to design, build and test a hydraulic wind energy system. This design used a three bladed turbine, which drove a hydraulic pump. The energy is transmitted from the pump through a long hose and into a hydraulic motor, where the energy is used. This wind system was built and tested during the winter of 1980-1981. The power train included a five meter, three bladed wind turbine, a 9.8:1 ratio gearbox, a 1.44 cubic inch displacement pump with a small supercharge gear pump attached. The hydraulic fluid was pumped through a 70', 3/4'' I-D-high pressure flexhose, then through a volume control valve and into a 1.44 cubic inch displacement motor. The fluid was returned through a 70', 1'' I-D-flexhose.

  12. Trends in Modelling, Simulation and Design of Water Hydraulic Systems – Motion Control and Open-Ended Solutions

    Conrad, Finn


    The paper presents and discusses a R&D-view on trends in development and best practise in modelling, simulation and design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus...... process and mobile machines and equipment that operate in environmentally sensitive surroundings. Today’s progress in water hydraulics includes electro-water hydraulic proportional valves and servovalves for design of motion control solutions for machines and robots. The remarkable property...

  13. On Application of Second Order Sliding Mode Control to Electro-Hydraulic Systems

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.


    sliding algorithm known as the super twisting controller is considered for output feedback control and compared with conventional first order sliding mode control. The controllers under consideration are applied for position tracking control of a hydraulic valve-cylinder drive exhibiting strong variations...... in inertia- and gravitational loads. Results demonstrate that the super twisting algorithm may be successfully applied for output feedback control of hydraulic valve-cylinder drives, with modifications guaranteeing robust control performance in a small vicinity of the control target.......This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive...

  14. An energy-saving nonlinear position control strategy for electro-hydraulic servo systems.

    Baghestan, Keivan; Rezaei, Seyed Mehdi; Talebi, Heidar Ali; Zareinejad, Mohammad


    The electro-hydraulic servo system (EHSS) demonstrates numerous advantages in size and performance compared to other actuation methods. Oftentimes, its utilization in industrial and machinery settings is limited by its inferior efficiency. In this paper, a nonlinear backstepping control algorithm with an energy-saving approach is proposed for position control in the EHSS. To achieve improved efficiency, two control valves including a proportional directional valve (PDV) and a proportional relief valve (PRV) are used to achieve the control objectives. To design the control algorithm, the state space model equations of the system are transformed to their normal form and the control law through the PDV is designed using a backstepping approach for position tracking. Then, another nonlinear set of laws is derived to achieve energy-saving through the PRV input. This control design method, based on the normal form representation, imposes internal dynamics on the closed-loop system. The stability of the internal dynamics is analyzed in special cases of operation. Experimental results verify that both tracking and energy-saving objectives are satisfied for the closed-loop system.

  15. Force control compensation method with variable load stiffness and damping of the hydraulic drive unit force control system

    Kong, Xiangdong; Ba, Kaixian; Yu, Bin; Cao, Yuan; Zhu, Qixin; Zhao, Hualong


    Each joint of hydraulic drive quadruped robot is driven by the hydraulic drive unit (HDU), and the contacting between the robot foot end and the ground is complex and variable, which increases the difficulty of force control inevitably. In the recent years, although many scholars researched some control methods such as disturbance rejection control, parameter self-adaptive control, impedance control and so on, to improve the force control performance of HDU, the robustness of the force control still needs improving. Therefore, how to simulate the complex and variable load characteristics of the environment structure and how to ensure HDU having excellent force control performance with the complex and variable load characteristics are key issues to be solved in this paper. The force control system mathematic model of HDU is established by the mechanism modeling method, and the theoretical models of a novel force control compensation method and a load characteristics simulation method under different environment structures are derived, considering the dynamic characteristics of the load stiffness and the load damping under different environment structures. Then, simulation effects of the variable load stiffness and load damping under the step and sinusoidal load force are analyzed experimentally on the HDU force control performance test platform, which provides the foundation for the force control compensation experiment research. In addition, the optimized PID control parameters are designed to make the HDU have better force control performance with suitable load stiffness and load damping, under which the force control compensation method is introduced, and the robustness of the force control system with several constant load characteristics and the variable load characteristics respectively are comparatively analyzed by experiment. The research results indicate that if the load characteristics are known, the force control compensation method presented in this

  16. Hybrid Robust Control Law with Disturbance Observer for High-Frequency Response Electro-Hydraulic Servo Loading System

    Zhiqing Sheng


    Full Text Available Addressing the simulating issue of the helicopter-manipulating booster aerodynamic load with high-frequency dynamic load superimposed on a large static load, this paper studies the design of the robust controller for the electro-hydraulic loading system to realize the simulation of this kind of load. Firstly, the equivalent linear model of the electro-hydraulic loading system under assumed parameter uncertainty is established. Then, a hybrid control scheme is proposed for the loading system. This control scheme consists of a constant velocity feed-forward compensator, a robust inner loop compensator based on disturbance observer and a robust outer loop feedback controller. The constant velocity compensator eliminates most of the extraneous force at first, and then the double-loop cascade composition control strategy is employed to design the compensated system. The disturbance observer–based inner loop compensator further restrains the disturbances including the remaining extraneous force, and makes the actual plant tracking a nominal model approximately in a certain frequency range. The robust outer loop controller achieves the desired force-tracking performance, and guarantees system robustness in the high frequency region. The optimized low-pass filter Q(s is designed by using the H∞ mixed sensitivity optimization method. The simulation results show that the proposed hybrid control scheme and controller can effectively suppress the extraneous force and improve the robustness of the electro-hydraulic loading system.

  17. A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

    Yanfei Kou; Jieming Yang; Ziming Kou


    Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve) is proposed in this paper. The mathematic mode...

  18. Hydraulic Yaw System

    Stubkier, Søren; Pedersen, Henrik C.; Mørkholt, M.

    As wind turbines increase in size, combined with increased lifetime demands, new methods for load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hereby dampen the loads to the system, which is the focus of the current paper. By utilizing...... the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in critical components. Results shows that a significant reduction in fatigue and extreme loads to the yaw...... system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct...

  19. Hydraulic Motor Driving Variable-Pitch System for Wind Turbine

    Ye HUANG


    Full Text Available The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch system, the present hydraulic variable-pitch mechanism should be changed as follows: hydraulic motors are used to drive gears; gears drive blades; the electro-hydraulic proportional valves are used to control hydraulic motors. The hydraulic control part and electrical control part of variable-pitch system is redesigned. The new variable-pitch system is called hydraulic motor driving variable-pitch system. The new variable-pitch system meets the control requirements of blade pitch, makes the structure simple and its application effect is perfect.    

  20. Multi-objective optimization of the control strategy of electric vehicle electro-hydraulic composite braking system with genetic algorithm

    Zhang Fengjiao; Wei Minxiang


    Optimization of the control strategy plays an important role in improving the performance of electric vehicles. In order to improve the braking stability and recover the braking energy, a multi-objective genetic algorithm is applied to optimize the key parameters in the control strategy of electric vehicle electro-hydraulic composite braking system. Various limitations are considered in the optimization process, and the optimization results are verified by a software simulation platform of el...

  1. Improvement of diesel engine performance by hydraulically powered electronic control (mechatronics) system. Hakuyo diesel kikan no mechatronics system ni yoru seino kojo

    Sonoda, K.; Nakamura, Y.; Kajima, T.; Sato, S.; Fujii, T.; Tobe, Y. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))


    This paper describes new hydraulically-actuated mechanisms for both fuel injection and inlet/exhaust valve operation of diesel engines through solenoid valves, which obviate the conventional cam-driven system. These mechanisms were integrated with an electronic control unit also developed in this study and they were mounted as a mechatronics system'' on a power-increased single-cylinder engine. This mechatronics system was mainly composed of an injection control. boost and accumulation component, an inlet and exhaust valve control component, a solenoid valve, an electronic control equipment, a hydraulic power unit, and a maneuvering unit. The verification test was carried out for the improvement of diesel engine performance by the hydraulically powered mechatronics system. As a result, it was proved not only that these mechanisms provide stable operating characteristics over a wide range of conditions, but also that the electronic control system allows accurate, smooth response. 3 refs., 23 figs., 2 tabs.

  2. Nonlinear dynamic analysis and robust controller design for Francis hydraulic turbine regulating system with a straight-tube surge tank

    Liang, Ji; Yuan, Xiaohui; Yuan, Yanbin; Chen, Zhihuan; Li, Yuanzheng


    The safety and stability of hydraulic turbine regulating system (HTRS) in hydropower plants become increasingly important since the rapid development and the broad application of hydro energy technology. In this paper, a novel mathematical model of Francis hydraulic turbine regulating system with a straight-tube surge tank based on a few state-space equations is introduced to study the dynamic behaviors of the HTRS system, where the existence of possible unstable oscillations of this model is studied extensively and presented in the forms of the bifurcation diagram, time waveform plot, phase trajectories, and power spectrum. To eliminate these undesirable behaviors, a specified fuzzy sliding mode controller is designed. In this hybrid controller, the sliding mode control law makes full use of the proposed model to guarantee the robust control in the presence of system uncertainties, while the fuzzy system is applied to approximate the proper gains of the switching control in sliding mode technique to reduce the chattering effect, and particle swarm optimization is developed to search the optimal gains of the controller. Numerical simulations are presented to verify the effectiveness of the designed controller, and the results show that the performances of the nonlinear HTRS system assisted with the proposed controller is much better than that with the commonly used optimal PID controller.

  3. Hydraulic Closed Loop Synchronization Control System and Its Application in the Hydraulic Bending Machine%液压闭环同步控制系统在液压式卷板机中的应用



    This paper discusses the hydraulic open loop and closed loop system and its characteristics of synchronous control. The Application of hydraulic closed loop synchronization control system in hydraulic type three roller symmetrical bending machine was introduced in this paper.%论述了液压开环与闭环同步控制系统及其特点,并对液压闭环同步控制系统在液压式三辊对称卷板机中的应用进行了介绍。

  4. Simulation of a Hydraulic Pump Control Valve

    Molen, G. Vander; Akers, A.


    This paper describes the mode of operation of a control valve assembly that is used with a hydraulic pump. The operating system of the valve is modelled in a simplified form, and an analogy for hydraulic resonance of the pressure sensing system is presented. For the control valve investigated, air entrainment, length and diameter of the resonator neck, and valve mass produced the greatest shift in resonant frequency. Experimental work was conducted on the hydraulic system so that the resonance levels and frequencies could be measured and the accuracy of the theory verified. The results obtained make it possible to evaluate what changes to any of the variables considered would be most effective in driving the second harmonic frequency above the operating range.

  5. Nonlinear modeling and identification of the electro-hydraulic control system of an excavator arm using BONL model

    Yan, Jun; Li, Bo; Guo, Gang; Zeng, Yonghua; Zhang, Meijun


    Electro-hydraulic control systems are nonlinear in nature and their mathematic models have unknown parameters. Existing research of modeling and identification of the electro-hydraulic control system is mainly based on theoretical state space model, and the parameters identification is hard due to its demand on internal states measurement. Moreover, there are also some hard-to-model nonlinearities in theoretical model, which needs to be overcome. Modeling and identification of the electro-hydraulic control system of an excavator arm based on block-oriented nonlinear(BONL) models is investigated. The nonlinear state space model of the system is built first, and field tests are carried out to reveal the nonlinear characteristics of the system. Based on the physic insight into the system, three BONL models are adopted to describe the highly nonlinear system. The Hammerstein model is composed of a two-segment polynomial nonlinearity followed by a linear dynamic subsystem. The Hammerstein-Wiener(H-W) model is represented by the Hammerstein model in cascade with another single polynomial nonlinearity. A novel Pseudo-Hammerstein-Wiener(P-H-W) model is developed by replacing the single polynomial of the H-W model by a non-smooth backlash function. The key term separation principle is applied to simplify the BONL models into linear-in-parameters structures. Then, a modified recursive least square algorithm(MRLSA) with iterative estimation of internal variables is developed to identify the all the parameters simultaneously. The identification results demonstrate that the BONL models with two-segment polynomial nonlinearities are able to capture the system behavior, and the P-H-W model has the best prediction accuracy. Comparison experiments show that the velocity prediction error of the P-H-W model is reduced by 14%, 30% and 75% to the H-W model, Hammerstein model, and extended auto-regressive (ARX) model, respectively. This research is helpful in controller design, system

  6. Application of PLC in hydraulic transmission combination machine control system%PLC在液压传动组合机床控制中的应用



      液压传动控制系统主要用来控制液压动力元件(液压缸、液压马达)按照规定的要求进行动作。文章给出了采用PLC来代替传统继电器来控制液压控制元件,从而实现对液压动力元件的控制,提高液压控制的自动化程度和可靠性的PLC液压动力滑台的应用和实现方法,并通过实践证明了该方法的可靠性和易行性。%  The hydraulic transmission control system is mainly used to control the hydraulic components (including hydraulic cylinders and hydraulic motor) and make them operate according to the requirements. The paper presents how the PLC replaces traditional relay to control the hydraulic control components in order to achieve control of hydraulics components, and gives application and implementation method of PLC hydraulic power slide to increase the automation level and reliability of the hydraulic control. And the practice verifies the reliability and feasibility of the method.

  7. A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

    Yanfei Kou


    Full Text Available Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve is proposed in this paper. The mathematic model of water hammer fluctuations is established based on the characteristic line method. Then, boundary conditions of water hammer controlling for mine drainage system are determined and its simplex model is established. The optimization adjustment strategy is solved from the mathematic model of multistage valve-closing. Taking a mine drainage system as an example, compared results between simulations and experiments show that the proposed method and the optimized valve-closing strategy are effective.

  8. Plug & Play Control of Hydraulic Networks

    Jensen, Tom Nørgaard


    Process Control research program, which the work presented here is a part of. An industrial case study involving a large-scale hydraulic network with non-linear dynamics is studied. The hydraulic network underlies a district heating system, which provides heating water to a number of end-users in a city...... structure has the additional benefit that structural changes such as the addition or removal of end-users are easily implementable. In this work, the problem of controlling the pressure drop at the end-users to a constant reference value is considered. This is done by the use of pumps located both...... are considered. Some of the work considers control actions which are constrained to non-negative values only. This is due to the fact that the actuators in this type of system typically consist of centrifugal pumps which are only able to deliver non-negative actuation. Other parts of the work consider control...

  9. Compensation for secondary uncertainty in electro-hydraulic servo system by gain adaptive sliding mode variable structure control

    ZHANG You-wang; GUI Wei-hua


    Based on consideration of the differential relations between the immeasurable variables and measurable variables in electro-hydraulic servo system, adaptive dynamic recurrent fuzzy neural networks(ADRFNNs) were employed to identify the primary uncertainty and the mathematic model of the system was turned into an equivalent linear model with terms of secondary uncertainty. At the same time, gain adaptive sliding mode variable structure control(GASMVSC) was employed to synthesize the control effort. The results show that the unrealization problem caused by some system's immeasurable state variables in traditional fuzzy neural networks(TFNN) taking all state variables as its inputs is overcome. On the other hand, the identification by the ADRFNNs online with high accuracy and the adaptive function of the correction term's gain in the GASMVSC make the system possess strong robustness and improved steady accuracy, and the chattering phenomenon of the control effort is also suppressed effectively.

  10. 液压支架电液控制系统急停控制功能的设计与实现%Design and realization on emergency stop control function of electro-hydraulic control system of hydraulic support



    针对液压支架电液控制系统运行特点,提出了液压支架电液控制系统急停控制功能整体设计方案,通过基于单线 CAN 总线的急停通信电路实现了全系统的急停功能,并具有急停触发和解除时的高亮高分贝报警功能,能够在所有支架控制器上显示急停触发位置,对于系统通信故障、支架控制器复位及急停按钮损坏等故障有较好的适应能力,经过功能和性能测试,验证了该方案的可行性。%According to the operation characteristics of the electro-hydraulic control system of the hydraulic support, the paper proposed the whole design scheme to realize emergency stop control function of the electro-hydraulic control system of the hydraulic support, and the emergency stop of the whole system realized via the emergency stop circuit based on single-line CAN bus. In addition, highlighted and high decibel alarm took effect on emergency stop and release, and emergency stop triggering position displayed on all the support controllers. It possessed excellent adaptability for the faults about system communication, reset of support controller and damage of emergency button, and proved feasible after function and performance test.

  11. 14 CFR 29.1435 - Hydraulic systems.


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 29.1435 Section 29.1435... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each element of the hydraulic system...

  12. 14 CFR 23.1435 - Hydraulic systems.


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  13. Extended state observer–based fractional order proportional–integral–derivative controller for a novel electro-hydraulic servo system with iso-actuation balancing and positioning

    Qiang Gao


    Full Text Available Aiming at balancing and positioning of a new electro-hydraulic servo system with iso-actuation configuration, an extended state observer–based fractional order proportional–integral–derivative controller is proposed in this study. To meet the lightweight requirements of heavy barrel weapons with large diameters, an electro-hydraulic servo system with a three-chamber hydraulic cylinder is especially designed. In the electro-hydraulic servo system, the balance chamber of the hydraulic cylinder is used to realize active balancing of the unbalanced forces, while the driving chambers consisting of the upper and lower chambers are adopted for barrel positioning and dynamic compensation of external disturbances. Compared with conventional proportional–integral–derivative controllers, the fractional order proportional–integral–derivative possesses another two adjustable parameters by expanding integer order to arbitrary order calculus, resulting in more flexibility and stronger robustness of the control system. To better compensate for strong external disturbances and system nonlinearities, the extended state observer strategy is further introduced to the fractional order proportional–integral–derivative control system. Numerical simulation and bench test indicate that the extended state observer–based fractional order proportional–integral–derivative significantly outperforms proportional–integral–derivative and fractional order proportional–integral–derivative control systems with better control accuracy and higher system robustness, well demonstrating the feasibility and effectiveness of the proposed extended state observer–based fractional order proportional–integral–derivative control strategy.

  14. Multi-objective optimization of the control strategy of electric vehicle electro-hydraulic composite braking system with genetic algorithm

    Zhang Fengjiao


    Full Text Available Optimization of the control strategy plays an important role in improving the performance of electric vehicles. In order to improve the braking stability and recover the braking energy, a multi-objective genetic algorithm is applied to optimize the key parameters in the control strategy of electric vehicle electro-hydraulic composite braking system. Various limitations are considered in the optimization process, and the optimization results are verified by a software simulation platform of electric vehicle regenerative braking system in typical brake conditions. The results show that optimization objectives achieved a good astringency, and the optimized control strategy can increase the brake energy recovery effectively under the condition of ensuring the braking stability.

  15. Singular perturbation approach for control of hydraulically driven flexible manipulator

    LI Guang; WU Min


    The hydraulic flexible manipulator system is divided into two parts: flexible arm dynamics and hydraulic servomechanism, a driving Jacobian is derived to connect these two parts. Taking hydraulic actuator force as virtual input, a singular perturbed composite model is formulated and used to design composite controllers for the flexible link, in which the slow subsystem controller dominates the trajectory tracking, and then a fast controller is designed to damp out the vibration of the flexible structure. Moreover, the backstepping technique is applied to regulate the spool position of a hydraulic valve to provide the required force. Simulation results are provided to show the effectiveness of the presented approach.

  16. Experimental evaluation of control strategies for hydraulic servo robot

    Bech, Michael Møller; Andersen, Torben Ole; Pedersen, Henrik C.;


    In this paper different linear and non-linear controllers applied to a hydraulically driven servo robot are evaluated and validated. The task is to make the actuators of the manipulator track a position reference with minimum error. Hydraulic systems are intrinsically non-linear and using linear...... in industrial servo drives. The different controllers are compared and evaluated from simulation and experimental results....

  17. Design of active disturbance rejection controller for the hydraulic APC system of the rolling mill

    Zhang, Ruicheng; Chen, Zhikun


    Considering uncertain external disturbance, the model of automatic position control system is established. Then, according to the information of input and output, using extended states observer (ESO), a newer observer is proposed to observe and compensate this integrated disturbance, and a controller is designed based on active disturbance rejection control (ADRC). This controller has very strong robustness not only to external disturbance, but also to unpredictable plant parameter variations.

  18. Adaptive Sliding Mode Control for Hydraulic Drives

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.


    This paper presents a new adaptive sliding mode controller generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The proposed control scheme requires limited knowledge on system parameters, and employs only piston- and valve spool position feedback....... The main target is to overcome problems with linear controllers deteriorating performance due to the inherent nonlinear nature of such systems, without requiring extensive knowledge on system parameters nor advanced control theory. In order to accomplish this task, an integral sliding mode controller...... employing parameter adaption through a recursive algorithm is presented. This is based on a reduced order model approximation of a VCD with unmatched valve flow- and cylinder asymmetries. Bounds on parameters are obtained despite lack of parameter knowledge, and the proposed controller demonstrates improved...

  19. Mathematical model of electric hydraulic and powered support control system at a plough mining face

    ZHANG Wei; HAN Xiao; SUN Jing-jing


    Given the actual working of a fully mechanized plough at a mining face, we have proposed a formula for running con-straints between powered supports and a coal plough under assumed geological conditions of the coal face and, on this basis, estab-lished an automatic control model of powered supports for the coal plough face. We introduced the working principle of the pow-ered support control system of the plough at the mining face. We established three advanced characteristics of this control system: response speed, reliability and easy maintenance of the system. As well, we briefly introduced, the principal function of primary and subordinate controllers and the realization of the communication system by a Single Bus. Ten controllers were constructed and tested in our laboratorium. The results show that the control model is practical and meets actual conditions. It provides a theoretical basis for designing a computer control system for a powered support system of a plough at a mining face.

  20. 基于电液比例控制的液压支架搬运技术研究%Research on hydraulic support handling technology based on electro-hydraulic proportional control system

    周国力; 杨国宏


    Abstr act: According to the requirements of the working face of the coal mine hydraulic support installation and dismantle mechanization process, a novel kind of hydraulic support handling technology based on electro-hydraulic proportional control system is proposed. The hydrau lic drive system with proportional control technology uses the closed volume control circuit system of the electro-hydraulic proportional variable displacement pump control motor as the driving scheme of the hydraulic support transportation vehicle system. The Matlab software is used for the system simulation. In order to improve the stability and fast performance of the system, a genetic algorithm based PID correction control is presented and the simulation results show that the system has good stability and better control performance after correction.%根据煤矿井下工作面液压支架安装搬运的技术要求,提出了一种采用电液比例技术驱动控制的液压支架搬运系统。该系统采用电液控制技术,采用电液比例变量泵控马达闭式容积调速回路系统作为液压支架搬运系统的动力驱动方案。运用Matlab软件对系统进行了仿真。为了进一步改善系统的稳定性和快速性,提出了基于遗传算法的PID校正控制方案。仿真结果表明,校正后的系统具有较好的稳定性和控制效果。

  1. Synchronous control for the hydraulic width system of edger rolling mill

    Ning, Shurong; Fan, Zhuoyu


    Edger rolling mill is a load system in which the upper and the lower cylinder actuate a side vertical roller at the same time. Due to the linkage of the load, the output and control of two channels influence each other. Synchronic-control issue is discussed aim to the system with serious coupling. Neural network inverse as decoupling controller is proposed to account for the complicated process dynamics characterized by nonlinear, time-varying, uncertain and load couple properties. Firstly, the reversibility of the system is analyzed and the ANN inverse dynamic is constructed based on a feed forward and neural network structure with enlarged back propagation algorithm. Secondly, the system is changed into two pseudo-linear sub-system through connecting the controlled system and inverse dynamic model in series. Aim to two pseudo-linear sub-system pole assignments method is proposed to enhance the whole system performance. A series simulation was conducted and results showed the proposed controller does better than traditional PID not only on decoupling but also on the transient response, as well as robustness under vary conditions.

  2. Optimal design of Stewart platforms based on expanding the control bandwidth while considering the hydraulic system design

    Wei WANG; Hua-yong YANG; Jun ZOU; Xiao-dong RUAN; Xin FU


    We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart platform. The method is based on generalized natural frequency and takes hydraulic oil into consideration. A Lagrangian formulation which considers the whole leg inertia is presented to obtain the accurate equivalent mass matrix. Using the model, the effect of leg inertia and the influence of design parameters on the generalized natural frequency are investigated. Finally, numerical examples are presented to validate and confirm the efficiency of the mathematical model. The results show that the leg inertia, especially the piston part plays an important role in the dynamics. The optimum diameter ratio of the base to the moving platform is between 2 and 3, and the optimum joint angle ratio of the base to the moving platform is about 1. The smaller joint angles and a longer leg stroke are favorable for raising system frequencies. The system oil should be preprocessed for large platforms with a requirement for good dynamic performance.

  3. 船用多液动蝶阀启闭液压控制系统的设计%Design on Hydraulic Control System for Marine Muliti-hydraulic Butterfly Valve On-off

    于娜; 杨志贤; 毛卫平; 顾寄南


    A hydraulic system to realize the marine butterfly valve open-shut and opening was designed, and the project of the hy-draulic control system was made. Combining with the actual working condition of the system, the selection and parameter of the main components of the hydraulic system were analyzed and calculated. Considering the working feature of the hydraulic control system for marine butterfly valve, the hydraulic power unit was designed in automatic unloading mode and the accumulator was added to supply hydraulic oil assistantly in order to ensure the pressure maintain within the allowable scope of the work, and the safe and stable opera-tion of the whole system are ensured.%设计了一种船用蝶阀启、 闭液压控制系统,确定了该液压系统的控制方案;结合该系统的实际工况要求,对该系统中各主要元件的选型和参数进行了分析和计算;结合船用蝶阀液压遥控系统的工作特点,对液压泵站进行了设计,设置两台液压泵互为备用,并增加蓄能器辅助供油,同时泵站采用自动卸荷方式,保证系统油压维持在允许的工作范围内,从而确保了整个船用阀门液压遥控系统的的安全稳定运行.

  4. Transputer Control of Hydraulic Actuators and Robots

    Conrad, Finn


    Results from a Danish mechatronics research program entitled IMCIA - Intelligent Control and Intelligent Actuators. The objective is development of intelligent actuators for intelligent motion control. A mechatronics test facility with a transputer controlled hydraulic robot suiteable for real...

  5. High Pressure Hydraulic Distribution System


    to 500 0 F. 5 cycles. 5000 F room temperature to 50001F; 45 ______________ Icycles The tesis planned for the distribution system demonstrator were...American Society for Testing and Materials ASTM D412 - Tension Testing of Vulcanized Rubber ASTM D571 - Testing Automotive Hydraulic Brake Hose Society of

  6. Hydraulic fracturing system and method

    Ciezobka, Jordan; Salehi, Iraj


    A hydraulic fracturing system and method for enhancing effective permeability of earth formations to increase hydrocarbon production, enhance operation efficiency by reducing fluid entry friction due to tortuosity and perforation, and to open perforations that are either unopened or not effective using traditional techniques, by varying a pump rate and/or a flow rate to a wellbore.

  7. Robust control of a hydraulically driven flexible arm

    Guang LI; Khajepour AMIR


    A new robust controller is proposed to regulate both flexural vibrations and rigid body motion of a hydraulically driven flexible arm. The controller combines backstepping control and sliding mode to arrive at a controller capable of dealing with a nonlinear system with uncertainties. The sliding mode technique is used to achieve an asymptotic joint angle and vibration regulation in the presence of payload uncertainty by providing a virtual torque input at the joint while the backstepping technique is used to regulate the spool position of a hydraulic valve to provide the required torque. It is shown that there is no chatter in the hydraulic valve, which results in smoother operation of the system.

  8. Improvement of Hydraulic Edge Position Control System by Proportion Sliding Mode of Self-tuning Switching Gain

    Jin Baoquan


    Full Text Available Aiming at the problem of tracking performance degradation of hydraulic EPC system caused by time-varying inertia parameters, nonlinear and external disturbances, the proportion sliding mode control of fuzzy self-tuning gain was proposed. The EPC system state space model on deviation parameters was established and the main feedback sliding mode switching algorithm was designed. The fuzzy method was used to dynamically adjust the proportion sliding mode switching gain by product of the switching function and its derivative state and to adaptive compensate for the uncertainty of the system. At the same time to ensure the effectiveness of the design strategy, the controller model and physical model worked together to simulate the actual conditions. The fixed switching gain switch was, respectively greater and smaller and compared with the fuzzy self-tuning gain, in which the latter achieves a fast and coordinated control of chattering. The results show that after comprehensive consideration all interference the system is stable, fast response, high accuracy and to solve chattering problem caused by the traditional large switching gain of proportion sliding mode.

  9. Control arrangement for the actuation of hydraulic consumers

    Kussel, W.; Dettmers, M.; Weirich, W.


    An arrangement for controlling the actuation of hydraulic consumers, by selectively connecting the consumers to hydraulic pressure and return lines; the control arrangement comprising a respective hydraulically operated directional control valve associated with each of the hydraulic consumers, a respective electro-magnetically operated pre-control valve associated with each of the hydraulic directional control valves, and further electro-magnetically operated directional control valve means associated with the pre-control valves, each of the hydraulic consumers being connectible to the hydraulic pressure or return lines via the associated hydraulically operated directional control valve which is actuatable by a hydraulic control line leading from the output of the associated pre-control valve, wherein the inputs of the pre-control valves are connected directly to the hydraulic return line and indirectly, via the further control valve means, to the hydraulic return line or to a hydraulic control pressure line.

  10. Design of Spinning Forming Hydraulic Press's Hydraulics and Control System%旋压成形液压机液压系统及控制系统的设计

    李卫民; 丛树阳


    After careful analyzing the work of the hydrostatic press,the design project was determined,hydraulic schematic diagram of hydraulic spinning press was formulated,and pupm stations of the hydraulic system was designed.Using CAD technology designed integrated valves of the hydraulic system.The control system was based on the movement sequence of hydraulic system and the principle of automatic control.Through using the PLC and touch screen joint programming,PLC program development simulation software,the use of man-machine interface configuration software for configuration and programming and PLC and human-machine interface technology of communication,the key issuse of determining and selection of components and technical parameters in hydraulic system of the hydraulic spinning machine have been solved,as well as to the design of automatic control procedures and the control procedures and the control design of man-machine interface.%通过对旋压液压机的工况的分析,确定了设计方案,制定了完成旋压加工的旋压液压机液压原理图,设计了液压系统的液压泵站,采用CAD技术设计了集成式液压系统的集成块阀组;其控制系统是以液压系统的动作顺序和自动控制原理为基础,采用PLC和触摸屏联合编程技术、PLC程序开发软件编程模拟、人机界面运用组态软件进行组态和编程、PLC和人机界面的通讯等技术,解决了旋压液压机液压系统中各部件技术参数的确定与选用、自动控制程序的设计、人机界面的控制设计等关键问题.

  11. 14 CFR 25.1435 - Hydraulic systems.


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 25.1435 Section 25.1435... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1435 Hydraulic systems. (a) Element design. Each element of the hydraulic system must be designed to: (1) Withstand the proof...

  12. 14 CFR 27.1435 - Hydraulic systems.


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  13. Hydraulic control system of in-zone controlled calender%分区可控压光机的液压控制系统



    The principle of hydraulic control system of in-zone controlled calender was introduced. The static pressure sliding bearings can reduce mechanical wear and tear, to decrease the energy consumption and improve the paper quality.%介绍了分区可控压光机的液压控制系统的原理,结合分区可控辊和液压加压控制,利用液压静压滑动轴承的原理,减小机械设备磨损,降低工厂能耗,提高纸的质量。

  14. Robust Control of a Hydraulically Actuated Manipulator Using Sliding Mode Control

    Hansen, Michael Rygaard; Andersen, Torben Ole; Pedersen, Henrik Clemmensen


    This paper presents an approach to robust control called sliding mode control (SMC) applied to the a hydraulic servo system (HSS), consisting of a servo valve controlled symmetrical cylinder. The motivation for applying sliding mode control to hydraulically actuated systems is its robustness towa...

  15. Precision Force Control for an Electro-Hydraulic Press Machine

    Hong-Ming Chen


    Full Text Available This thesis is primarily intended to design a PC-based control system to control the force of an electro-hydraulic servo press system for implementing precision force control. The main feature is to develop a composite control by using the relief valve and the flow servo valve. Using feedback from a force sensor, a fuzzy controller was designed with LabVIEW software as the system control core for achieving a precision force control for the hydraulic cylinder on its travel and output. The weakness of hydraulic systems is that hydraulic oil is compressible and prone to leaking, and its characteristics can vary with oil temperature, thus making it difficult for a general linear controller to achieve accurate control. Therefore, a fuzzy controller was designed with LabVIEW along with a NI-PCI_6221 interface card and a load cell to control the servo valve flow and the relief valve to control the pressure source. The testing results indicate that accurate force control output of an electro-hydraulic servo press system can be obtained.

  16. Motion Planning Based Coordinated Control for Hydraulic Excavators

    GAO Yingjie; JIN Yanchao; ZHANG Qin


    Hydraulic excavator is one type of the most widely applied construction equipment for various applications mainly because of its versatility and mobility. Among the tasks performed by a hydraulic excavator, repeatable level digging or flat surface finishing may take a large percentage. Using automated functions to perform such repeatable and tedious jobs will not only greatly increase the overall productivity but more importantly also improve the operation safety. For the purpose of investigating the technology without loss of generality, this research is conducted to create a coordinate control method for the boom, arm and bucket cylinders on a hydraulic excavator to perform accurate and effective works. On the basis of the kinematic analysis of the excavator linkage system, the tip trajectory of the end-effector can be determined in terms of three hydraulic cylinders coordinated motion with a visualized method. The coordination of those hydraulic cylinders is realized by controlling three electro-hydranlic proportional valves coordinately. Therefore,the complex control algorithm of a hydraulic excavator can be simplified into coordinated motion control of three individual systems.This coordinate control algorithm was validated on a wheeled hydraulic excavator, and the validation results indicated that this developed control method could satisfaetorily accomplish the auto-digging function for level digging or flat surface finishing.

  17. 基于PLC的多层液压电梯控制系统设计%Design of Multi-layer Hydraulic Elevator Control System Based on PLC

    刘忠; 陈佳; 邹宇


    According to the hydraulic elevator speed control system, this paper puts forward the principle of hy-draulic elevator speed control system based on Siemens S7-200PLC controller, hardware configuration and con-trol method. Based on the special requirement of hydraulic elevator, the paper designs a complete electrical prin-ciple and wiring diagram, and provides a new design idea for the hydraulic elevator control system.%针对液压电梯调速系统的要求,基于西门子S7-200PLC控制器,提出了液压电梯速度控制系统的原理、硬件配置及控制方法。结合液压电梯的特殊要求,设计了完整的电气原理以及接线方式图,为液压电梯控制系统提供了一种新的设计思路。

  18. 液压比例控制系统在液压支架用安全阀试验台上的应用%Application of Hydraulic Proportional Control System in Hydraulic Safety Valve Test Table



    针对原液压支架用安全阀试验台流量调节过程繁琐、效率及检测精度低的问题,采用比例控制技术,进行闭环流量控制.改进了试验台的液压系统,实现了流量调节的自动化,提高了试验效率及检测精度.%There are problems existing in the original hydraulic safety valve test bench,including complicated flow controlling process and low accuracy and detection efficiency.To solve the problems,the proportional control technology was used to realize closed-loop flow control.The hydraulic system of the experiment platform was improved.The automation of flow regulation is realized,and the test efficiency and accuracy are improved.

  19. Development of hydraulic brake actuator for active brake control; Active brake seigyoyo yuatsu booster no kaihatsu

    Konishi, Y.; Hattori, M. Sugisawa, M.; Nishii, M. [Aisin Seiki Co. Ltd., Aichi (Japan)


    Recently, application of active brake control systems of the vehicle are increasing. (Vehicle stability control, Panic brake assist ) We have developed a new hydraulic brake actuator for active brake control systems. New hydraulic brake actuator is composed of the three parts. (Hydraulic booster unit, Power supply unit, Control valve unit) This report describes the construction of the new hydraulic booster unit. 2 refs., 10 figs.

  20. Tidal current turbine based on hydraulic transmission system

    Hong-wei LIU; Wei LI; Yong-gang LIN; Shun MA


    Tidal current turbines (TCTs) are newly developed electricity generating devices.Aiming at the stabilization of the power output of TCTs,this paper introduces the hydraulic transmission technologies into TCTs.The hydrodynamics of the turbine was analyzed at first and its power output characteristics were predicted.A hydraulic power transmission system and a hydraulic pitch-controlled system were designed.Then related simulations were conducted.Finally,a TCT prototype was manufactured and tested in the workshop.The test results have confirmed the correctness of the current design and availability of installation of the hydraulic system in TCTs.

  1. Transputers in Fluid Power - Design and Applications. Chapter 5 in Advances in Hydraulic Control Systems

    Conrad, Finn

    Deals with results and trends on mechatronics in fluid power and intelligent control of machines and robots. New results are presented concerning transputer-basen distributed control of machines and robots. Experimental results with the DTU mechatronic test facility are presented and discussed. S....... Several adaptive control algoritms are investigated and evaluated. Promissing results are obtained with Computed Valve-Input Control (CIC), Adaptive Model-based Actuator Control (AMAC) and Linear Pertubation Adaptive Control (LPAC).......Deals with results and trends on mechatronics in fluid power and intelligent control of machines and robots. New results are presented concerning transputer-basen distributed control of machines and robots. Experimental results with the DTU mechatronic test facility are presented and discussed...

  2. System Topology Optimization - An Approach to System Design of Electro-Hydraulic-Mechanical Systems

    Andersen, T. O.; Hansen, M. R.; Conrad, Finn


    design the procedure attempts to find the optimal topology and the related parameters. The topology considerations comprise the type of hydraulic pump, the employment of knee linkages or not as well as the type of hydraulic actuators. The design variables also include the signals to the proportional......The current paper presents an approach to system design of combined electro-hydraulic-mechanical systems. The approach is based on the concurrent handling of the topology as well as the design parameters of the mechanical, hydraulic and controller sub- systems, respectively. Based on an initial...... valve in a number of predefined load cases as well as the hydraulic and mechanical parameters....

  3. Concept Evaluation for Hydraulic Yaw System

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole


    a suspension system on a car, leading the loads away from the turbine structure. However, to realize a soft hydraulic yaw system a new design concept must be found. As a part of the development of the new concept a preliminary concept evaluation has been conducted, evaluating seven different hydraulic yaw...... concepts, ranging from a one-to-one copy of the electrical drive (electrical drives replaced by hydraulic dittos), to floating suspension systems mounted on hydraulic cylinders. Rough calculations of size and consequences of the different systems are presented ending up with the final concept for further...

  4. Numerical Simulation of Hydraulic Control System for Marine Butterfly Valve%船用蝶阀液压控制系统的数值仿真

    刘辉; 戈亮; 严军


    液控蝶阀以其启闭扭矩大、压力损失小和适合用于大中口径管道等特点,在船舶领域得到了广泛应用.基于船舶中某一常用规格的中线对称阀瓣的液控蝶阀,建立该液控蝶阀在实际工况下启闭控制液压系统的数学模型,并进行数值仿真和试验研究.仿真及试验结果表明:液控蝶阀启闭时的转动角速度及其误差受蓄能器排油量、管路压力损失、液压介质的温度以及液控蝶阀的负载影响较大.这一仿真分析及试验结果可为蝶阀液压控制系统中蓄能器总容量和管路通径的选择、液控蝶阀结构型式和规格的确定及其所输送流体运动参数的设计提供依据.%Hydraulic control butterfly valve is widely used in marine area due to the following features: high torque, low pressure loss and be suitable for medium and large diameter pipeline, etc. In this paper, hydraulic control butterfly valve adopted common centerline symmetry flap, and mathematical model of the switch control hydraulic system for hydraulic control butterfly valve was established. Numerical simulation and experiment results show that; row oil of the accumulator, pipeline pressure loss, temperature of hydraulic medium and the load have great impact on the rotational angular velocity and its error when the hydraulic control valve is opening and closing. The results can be applied to selection of the total capacity of accumulator and pipeline path, and to determination of structure type and specifications for hydraulic control butterfly valve and design of the motion parameters for the fluid transported by the system.

  5. Discussion on Methods of Proportional Pressure Control in Hydraulic System of Hydraulic Press%液压机液压系统比例压力控制方法探讨

    李贵闪; 翟华


    Three methods of proportional pressure control on hydraulic presses were introduced and compared, which were open-loop control, closed-loop control based on PID and PID control with addition of initial signals. Results of comparison showe that the closed-loop control algorithm which is added with initial signals has many advantages such as simple control structure, easy debugging operations, stable system and high precision, and etc. The requirements of this hydraulic press on pressure control can be fully satisfied.%介绍了液压机比例压力控制的3种方法,即开环控制、基于PID的闭环控制、加入初始信号的PID控制.并对3种控制方法进行了比较.结果表明:采取的加入初始信号的闭环控制算法具有控制结构简单、调试方便、系统稳定、精度高等优点,完全满足该液压机对压力控制的要求.

  6. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States); Basher, A.M.H. [South Carolina State Univ., Orangeburg, SC (United States)


    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (ORNL) has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  7. Modeling and controlling of a flexible hydraulic manipulator

    LI Guang; WU Min


    A mathematical model was developed combining the dynamics of an Euler-Bernoulli beam, described by the assumed-mode method and hydraulic circuit dynamics. Only one matrix, termed drive Jacobian, was needed in the modeling of interaction between hydraulic circuit and flexible manipulator mechanism. Furthermore, a new robust controller based on mentioned above dynamic model was also considered to regulate both flexural vibrations and rigid body motion. The proposed controller combined sliding mode and backstepping techniques to deal with the nonlinear system with uncertainties. The sliding mode control was used to achieve an asymptotic joint angle and vibration regulation by providing a virtual force while the backstepping technique was used to regulate the spool position of a hydraulic valve to provide the required control force. Simulation results are presented to show the stabilizing effect and robustness of this control strategy.

  8. Power Management in Mobile Hydraulic Applications - An Approach for Designing Hydraulic Power Supply Systems

    Pedersen, Henrik Clemmensen


    in a project to develop rules and methods for designing and controlling mobile hydraulic systems in the most energy efficient way, when also considering the operational aspects of the system. The paper first describes the thoughts and ideas behind the project and then focus on an automated approach to design......Throughout the last three decades energy consumption has become one of the primary design aspects in hydraulic systems, especially for mobile hydraulic systems, as power and cooling capacity here is at limited disposal. Considering the energy usage, this is dependent on component efficiency......, but even more important is the system topology. However, there are no rules or guidelines for what system topology to choose for a given application, in order to obtain the most energy efficient system, nor for how the energy should be distributed in the system. This paper describes the approach taken...

  9. Modeling and parameter estimation for hydraulic system of excavator's arm

    HE Qing-hua; HAO Peng; ZHANG Da-qing


    A retrofitted electro-bydraulic proportional system for hydraulic excavator was introduced firstly. According to the principle and characteristic of load independent flow distribution(LUDV)system, taking boom hydraulic system as an example and ignoring the leakage of hydraulic cylinder and the mass of oil in it,a force equilibrium equation and a continuous equation of hydraulic cylinder were set up.Based On the flow equation of electro-hydraulic proportional valve, the pressure passing through the valve and the difference of pressure were tested and analyzed.The results show that the difference of pressure does not change with load, and it approximates to 2.0 MPa. And then, assume the flow across the valve is directly proportional to spool displacement andis not influenced by load, a simplified model of electro-hydraulic system was put forward. At the same time, by analyzing the structure and load-bearing of boom instrument, and combining moment equivalent equation of manipulator with rotating law, the estimation methods and equations for such parameters as equivalent mass and bearing force of hydraulic cylinder were set up. Finally, the step response of flow of boom cylinder was tested when the electro-hydraulic proportional valve was controlled by the stepcurrent. Based on the experiment curve, the flow gain coefficient of valve is identified as 2.825×10-4m3/(s·A)and the model is verified.


    FANG Yu; YANG Jian; CHAI Xiaodong


    A robust control algorithm is proposed to focus on the non-linearity and variables of the hydraulic press machine with the proportional valve. The proposed robust controller does not need to design stable compensator in advance, which is simple in design and has large scope of uncertainty applications. The feedback gains of the proposed robust controller are small, so it is easily implemented in engineering applications. The theoretical and experimental research on the position and speed control of the hydraulic press machine is carried out. The control requirements of the hydraulic press machine during the working process are met in the position and speed at the same time. Experimental results show that the proposed controller has better robustness subject to load variables and adaptability of parameter variations of the hydraulic press machine with the proportional valve.

  11. Analysis of nonlinearities and effects in direct drive electro-hydraulic position servo system

    WANG Hong-jie; JI Tian-jing; MAO Xin-tao; LIU Quan-zhong


    The direct drive electro-hydraulic servo system is a new approach hydraulic system. It is much smaller and easier controlled than traditional systems and is a perfect energy saver. This paper will briefly introduce the popular nonlinearities in the electro-hydraulic system and analyse the effect of nonlinearities in direct drive electro-hydraulic position servo system by means of simulation research. Some valuable conclusions are given.

  12. 金属带式CVT钢带轴向跑偏电液控制系统的仿真%Simulation of Electro- hydraulic Control System of Controling the Belt Axial - misalignment for Metal V- belt CVT

    臧发业; 张玉波


    On the basis of the analysis of the belt misalignment of the metal V - belt CVT, the reason of the belt misalignment is discussed. In order to control the misalignment, an electro - hydraulic control system is designed. After analyzing the structure and principle of the electro - hydraulic control system, the mathematical model of the electrohydraulic control system is established. Being varieties of the working situation of car and the non - linearity of the electro - hydraulic control system, a fuzzy PID algorithm is adopted. Then the performance simulation of the electro - hydraulic control system is conducted. The simulation results showe that the electro - hydraulic control system and the fuzzy controller with parameter self adjustment could not only control ratio, which has a higher accuracy of the stable state and a stronger robust of the driving condition, but also eliminate the belt misalignment.%通过对金属带式无级变速器传动钢带轴向跑偏的分析,阐述了产生钢带中心线轴向偏移的原因,为控制传动钢带的轴向跑偏,设计了一种新型的电液伺服控制系统,阐述了其工作原理,建立了该系统的数学模型.由于系统具有非线性及工况运行的复杂性,采用模糊控制算法,然后对系统的控制性能进行仿真研究,仿真结果表明,所设计的电液伺服控制系统能实现对速比的跟踪控制,稳态精度较高,可消除金属带式CVT传动钢带的轴向跑偏.

  13. 水下生产控制系统液压动力模拟分析%Hydraulic Power Simulation Analysis for Subsea Production Control System

    周声结; 戚蒿


    对水下生产系统的液压系统、电力系统和通信系统进行不同工况下的性能分析是保障水下生产装置安全可靠工作的关键.以中海石油(中国)有限公司湛江分公司某气田开发工程项目水下生产系统的液压系统构架及参数分析为例,介绍了运用“The Control Simulator”软件进行液压动力分析的要点.分析在最小和最大井口关断压力下阀门的开关响应时间、阀门打开之后压力恢复时间、序列阀门开启时间、ESD指令下关阀响应时间等,并将分析结果和实际生产情况进行对比,可知该液压系统的各项性能指标均满足相应标准和规范的要求.%The performance analyses in various cases for hydraulic system,power system and communication system of subsea production system are the key to ensure the subsea production equipment working reliably.Based on the hydraulic system architecture and performance analysis of a gas field development project of CNOOC Ltd._ Zhanjiang,the key points of applying software "The Control Simulator" to make hydraulic system performance analysis were presented.By analyzing valve actuator operating time,hydraulic pressure recovering times,valve opening time in series,valve closing time in ESD command under maximum and minimum wellhead shut-in pressure and comparing the conclusions with actual operating case,it is shown that the hydraulic system meets the requirement of corresponding standard.

  14. Automated Hydraulic System Design and Power Management in Mobile Applications

    Pedersen, Henrik Clemmensen

    and therefore there is today a shift towards using electric drives as replacement for hydraulic drives. There are, however, a number of different areas, where hydraulic systems offers possibilities that cannot be matched by electric drives, as the hydraulic systems are typically characterised by a much higher...... and accuracy, energy consumption is becoming an ever more important design parameter. At the same time as the first oil crisis the first hydraulic load sensing (LS) systems also emerged on the market, which, compared to the other systems of the time, offered significant energy saving potentials and which today...... do either not exist for ensuring that the system designed is actually suited for a given application. Today a change is furthermore happening, where new and more intelligent components, which are electrically controllable, are emerging and more and more sensors are finding their way...

  15. Simulation and control of an electro-hydraulic actuated clutch

    Balau, Andreea-Elena; Caruntu, Constantin-Florin; Lazar, Corneliu


    The basic function of any type of automotive transmission is to transfer the engine torque to the vehicle with the desired ratio smoothly and efficiently and the most common control devices inside the transmission are clutches and hydraulic pistons. The automatic control of the clutch engagement plays a crucial role in Automatic Manual Transmission (AMT) vehicles, being seen as an increasingly important enabling technology for the automotive industry. It has a major role in automatic gear shifting and traction control for improved safety, drivability and comfort and, at the same time, for fuel economy. In this paper, a model for a wet clutch actuated by an electro-hydraulic valve used by Volkswagen for automatic transmissions is presented. Starting from the developed model, a simulator was implemented in Matlab/Simulink and the model was validated against data obtained from a test-bench provided by Continental Automotive Romania, which includes the Volkswagen wet clutch actuated by the electro-hydraulic valve. Then, a predictive control strategy is applied to the model of the electro-hydraulic actuated clutch with the aims of controlling the clutch piston displacement and decreasing the influence of the network-induced delays on the control performances. The simulation results obtained with the proposed method are compared with the ones obtained with different networked controllers and it is shown that the strategy proposed in this paper can indeed improve the performances of the control system.


    I. V. Zhukovytskyy


    authors developed the information-measuring system that improves the hydraulic transmission test process by automating and increasing the accuracy of measurements of control parameters. The measurement results are initial data for carrying out further studies to determine the technical condition of the hydraulic transmission UGP750-1200 during the plant post-repair tests. Practical value. The paper proposed the alternate design of microprocessor hydraulic transmission test system for diesel locomotives, which has no analogues in Ukraine. Automated data collection during the tests will allow capturing the fast processes to determine the technical condition of hydraulic transmission.

  17. Analysis and control of flows in pressurized hydraulic networks

    Gupta, R.K.


    Analysis, design and flow control problems in pressurized hydraulic networks such as water transmission and distribution systems consisting of pipes and other appurtenant components such as reservoirs, pumps, valves and surge devices are dealt with from the prospective of network synthesis aiming at

  18. 一种船用液压舵机控制系统设计%Design of Hydraulic Servo Control System for Ship

    汪永生; 王洪波


    Aiming at small and medium ships,an open-loop type hydraulic servo control system was designed which had a simple structure and taking up small space. Adopting the system,the rudder machine works more steadily.%针对中小型船舶,设计一种结构简单、占用空间小的开式回路液压控制系统,同时采用了回油节流调速回路,使得舵机工作比较平稳。


    Wang Qingfeng; Zhao Ju; Yang Botao


    A statistic linearization analysis method of bad nolinear hydraulic active damping suspensiop is provided.Also the optimum control strategy of semi-active suspension and graded control strategy based on it are puted forward.Experimental researches are carried out on a 2 DOF (degree of freedom ) hydraulic active damping suspension test system.The results showed that an excellent control effectiveness could be obtained by using statistic linearization optimum control which unfortunely requests continuously regulationg the damp in an accurate way and costs much in engeering application.On the contrary,the results also showed that graded control is more practicable which has a control effectiveness close to the optimum control and costs less.

  20. Intelligent PI Fuzzy Control of An Electro-Hydraulic Manipulator

    Ayman A. Aly


    Full Text Available The development of a fuzzy-logic controller for a class of industrial hydraulic manipulator is described. The main element of the controller is a PI-type fuzzy control technique which utilizes a simple set of membership functions and rules to meet the basic control requirements of such robots. Using the triangle shaped membership function, the position of the servocylinder was successfully controlled. When the system parameter is altered, the control algorithm is shown to be robust and more faster compared to the traditional PID controller. The robustness and tracking ability of the controller were demonstrated through simulations.

  1. 液控核辐射环境拆除机器人控制系统%Control System for Hydraulic Demolition Robot Used in Nuclear Environment

    皮明; 杨涛; 张华


    在核电站、核设施和其他一些强辐射高危环境中,遥控拆除机器人技术得到了广泛的应用,通过遥控摄像机进行远距离监视、控制和操纵拆除机器人工作,完成拆除核设施,搬运、分拣、装运核废料和有毒物质,以及其他一些劳动强度大、危险性高的工作。液控拆除机器人体积小、力量大、机动性强,可快捷、高效地投入危险环境中。针对核辐射环境下的应用要求,研制开发了一种液压驱动的拆除机器人系统,并对其几何结构特性和液控系统进行了详细分析,最后通过ADAMS与EASY5的联合仿真,验证了液控系统的有效性。%In the nuclear power station,nuclear facilities and strong radiation risk environment,technology of remote control demolition robot is widely used. The working of robot was monitored in far off distance,regulated and operated through the remote cam-eras,to complete demolition,selecting,remove and transport toxic nuclear waste,and some other high intensity-risk labor. The hy-draulic controlled demolition robot had smaller volume,more force and high mobility,which could be deployed more effectively and rapidly in dangerous environment. Aimed at the requirement of application in radiation environment,the system of demolition robot controlled by hydraulic was developed,and its geometric structural characteristics and hydraulic control system were analyzed in detail. At last,a co-simulation is carried out between ADAMS and EASY5,verifying effectiveness of hydraulic control system.

  2. Fire Resistant Aircraft Hydraulic System.


    and compounds based on new experimental elastomers as well as most commercially available elastomers were screened in seeking seals that were both...for hydraulic component testing. All of the available E6.5 stock was purchased for the screening tests. However, DuPont stated that other homologs of...with the lubricity and anti-wear additive olyvan A (molybdenum oxysulphide dithiocarbamate ) added in the quantity of less than one percent by weight

  3. Analysis and Reform on Reliability of Circulating Water Pump and Hydraulic-control Butterfly Valve Control System%循环水泵及液控蝶阀控制系统可靠性分析及改造



    This paper introduces and analyzes existing problems of circulating water pump and hydraulic-control butterfly valve control system in Guangdong Datang Chaozhu power plant and proposes optimization measures for improving reliabili-ty.Referred measures are feasible to greatly improve reliability of circulating water pump and hydraulic-control butterfly valve control system and safety of the unit.%对广东大唐潮州电厂循环水泵、液控蝶阀控制系统存在的问题进行了介绍和分析,并提出提高可靠性改造的优化措施。这些措施大大提高了循环水泵及液控蝶阀控制系统的可靠性及机组的安全性。

  4. Analysis of an controller design for an electro-hydraulic servo pressure regulator

    Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.;


    of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus of the current paper is therefore on the analysis and controller design an electro-hydraulic servo pressure...... regulator, which generates a hydraulic LS-pressure based on an electrical reference, hereby synergistically integrating knowledge from all parts of the mechatronics area. The servo pressure regulator is used to generate the LS-signal for a variable displacement pump, and the paper rst presents...... to generate a controlled leakage  ow that aids in stabilising the system. The robustness of the system is then discussed in relation to dierent pilot line volumes and pump dynamics. Finally experimental results are presented, where the performance is compared to that of a similar hydraulic reference system...

  5. 基于 PLC 的液压滑台控制系统设计%Design of Hydraulic Control System Based on PLC



    Aiming at the existing problem of relay contactor control system ,this article used PLC technology to control the feeding motion of hydraulic sliding table .The PLC models was chosen ,the hardware and software were designed ,and the ladder diagram was given .The system has been applied to the actual cutting process ,and the feasibility and practicability has been verified .%针对继电器接触器控制系统存在的问题,采用PLC技术对液压动力滑台进给运动进行控制。选择了PLC机型,进行了硬件设计、软件设计,并画出了梯形图。应用于实际切削过程中,验证了其可行性和实用性。

  6. XJ250修井机液压盘式刹车液压控制系统仿真分析%Simulation Analysis of the Hydraulic Control System of the Hydraulic Disc Brake on the X J250 Workover Rig

    张连业; 吴文秀; 刘威


    Taking as the object of study the hydraulic control system of the hydraulic disc brake on the XJ250 workover rig, the mathematical model on the basis of global flow and hydraulic cylinder piston motion equation was established by analyzing the structure of the control system. The AMESim simulation model for the hydraulic control system of the braking system was constructed and the model parameters and simulation parameters were set. The var- iation of the typical sine curve hydraulic source signal and excitation electromagnetic valve signal was used to carry out a simulation study of the response system of the operating brake hydraulic control system. The sudden opening of the step switch signal was used to conduct a simulation analysis of the urgency brake hydraulic system response. The hydraulic dynamic response curve of the main valve port of the hydraulic control system in the process of operating brake and urgency brake was derived. The simulation result is in agreement with the practical operation. The simulation analysis offers a reference for the improvement of the performance of the hydraulic control system of the workover rig disc brake.%以XJ250修井机液压盘式刹车的液压控制系统为研究对象,通过分析液压盘式刹车的液压控制系统结构,建立了基于全局流量与液压缸活塞运动方程的数学模型;构建了液压控制系统的AMESim仿真模型,设置了模型参数及仿真参数。以典型的正弦曲线液压源信号及激励电磁阀信号变化仿真研究工作制动液压控制系统响应性能,以阶跃开关信号突然开启模拟分析紧急制动液压系统响应。得到了工作制动及紧急制动过程中液压控制系统主要阀口处液压动态响应曲线,仿真结果与实际运行情况相符。该仿真分析为修井机液压盘式刹车液压控制系统性能的改进与完善提供了参考。

  7. Aircraft Hydraulic Systems Dynamic Analysis


    4400 PSIG OUTLET PRESSURE ~’f UM5 S1 l .( FIF ~0RV lR 1 .I. AP (c R (V) IFWM) APPROX C ASE !VPý :iI S ReUN N•;MRF.. r p kN i t, isI A! f IN, I:E • ’l...and 1F.GI pump modelo were assumed from data supplied by CECO. 165 _ -- --- - SECTION V HYDRAULIC MOTOR MODEL DEVELOPMENT AND VERIFICATION A fixed...3 70 P.,0 601 ~4 M24.0 3 1p ’, 4 r I 1 1 ISIS 2411 APPENDIX E (CONT.) HSFR TECHNICAL MANUAL (AFAPL-TR-76-43, VOL. IV) 4.15 VANE PU`MP SUBROUTINE 4.15A

  8. 风轮机液压制动控制系统的研究%Research on Hydraulic Braking Control System of Wind Turbine



    该文分析了风轮机常用的制动系统和控制系统,设计了基于紧急情况下的风轮机液压制动系统,并通过实验进行了测试,最后进行了紧急情况下的数据仿真研究,指出本制动器在不同最大设置压力和初始转速条件下的制动性能。%This paper analyses common braking system and control system in wind turbine, designs the hydraulic brake system of wind tur-bine based on emergency cases,and verified by experiment, also studies on the data simulation in case of emergency, points out the brake performance at different maximum set pressure and initial speed conditions.

  9. FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems

    Wu, Yulin; Wang, Zhengwei; Liu, Shuhong; Yuan, Shouqi; Luo, Xingqi; Wang, Fujun


    was molded into a polytechnic institute focusing on engineering in the nationwide restructuring of universities and colleges undertaken in 1952. At present, the university has 14 schools and 56 departments with faculties in science, engineering, humanities, law, medicine, history, philosophy, economics, management, education and art. The University now has over 25 900 students, including 13 100 undergraduates and 12 800 graduate students. As one of China's most renowned universities, Tsinghua has become an important institution for fostering talents and scientific research. The International Association of Hydro-Environment Engineering and Research (IAHR) particularly promotes the advancement and exchange of knowledge through working groups, specialty symposia, congresses, and publications on water resources, river and coastal hydraulics, risk analysis, energy, environment, disaster prevention, and industrial processes. The IAHR Committee on Hydraulic Machinery and Systems deals with the advancement of technology associated with the understanding of steady and unsteady flow characteristics in hydraulic machinery and conduit systems connected to the machinery. The technology elements include the fluid behaviour within machine components, hydro-elastic behaviour of machine components, cavitation and two phase flow in turbines and pumps, hydraulic machine and plant control systems, the use of hydraulic machines to improve water quality, and even considerations to improve fish survival in their passage through hydro plants. The main emphases of the IAHR Committee on Hydraulic Machinery and Systems are to stimulate research and understanding of the technologies associated with hydraulic machinery and to promote interaction between the machine designers, machine users, the academic community, and the community as a whole. Hydraulic machinery is both cost effective and environmentally friendly. The goals of the IAHR Committee on Hydraulic Machinery and Systems are to improve

  10. Hydraulics.

    Decker, Robert L.; Kirby, Klane

    This curriculum guide contains a course in hydraulics to train entry-level workers for automotive mechanics and other fields that utilize hydraulics. The module contains 14 instructional units that cover the following topics: (1) introduction to hydraulics; (2) fundamentals of hydraulics; (3) reservoirs; (4) lines, fittings, and couplers; (5)…

  11. Aircraft Hydraulic System Leakage Detection and Servicing Recommendations Method


    accumulators, filters, and consumers, that include all the actuators connected to the hydraulic power such as flight controls , brake and landing...Conference, October 4-8 Calgary, Alberta, Canada. Merrit, H. E., (1967), Hydraulic Control Systems. New York: John Willey & Sons. Vianna, W. O. L...2008), Modelagem e Análise do Sistema Hidráulico de uma Aeronave Comercial Regional. M.Sc. Thesis. Instituto Tecnológico de Aeronáutica, São José

  12. Microcomputer Control of a Hydraulic Power Element.


    Electrohydraulic (EHD) Servovalves .................... 9 3. Advantages of EHD Servovalves .......................................... 10 4. Control System Types ................................. 10...positional control with less error. [Ref. 3:pp. 1-21 4. Control System Types Control systems are the means by which servovalves can be used to obtain a

  13. Flight Worthiness of Fire Resistant Hydraulic Systems. Volume 1.


    Phosphonitrilic Fluoroelastomer (PNF); Ethylene Propylene Diene Monomer ( EPDM )* Fliaht Worthiness of Fire Resistant Hydraulic Systems (FWFRHS). Block 19...Exchanger Requirements . 214 Stabilator Stiffness .... 214 Final Weight Impact Results . . . . . . . . . . . 223 2.4 TASK 12...ILLUSTRATIONS (Continued) Figure Page 20 Pressure Loss Distribution - Flight Control Subsystem ..................... 26 21 F-15 R/H Stabilator Actuator

  14. Design and Implementation of New Type Hydraulic Turret Control System%新型液压刀塔控制系统的设计与实现

    马潮; 张文洁; 夏宏


    针对目前国内中低档电动刀架的不足,介绍了以FANUC 0i数控系统PMC为控制核心、DTY63型液压刀塔为控制对象的控制系统的软硬件设计与实现方法。该系统结构简单、效率高、灵活性强、能很好的适应国内中端市场需求。%Aiming at the shortage of current middle and low lever electric turret, this paper introduces the software and hardware de-sign and implementation method of the control system, in which Fanuc 0i numerical control system PMC is taken as the control core to control DTY63 hydraulic turret. The system has the advantages of simple structure, high efficiency and flexibility, which can be a-dapted to internal mid-range market.

  15. A Hydraulic Blowdown Servo System For Launch Vehicle

    Chen, Anping; Deng, Tao


    This paper introduced a hydraulic blowdown servo system developed for a solid launch vehicle of the family of Chinese Long March Vehicles. It's the thrust vector control (TVC) system for the first stage. This system is a cold gas blowdown hydraulic servo system and consist of gas vessel, hydraulic reservoir, servo actuator, digital control unit (DCU), electric explosion valve, and pressure regulator etc. A brief description of the main assemblies and characteristics follows. a) Gas vessel is a resin/carbon fiber composite over wrapped pressure vessel with a titanium liner, The volume of the vessel is about 30 liters. b) Hydraulic reservoir is a titanium alloy piston type reservoir with a magnetostrictive sensor as the fluid level indicator. The volume of the reservoir is about 30 liters. c) Servo actuator is a equal area linear piston actuator with a 2-stage low null leakage servo valve and a linear variable differential transducer (LVDT) feedback the piston position, Its stall force is about 120kN. d) Digital control unit (DCU) is a compact digital controller based on digital signal processor (DSP), and deployed dual redundant 1553B digital busses to communicate with the on board computer. e) Electric explosion valve is a normally closed valve to confine the high pressure helium gas. f) Pressure regulator is a spring-loaded poppet pressure valve, and regulates the gas pressure from about 60MPa to about 24MPa. g) The whole system is mounted in the aft skirt of the vehicle. h) This system delivers approximately 40kW hydraulic power, by contrast, the total mass is less than 190kg. the power mass ratio is about 0.21. Have finished the development and the system test. Bench and motor static firing tests verified that all of the performances have met the design requirements. This servo system is complaint to use of the solid launch vehicle.

  16. Experimental Investigation on the Basic Law of Hydraulic Fracturing After Water Pressure Control Blasting

    Huang, Bingxiang; Li, Pengfeng; Ma, Jian; Chen, Shuliang


    Because of the advantages of integrating water pressure blasting and hydraulic fracturing, the use of hydraulic fracturing after water pressure control blasting is a method that is used to fully transform the structure of a coal-rock mass by increasing the number and range of hydraulic cracks. An experiment to study hydraulic fracturing after water pressure blasting on cement mortar samples (300 × 300 × 300 mm3) was conducted using a large-sized true triaxial hydraulic fracturing experimental system. A traditional hydraulic fracturing experiment was also performed for comparison. The experimental results show that water pressure blasting produces many blasting cracks, and follow-up hydraulic fracturing forces blasting cracks to propagate further and to form numerous multidirectional hydraulic cracks. Four macroscopic main hydraulic cracks in total were noted along the borehole axial and radial directions on the sample surfaces. Axial and radial main failure planes induced by macroscopic main hydraulic cracks split the sample into three big parts. Meanwhile, numerous local hydraulic cracks were formed on the main failure planes, in different directions and of different types. Local hydraulic cracks are mainly of three types: local hydraulic crack bands, local branched hydraulic cracks, and axial layered cracks. Because local hydraulic cracks produce multiple local layered failure planes and lamellar ruptures inside the sample, the integrity of the sample decreases greatly. The formation and propagation process of many multidirectional hydraulic cracks is affected by a combination of water pressure blasting, water pressure of fracturing, and the stress field of the surrounding rock. To a certain degree, the stress field of surrounding rock guides the formation and propagation process of the blasting crack and the follow-up hydraulic crack. Following hydraulic fracturing that has been conducted after water pressure blasting, the integrity of the sample is found to

  17. Application of PID Control in Hydraulic Elevator Speed Feedback Control System%PID控制在液压电梯速度反馈控制系统中的应用



    According to the nonlinear mathematical model of hydraulic elevator, it was very difficult to use mechanism model directly, and cannot get the controlling mathematical model.Therefore, identification method was used to set up the model. Secondly, the PID controller was designed, and the transfer function for the speed feedback control system of hydraulic eleva-tor was theoretically deduced, and the value range of the PID controller parameters was given.Finally, the Simulink model of hydraulic elevator was established, and the effectiveness and feasibility of PID control algorithm were verified.%针对液压电梯的非线性数学模型,直接用机理建模非常困难,得不到可用于控制的数学模型。因此采用辨识方法建立模型。其次,设计了PID控制器,理论上推导了液压电梯速度反馈控制系统的传递函数,并给出了PID控制参数的取值范围。最后,建立了液压电梯的Simulink模型,验证了PID控制算法的有效性和可行性。

  18. The dynamic running law study on driving system of hydraulic winder

    彭佑多; 刘德顺; 郭迎福; 张永忠; 文西芹


    Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist driver. The paper studies the dynamic running law of hydraulic driving system, analyses the influence of driver operating speed on the dynamic running characteristic, and points out the reasonable driver operating speed to control the dynamic stress in rope and to reduce the oscillation of rope system.

  19. Chapter 12. Pure Tap Water Hydraulic Systems and Applications

    Conrad, Finn; Adelstorp, Anders


    Presentation of developed a modern pure tap water hydraulic components (Nessie), systems and industrial applications.......Presentation of developed a modern pure tap water hydraulic components (Nessie), systems and industrial applications....

  20. 液压系统流量PID闭环控制实验研究%Study on Closed Loop Control Experiment of Hydraulic System Flow PID

    刘永; 杨彬


    为了提高液压系统的流量控制精度,消除稳态误差,设计了流量PID闭环控制系统。通过在Labview软件中编制测控程序,将实测流量值与目标值的差值输入PID控制器,通过PID控制器输出的转速控制电压调整伺服电机转速,从而使实际输出流量达到目标设定值。实验结果表明:实际输出流量值能很好地跟随、响应目标流量值变化;流量闭环控制系统对阶跃、正弦、斜坡压力干扰信号的校正能力较强。%In order to improve the flow control precision of hydraulic system and eliminate the steady-state error, the flow PID closed loop control system was designed. Through the measurement and control program written in Labview software, the difference between flow measurement value and the target value was inputted the PID controller. The speed control voltage of servo motor PID controller was outputted through PID controller. By adjusting the rotational speed of servo motor, the actual output flow can reach the set value. The experimental results show that the actual flow value can follow and respond to the change of target flow. The flow closed loop control system has strong anti interference ability for the step, sine and slope pressure disturbance signal.

  1. 数控机床液压系统的可靠性验证试验方法%Reliability Validation Test for Hydraulic System of Numerical Control Machine



    根据数控机床液压系统的主要故障模式,建立液压系统的可靠性模型,给出液压系统的可靠性特征量;基于可靠性试验的基本思路,提出数控机床液压系统的可靠性试验方法并给出示例,为数控机床液压系统的可靠性验证试验提供技术途径.%The functions, principles and main failure modes of hydraulic system of numerical control machine were introduced. A reliability model for this type of hydraulic system was established. Reliability characteristic parameters of this hydraulic system were given. Based on the idea of characteristic parameter measurement, the reliability test methods of the hydraulic system were put forward. An application example was given. The research work provides technology way for reliability validation test methods of the hydraulic system of numerical control machine.

  2. Design of a pictogram of the operator-hydraulic filler system

    Bukhgol' ts, V.P.; Dinershtein, V.A.


    A modern hydraulic filling system is discussed which consists of two lines: the crusher and sorter preparing the filling material, and the hydraulic filling unit, which includes a mixer and a system of pulp conduits. The process chart of the hydraulic filling system without the crusher-sorter is illustrated. When the system is started, water is first flushed through the pulp conduit, gate valves with drives are opened, and the quantity of water discharged is measured by water output sensors. For effective and failure-free operation of the system, remote control and monitoring elements are introduced into the hydraulic filling system.

  3. 14 CFR 33.72 - Hydraulic actuating systems.


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function properly under all conditions in which...



    A new typed hydraulic system of electro-hydraulic hammer is researched and developed.By means of power bond graphs the modeling and simulation to the dynamic characteristics of the new hydraulic system are performed. The experimental research which is emphasized on the blowing stroke is also performed. It is proved from the result of simulation and experiment that this new hydraulic system possesses such advantages as simplification of structure,flexibleness of operation and reliability of working. Especially it possesses better dynamic characteristics.

  5. Method for reducing excess heat supply experienced in typical Chinese district heating systems by achieving hydraulic balance and improving indoor air temperature control at the building level

    Zhang, Lipeng; Gudmundsson, Oddgeir; Thorsen, Jan Eric;


    that once the hydraulic balance is achieved and indoor temperatures are controlled with this integrated approach, 17% heat savings and 42.8% pump electricity savings can be achieved. The energy savings will also have a positive environmental effect with seasonal reductions of 11 kg CO2, 0.1 kg SO2, and 0...... with the actual heat demand. This results in 15-30% of the total supplied heat being lost. This paper proposes an integrated approach that aims to reduce the excess heat loss by introducing pre-set thermostatic radiator valves combined with automatic balancing valves. Those devices establish hydraulic balance...

  6. Composition of Multiplex Electro-Hydraulic Control System and Operation Modes%电液复合式控制系统的组成及分析工况

    胡雪峰; 封延松


    介绍了水下生产系统的控制类型,重点分析了电液复合式系统构成及原理.定义了电液复合式液压系统的分析工况.为了降低控制系统的风险,减少制造及测试的成本,采用了液压仿真模拟软件建立水下生产控制系统的模型,进而确定合适的设备参数.介绍了南海某气田的液压系统模拟仿真分析结果,目前该气田工程项目已进入采购阶段.这一结果对于其他项目的液压系统分析具有重要参考价值.%The types of subsea control system is introduced, the composition of multiplex electro hydraulic controls and hydraulic system's operation modes are defined. In order to reduce the risk and the test cost of hydraulic system, the subsea production control system model is established using hydraulic simulation software to determine the appropriating device parameters. The simulation result of a hydraulic system in a gas field of South China Sea is got, now the field is in the procurement stage. The result will be helpful in the simulation of other project's hydraulic system.

  7. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole;


    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable......Currently mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are becoming standard on a high number of machines, hereby replacing hydraulic pilot lines and offering new possibilities with regard to both control and feasibility. As most open...... displacement pump based on an electrical reference. The paper first presents the considered system and an experimentally verified model of this. A linearized model and a stability analysis is then presented, based on which an H∞control strategy is selected. A nominal performance and a robustly stable...


    Xu Bing; Ma Jien; Lin Jianjie


    The computational flow rate feedback and control method, which can be used in proportional valve controlled hydraulic elevators, is discussed and analyzed. In a hydraulic elevator with this method, microprocessor receives pressure information from the pressure transducers and computes the flow rate through the proportional valve based on pressure-flow conversion real time algorithm. This hydraulic elevator is of lower cost and energy consumption than the conventional closed loop control hydraulic elevator whose flow rate is measured by a flow meter. Experiments are carried out on a test rig which could simulate the load of hydraulic elevator. According to the experiment results, the means to modify the pressure-flow conversion algorithm are pointed out.

  9. Controlling a negative loaded hydraulic cylinder using pressure feedback

    Hansen, M.R.; Andersen, T.O.


    This paper is concerned with the inherent oscillatory nature of pressure compensated velocity control of a hydraulic cylinder subjected to a negative load and suspended by means of an over-center valve. Initially, a linearized stability analysis of such a hydraulic circuit is carried out clearly...

  10. PLC control system of 1600-ton hydraulic pressure machine for abrasive products%1600吨磨料制品液压机的PLC控制



    针对继电器控制的大型砂轮成型设备,1600吨液压机电气线路复杂和故障率高的状况,采用三菱FX2N系列的可编程逻辑控制器对原有的继电器控制系统进行改造,以软继电器的逻辑运算取代传统继电器的硬线连接;运用PLC的顺序控制设计法,并按照工艺流程,以输出元件的变化设计控制功能图和梯形图,简化了线路;采用硬件软件双重联锁提高了控制系统的可靠性.%In order to remedy the complex electrical circuits and high failure rate with the large wheel molding equipment of 1600 tons hydraulic pressure machines, which were controlled by relay, MITSUBISHI FX2N programmable logical controller was adopted to replace the original relay control system. The traditional relay's hard-wired connections were replaced by logical operation of soft relay. What's more, PLC sequential control method was adopted and circuits were simplified by changing design control function diagram and ladder chart of the output components according to the technological process. The reliability of the control system was improved with double chain of hardware and software.

  11. A novel energy recovery system for parallel hybrid hydraulic excavator.

    Li, Wei; Cao, Baoyu; Zhu, Zhencai; Chen, Guoan


    Hydraulic excavator energy saving is important to relieve source shortage and protect environment. This paper mainly discusses the energy saving for the hybrid hydraulic excavator. By analyzing the excess energy of three hydraulic cylinders in the conventional hydraulic excavator, a new boom potential energy recovery system is proposed. The mathematical models of the main components including boom cylinder, hydraulic motor, and hydraulic accumulator are built. The natural frequency of the proposed energy recovery system is calculated based on the mathematical models. Meanwhile, the simulation models of the proposed system and a conventional energy recovery system are built by AMESim software. The results show that the proposed system is more effective than the conventional energy saving system. At last, the main components of the proposed energy recovery system including accumulator and hydraulic motor are analyzed for improving the energy recovery efficiency. The measures to improve the energy recovery efficiency of the proposed system are presented.

  12. 水下生产设施液压控制仿真系统%Simulation system of subsea hydraulic control kit

    周美珍; 高明; 王宇臣; 杜浩博


    为解决水下生产设施液压控制系统设计过程繁琐等问题,将AMESim软件的液压仿真技术与Visual Basic软件设计技术相结合,并将之应用于参数校核和系统仿真分析中.开展了对水下生产液压控制系统的工作原理以及组成元件的分析,建立了辅助软件设计与基本设计思路之间的关系,提出了水下生产设施液压控制仿真系统;在AMESim环境下开发了一套针对水下生产系统的液压元件库,实现了仿真领域的专业性;同时在Visual Basic程序开发上,根据设计人员输入的参数,校核相关标准,并将计算与输入的数据自动导入至AMESim仿真系统中,实现了水下生产系统仿真的过程控制;在中国海洋石油公司的一个项目中对辅助设计软件的功能和操作进行了评估.测试结果表明,针对水下生产设施液压控制仿真系统的设计开发可为相关设计人员提供界面友好、操作清晰的设计平台.%In order to solve the trivial problems in the hydraulic control system design of subsea production, the technology of AMESim's hydraulic simulation and Visual Basic software designing were investigated. After the analysis of the working principle of the system and its components, the relationship between software designing and methodology of the system was established, and the development of the simulation system was raised. The library development of subsea hydraulic components with the help of AMESim was achieved in specificity of simulation. Referred to the aided software designing with Visual Basic, the process control in the subsea production system simulation was succeeded, which covers the computation of required standard based on the users input and loads the parameters into the simulation system in AMESim automatically. The test result for the assistant software in one project of CNOOC indicates that the software provides a convenient platform for designers of subsea production system with

  13. Dynamic characteristics of hydraulic power steering system with accumulator in load-haul-dump vehicle

    杨忠炯; 何清华; 柳波


    Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle were simulated and discussed with SIMULINK software and hydraulic control theory. The results show that the dynamic characteristics of hydraulic power steering system are improved obviously by using bladder accumulator, the hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle generates vibration at the initial stage under the normal steering condition of pulse input, and its static response time is 0.25 s shorter than that without bladder accumulator. Under the normal steering working condition, the capacity of steering accumulator for absorbing pulse is directly proportional to the cross section area of connecting pipeline, and inversely proportional to the length of connecting pipeline. At the same time, the precharge pressure of nitrogen in steering accumulator should be 60%- 80% of the rated minimum working pressure of hydraulic power steering system. Under the abnormal steering working condition, the steering cylinder piston may obtain higher motion velocity, and the dynamic response velocity of hydraulic power steering system can be increased by reducing the pressure drop of hydraulic pipelines between the accumulator and steering cylinder and by increasing the rated pressure of hydraulic power steering system, but the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle have nothing to do with the precharge pressure of nitrogen in steering accumulator.

  14. Application of multi-objective controller to optimal tuning of PID gains for a hydraulic turbine regulating system using adaptive grid particle swam optimization.

    Chen, Zhihuan; Yuan, Yanbin; Yuan, Xiaohui; Huang, Yuehua; Li, Xianshan; Li, Wenwu


    A hydraulic turbine regulating system (HTRS) is one of the most important components of hydropower plant, which plays a key role in maintaining safety, stability and economical operation of hydro-electrical installations. At present, the conventional PID controller is widely applied in the HTRS system for its practicability and robustness, and the primary problem with respect to this control law is how to optimally tune the parameters, i.e. the determination of PID controller gains for satisfactory performance. In this paper, a kind of multi-objective evolutionary algorithms, named adaptive grid particle swarm optimization (AGPSO) is applied to solve the PID gains tuning problem of the HTRS system. This newly AGPSO optimized method, which differs from a traditional one-single objective optimization method, is designed to take care of settling time and overshoot level simultaneously, in which a set of non-inferior alternatives solutions (i.e. Pareto solution) is generated. Furthermore, a fuzzy-based membership value assignment method is employed to choose the best compromise solution from the obtained Pareto set. An illustrative example associated with the best compromise solution for parameter tuning of the nonlinear HTRS system is introduced to verify the feasibility and the effectiveness of the proposed AGPSO-based optimization approach, as compared with two another prominent multi-objective algorithms, i.e. Non-dominated Sorting Genetic Algorithm II (NSGAII) and Strength Pareto Evolutionary Algorithm II (SPEAII), for the quality and diversity of obtained Pareto solutions set. Consequently, simulation results show that this AGPSO optimized approach outperforms than compared methods with higher efficiency and better quality no matter whether the HTRS system works under unload or load conditions.

  15. Pollution Type and Control Ways of Hydraulic System of Civil Airplane%民机液压系统污染种类以及控制方法



    介绍了液压系统的集中污染源,分析了污染源造成的原因并采取了相应的控制措施。%This paper mainly analyzed the pollution sources in the hydraulic system of civil airplane ,found out the reasons ,and put forword the relevant measures .

  16. Modeling, Optimization & Control of Hydraulic Networks

    Tahavori, Maryamsadat


    to check if the network is controllable. Afterward the pressure control problem in water supply systems is formulated as an optimal control problem. The goal is to minimize the power consumption in pumps and also to regulate the pressure drop at the end-users to a desired value. The formulated optimal...... in water network is pressure management. By reducing the pressure in the water network, the leakage can be reduced significantly. Also it reduces the amount of energy consumption in water networks. The primary purpose of this work is to develop control algorithms for pressure control in water supply...... systems. To have better understanding of water leakage, to control pressure and leakage effectively and for optimal design of water supply system, suitable modeling is an important prerequisite. Therefore a model with the main objective of pressure control and consequently leakage reduction is presented...

  17. Modeling and control for hydraulic transmission of unmanned ground vehicle

    王岩; 张泽; 秦绪情


    Variable pump driving variable motor (VPDVM) is the future development trend of the hydraulic transmission of an unmanned ground vehicle (UGV). VPDVM is a dual-input single-output nonlinear system with coupling, which is difficult to control. High pressure automatic variables bang-bang (HABB) was proposed to achieve the desired motor speed. First, the VPDVM nonlinear mathematic model was introduced, then linearized by feedback linearization theory, and the zero-dynamic stability was proved. The HABB control algorithm was proposed for VPDVM, in which the variable motor was controlled by high pressure automatic variables (HA) and the variable pump was controlled by bang-bang. Finally, simulation of VPDVM controlled by HABB was developed. Simulation results demonstrate the HABB can implement the desired motor speed rapidly and has strong robustness against the variations of desired motor speed, load and pump speed.

  18. Software Implementation of Hydraulic Cylinder Position PID Closed Loop Control in Proportional Valve Control System Using PLC%比例阀控液压缸位置PID闭环控制的PLC软件实现

    李艳杰; 崔天宇; 王海; 马鹤; 苗鑫超


    A software implementation method of hydraulic cylinder position PID closed loop control in proportional valve control system using Siemens S7-200 was proposed.The block diagram and ladder program was given,and experimental studies in Festo TP701 proportional hydraulic test bed was done.Experimental studies have shown that the proportion of open-loop control system,using software methods can achieve the closed-loop control of position and other physical quantities,to control the performance of precision and anti-jamming capability to meet the demand of general industrial applications.%提出一种利用西门子S7-200实现比例阀控制系统中液压缸位置PID闭环控制的软件实现方法,给出了程序框图及梯形图程序,并在Festo TP701比例液压试验台上进行实验研究.实验研究表明,开环比例控制系统中,利用软件的方法可实现位置等物理量的闭环控制,控制精度和抗干扰能力等性能可满足一般工业应用的需求.

  19. Hydraulic power take-off for wave energy systems

    Christensen, Georg Kronborg


    Investigation and laboratory experiments with a hydraulic power conversion system for converting forces from a 2.5m diamter float to extract energy from seawaves. The test rig consists of a hydraulic wave simulator and a hydraulic point absorber. The absorber converts the incomming forces...

  20. Robust Force Control of a 6-Link Electro-Hydraulic Manipulator

    Ahn, Kyoungkwan; Yokota, Shinichi

    Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. This maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulator because hydraulic manipulators have the advantage of electric insulation and power/mass density. Meanwhile an electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and its parameter fluctuations are greater than those of an electrically driven manipulator. So it is relatively difficult to realize not only stable contact work but also accurate force control for the autonomous assembly tasks using hydraulic manipulators. In this paper, the robust force control of a 6-link electro-hydraulic manipulator system used in the real maintenance task of active electic line is examined in detail. A nominal model for the system is obtained from experimental frequency responses of the system, and the deviation of the manipulator system from the nominal model is derived by a multiplicative uncertainty. Robust disturbance observers for force control are designed using this information in an H∞ framework, and implemented on the two different setups. Experimental results show that highly robust force tracking by a 6-link electro-hydraulic manipulator could be achieved even if the stiffness of environment and the shape of wall change.

  1. Dynamic simulation and optimal control strategy for a parallel hybrid hydraulic excavator

    Xiao LIN; Shuang-xia PAN; Dong-yun WANG


    The primary focus of this study is to investigate the control strategies of a hybrid system used in hydraulic excavators. First, the structure and evaluation target of hybrid hydraulic excavators are analyzed. Then the dynamic system model including batteries, motor and engine is built as the simulation environment to obtain control results. A so-called multi-work-point dynamic control strategy, which has both closed-loop speed PI (proportion integral) control and direct torque control, is proposed and studied in the simulation model. Simulation results indicate that the hybrid system with this strategy can meet the power demand and achieve better system stability and higher fuel efficiency.

  2. Study on Hydraulic Control System of Rolling Mill Based on LabVIEW%基于LabVIEW的轧钢机液压控制系统研究

    李文华; 张建卓; 李康康


    提出一种基于LabVIEW控制高速阀全开占空比,通过LabVIEW实时采集辊缝大小以作为反馈控制,同采集到的温度信号参数一起作为输入量,对轧钢机辊缝进行精确控制的思想.设计了流量控制策略与算法,并开发了LabVIEW程序框图和前面板.测试结果表明:高速阀全开过程中流过高速阀的液压油体积与实际所需的液压油体积拟合精度高,且形成了控制轧钢机辊缝的闭环控制系统.%A thought of controlling roll gap of rolling mill by controlling the duty cycle of full open of high-speed valve and collecting the roll gap as a feedback control together with the temperature signal as the input based on LabVIEW was proposed. The strategy and algorithm were designed. The LabVIEW block diagram and front panel were developed. The experiment shows that the volume of hydraulic oil flowing through the valve in the full open is closed to the practical required. And a closed-loop controlling system of controlling the roll gap of the rolling mill is formed.

  3. The impact research of control modes in steam turbine control system (digital electric hydraulic to the low-frequency oscillation of grid

    Yanghai Li


    Full Text Available Through the analysis of the control theory for steam turbine, the transfer function of the steam turbine control modes in the parallel operation was obtained. The frequency domain analysis indicated that different control modes of turbine control system have different influence on the damping characteristics of the power system. The comparative analysis shows the direction and the degree of the influence under the different oscillation frequency range. This can provide the theory for the suppression of the low-frequency oscillation from turbine side and has a guiding significance for the stability of power system. The results of simulation tests are consistent with the theoretic analysis.

  4. Thermal-hydraulic modeling and analysis of hydraulic system by pseudo-bond graph

    胡均平; 李科军


    To increase the efficiency and reliability of the thermodynamics analysis of the hydraulic system, the method based on pseudo-bond graph is introduced. According to the working mechanism of hydraulic components, they can be separated into two categories: capacitive components and resistive components. Then, the thermal-hydraulic pseudo-bond graphs of capacitive C element and resistance R element were developed, based on the conservation of mass and energy. Subsequently, the connection rule for the pseudo-bond graph elements and the method to construct the complete thermal-hydraulic system model were proposed. On the basis of heat transfer analysis of a typical hydraulic circuit containing a piston pump, the lumped parameter mathematical model of the system was given. The good agreement between the simulation results and experimental data demonstrates the validity of the modeling method.

  5. 挖掘机正流量泵控液压系统的特性分析%Analysis on positive flow pump control system of hydraulic excavator

    贾文华; 殷晨波; 曹东辉; 陈克雷


    采用泵控挖掘机液压系统特性分析方法,在分析泵的输出特性的基础上,给出确定先导压力信号和控制泵排量的方法,并对泵的输出特性进行了仿真和实验研究.结果表明:正流量控制下,泵的排量由执行器流量需求和油泵的p-Q曲线动态实时调节,系统具有良好的负载流量适应性和负载敏感性,其液压系统中不存在负压,只有约0.5 MPa的背压,回油功率损失几乎为0.%Some problems were studied for the positive flow control of pump system of hydraulic excavator. Based on the analysis of pump output characteristics, the control method for pilot pressure and the pump displacement was given. The pump output characteristics were investigated by simulation and experiment. Results showed that flow was adjusted by flow required by actuator and the p - Q curve of main pump. For the positive system, the excavator had good load flow adaptability and load sensitivity. The power loss of returning oil path was almost zero. In the returning path, the negative pressure was only 0.5 Mpa for the positive system.

  6. General Predictive Control of Electro-hydraulic Position Servo System of Precise Straightening Press%精校机电液位置伺服系统的广义预测控制

    陈永新; 柯尊忠; 伍德林


    The discrete mathematical modal of electro-hydraulic position servo system for precise straightening press was built.A method of general predictive control of the electro-hydraulic position servo system of the precise straightening press was presented by applying theory of general predictive control.The simulation result shows that control precision and tracking performance of the system are improved greatly.%建立精密校直液压机(精校机)电液位置伺服系统离散数学模型,将广义预测控制理论应用于精校机电液位置伺服系统中,提出精校机电液位置伺服系统的广义预测控制方法.仿真结果表明,系统的跟踪性能良好、控制精度提高.

  7. Simulation of Open Loop and Closed Loop Control of Hydraulic Thrust System of Shield Machine%盾构推进液压系统的开环与闭环仿真控制

    徐尤南; 邓文强


    In this paper ,the hydraulic cylinder of shield thrust system is controlled by partition ,to reduce the complexity of the system and ensure the accuracy of control . The simulation analysis on the thrust hydraulic system is carried out by hydraulic simulation software AMESim ,which is controlled by open loop and closed loop respectively .The results show that :compared with open loop control , the pressure-flow closed loop control can effectively reduce the pressure and flow fluctuations , control the pressure and velocity in real time ,the control effect is better .%对盾构推进系统的液压缸采用分区控制,以达到降低系统复杂程度、保证控制精度的目的。用液压仿真软件AM ESim对推进液压系统进行仿真模拟分析,采用开环与闭环两种方式。仿真结果表明,压力流量闭环控制较开环控制可以有效减少压力和流量的波动,实时控制推进压力和推进速度,控制效果较好。

  8. The Development of an Optimal Control Strategy for a Series Hydraulic Hybrid Vehicle

    Chih-Wei Hung


    Full Text Available In this work, a Truck Class II series hydraulic hybrid model is established. Dynamic Programming (DP methodology is applied to derive the optimal power-splitting factor for the hybrid system for preselected driving schedules. Implementable rules are derived by extracting the optimal trajectory features from a DP scheme. The system behaviors illustrate that the improved control strategy gives a highly effective operation region for the engine and high power density characteristics for the hydraulic components.

  9. An approach for second order control with finite time convergence for electro-hydraulic drives

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.


    Being a second order sliding algorithm, the super twisting algorithm is highly attractive for application in control of hydraulic drives and mechanical systems in general, as it utilizes only the control error while driving the control error as well as its derivative to zero for properly chosen...... algorithm parameters. However a discontinuous term internally in the control structure may excite pressures of transmission lines in hydraulic drives as the control structure strives to maintain the control error and its derivative equal to zero. In this paper a modified version of a controller based...

  10. Intelligent Control of a Novel Hydraulic Forging Manipulator

    J. Wang


    Full Text Available The increased demand for large-size forgings has led to developments and innovations of heavy-duty forging manipulators. Besides the huge carrying capacity, some robot features such as force perception, delicacy and flexibility, forging manipulators should also possess. The aim of the work is to develop a heavy-duty forging manipulator with robot features by means of combination of methods in mechanical, hydraulic, and control field. In this paper, through kinematic analysis of a novel forging manipulator, control strategy of the manipulator is proposed considering the function and motion of forging manipulators. Hybrid pressure/position control of hydraulic actuators in forging manipulator is realized. The feasibility of the control method has been verified by the experiments on a real prototype of the novel hydraulic forging manipulator in our institute. The intelligent control of the forging manipulator is performed with programmable logic controller which is suitable for industrial applications.

  11. Parametric adaptive estimation and backstepping control of electro-hydraulic actuator with decayed memory filter.

    Guo, Qing; Sun, Ping; Yin, Jing-Min; Yu, Tian; Jiang, Dan


    Some unknown parameter estimation of electro-hydraulic system (EHS) should be considered in hydraulic controller design due to many parameter uncertainties in practice. In this study, a parametric adaptive backstepping control method is proposed to improve the dynamic behavior of EHS under parametric uncertainties and unknown disturbance (i.e., hydraulic parameters and external load). The unknown parameters of EHS model are estimated by the parametric adaptive estimation law. Then the recursive backstepping controller is designed by Lyapunov technique to realize the displacement control of EHS. To avoid explosion of virtual control in traditional backstepping, a decayed memory filter is presented to re-estimate the virtual control and the dynamic external load. The effectiveness of the proposed controller has been demonstrated by comparison with the controller without adaptive and filter estimation. The comparative experimental results in critical working conditions indicate the proposed approach can achieve better dynamic performance on the motion control of Two-DOF robotic arm.

  12. 基于Matlab/Simulink的高速液压动力系统闭环控制研究%Research on Closed Loop Control for High-speed Hydraulic Power System Based on Matlab/Simulink

    王继哲; 赵月琴; 张士卫


    High-speed hydraulic power system applied in some mechanical ejector is used to lauch load fastly. By the designed closed loop control system, ejection parameters were controlled within a certain range. Matlab/Simulink was applied to conduct theoretical analysis, modeling and simulation of the control system based on high-speed hydraulic power system design scheme. The simulation results were analyzed and the reasons were found. It provides theoretical basis for the engineering realization of high-speed hydraulic power system.%应用于某机械弹射器的高速液压动力系统用于负载的高速弹射,通过设计的闭环控制系统可实现一定范围内的弹射参数控制.在高速液压动力系统设计方案的基础上,运用Matlab/Simulink对控制系统进行了理论分析、建模和仿真.对仿真结果进行分析,找出影响仿真结果的原因,为高速液压动力系统的工程实现提供理论依据.

  13. Design Rules for High Damping in Mobile Hydraulic Systems

    Axin, Mikael; Krus, Petter


    This paper analyses the damping in pressure compensated closed centre mobile working hydraulic systems. Both rotational and linear loads are covered and the analysis applies to any type of pump controller. Only the outlet orifice in the directional valve will provide damping to a pressure compensated system. Design rules are proposed for how the system should be dimensioned in order to obtain a high damping. The volumes on each side of the load have a high impact on the damping. In case of a ...

  14. Sliding Control with Chattering Elimination for Hydraulic Drives

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.;


    This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load characteri...

  15. Quantized pressure control in large-scale nonlinear hydraulic networks

    Persis, Claudio De; Kallesøe, Carsten Skovmose; Jensen, Tom Nørgaard


    It was shown previously that semi-global practical pressure regulation at designated points of a large-scale nonlinear hydraulic network is guaranteed by distributed proportional controllers. For a correct implementation of the control laws, each controller, which is located at these designated poin

  16. 49 CFR 570.55 - Hydraulic brake system.


    ... parking brake and turn the ignition to start to verify that the brake system failure indicator lamp is... 49 Transportation 6 2010-10-01 2010-10-01 false Hydraulic brake system. 570.55 Section 570.55... 10,000 Pounds § 570.55 Hydraulic brake system. The following requirements apply to vehicles...

  17. The Analysis of Bailing Hydraulic Control System for a Large Extinguishing Aircraft%某灭火型飞机汲水液压控制系统分析

    胡刚; 裴沛


    该文是对某大型灭火飞机汲水液压控制系统的设计进行分析,通过对汲水斗收放时间、收放同步性及外载荷等的计算分析,验证了汲水液压控制系统设计的可行性。%This article is designed to analyze bailing hydraulic control system for a large fire-fighting aircraft, by the time of the bailing buck-et retractable, retractable synchronization and external load calculation and analysis to verify bailing hydraulic control system Feasibility of design.

  18. 25/17MN双动厚板冲压液压机的电气控制系统%Electric control system of 25/17MN double motion hydraulic press punching thick plate



    Electric control system of 25/17MN double motion hydraulic press punching thick plate and parameters operation manner have been introduced with analysis of graphic interface reality.%介绍了25/17MN双动厚板冲压液压机的电气控制系统及其系统中的参数处理方式,并对图形界面的实时性进行了分析。

  19. Parameter Designing for Heave Compensation Hydraulic System Installed in Deepwater

    Zhao Teng


    Full Text Available The function diagram of active heave compensation hydraulic system has been given, besides, the mathematics model for the principal hydraulic components of the compensation system has been built, and the input-output relation between components has been made clear. Aimed at compensating work capacity for the system, design and research on parameters as the bearing pressure, the initial state and the maximum flow of hydraulic cylinder, accumulator and other principal components have been made separately, and standardized design has been accomplished in accordance with relevant standards. Furthermore, calculus and verification for the capacity of the hydraulic system in different working stages have been made in order to calculate the pressure lose of the system and provide objective data for the hardware system design of the hydraulic components of the heave compensation system.

  20. A Study on Control Strategy of Regenerative Braking in the Hydraulic Hybrid Vehicle Based on ECE Regulations

    Tao Liu


    Full Text Available This paper establishes a mathematic model of composite braking in the hydraulic hybrid vehicle and analyzes the constraint condition of parallel regenerative braking control algorithm. Based on regenerative braking system character and ECE (Economic Commission of Europe regulations, it introduces the control strategy of regenerative braking in parallel hydraulic hybrid vehicle (PHHV. Finally, the paper establishes the backward simulation model of the hydraulic hybrid vehicle in Matlab/simulink and makes a simulation analysis of the control strategy of regenerative braking. The results show that this strategy can equip the hydraulic hybrid vehicle with strong brake energy recovery power in typical urban drive state.

  1. 超磁致伸缩电液伺服阀驱动机构控制系统设计%Design of Control System of Giant Magnetostrictive Electro-hydraulic Servo Valve Driven Machine

    杨朝舒; 何忠波; 李冬伟; 薛光明


    为了实现超磁致伸缩电液伺服阀的快速、准确控制,论述了基于PWM控制的超磁致伸缩电液伺服阀的基本结构和工作原理,设计了基于PicoScope2203数字示波器和STC89C51单片机的超磁致伸缩材料电液伺服阀驱动机构的控制系统。结果表明:该控制系统具有控制精度高、控制迅速、集成度高、操作便捷等特点。%In order to achieve the speedy and precision control of electro⁃hydraulic servo valve based on giant magnetostrictive material, the basic structure and working principle of a kind of Electro⁃hydraulic Servo Valve based on giant magnetostrictive material with PWM control was discussed. A control system for the giant magnetostrictive electro⁃hydraulic servo valve driven machine based on PicoScope2203 Digital Oscilloscope and STC89C51 series MCU was designed. The results show that the control system has properties of high speed and precision, highly integrated and convenient for operation, and etc.

  2. Fundamental characteristics of oil hydraulic servo system; Yuatsu servo kei no kihonteki tokusei

    Suzuki, K. [Musashi Instsitute of Technology, Tokyo (Japan)


    Since a hydraulic servo generates a great force very quickly upon receiving a small force or electric power, it is widely used in machine tools, construction machinery, and vehicles. The basics are that a high pressure fluid generated by a hydraulic pump is controlled by a valve and forwarded to a hydraulic cylinder or rotary hydraulic motor for the generation of a parallel motion or rotation. For the control of the valve, there are the mechanical-hydraulic servo mechanism in which the valve is operated by mechanical linkage and the electrical-hydraulic servo system in which the valve is driven by electric signals. It is difficult to perform sophisticated control such as optimum control by use of the mechanical method while the electrical method may be applied to such sophisticated control. In the former, a hydraulic servo system is constructed using mechanical feedback. It is simpler and more reliable than the other, and is used for the control of aircraft wings and for the steering of ships and vehicles. Using the latter, electric signals low in power are amplified in a servo amplifier before being sent to the servo valve. For the driving of the spool in a servo valve, the nozzle and flapper system is widely in use. (NEDO)

  3. Numerical simulation on a throttle governing system with hydraulic butterfly valves in a marine environment

    Wan, Hui-Xiong; Fang, Jun; Huang, Hui


    Hydraulic butterfly valves have been widely applied in marine engineering because of their large switching torque, low pressure loss and suitability for large and medium diameter pipelines. Due to control problems resulting from switching angular speeds of the hydraulic butterfly valve, a throttle-governing control mode has been widely adopted, and detailed analysis has been carried out worldwide on the structural principle concerning speed-regulation and the load torque on the shaft while opening or closing a hydraulic butterfly valve. However relevant reports have yet been published on the change law, the error and the influencing factors of the rotational angular velocity of the hydraulic butterfly valve while opening and closing. In this article, research was based on some common specifications of a hydraulic butterfly valve with a symmetrical valve flap existing in a marine environment. The throttle governing system supplied by the accumulator to achieve the switching of the hydraulic control valve was adopted, and the mathematical models of the system were established in the actual conditions while the numerical simulations took place. The simulation results and analysis show that the rotational angular velocity and the error of the hydraulic butterfly valve while switching is influenced greatly by the drainage amount of the accumulator, resulting in pressure loss in the pipeline, the temperature of hydraulic medium and the load of the hydraulic butterfly valve. The simulation results and analysis provide a theoretical basis for the choice of the total capacity of the accumulator and pipeline diameters in a throttle governing system with a hydraulic butterfly valve. It also determines the type and specification of the hydraulic butterfly valve and the design of motion parameters of the transported fluid.

  4. Application of Ferrography to Fault Diagnosis of Hydraulic Systems


    This paper deals with research on the successful use of ferrography as a wear measurement method for condition monitoring and fault diagnosis of hydraulic systems.The analysis program and progression is discussed, and a case study for condition monitoring and fault diagnosis of hydraulic systems by means of ferrography is also reviewed.

  5. Design of Pumps for Water Hydraulic Systems

    Klit, Peder; Olsen, Stefan; Bech, Thomas Nørgaard


    This paper considers the development of two pumps for water hydraulic applications. The pumps are based on two different working principles: The Vane-type pump and the Gear-type pump. Emphasis is put on the considerations that should be made to account for water as the hydraulic fluid.......KEYWORDS: water, pump, design, vane, gear....

  6. Simulation of hydraulic control system of deepwater subsea blowout preventer stacks%深水防喷器组液压控制系统仿真

    葛斐; 郭宏; 李博; 许征


    井喷是海洋石油安全钻探生产的重要威胁,人为操作失误或元器件失效都可能导致井喷。防喷器组(BOP)安装在水下井口头,是控制井喷的核心部件,一旦发生井喷,BOP控制系统驱动阀门关闭井口,保证油井的安全。研究了深水防喷器组包括其液压控制系统的功能,在系统仿真软件SimulationX中建立防喷器组的详细模型,包括环形防喷器和闸板防喷器及防喷器组的液压控制系统。仿真分析了1524 m水深下防喷器在不同操作顺序下的封井过程,验证了BOP阀门关闭所用时间符合API规范要求,仿真结果与平台实测数据基本吻合。%The oil and gas industry has been constantly affected by numerous blowouts since it was evolved.Blowout which is caused mainly by kick,leads to loss of valuable reserves and also causes property damage along with loss of life.Subsea blowout preventer (BOP)stack is the key equipment which ensures the safety of wel bore operation.Once the blowout occurs,the control system of BOP wil actuate the corresponding valve and close the preventer within a spec-ified time.This paper investigated the dynamic behavior of hydraulic control system of deepwater subsea BOP stacks.Mathematic simulation models of the ram and annular preventers are estab-lished by using SimulationX software.Different cases are studied to verify whether it is appropri-ate to be operated according to API requirements at the water depth of 1 524 m.

  7. Proceedings of the Twenty-First Water Reactor Safety Information Meeting: Volume 1, Plenary session; Advanced reactor research; advanced control system technology; advanced instrumentation and control hardware; human factors research; probabilistic risk assessment topics; thermal hydraulics; thermal hydraulic research for advanced passive LWRs

    Monteleone, S. [Brookhaven National Lab., Upton, NY (United States)] [comp.


    This three-volume report contains 90 papers out of the 102 that were presented at the Twenty-First Water Reactor Safety Information Meeting held at the Bethesda Marriott Hotel, Bethesda, Maryland, during the week of October 25--27, 1993. The papers are printed in the order of their presentation in each session and describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included papers presented by researchers from France, Germany, Japan, Russia, Switzerland, Taiwan, and United Kingdom. The titles of the papers and the names of the authors have been updated and may differ from those that appeared in the final program of the meeting. Individual papers have been cataloged separately. This document, Volume 1 covers the following topics: Advanced Reactor Research; Advanced Instrumentation and Control Hardware; Advanced Control System Technology; Human Factors Research; Probabilistic Risk Assessment Topics; Thermal Hydraulics; and Thermal Hydraulic Research for Advanced Passive Light Water Reactors.

  8. Development of a hydraulic model of the human systemic circulation

    Sharp, M. K.; Dharmalingham, R. K.


    Physical and numeric models of the human circulation are constructed for a number of objectives, including studies and training in physiologic control, interpretation of clinical observations, and testing of prosthetic cardiovascular devices. For many of these purposes it is important to quantitatively validate the dynamic response of the models in terms of the input impedance (Z = oscillatory pressure/oscillatory flow). To address this need, the authors developed an improved physical model. Using a computer study, the authors first identified the configuration of lumped parameter elements in a model of the systemic circulation; the result was a good match with human aortic input impedance with a minimum number of elements. Design, construction, and testing of a hydraulic model analogous to the computer model followed. Numeric results showed that a three element model with two resistors and one compliance produced reasonable matching without undue complication. The subsequent analogous hydraulic model included adjustable resistors incorporating a sliding plate to vary the flow area through a porous material and an adjustable compliance consisting of a variable-volume air chamber. The response of the hydraulic model compared favorably with other circulation models.

  9. Pressure regulation in nonlinear hydraulic networks by positive controls

    De Persis, Claudio; Skovmose Kallesøe, Carsten


    We report on our investigation of an industrial case study of a system distributed over a network, namely a large-scale hydraulic network which underlies a district heating system. The network comprises an arbitrarily large number of end-users and actuators distributed along the network. After intro

  10. High precise control method for a new type of piezoelectric electro-hydraulic servo valve


    A new type of piezoelectric electro-hydraulic servo valve system was proposed. And then multilayer piezoelectric actuator based on new piezoelectric ceramic material was used as the electricity-machine converter of the proposed piezoelectric electro-hydraulic servo valve. The proposed piezoelectric electro-hydraulic servo valve has ascendant performance compared with conventional ones. But the system is of high nonlinearity and uncertainty, it cannot achieve favorable control performance by conventional control method. To develop an efficient way to control piezoelectric electro-hydraulic servo valve system, a high-precise fuzzy control method with hysteresis nonlinear model in feedforward loop was proposed. The control method is separated into two parts: a feedforward loop with Preisach hysteresis nonlinear model and a feedback loop with high-precise fuzzy control. Experimental results show that the hysteresis loop and the maximum output hysteresis by the PID control method are 4.22%and 2.11 μm, respectively; the hysteresis loop and the maximum output hysteresis by the proposed control method respectively are 0.74% and 0.37 μm, respectively; the maximum tracking error by the PID control method for sine wave reference signal is about 5.02%, the maximum tracking error by the proposed control method for sine wave reference signal is about 0.85%.

  11. A conceptual model of check dam hydraulics for gully control

    C. Castillo


    Full Text Available There is little information in scientific literature regarding the modifications induced by check dam systems in flow regimes in restored gully reaches, despite it being a crucial issue for the design of conservation measures. Here, we develop a conceptual model to classify flow regimes in straight rectangular channels for initial and dam-filling conditions as well as a method of estimating efficiency in order to provide guidelines for optimal design. The model integrates several previous mathematical approaches for assessing the main processes involved (hydraulic jump HJ, impact flow, gradually varied flows. Its performance was compared with the simulations obtained from IBER, a bi-dimensional hydrodynamic model. The impact of check dam spacing (defined by the geometric factor of influence c on efficiency was explored. Eleven main classifications of flow regimes were identified depending on the element and level of influence. The model produced similar results when compared with IBER, but led to higher estimations of HJ and impact lengths. Total influence guaranteed maximum efficiency and HJ control defining the location of the optimal c. Geometric total influence (c = 1 was a valid criterion for the different stages of the structures in a wide range of situations provided that hydraulic roughness conditions remained high within the gully, e.g. through revegetation. Our total influence criterion involved shorter spacing than that habitually recommended in technical manuals for restoration, but was in line with those values found in spontaneous and stable step-pools systems, which might serve as a reference for man-made interventions.

  12. Dynamic extending nonlinear H∞ control and its application to hydraulic turbine governor


    There exists a large class of nonlinear systems with uncertainties, such as hydraulic turbine governors, whose robust control problem is hard to solve by means of the existing robust control approaches. For this class of systems, this work presents a dynamic extending H∞ controller via both differential geometry and H∞ theory. Furthermore, based on differential game theory, it has been verified that the proposed control strategy has robustness in the sense that the disturbance can be attenuated effectively because the L2-gain from the disturbance input to the regulation output signal could be reduced to any given level. Thirdly, a robust control strategy for hydraulic turbine governor is designed according to the proposed extending H∞ control method, and has been developed into a real control equipment. Finally the field experiments are carried out which show clearly that the developed control equipment can enhance transient stability of power systems more effectively than the conventional controller.

  13. A Review on Mechanical and Hydraulic System Modeling of Excavator Manipulator System

    Jiaqi Xu


    Full Text Available A recent trend in the development of off-highway construction equipment, such as excavators, is to use a system model for model-based system design in a virtual environment. Also, control system design for advanced excavation systems, such as automatic excavators and hybrid excavators, requires system models in order to design and simulate the control systems. Therefore, modeling of an excavator is an important first step toward the development of advanced excavators. This paper reviews results of recent studies on the modeling of mechanical and hydraulic subsystems for the simulation, design, and control development of excavator systems. Kinematic and dynamic modeling efforts are reviewed first. Then, various approaches in the hydraulic system modeling are presented.

  14. Hydraulically actuated hexapod robots design, implementation and control

    Nonami, Kenzo; Irawan, Addie; Daud, Mohd Razali


    Legged robots are a promising locomotion system, capable of performing tasks that conventional vehicles cannot. Even more exciting is the fact that this is a rapidly developing field of study for researchers from a variety of disciplines. However, only a few books have been published on the subject of multi-legged robots. The main objective of this book is to describe some of the major control issues concerning walking robots that the authors have faced over the past 10 years. A second objective is to focus especially on very large hydraulically driven hexapod robot locomotion weighing more than 2,000 kg, making this the first specialized book on this topic. The 10 chapters of the book touch on diverse relevant topics such as design aspects, implementation issues, modeling for control, navigation and control, force and impedance control-based walking, fully autonomous walking, walking and working tasks of hexapod robots, and the future of walking robots. The construction machines of the future will very likel...

  15. Pressure Control Characteristics of Main Transmission System of Hydraulic Transmission Wind Energy Conversion System%液压型风力发电机组主传动系统压力控制特性研究

    艾超; 叶壮壮; 孔祥东; 廖利辉


    Fixed displacement pump-variable displacement motor is the main drive system of hy-draulic type wind turbine,the system is controlled by a variable displacement mechanism after grid-connected.To study the pressure control characteristics,a mathematical model was built and the trans-fer function describing the pressure to the position of the motor swash plate was derived.Compared with the identified model obtained from data identification in MATLAB system,the built model was verified,which laid theoretical and test foundation for further maximum power point tracking(MPPT) based on pressure control in hydraulic type wind turbine.%液压型风力发电机组主传动系统为定量泵变量马达闭式系统,风机并网后依靠变量马达变排量机构对系统进行控制。研究了系统压力控制特性,建立了并网后主传动系统数学模型,得出了系统压力对马达斜盘摆角的传递函数。利用 MATLAB 辨识工具箱,根据实验数据,对系统压力控制模型进行数据辨识,并与理论模型进行对比,验证了理论模型的准确性,为液压型风力发电机组通过压力控制实现最佳功率追踪控制奠定理论与实验基础。

  16. Development and industrial tests of the first LNG hydraulic turbine system in China

    Jie Chen


    Full Text Available The cryogenic hydraulic turbine can be used to replace the conventional J–T valve for LNG or mixed refrigerant throttling and depressurization in a natural gas liquefaction plant. This advanced technology is not only to enhance the efficiency of the liquefaction plant, but to usher a new trend in the development of global liquefaction technologies. China has over 136 liquefaction plants, but the cryogenic hydraulic turbines have not been deployed in industrial utilization. In addition, these turbines cannot be manufactured domestically. In this circumstance, through working on the key technologies for LNG hydraulic turbine process & control system development, hydraulic model optimization design, structure design and manufacturing, the first domestic cryogenic hydraulic turbine with a flow rate of 40 m3/h was developed to recover the pressure energy from the LNG of cold box. The turbine was installed in the CNOOC Zhuhai Natural Gas Liquefaction Plant for industrial tests under multiple working conditions, including start-stop, variable flow rates and variable rotation speeds. Test results show that the domestic LNG cryogenic hydraulic turbine has satisfactory mechanical and operational performances at low temperatures as specified in design. In addition, the process & control system and frequency-conversion power-generation system of the turbine system are designed properly to automatically and smoothly replace the existing LNG J–T valve. As a result, the domestic LNG cryogenic hydraulic turbine system can improve LNG production by an average of 2% and generate power of 8.3 kW.

  17. Pressure Control for a Hydraulic Cylinder Based on a Self-Tuning PID Controller Optimized by a Hybrid Optimization Algorithm

    Ru Wang


    Full Text Available In order to improve the performance of the hydraulic support electro-hydraulic control system test platform, a self-tuning proportion integration differentiation (PID controller is proposed to imitate the actual pressure of the hydraulic support. To avoid the premature convergence and to improve the convergence velocity for tuning PID parameters, the PID controller is optimized with a hybrid optimization algorithm integrated with the particle swarm algorithm (PSO and genetic algorithm (GA. A selection probability and an adaptive cross probability are introduced into the PSO to enhance the diversity of particles. The proportional overflow valve is installed to control the pressure of the pillar cylinder. The data of the control voltage of the proportional relief valve amplifier and pillar pressure are collected to acquire the system transfer function. Several simulations with different methods are performed on the hydraulic cylinder pressure system. The results demonstrate that the hybrid algorithm for a PID controller has comparatively better global search ability and faster convergence velocity on the pressure control of the hydraulic cylinder. Finally, an experiment is conducted to verify the validity of the proposed method.

  18. 1st International Conference on Hydraulic Design in Water Resources Engineering : Channels and Channel Control Structures


    The development of water resources has proceeded at an amazing speed around the world in the last few decades. The hydraulic engineer has played his part: in constructing much larger artificial channels than ever before, larger and more sophisticated control structures, and systems of irrigation, drainage and water supply channels in which the flow by its nature is complex and unsteady requiring computer-based techniques at both the design and operation stage. It seemed appropriate to look briefly at some of the developments in hydraulic design resulting from this situation. Hence the idea of the Conference was formed. The Proceedings of the Conference show that hydraulic engineers have been able to acquire a very substantial base of design capability from the experience of the period referred to. The most outstanding development to have occurred is in the combination of physical and mathematical modelling, which in hydraulic engineering has followed a parallel path to that in other branches of engineering sc...

  19. Servo Controlled Variable Pressure Modification to Space Shuttle Hydraulic Pump

    Kouns, H. H.


    Engineering drawings show modifications made to the constant pressure control of the model AP27V-7 hydraulic pump to an electrically controlled variable pressure setting compensator. A hanger position indicator was included for continuously monitoring hanger angle. A simplex servo driver was furnished for controlling the pressure setting servovalve. Calibration of the rotary variable displacement transducer is described as well as pump performance and response characteristics.

  20. 新型液压并联遥操纵手力反馈伺服控制研究%Research on a Novel Parallel Hydraulic Haptic Master Servo Control System

    冯石柱; 徐鸣; 赵丁选; 苏波


    以一种新型六自由度液压并联力反馈遥操纵手为研究对象,以其输出力为控制目标,建立力控制系统数学模型,设计广义预测控制( GPC)系统实现六自由度遥操纵主手的控制.并搭建遥操纵实验台对其操作性能进行验证,实验结果表明,所设计的控制系统克服了系统参数不确定性、建模误差等不利因素的影响,获得了良好的动、静态响应特性.文中工作对液压伺服操纵手的控制研究有一定参考价值.%Using a parallel hydraulic Stewart-6-DOF platform as a force reflecting haptic master,the force based model is deduced and the general predictive control ( GPC ) theory is used for the design of the controller to control the 6-DOF parallel hydraulic force reflecting haptic master. The servo control system test bench has been set up by using a piece of the 6-DOF master. The test results show that the control system overcomes the model error and uncertainty and gain better both dynamic and static respondence. It is of certain significance for parallel hydraulic haptic master control system design.

  1. Modeling and simulation of electronic control full hydraulic steering system for grain combine harvester%谷物联合收割机电控全液压转向系统建模与仿真

    张成涛; 谭彧; 吴刚; 王书茂


    In recent years, combine harvester navigation system based on machine vision had important significance in improving the harvesting efficiency of combine harvester, reducing the labor intensity of the driver and so on. In order to realize the automatic steering control of the combine operation path, it is necessary to reconstruct the original hydraulic steering system of combine harvester. To analyze the steering performance of the modified electronically controlled hydraulic steering system for combine harvester in visual navigation system, mathematical models of the electronically controlled hydraulic steering system were established after introducing the structure of combine harvester visual navigation system. The system was mainly composed of combine harvester body, full hydraulic steering, steering transmission mechanism and hybrid stepping motor. In this paper, the mathematical models of the parts were established respectively. The steering model of combine harvester was firstly simplified to linear 2-DOF rear wheel steering vehicle model, and the basic handling dynamics model of combine harvester was established. Then, the dynamic mathematical model of simplified hydraulic steering system was given in the analysis of the fully hydraulic steering work principle for combine harvester. And then, the static model of the steering transmission mechanism was established according to its geometrical structures. Finally, the stepping motor model was simplified as an inertial system according to the step response performance, and its transfer function was given. The electronically controlled hydraulic steering system was simulated through the joint simulation method of each mathematical model by Simulink software. In order to verify the correctness of simulation models, the dynamic response characteristics of steering system was tested with the steering wheel angle step input of 90° on Xinjiang 2A combine harvester. In the real vehicle test, vehicle yaw rate was

  2. Development of A Hydraulic Drive for a novel Diesel-Hydraulic system for Large commercial Vehicles

    Stecki, J. S.; Conrad, Finn; Matheson, P.;


    The objectives and results of the research project Hybrid Diesel-Hydraulic System for Large commercial vehicles, e.g. urban freight delivery, buses or garbage trucks. The paper presents and discusses the research and development of the system, modelling approach and results from preliminary...

  3. Reliability modeling of hydraulic system of drum shearer machine

    SEYED HADI Hoseinie; MOHAMMAD Ataie; REZA Khalookakaei; UDAY Kumar


    The hydraulic system plays an important role in supplying power and its transition to other working parts of a coal shearer machine.In this paper,the reliability of the hydraulic system of a drum shearer was analyzed.A case study was done in the Tabas Coal Mine in Iran for failure data collection.The results of the statistical analysis show that the time between failures (TBF)data of this system followed the 3-parameters Weibull distribution.There is about a 54% chance that the hydraulic system of the drum shearer will not fail for the first 50 h of operation.The developed model shows that the reliability of the hydraulic system reduces to a zero value after approximately 1 650 hours of operation.The failure rate of this system decreases when time increases.Therefore,corrective maintenance(run-to-failure)was selected as the best maintenance strategy for it.

  4. Turbogas control unit using a hydraulic interface; Control de una unidad turbogas usando una interfase hidraulica

    Ramirez Palacios, Ignacio Ramon; Castelo Cuevas, Luis [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail:;; Escarcega Navarrete, Luis [Servi-Control Monterrey S.A. de C.V., Monterrey, Nuevo Leon (Mexico)]. E-mail:


    This paper presents the design and implementation of the control system of the Turbo Generator Unit (TGU) GE 5001, placed in Laguna Chavez power generation facility in Gomez Palacio, Dgo., Mexico. This TGU had been operating with an old control system, back to the 70's. The positioning of the control valves was carried out using a complex electro-hydraulic system. For the modernization of the control system, we use latest PLC technology and a current to pressure converter to communicate the PLC with the hydraulic control valves. The new control system helped us to obtain a best response at the start and generation phases, as well as an increase in the availability of the unit. We show the old and the new control architectures besides plot results obtained at the different operation points. [Spanish] En este articulo se presenta la implementacion y diseno del sistema de control de una Unidad Turbogas (UTG) GE-5001 de la Central Turbogas Laguna Chavez de CFE ubicada en Gomez Palacio, Durango, la cual originalmente era controlada mediante un sistema de control con tecnologia de los anos 70's. El posicionamiento de las valvulas de control se realizaba mediante un sistema electro-hidraulico complejo. Para la modernizacion del sistema de control a uno con tecnologia de punta fue necesario utilizar una interfase hidraulica por medio de un convertidor de corriente/presion (I/P) para el posicionamiento de las valvulas originales. Con la modernizacion se mejoro la respuesta del control asi como el incremento de la disponibilidad de la unidad. Se presentan la arquitectura anterior y actual de sistema de control asi como graficas de los resultados obtenidos en diferentes puntos de operacion de la UTG.

  5. Robust Control of Industrial Hydraulic Cylinder Drives - with Special Reference to Sliding Mode- & Finite-Time Control

    Schmidt, Lasse

    are widely used. Such controllers typically provide the possibility to employ traditional linear controls such as PID schemes, and variants of this, with parameters tunable via graphical user interfaces. However, due to the intrinsic nonlinearities of hydraulic systems as well as the often limited knowledge...... extensions / modifications of first- and second order sliding controls show to be especially suitable for hydraulic cylinder drives operating under industrial conditions. These controllers demonstrate superior performance compared with conventional methods, and may be commissioned with limited tuning effort...

  6. Stability of Hydraulic Systems with Focus on Cavitating Pumps

    Brennen, C. E.; Braisted, D. M.


    Increasing use is being made of transmission matrices to characterize unsteady flows in hydraulic system components and to analyze the stability of such systems. This paper presents some general characteristics which should be examined in any experimentally measured transmission matrices and a methodology for the analysis of the stability of transmission matrices in hydraulic systems of order 2. These characteristics are then examined for cavitating pumps and the predicted instabilities (kn...

  7. Technology of load-sensitivity used in the hydraulic system of an all-hydraulic core rig

    XIN De-zhong; CHEN Song-ling; WANG Qing-feng


    The existing hydraulic system always have problems of temperature rise, run-ning stability and anti-interference of the implementation components, reliability of hydrau-lic components, maintenance difficulties, and other issues. With high efficiency, energy saving, reliability, easy operating, stable running, anti-interference ability, and other ad-vantages, the load-sensitive hydraulic system is more suitable for coal mine all-hydraulic core rig. Therefore, for the technical development of the coal mine all-hydraulic core rig, the load-sensitive technology employed by the rig should be of great significance.

  8. Research on hydraulic slotting technology controlling coal-gas outbursts

    WEI Guo-ying; SHAN Zhi-yong; ZHANG Zi-min


    Measured to control serious coal-gas outburst in coal seam were analyzed by theory and experimented in test site. A new technique to distress the coal-bed and drain methane, called hydraulic slotting, was described in detail, and the mechanism of hydrau-lic slotting was put forward and analyzed. The characteristic parameter of hydraulic slotting was given in Jiaozuo mining area and the characteristic of validity, adaptability and secu-rity was evaluated. The results show that the stress surrounding the strata and the gas in coal seam is released efficiently and thoroughly while new techniques are taken, as slot-ting at heading face by high pressure large diameter jet. The resistance to coal and gas outbursts is increased dramatically once the area of slotting is increased to a certain size.In the process of driving 2 000 m tunnel by hydraulic slotting excavation, coal and gas outburst never occurre. The technique could be used to prevent and control potential coal-gas outburst in the proceeding of tunnel driving, and the speed tunneling could be as high as more than 2 times.

  9. Representing plant hydraulics in a global Earth system model.

    Kennedy, D.; Gentine, P.


    Earth system models need improvement to reproduce observed seasonal and diurnal cycles of photosynthesis and respiration. Model water stress parameterizations lag behind the plant physiology literature. A plant hydraulics model is developed and deployed in a global Earth system model (NCAR CESM 1.2.2 with CLM 4.5). Assimilation and transpiration are attenuated according to literature cavitation curves. Water stress is evaluated based on plant functional type hydraulic parameters forced by soil moisture and atmospheric conditions. Resolving the plant water status allows for modelling divergent strategies for water stress. The case of isohydric versus anisohydric species is presented, showing that including plant hydraulic traits alter modelled photosynthesis and transpiration.

  10. Hydraulic Control Design and Modeling Techniques.


    methodologies. This report may be difficult to read for the casual reader . It is written assuming the reader has some fundamental background in control...INTERVAL DTSMP=.O0012207 STEP=. 0012207 INDEX=INDEX+i DOUT( INDEX2)=L1 A- 4 END $*OF DISCRETE SAMP 2" DERIVATIVE tarot (INDEX2 .GE. 4098) END $*OF

  11. 水下采油树地面测试单元液压控制系统设计与仿真%Design and Simulation of the Ground Test Unit Hydraulic Control System for Subsea Tree

    欧宇钧; 袁晓兵; 卢沛伟; 罗玉贵; 杨文; 苏瑞华; 张云卫; 张长齐; 蔡宝平


    The test of subsea tree can provide a reference for its maintenance. A ground test unit hydraulic control system for subsea trees was designed according to the principal parameters of subsea tree control system and subsea tree test procedures. It contained fluid reservoir, high pressure pump circuit, water pump circuit, accumulators, pressure regulating circuit, interface circuit and return cir⁃cuit. Then the main parameters of the hydraulic system key components were calculated, based on the principal parameters of subsea tree control system and subsea tree test requirements. AMESim was used for modeling and simulation of the ground test unit hydraulic control system. Through the analysis of simulation results, it is proved that the test unit can provide stable hydraulic fluid and it has a good con⁃trol effect.%对水下采油树进行测试验证可为水下采油树的维修保养提供参考。通过对水下采油树控制系统主参数以及水下采油树测试流程的研究,设计一套水下采油树地面测试单元液压控制系统,水下采油树地面测试单元液压控制系统包括油箱、高压泵回路、水泵回路、蓄能器组、调压回路、接口回路、回油回路等。根据系统主参数及测试要求,对液压控制系统主要元件进行主参数的计算。利用AMESim软件建立水下采油树地面测试单元液压控制系统模型,对模型进行仿真分析。结果表明,所设计的液压控制系统具有良好的控制性和稳定性。


    Dong Longlei; Yan Guirong; Li Ronglin


    The mechanical characteristics of the electro-hydraulic servo system in the centrifuge field are analyzed.The hydraulic pressure law in the centrifuge field indicates the existence of the centrifuge hydraulic pressure.The mechanical characteristics of the slide-valve and the dual nozzle flapper valve are studied,and it is found that the centrifuge field can not only increase the driving force or moment of the function units,but also decrease the stability of the components.Finally by applying Gauss minimum constraint principle,the dynamic model of the electro-hydraulic vibrator in the centrifuge field is established,and the mechanical restriction of the system is also presented.The study will be helpful for the realization of the combined vibration and centrifuge test system.

  13. 总线型伺服阀在装车站液压及控制系统中的应用%Application of Bus-type Servo Valve in Hydraulic and Control System of Loading Station

    姚志星; 张康


    In view of problems of frequent faults and low integration degree existed in traditional hydraulic and control system of loading station , the paper proposed a design scheme of hydraulic and control system of loading station based on bus-type servo valve. It gave hardware structure of the system and introduced software design in details, namely parameters setting of servo valve, configuration of industrial gateway and integration between industrial gateway and PLC. The actual application showed that the system runs stably and reliably, which meets requirements ol coal transportation.%针对传统的装车站液压及控制系统存在故障多、集成化程度低的问题,提出了一种基于总线型伺服阀的装车站液压及控制系统的设计方案;给出了该系统的硬件结构,详细介绍了该系统的软件设计,即伺服阀参数设置、工业网关配置及工业网关与PLC系统的集成.实际应用表明,该系统运行稳定、可靠,满足了煤炭运输的需求.

  14. Design of a Disk Brake for Belt Conveyor Hydraulic Control System Design%一种带式输送机盘式制动器液压控制系统的设计



      文中基于盘式制动器设计了一个液压控制系统,该系统的设计是针对带式运输机在运输过程中的控制问题设计的,所以它的稳定性能和反映能力都占有绝对的优势。文中简单的介绍了液压系统遇到松闸过程、保压过程、正常停车、超速制动、紧急制动和系统突然断电等情况时的运行状况。%  Based on the design of disk brake on a hydraulic control system, the system design is for the belt conveyor in the transportation process control design, so its stability properties and screening ability has the absolute advantage. This paper introduces the hydraulic system of brake loosing process, encountered pressure, normal parking, overspeed braking, emergency braking and system failure, when the running state airport.

  15. Analysis on the Pressure Fluctuation Law of a Hydraulic Exciting System with a Wave-exciter

    WEI Xiu-ye; KOU Zi-ming; LU Zi-rong


    A hydraulic exciting system with a wave exciter has been constructed in order to study the hydraulic vibra- tion law. The system consists of an oil source, wave-exciter and oil cylinder, and is controlled by a wave-exciter. The working principle of the hydraulic exciting system and wave exciter has been analyzed, and its excitation process has been illustrated. The law of every pipe's pressure fluctuation of the system is obtained by experiment. The theo- retical analysis and experimental data prove that the pipeline pressure periodically changes and the pipeline pressure fluctuation frequency is independently controlled by the excitation frequency of the wave-exciter. Every pipelinc's pressure wave is produced by system flow fluctuation and water hammer coupling. The pressure fluctuation rules of the system provide a theoretical basis for the study of the associated liberation system.

  16. Optimisation of Working Areas in Discrete Hydraulic Power Take off-system for Wave Energy Converters

    Hansen, Anders Hedegaard; Hansen, Rico Hjerm; Pedersen, Henrik C.


    Fluid power is the leading technology in Power Take Off(PTO) systems in Wave Energy Converters(WEC’s), due to the capability of generating high force at low velocity. However, as hydraulic force controlling system may suffer from large energy losses the efficiency of the hydraulic PTO systems may...... be a limiting factor for wave energy. Therefore, a secondary controlled force system has been proposed as PTO element for WEC’s. This paper investigates the configuration of a multi-chamber cylinder utilising two common pressure lines. By usage of model based optimisation an optimal number and size of working...

  17. State of the art-hydraulic yaw systems for wind turbines

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole;


    This paper addresses the yawing systems of Horizontal Axis Wind Turbines (HAWT’s). HAWT’s represents close to all of the commercial large wind turbines sold today and must be considered state-of-the art within wind turbine technology. Two choices exists when considering components for the active...... mounted with a reduction gear. This paper presents state-of-the art within; hydraulic yaw system design and control of yaw systems in general. Primary focus on the advantages and disadvantages of using a hydraulic system for controlling the yaw of a wind turbine with a soft yaw concept....

  18. An Analytic Approach to Cascade Control Design for Hydraulic Valve-Cylinder Drives

    Schmidt, Lasse; Hansen, Anders Hedegaard; Andersen, Torben O.;


    considering cylinder drives. A widely used approach with electrical drives is state controller cascade control, that may by successfully applied to manipulate the drive dynamics in order to achieve high bandwidths etc., due to the nearly constant parameter-nature of such drives. Such properties are however...... relation, ideally eliminating the system gain variation, and the linear model equations for the pre-compensated system is used for the cascade control design. The cascade design does not utilize e.g. bode plots, root loci etc., and is based on an analytic approach, emphasizing the exact influence of each......Motion control design for hydraulic drives remains to be a complicated task, and has not evolved on a level with electrical drives. When considering specifically motion control of hydraulic drives, the industry still prefers conventional linear control structures, often combined with feed forward...

  19. 被动式钻柱升沉补偿装置气液控制系统的原理%Principle of Air-Hydraulic Control System of Passive Drill Pipe Heave Compensation Equipment

    王维旭; 于兴军; 贾秉彦; 张鹏


    The paper mainly presents the theme on passive drill pipe heave compensation equipment through the following aspects: system constitution, working principle, manipulation, control principle of air-hydraulic control system, etc.With the air-hydraulic control technology, the passive drill pipe heave compensation equipment has many functions,such as regulate of working pressure, hydroacoustic padlock, mechanical padlock, closedown of accumulator, and so on.The equipment can eliminate the molestation which the wave impact on the vertical position of drill pipe when the drilling work is doing on the floating platform.The drill pipe heave compensation equipment can maintain the normal production of floating platform.%重点介绍了一种被动式钻柱升沉补偿装置的组成、工作原理、操作、气液控制系统原理等.该装置采用气-液控制技术,可实现系统工作压力调节、液压锁紧、机械锁紧、储能器关闭等功能,利用该装置可有效地解决浮式钻井平台作业过程中波浪对钻井设备竖直方向的位置扰动问题,保障了正常的生产.

  20. Design of the Electro-hydraulic Proportional Control System of Coconut Picking Machine%椰果采摘机的电液比例控制系统设计



    In view of the defaults of general pressure valve controlled coconut picking machine, such as complex operation, less flexible, fuzz-y positioning and high damage rate of coconuts, a new picking machine with the electro-hydraulic proportional control system was designed. In order to reduce the production costs and facilitate operation, the machine was open-loop controlled with digital computer program and electro-hydraulic proportional control valve, it could successfully complete all kinds of coconut picking operations in a stable and precise way.%针对采用普通压力阀多级压力控制系统的椰果采摘机的操作复杂、自由度低、定位模糊和椰果损伤率较高等缺点,设计了一种采用电液比例控制系统的椰果采摘机.同时为了降低生产成本、便于操作,采用了计算机数字程序与电液比例调速阀进行开环控制.该机能够准确可靠地完成椰果采摘作业的各种动作,其动作稳定性好,定位准确,可达到较理想的操作效果.

  1. Improvement of Control and Hydraulic System for Turnover Body in Strips Case Filling and Tipping Machine%片烟装箱翻包机翻转体控制及液压系统的改进

    王德吉; 王志国; 谢建; 刘俊峰


    为解决片烟装箱翻包机在翻包过程中,翻转体出现抖动,且液压油温及驱动电机机壳温度偏高等问题,采用基于先验知识的LS-SVM(Least Squares Support Vector Machines)理论,对皮带输送机定位方式进行了优化.利用PLC编程对翻转体控制系统进行改进,采用轴流风机和压缩机制冷技术对电机和液压油分别进行冷却处理,重新调整液压系统的工作压力.结果表明:改进后消除了液压缸向外渗油和翻转体抖动现象,翻转体对油缸活塞杆支撑区域出现的开裂现象由3~4次/年减少为0,电机机壳温度由65 ℃降至44 ℃,液压油温由55 ℃降至37 ℃左右,有效降低了设备故障率,提高了设备运行的可靠性和安全性.%As a solution to the dithering of turnover body and high temperatures of hydraulic oil and driving motor, the positioning means of belt conveyor was optimized by a prior knowledge based LS-SVM (Least Square Support Vector Machine) theory. The control system for turnover body was improved by PLC programming; motor and hydraulic oil were cooled by axial flow fan and compressor refrigeration technology respectively; and the working pressure of hydraulic system was readjusted. The results showed that after improvement, the leakage of hydraulic oil and the dithering of turnover body were eliminated, the cracking in the supporting area of turnover body to the piston rod of oil cylinder decreased from 3-4 times/year to 0, the temperature of motor lowered from 65 to 44 ℃ and that of hydraulic oil lowered from 55 to 37 ℃. The failure rate of equipment was effectively reduced, while the reliability and safety of equipment running were promoted.

  2. Contaminant monitoring of hydraulic systems. The need for reliable data

    Day, M.J. [Pall Europe Ltd., Portsmouth (United Kingdom)] Rinkinen, J. [Tampere University of Technology, Tampere (Finland)


    The need for both reliable operation of hydraulic and lubrication systems and long component lives has focused users to the benefits of controlling the contamination in the hydraulic fluid. Maximum operating (target) levels are being implemented as part of a condition based maintenance regime. If these are exceeded, maintenance effort is directed to correcting the rise in consummation level, and so make optimum use of resources as maintenance effort is only affected when it is necessary to do so. Fundamental to ibis aspect of condition based monitoring is the provision of accurate and reliable data in the shortest possible time. This way, corrective actions can be implemented immediately so minimising the damage to components. On-line monitoring devices are a way of achieving this and are seeing increased use, but some are affected by the condition of the fluid. Hence, there is a potential for giving incorrect data which will waste time and effort by initiating unnecessary corrective actions. A more disturbing aspect is the effect on the user of continual errors. The most likely effect would be a loss of confidence in the technique or even complete rejection of it and hence the potential benefits will be lost. This presentation explains how contaminant monitoring techniques are applied to ensure that the potential benefits of operating with clean fluids is realised. It examines the sources of error and shows how the user can interrogate the data and satisfy himself of its authenticity. (orig.) 14 refs.

  3. Modeling and control of a hydraulically actuated flexible-prismatic link robot

    Love, L.; Kress, R.; Jansen, J.


    Most of the research related to flexible link manipulators to date has focused on single link, fixed length, single plane of vibration test beds. In addition, actuation has been predominantly based upon electromagnetic motors. Ironically, these elements are rarely found in the existing industrial long reach systems. This manuscript describes a new hydraulically actuated, long reach manipulator with a flexible prismatic link at Oak Ridge National Laboratory (ORNL). Focus is directed towards both modeling and control of hydraulic actuators as well as flexible links that have variable natural frequencies.

  4. Development of realistic thermal-hydraulic system analysis codes ; development of thermal hydraulic test requirements for multidimensional flow modeling

    Suh, Kune Yull; Yoon, Sang Hyuk; Noh, Sang Woo; Lee, Il Suk [Seoul National University, Seoul (Korea)


    This study is concerned with developing a multidimensional flow model required for the system analysis code MARS to more mechanistically simulate a variety of thermal hydraulic phenomena in the nuclear stem supply system. The capability of the MARS code as a thermal hydraulic analysis tool for optimized system design can be expanded by improving the current calculational methods and adding new models. In this study the relevant literature was surveyed on the multidimensional flow models that may potentially be applied to the multidimensional analysis code. Research items were critically reviewed and suggested to better predict the multidimensional thermal hydraulic behavior and to identify test requirements. A small-scale preliminary test was performed in the downcomer formed by two vertical plates to analyze multidimensional flow pattern in a simple geometry. The experimental result may be applied to the code for analysis of the fluid impingement to the reactor downcomer wall. Also, data were collected to find out the controlling parameters for the one-dimensional and multidimensional flow behavior. 22 refs., 40 figs., 7 tabs. (Author)

  5. 矿用牵引机车电液控制系统的设计与研究%Design and study of electro-hydraulic control system for mine-used traction locomotives

    徐莉萍; 郑永光; 任德志


    According to the requirements of the traction locomotive proposed by long-tunneled construction, a kind of electro-hydraulic control system for mine-used traction locomotives is designed. The control system adopts PID intelligent control algorithm to adjust the displacement of variable pump and variable motor intelligently, so as to make the output rotary speed to reach the given one. In addition, the model of the electro hydraulic control system is built with simulation software AMEsim, and relevant parameters are optimized and dynamic control simulation is accomplished. The simulation and experiment results show that the system accurately, quickly and stably adjusts the rotary speed.%针对长大隧道施工对牵引机车的要求,设计了牵引机车电控液驱控制系统.该控制系统采用PID智能控制算法分别对变量泵和变量马达的排量进行智能调节,使输出转速达到设定转速.运用AMEsim液压仿真软件平台对牵引机车电液控制系统进行建模,并对相关参数进行优化设计,实现动态控制仿真.对控制系统进行了仿真和试验,结果表明,其能够准确、快速、平稳地对转速进行调节.

  6. Optimal Control of Nonlinear Hydraulic Networks in the Presence of Disturbance

    Tahavori, Maryamsadat; Leth, John-Josef; Kallesøe, Carsten;


    Water leakage is an important component of water loss. Many methods have emerged from urban water supply systems for leakage control, but it still remains a challenge in many countries. Pressure management is an effective way to reduce the leakage in a system. It can also reduce the power consump...... control problem is the interior point method. The method which is used in this paper can be used for a general hydraulic networks to optimize the leakage and energy consumption and to satisfy the demands at the end-users....... consumption. To this end, an optimal control strategy is proposed in this paper. In the water supply system model, the hydraulic resistance of the valve is estimated by the real data from a water supply system and it is considered to be a disturbance. The method which is used to solve the nonlinear optimal...


    Yao Chengyu; Zhao Jingyi


    To overcome the design limitations of traditional hydraulic control system for synthetic rubber press and such faults as high fault rate, low reliability, high energy-consuming and which always led to shutting down of post-treatment product line for synthetic rubber, brand-new hydraulic system combining with PC control and two-way cartridge valves for the press is developed, whose reliability is analyzed, reliability model of the hydraulic system for the press is established by analyzing processing steps, and reliability simulation of each step and the whole system is carried out by software MATLAB, which is verified through reliability test. The fixed time test has proved not that theory analysis is sound, but the system has characteristics of reasonable design and high reliability,and can lower the required power supply and operational energy cost.

  8. Hydraulic Soft Yaw System Load Reduction and Prototype Results

    Stubkier, Søren; Pedersen, Henrik C.; Markussen, Kristian


    Introducing a hydraulic soft yaw concept for wind turbines leads to significant load reductions in the wind turbine structure. The soft yaw system operates as a shock absorption system on a car, hence absorbing the loading from turbulent wind conditions instead of leading them into the stiff wind...... operates. Further it is analyzed how the soft yaw system influence the power production of the turbine. It is shown that the influence is minimal, but at larger yaw errors the effect is possitive. Due to the implemeted functions in the hydraulic soft yaw system such as even load distribution on the pinions...

  9. Hydraulic External Pre-Isolator System for LIGO

    Wen, S; Mason, K; Giaime, J; Abbott, R; Kern, J; O'Reilly, B; Bork, R; Hammond, M; Hardham, C; Lantz, B; Hua, W; Coyne, D; Traylor, G; Overmier, H; Evans, T; Hanson, J; Spjeld, O; Macinnis, M; Mailand, K; Sellers, D; Carter, K; Sarin, P


    The Hydraulic External Pre-Isolator (HEPI) is the first 6 degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGO's 5th science run, successfully cutting down the disturbance seen by LLO's suspended optics in the two most prominent seismic disturbance bands, the microseism (0.1-0.3Hz) and the anthropogenic (1-3Hz) bands, by a factor of a few to tens. The improvement in seismic isolation contributed directly to LLO's much improved duty cycle of 66.7% and LIGO's triple coincident duty cycle of 53%. We report the design, control scheme, and isolation performance of HEPI at LLO in this paper. Aided with this success, funding for incorporating HEPI into the LIGO Hanford Observatory was approved and installation is currently underway.

  10. Hydraulic external pre-isolator system for LIGO

    Wen, S.; Mittleman, R.; Mason, K.; Giaime, J.; Abbott, R.; Kern, J.; O'Reilly, B.; Bork, R.; Hammond, M.; Hardham, C.; Lantz, B.; Hua, W.; Coyne, D.; Traylor, G.; Overmier, H.; Evans, T.; Hanson, J.; Spjeld, O.; Macinnis, M.; Mailand, K.; Ottaway, D.; Sellers, D.; Carter, K.; Sarin, P.


    The hydraulic external pre-isolator (HEPI) is the first six degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGO's fifth science run7, successfully cutting down the disturbance seen by LLO's suspended optics in the two most prominent seismic disturbance bands, the microseism (0.1-0.3 Hz) and the anthropogenic (1-3 Hz) bands, by a factor of a few to tens. The improvement in seismic isolation contributed directly to LLO's much improved duty cycle of 66.7% and LIGO's triple coincident duty cycle of 53%. We report the design, control scheme, and isolation performance of HEPI at LLO in this paper. Aided by this success, funding for incorporating HEPI into the LIGO Hanford Observatory was approved and installation is currently underway.

  11. Oil Film Compensation Control of Hydraulic AGC System in Tandem Cold Rolling Mill%冷连轧机液压AGC系统油膜补偿控制

    孙孟辉; 王益群


    Since the request to the quality of cold rolling sheet strips is higher, the hydraulic AGC ( Automatic Gauge Control) has become the indispensable means which improves the product precision of cold rolling strips. However, to the tandem cold rolling mill which backup roll adopts the oil film bearing, the thickness of oil film changes with different rolling force and rolling velocity, which influences the exit thickness of strips and brings the thickness deviation. Especially for the tandem cold rolling mill, the accumulative deviation of every stand enlarges more the deviation of steel product. The oil film compensation model, which adapted to the practical control, was regressed from the data measured from production locale, aiming at one 5-stand tandem cold rolling mill as object. The control strategy was brought forward, which adapted to the distributed computer control. All of them were applied in the practical rolling process for compensation of changes in thickness of oil film. The experimental result indicates that length of out-toler-ance and value of out-tolerance between head and tail of steel product are reduced notably.%由于对冷轧薄板质量要求的提高,液压AGC已经成为提高冷轧带钢成品精度必不可少的手段.然而对于支撑辊采用油膜轴承的冷连轧机来说,其轴承油膜厚度随着轧制力和轧制速度的变化而变化,这将影响轧件的轧出厚度,造成厚差.尤其对冷连轧机,各机架的累积误差会使成品带的超差更加严重.以某五机架冷连轧机为研究对象,由生产现场实测数据回归出适合于实际控制的油膜补偿模型,提出适合于分布式计算机控制的控制策略,并将其应用于实际轧制过程中对油膜厚度变化进行补偿.实验结果表明:加入油膜补偿控制后,成品带钢厚差带头带尾超差段有较为显著的减少,且超差值也有所降低.

  12. Research on Servo Performance of Heavy Duty Truck Clutch Operating System with Hydraulic Control and Gas Power-assistance%重型货车离合器液压气助力操纵系统随动性能研究

    陈德鑫; 李松松; 吴亚军


    In this paper, according to the bond graph theory, a calculation model for the clutch operating system with hydraulic control and gas power—assistance of a heavy duty vehicle is established in AMESim. Through this model, the key factors and key structural design parameters that affect the servo performance of the system are analyzed. Results show that preload of the line diameter and pressure control valve exerts great influence on pump retraction time. Moreover, the retraction time of the operating system is greatly influenced by diameter of the exhaust port of the power—assist pump, preload of the hydraulic controlled pressure valve as well as preload of the pressure control valve. Finally, with regard to actual malfunction cases of the servo performance of the clutch operating system, causes for failures in different malfunction models are found.%基于键合图理论,采用AMESim软件建立了某重型车离合器液压气助力操纵系统的计算模型,并利用该模型分析了影响离合器操纵系统随动性能的关键因素及关键结构设计参数.结果表明,管路直径、气压控制阀的预紧力对总泵回位时间影响显著;助力泵排气口直径、液控气压阀预紧力以及气压控制阀的预紧力对操纵系统回位时间影响显著.针对离合器操纵系统随动性能问题的实际故障案例,找到了不同故障模式的失效原因.

  13. 基于模糊PID控制的水轮机调节系统应用与仿真研究%Application and simulation of hydraulic turbine regulation system based on fuzzy PID control

    杨科科; 王臻卓


    Aiming at the nonlinear, time variable and great inertia characteristics of hydraulic turbine regulation system, a precise mathematical model is built to study the basic principles of fuzzy control and fuzzy control algorithm in the paper. Based on this, the fuzzy PID control model of hydraulic turbine regulation system is constructed and fuzzy controller suitable for hydro-generating set is designed. Finally, the simulation is done using Matlab. The research shows that compared with conventional PID control algorithm, the regulation characteristics of hydro-generating unit with the introduction of fuzzy PID control are improved remarkably and has a good dynamic quality.%针对水轮机调节系统的非线性、时变性及大惯性等特点,建立了其较为精确的数学模型,研究了模糊控制的基本原理,在此基础上构建了水轮机调节系统的模糊PID控制模型,并设计了适合水轮发电机组的模糊控制器,最后利用Matlab软件做了深入细致的仿真研究.研究表明,与常规的PID控制算法相比,引入模糊PID控制的水轮发电机组的调节特性得到了明显改善,并具有良好的动态品质.

  14. 振动压路机液压系统研究%On the Hydraulic Driving System Based on Full Hydraulic Vibratory Roller

    杨平; 许炳照


    According to the application of hydraulic control technology of full hydraulic vibratory roller,the paper presents a design scheme of how to select hydraulic driving pumps and the rotators for the hydraulic component parts.Before selecting the methods of the hydraulic driving pumps and the rotators,the design scheme of the hydraulic system power and the engine should be mated properly,so as to determine the data of full hydraulic vibratory roller.%对全液压振动压路机的液压系统进行配置设计,在确定液压泵及液压马达型号规格后,计算液压系统功率与整机的功率合理匹配,从而确定全液压振动压路机各液压系统的参数,完成整机液压系统的合理配置。

  15. A Model Predictive Control Approach for Fuel Economy Improvement of a Series Hydraulic Hybrid Vehicle

    Tri-Vien Vu


    Full Text Available This study applied a model predictive control (MPC framework to solve the cruising control problem of a series hydraulic hybrid vehicle (SHHV. The controller not only regulates vehicle velocity, but also engine torque, engine speed, and accumulator pressure to their corresponding reference values. At each time step, a quadratic programming problem is solved within a predictive horizon to obtain the optimal control inputs. The objective is to minimize the output error. This approach ensures that the components operate at high efficiency thereby improving the total efficiency of the system. The proposed SHHV control system was evaluated under urban and highway driving conditions. By handling constraints and input-output interactions, the MPC-based control system ensures that the system operates safely and efficiently. The fuel economy of the proposed control scheme shows a noticeable improvement in comparison with the PID-based system, in which three Proportional-Integral-Derivative (PID controllers are used for cruising control.

  16. 冷带轧机液压AGC系统过程优化级计算机控制%Research on Computer Control of Process Optimization Level in Hydraulic AGC System of Cold Rolling Mill

    孙孟辉; 王益群


    冷带轧机的轧制过程是较为复杂的物理过程,因此液压AGC(Automatic Gauge Control)系统对冷带轧机成品带钢的厚度精度起着重要的作用。针对300可逆冷带轧机,进行了过程优化级计算机控制的研究,开发出了液压AGC系统的过程优化级计算机控制系统。液压AGC系统的过程优化级计算机控制,可以实现轧制规程的计算、过程控制级所需设定值的设定、轧制过程数据的采集以及人机界面的显示等功能。同时,进行了轧制试验。%Rolling process of the cold rolling mill is a complicated physical process, so the hydraulic AGC system is very important to the thickness precision of strips of cold rolling mill. In this paper, the computer control of process optimization level was researched, and the computer control system of process optimization level was developed, aiming at 300 reverse cold rolling mill. By the computer control of process optimization level of the hydraulic AGC, it can realize the calculation of rolling schedule, the set of setting value needed by the process control level, the data acquisition of rolling process and the display of human-computer interface. At the same time, the rolling experiment was carried out, and the experiment result implied that it could eliminate the thickness error of strips effectively, adopting the provided computer control's strategy of the process optimization level.

  17. Project calculation of the steering mechanism hydraulic servo control in motor vehicles

    Zoran Đukan Majkić


    Full Text Available Hydraulic servo controls are designed to facilitate rotation in place without providing increased ppower to steering wheels. In the initial design phase, the dimensions required for control systems are usually obtained through the calculation of their load when wheels rotate in place, where the torque is calculated empirically. The starting point in the project calculation is thus to determine the hydraulic power steering torque torsional resistance which is then used to determine the maximum value of force i.e. the torque on the stering wheel. The calculation of the control system servo control consists of determining the basic parameters, the required pump capacity, the main dimensions of the hub and the  pipeline and the conditions for the stability of the system control mechanism. Introduction The aim of the calculation of the steering control system is to determine the basic parameters of its components which ensure the fulfilment of requirements of the control system. Calculations are performed in several stages with a simultaneous  detailed constructive analysis of the control system leading to the best variant. At each stage, design and control calculations of the hydraulic servo of the steering mechanism are performed. The design allows the computation to complete the selection of basic dimensions of the amplifer elements, starting from the approved scheme and the basic building loads of approximate values. Calculations control is carried out to clarify the structural solution and to obtain the output characteristics of the control amplifier which are applied in the  estimation of  potential properties of the structure. Project calculation Baseline data must be sufficiently reliable, ie. must correspond to the construction characteristics of the vehicle design and the control system as well as to service conditions..A proper deterimination of the torque calculation of torsional resistance in wheels is of utmost importance. Moment of

  18. Application of Fuzzy Clustering in Modeling of a Water Hydraulics System

    Zhou, Jianjun; Kroszynski, Uri


    This article presents a case study of applying fuzzy modeling techniques for a water hydraulics system. The obtained model is intended to provide a basis for model-based control of the system. Fuzzy clustering is used for classifying measured input-output data points into partitions. The fuzzy mo...

  19. Design on Automatic Heave Compensation Hydraulic System of Remotely Operated Vehicle Based on Neuron PID Control%基于神经元PID的水下机器人自动升沉补偿液压系统设计

    何新英; 吴家鸣


    针对母船的升沉运动会影响到带缆遥控水下机器人的安全作业和收放功能,提出了利用液压绞车进行水下机器人自动升沉补偿的方案。设计了带缆遥控水下机器人升沉补偿液压系统,控制系统采用了神经元自适应PID控制算法。并在Matlab中进行了仿真,仿真结果表明,该系统能够较好的实现水下机器人的升沉补偿运动。%The supporting ship heave motion affects the remotely operated vehicle safety operation and storage function,using hydraulic winch for automatic heave compensation of ROV was presented in this paper,The heave compensation hydraulic system of ROV has been designed, which the neuron adaptive PID control algorithm has been adopted. And has been simulate in mat lab,the simulation result show that the system can realize the ROV heave compensation movement.

  20. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.


    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic or pneumatic power and control-materials and... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component (such as pipe runs, fittings, flanges, and standard valves) for hydraulic or pneumatic power and...

  1. Internal Leakage Fault Detection and Tolerant Control of Single-Rod Hydraulic Actuators

    Jianyong Yao


    Full Text Available The integration of internal leakage fault detection and tolerant control for single-rod hydraulic actuators is present in this paper. Fault detection is a potential technique to provide efficient condition monitoring and/or preventive maintenance, and fault tolerant control is a critical method to improve the safety and reliability of hydraulic servo systems. Based on quadratic Lyapunov functions, a performance-oriented fault detection method is proposed, which has a simple structure and is prone to implement in practice. The main feature is that, when a prescribed performance index is satisfied (even a slight fault has occurred, there is no fault alarmed; otherwise (i.e., a severe fault has occurred, the fault is detected and then a fault tolerant controller is activated. The proposed tolerant controller, which is based on the parameter adaptive methodology, is also prone to realize, and the learning mechanism is simple since only the internal leakage is considered in parameter adaptation and thus the persistent exciting (PE condition is easily satisfied. After the activation of the fault tolerant controller, the control performance is gradually recovered. Simulation results on a hydraulic servo system with both abrupt and incipient internal leakage fault demonstrate the effectiveness of the proposed fault detection and tolerant control method.

  2. Effects of hedgerow systems on soil moisture and unsaturated hydraulics conductivity measured by the Libardi method

    S . Prijono


    Full Text Available The hedgerow systems are the agroforestry practices suggesting any positive impacts and negative impacts on soil characteristics. This study evaluated the effects of hedgerows on the unsaturated hydraulic conductivity of soil with the Libardi method approach. This study was conducted in North Lampung for 3 months on the hedgerow plots of Peltophorum dassyrachis (P, Gliricidia sepium (G, and without hedgerow plot (K, with four replications. Each plot was watered as much as 150 liters of water until saturated, then the soil surface were covered with the plastic film. Observation of soil moisture content was done to a depth of 70 cm by the 10 cm intervals. Soil moisture content was measured using the Neutron probe that was calibrated to get the value of volumetric water content. Unsaturated hydraulic conductivity of soil was calculated by using the Libardi Equation. Data were tested using the analysis of variance, the least significant different test (LSD, Duncan Multiple Range Test (DMRT, correlation and regression analysis. The results showed that the hedgerow significantly affected the soil moisture content and unsaturated hydraulic conductivity. Soil moisture content on the hedgerow plots was lower than the control plots. The value of unsaturated hydraulic conductivity in the hedgerow plots was higher than the control plots. Different types of hedgerows affected the soil moisture content and unsaturated hydraulic conductivity. The positive correlation was found between the volumetric soil moisture content and the unsaturated hydraulic conductivity of soil.

  3. 拖拉机新型线控液压转向系统的研究与仿真%Study and Simulation on New- type Wire -controlled Hydraulic Steering System of Tractor

    常江雪; 鲁植雄; 白学峰


    The author conducted the overall design for the wire - controlled hydraulic steering system of tractor, analyzed its structure and working principle in detail, and obtained the optimal control algorithm of the system through the comparative analysis. The fuzzy control algorithm was used to realize the closed - loop control technique for the steering of the front wheel in the system. In the end, Matlab/simulink was used for the simulation of the entire system. The simulation got the response curve of oil cylinder displacement , and verified the accuracy of the design for this system.%对拖拉机线控液压转向系统进行了总体设计,详细分析了其结构组成和工作原理,并通过对比分析得出了系统的最优控制算法.采用模糊控制作为系统的控制算法,实现了前轮转角的闭环控制技术;最后采用Matlab/simulink对整个系统进行仿真,得出了油缸位移的响应曲线,验证了系统设计的准确性.

  4. Method for achieving hydraulic balance in typical Chinese building heating systems by managing differential pressure and flow

    Zhang, Lipeng; Xia, Jianjun; Thorsen, Jan Eric;


    Hydraulic unbalance is a common problem in Chinese district heating (DH) systems. Hydraulic unbalance has resulted in poor flow distribution among heating branches and overheating of apartments. Studies show that nearly 30% of the total heat supply is being wasted in Chinese DH systems due...... to a lack of pressure and flow control. This study investigated using pre-set radiator valves combined with differential pressure (DP) controllers to achieve hydraulic balance in building distribution systems, and consequently save energy and reduce the emissions. We considered a multi-storey building...

  5. The study on measures to improve the reliability of the hydraulic systems of shearers

    袁辉; 徐龙江; 田大宝; 赵燕玲


    The authors indicate that the failure of hydraulic systems of shearers can drop greatly, its' reliability and service life can be increased by the use of a field oil contamination analyser and filter device to control the oil contamination of the hydraulic systems of shearers. Experimental provement of silting-theory contamination analyser are carried out. The filter effect of portable hydraulic driving oil-filter model YLJ-21 is examinationed in laboratory and field experiment. From January to August 1992, on-site experimental research using a silting-theory contamination analyser and oil-filter model YLJ-21 to control the oil contamination was carried out in the Datong Coat Mining Bureau.

  6. Teaching Thermal Hydraulics & Numerical Methods: An Introductory Control Volume Primer

    D. S. Lucas


    A graduate level course for Thermal Hydraulics (T/H) was taught through Idaho State University in the spring of 2004. A numerical approach was taken for the content of this course since the students were employed at the Idaho National Laboratory and had been users of T/H codes. The majority of the students had expressed an interest in learning about the Courant Limit, mass error, semi-implicit and implicit numerical integration schemes in the context of a computer code. Since no introductory text was found the author developed notes taught from his own research and courses taught for Westinghouse on the subject. The course started with a primer on control volume methods and the construction of a Homogeneous Equilibrium Model (HEM) (T/H) code. The primer was valuable for giving the students the basics behind such codes and their evolution to more complex codes for Thermal Hydraulics and Computational Fluid Dynamics (CFD). The course covered additional material including the Finite Element Method and non-equilibrium (T/H). The control volume primer and the construction of a three-equation (mass, momentum and energy) HEM code are the subject of this paper . The Fortran version of the code covered in this paper is elementary compared to its descendants. The steam tables used are less accurate than the available commercial version written in C Coupled to a Graphical User Interface (GUI). The Fortran version and input files can be downloaded at

  7. 兆瓦级风力机节能型电-液复合变桨距系统的设计与仿真研究%Design and Simulation Study of Energy-saving Electro-hydraulic Composite Pitch Control System for Megawatt-class Wind Turbine

    刘军龙; 代晶辉; 吕凤池; 李阳; 赵进宝; 姜继海


    针对现有的电动变桨距系统和液压变桨距系统所存在的问题,将直驱式容控电液伺服技术与风力机变桨距系统结合,提出了一种节能型电-液复合变桨距系统.并以1.5 MW风力机为例,完成对其变桨距系统的设计、元件选型和Simulink仿真,分析了该节能型电-液复合变桨距系统在大功率风力机上应用的可行性.%Aimed at the existing problem of present electric pitch control system and hydraulic pitch control system,by combining the direct drive volume control electro-hydraulic servo technique and wind turbine pitch control system,a new kind of energy-saving electro-hydraulic composite pitch control system was proposed.By taking the 1.5 mega-watt wind turbine as an example,its pitch control system design,parts selection and Simulink Simulation were accomplished.The possibility of the application of this energy-saving electro-hydraulic composite pitch control system on high-power wind turbines was analyzed.

  8. Charging valve of the full hydraulic braking system

    Jinshi Chen


    Full Text Available It is known that the full hydraulic braking system has excellent braking performance. As the key component of the full hydraulic braking system, the parameters of the accumulator charging valve have a significant effect on the braking performance. In this article, the key parameters of the charging valve are analyzed through the static theoretical and an Advanced Modeling Environment for performing Simulation of engineering systems (AMESim simulation model of the dual-circuit accumulator charging valve is established based on the real structure parameters first. Second, according to the results of the dynamic simulation, the dynamic characteristics of the charging pressure, the flow rate, and the frequency of the charging valve are studied. The key parameters affecting the serial production are proposed and some technical advices for improving the performance of the full hydraulic system are provided. Finally, the theoretical analysis is validated by the simulation results. The comparison between the simulation results and the experimental results indicates that the simulated AMESim model of the charging valve is accurate and credible with the error rate inside 0.5% compared with the experimental result. Hence, the performance of the charging valve meets the request of the full hydraulic braking system exactly.

  9. 船携式海面溢油回收机液压控制系统设计与实现方法%The Design and Realization of Hydraulic Control System for the Ship Carrying Oil Spill Recycling Machine

    王世刚; 杨前明; 郭建伟; 刘宗江


    It is one of the effective ways that the ship carrying nil spill recycling system realizes oil spill recycling and reduces oil spill pollution hazards. The design proposals of hydraulic control system for ship carrying oil spill recovery have been given, and the detection methods of the system parameters for the speed control of hydraulic motor, oil level of skimmer, oil temperature of oil tank and so on also been put forward in this paper aiming at the dynamic bevel oil spill recycling skimmer. The resuh of the actual operation shows that the design proposals are reasonable and reliable, which provides a reference for the design of oil spill recycling equipment.%船携式海面溢油回收系统是实现海洋溢油回收,降低溢油污染危害的有效途径之一。本文以动态斜面式溢油回收撇油器为对象,给出了船携式海面溢油回收液压控制系统的设计方案,提出了溢油回收机液压系统液压马达调速、撇油器油位、油箱油温等参数的检测方法。系统运行结果表明:本文给出的方案设计合理、运行可靠,为海面溢油回收设备设计提供了借鉴。

  10. Understanding the Space Shuttle Main Engine Hydraulic Actuation System and Reviewing Its Evolution

    McWade, Robert J.; Minor, Robert B.; McNutt, Leslie M.


    The complex engine start and thrust control requirements of the Space Shuttle Main Engine (SSME) require unique valve, actuator and control system hardware. The Hydraulic Actuation System (HAS) was designed, developed, and now operates to meet tight engine control requirement limits to assure safe, reliable and correct engine thrust at all times. The actuator is designed to be fail safe and fail operate in the areas where redundancy is important. The HAS has an additional pneumatic operating capability that insures a safe sequential closure of all actuators and propellant valves in the event of the loss of hydraulic system pressure or loss of electrical closed loop control of the actuator. The objective of this paper is to provide a complete description of the actuator s internal operating system, along with its interaction with all SSME system interfaces. Additionally the paper addresses the challenges, problems identified, and corrected, and lessons learned, during the course of the almost 35 years of engine operation.


    Teodor Eugen Man


    Full Text Available This paper presents two examples of exploitation of water energy that can be used in the irrigation field. First of theseexamples is the hydraulic transformer type A. Barglazan used for irrigation, pumped water is taken directly from theriver’s well, using a hydraulic pump which simultaneously carried out a double transformation in this way: hydraulicenergy into mechanic energy and mechanical energy into hydraulic energy. Technology preparation and devices designwas done in record time, seeing that this constructive solution is more robust, reliable and with improved energyperformance versus the laboratory prototype. The experimental research which was made at 1:1 scale proved theirgood function over time. Another example is the hydraulic hammer (hydraulic pump that uses low-head energy topump water, with a global efficiency of about 10 - 50%. Currently, the new situation of private ownership of landprovides conditions for new pumping microstations to be made where irrigation is necessary and optimal hydrauliclocations exist.

  12. FOREWORD: The XXV IAHR Symposium on Hydraulic Machinery and Systems marks half a century tradition

    Susan-Resiga, Romeo


    far from the best efficiency regime. The traditional partnership with the Romanian Academy - Timisoara Branch, Laboratory for Hydrodynamics and Cavitation, led to complex projects that combine both basic theoretical developments with advanced experimental investigations leading to practical engineering solutions for modern hydraulic machines. The International Association of Hydro-Environment Engineering and Research (IAHR) celebrates its 75th anniversary this year. IAHR particularly promotes the advancement and exchange of knowledge through working groups, specialty symposia, congresses, and publications on water resources, river and coastal hydraulics, risk analysis, energy, environment, disaster prevention, industrial processes. The IAHR - Committee on Hydraulic Machinery and Systems deals with the advancement of technology associated with the understanding of steady and unsteady flow characteristics in hydraulic machinery and conduit systems connected to the machinery. The technology elements include the fluid behaviour within machine components, hydro-elastic behaviour of machine components, cavitation, and two phase flow in turbines and pumps, hydraulic machine and plant control systems, the use of hydraulic machines to improve water quality, and even considerations to improve fish survival in their passage through hydro plants. The main emphases of the IAHR Committee on Hydraulic Machinery and Systems are to stimulate research and understanding of the technologies associated with hydraulic machinery and to promote interaction between the machine designers, machine users, the academic community, and the community at large. Hydraulic machinery is both cost effective and environmentally responsible. The increasing atmospheric content of carbon dioxide related to pollution from thermal power plants, is one of the most significant threats to our global ecology. The problem is exacerbated by the need for increased energy production in third world countries. This

  13. Interval Type-2 fuzzy position control of electro-hydraulic actuated robotic excavator

    Hassan Mohammed Yousif; Kothapalli Ganesh


    This paper deals with fuzzy intelligent position control of electro-hydraulic activated robotic excavator for the control of boom,arm and bucket axes.Intelligent control systems are required to overcome undesirable stick-slip motion,limit cycles and oscillations.Models of electro-hydraulic servo controlled front end loader excavators are highly nonlinear.The nonlinear model accounts for fluid flow rate of valve,pump hydraulics,and friction forces.The friction forces are modelled by Coulomb,viscous and Stribeck function.Interval Type-2 Fuzzy Logic Controller (IT2FLC) is used to study the time domain position responses of axes in the presence of external applied load.It has the ability to control the position of eachof the three axes with minimum actuator position errors.Models presented are accurate and study the dynamics of the actuator and load.To improve the transient behaviour of the robotic excavator,we eliminated jitter of the bucket movement in the presence of nonlinearities.

  14. 49 CFR 571.105 - Standard No. 105; Hydraulic and electric brake systems.


    ... signal or signals. Electric vehicle or EV means a motor vehicle that is powered by an electric motor... or control signals in an antilock brake system, or a total functional electrical failure in a... 49 Transportation 6 2010-10-01 2010-10-01 false Standard No. 105; Hydraulic and electric...

  15. 泵控电液混合驱动系统在板料折弯机上的应用研发%The application and exploration of pump-control electro-hydraulic driving system in press brake for sheet metal

    李振光; 汪立新; 温峰虎; 雷斌华; 茅问宇


    The electric and hydraulic principles of the pump-control electro-hydraulic driving system have been introduced in the text, as well as the advantages of pump-control press brake comparing with the conventional one. It is pointed out that the application of pump-control electro-hydraulic driving system is more widely, which has a broad marketing prospect.%介绍了泵控电液混合驱动系统的电气原理、液压原理,以及与传统折弯机相比泵控折弯机的诸多优点,指出泵控电液混合驱动系统的应用将越来越广泛,具有广阔的市场前景.

  16. Application of a load-bearing passive and active vibration isolation system in hydraulic drives

    Unruh, Oliver; Haase, Thomas; Pohl, Martin


    Hydraulic drives are widely used in many engineering applications due to their high power to weight ratio. The high power output of the hydraulic drives produces high static and dynamic reaction forces and moments which must be carried by the mounts and the surrounding structure. A drawback of hydraulic drives based on rotating pistons consists in multi-tonal disturbances which propagate through the mounts and the load bearing structure and produce structure borne sound at the surrounding structures and cavities. One possible approach to overcome this drawback is to use an optimised mounting, which combines vibration isolation in the main disturbance direction with the capability to carry the reaction forces and moments. This paper presents an experimental study, which addresses the vibration isolation performance of an optimised mounting. A dummy hydraulic drive is attached to a generic surrounding structure with optimised mounting and excited by multiple shakers. In order to improve the performance of the passive vibration isolation system, piezoelectric transducers are applied on the mounting and integrated into a feed-forward control loop. It is shown that the optimised mounting of the hydraulic drive decreases the vibration transmission to the surrounding structure by 8 dB. The presented study also reveals that the use of the active control system leads to a further decrease of vibration transmission of up to 14 dB and also allows an improvement of the vibration isolation in an additional degree of freedom and higher harmonic frequencies.

  17. Fault Analysis and Improvement of Hydraulic-controlled Butterfly-valve Control System of Main Pump Outlet of Wanjiazhai YRDP(Yellow River Diversion Project)%万家寨引黄工程主泵出口液控蝶阀控制系统故障分析与改进



    山西省万家寨引黄工程一期泵站泵组出水侧液控蝶阀控制系统采用传统的接触式机械行程开关,由于蝶阀设备运行在大振动、高潮湿环境下,接触式行程开关损坏频度较高,经常导致液控蝶阀行程控制失效或错误,致使泵组非正常停运。在分析液控蝶阀行程开关故障原因的基础上,提出采用非接触式磁控开关进行技术改造的方案,工程实践证明改造工作较好地解决了液控蝶阀的行程控制问题。%The hydraulic-controlled butterfly-valve control system mounted on pump outlet side in the pumping station of Shanxi Wanjiazhai YRDP phase 1 is controlled by the traditional mechanical contact travel switch. The butterfly-valve operates in large vibration and high humidity environment, the contact travel switch is damaged frequently, often leading to the failures and mistakes of the travel control of hydraulic-controlled butterfly-valve, and causing the the abnormal shutdown of the pump unit. Based on analyzing the reasons of the faults of the travel switch of hydraulic-controlled valve, this paper puts forward a technical transformation scheme of adopting the non-contact magnetic-controlled switch. The engineering practice proves that the technical transformation has better solved the problem of the travel control of hydraulic-control butterfly-valve.

  18. 阀控液压马达速度伺服系统仿真分析%Simulation of the Hydraulic Motor of Speed Servo System Controlled by Valve

    贾文铜; 周瑞祥; 张忠


    针对干扰力矩对阀控液压马达速度伺服系统的影响,利用结构不变性原理给系统加入了补偿器来消除干扰力矩的影响,同时利用PID控制来提高系统的抗干扰性.仿真表明,在利用结构不变性原理后再通过PID控制可以有效提高系统抗干扰能力和控制精度.%Aiming at the interfere moment affecting the hydraulic motor of speed servo system controlled by valve,the structure unchangeable principle was applied to eliminate the effect of the interfere moment and PID control was also managed to enhance the anti-jamming of the system, The simulation indicates that the application of the PID controll after the application of structure unchangeable principle can effectively improve the anti-jamming ability and control precision.

  19. The hydraulic lifting system for the main magnets of CYCIAE-30 cyclotron

    Zhao Zhen Lu; Chen Rong Fan; Chu Cheng Jie


    The oil-line structure, control system and their working principles of the hydraulic lifting system for the main magnets of CYCIAE-30 cyclotron are introduced. The six years practice proves that the specification of the system matches the requirements: the oil cylinder maximum stroke of 850 mm, the eight slot positioning dowels repositioning accuracy of +-0.01 mm, the two oil cylinders moving in step accuracy of 5-10 mm. The system is safe, reliable and easy to be operated

  20. 基于单神经元-PID的液压变桨距控制系统的设计%The Design of Hydraulic Pitch-control System Based on Single Neuron Cell PID


    An intelligent PID control calculation is developed using single neuron,combining the advantages such as adaptability, self-learning, simple structure, short weight learning time, small computational amount and strong ro-bustness. Through the experimental study, it indicated that the hydraulic pitch-control system based on single neuron cell PID can better meet the requirements of nonlinear dynamics of the system and parameter time-variation than the classical PID control system.%  提出的单神经元-PID液压变桨距控制方法,结合了单神经元自适应性,自学习,结构简单,权值学习时间短,计算量小,鲁棒性强等优点,并通过实验,对该控制方法进行了验证,证明了其相比常规PID控制的优越性,能更好地满足风力变桨距系统的非线性,参数时变性的要求。

  1. The 25 kWe solar thermal Stirling hydraulic engine system: Conceptual design

    White, Maurice; Emigh, Grant; Noble, Jack; Riggle, Peter; Sorenson, Torvald


    The conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to a 11 meter test bed concentrator is documented. A manufacturing cost assessment for 10,000 units per year was made. The design meets all program objectives including a 60,000 hr design life, dynamic balancing, fully automated control, more than 33.3 percent overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk.

  2. Scheme Design for the Giant Forging Hydraulic Press Active Synchronous Control System%巨型模锻液压机主动同步控制方案的设计



    The synchronous control system is the essential device to the giant forging hydraulic press. Its synchronization control performance will directly determine product quality. The main causes of working cylinder asynchronism and its effect on synchronous control performance were analyzed. According to the practical problems of synchronous control application, an active synchronism control scheme was proposed based on multi-point driver.%同步控制系统是巨型模锻液压机上必备的关键装置,其同步控制性能的好坏将直接决定产品的质量.在分析主工作缸不同步的成因及对同步控制性能影响的基础上,根据巨型模锻液压机同步控制的实际应用问题,提出一种基于多点驱动的主动同步控制方案.

  3. Study on the Energy-Regeneration-based Velocity Control of the Hydraulic-Hybrid Vehicle

    SONG Yunpu


    Full Text Available This paper simplifies the energy regenerationbased vehicle velocity system of the hydraulichybrid businto a process in which the extension rod of the hydraulic cylinder drives the secondary-element variable delivery pump/motor to change its displacement. This process enables braking of the vehicle and also allows recovery of energy. The stability, energy efficiency and other characteristics of the system are studied based on analysis of mathematical models of the vehicle velocity control. The relevant controller is designed to study effects of the controller on system characteristics. The vehicle velocity control module of the energy regeneration system is stable and able to recovery the inertia energy generated in vehicle braking. After the controller intended to improve response speed is added, system response becomes quicker but energy recovery rate declines.


    Shi Wenku; Min Haitao; Dang Zhaolong


    6-DOF non-linear mechanics model of powerplant hydraulic mount system is established. Optimum design of the powerplant hydraulic mount system is made with the hydraulic mount parameters as variables and with uncoupling of energy, rational disposition of nature frequency and minimum of reactive force at mount's location as objective functions. And based on the optimum design, software named ODPHMS (optimum design of powerplant hydraulic mount system) used in powerplant mount system optimum design is developed.

  5. Hydraulics of sprinkler and microirrigation systems

    The fluid dynamics of sprinkler and microirrigation systems are complex. Water moves dynamically from the water source through the pump into the pipe network. Water often goes through a series of screens and filters depending on the source and type of irrigation system. From the pipe network, water ...

  6. An Approach to automatically optimize the Hydraulic performance of Blade System for Hydraulic Machines using Multi-objective Genetic Algorithm

    Lai, Xide; Chen, Xiaoming; Zhang, Xiang; Lei, Mingchuan


    This paper presents an approach to automatic hydraulic optimization of hydraulic machine's blade system combining a blade geometric modeller and parametric generator with automatic CFD solution procedure and multi-objective genetic algorithm. In order to evaluate a plurality of design options and quickly estimate the blade system's hydraulic performance, the approximate model which is able to substitute for the original inside optimization loop has been employed in the hydraulic optimization of blade by using function approximation. As the approximate model is constructed through the database samples containing a set of blade geometries and their resulted hydraulic performances, it can ensure to correctly imitate the real blade's performances predicted by the original model. As hydraulic machine designers are accustomed to do design with 2D blade profiles on stream surface that are then stacked to 3D blade geometric model in the form of NURBS surfaces, geometric variables to be optimized were defined by a series profiles on stream surfaces. The approach depends on the cooperation between a genetic algorithm, a database and user defined objective functions and constraints which comprises hydraulic performances, structural and geometric constraint functions. Example covering optimization design of a mixed-flow pump impeller is presented.

  7. Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control

    You, Seung Han [Hyundai Motor Company, Seoul (Korea, Republic of); Hahn, Jin Oh [University of Alberta, Edmonton (Canada)


    By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today's passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems.

  8. Hydraulic Equalizing Valve with Total Power Control%液压泵总功率控制的均压阀

    杨莽; 王林


    The design and practical use of the hydraulic system, the two variable piston pump together in the same hydraulic system and to ensure consistency and to achieve the two hydraulic displacement of the total power control. The general use of two cross-pump control mode, the disadvantage is that the two hydraulic control cross consistency and total power control is poor, and it is difficult to ensure the con-sistency of the two hydraulic pumps. In this paper, by designing a pressure equalization valve to achieve the two hydraulic control. The re-sults showed that the equalizing valve can well ensure the consistency of the two hydraulic pumps and total power control.%在液压系统的设计和实际使用过程中,两台变量柱塞液压泵共同作用于同一液压系统并保证两台液压泵排量一致且要实现总功率控制.目前一般采用两台液压泵交叉控制的方式,交叉控制的缺点是两台液压泵的一致性和总功率控制效果差,且很难保证两台液压泵的一致性.该文通过设计一种均压阀,来实现两台液压泵的控制.结果表明,均压阀能够很好地保证两台液压泵的一致性和总功率控制.

  9. Thermo-hydraulic modeling of flow in flare systems

    Meindinyo, Remi-Erempagamo T.


    Flare systems play a major role in the safety of Oil and Gas installations by serving as outlets for emergency pressure relief in case of process upsets. Accurate and reliable estimation of system thermo-hydraulic parameters, especially system back-pressure is critical to the integrity of a flare design. FlareNet (Aspen Flare System Analyzer Version 7) is a steady state simulation tool tailored for flare system design and has found common use today. But design based on steady state modelin...

  10. Application of Hydraulic Model to Improvement of Flood Control Capacity of Rainwater System%水力模型用于提高雨水系统防汛能力的研究

    祁继英; 丁敏; 吴佳


    利用排水系统模型对上海已建的平阳、平吉雨水系统进行客观、全面的分析.从地区防汛角度,评估按一年一遇标准设计建设排水系统的暴雨积水风险,运用二维地表漫溢模型定量分析了积水范围、历时等地表积水特性,并研究了降雨过程强度、系统管道动态水力特性、泵站运行等系统相关要素,提出了优化泵站日常运行模式思路,进一步评估了在优化泵站运行工况条件下,系统实际可承受的降雨强度与负荷,提出了应对超标准降雨、减缓系统积水风险的泵站运行建议,为防汛调度提供决策支持.%The objective and comprehensive analysis of Pingyang and Pingji stormwater systems were performed using drainage hydraulic model.From the regional flood control perspective,the risks of stormwater drainage systems designed and constructed based on one-year storm were evaluated.The characteristics of surface ponding like ponding range and duration were analyzed using 2D surface overflow model,and the relevant elements such as rainfall intensity,dynamic hydraulic characteristics of the system pipes and operation of pumping stations were studied.The optimal daily operation mode ideas of the pumping stations were proposed.The rainfall intensity and load which the system could withstand under the optimal operation conditions of the pumping stations were assessed.The suggestions for coping with excessive rainfall and decreasing system ponding risk were offered to provide decision-making support for flood control dispatch.

  11. 基于模糊神经网络的电液位置伺服系统控制%Electro-hydraulic Position Servo System Control Based on Fuzzy-neural Network

    刘坤; 高少平


    In this paper, a kind of hybrid control structure is designed using the fuzzy neural of combining the T-S fuzzy model and the RBF neural theory to solve these problems which are about the on-line realization of model and the on-line design of controller in traditional adaptive control. The work above is to track the output of the uncertain unlinear system with high accuracy. Through using the supervisor, the common problem of poor real-time in fuzzy neural control is come over. With a robust feedback controller, the stability of closed-loop system in fuzzy neural model learning earlier is guaranteed. On the other hand, this paper utilizes this scheme to an electro-hydraulic position servo system simulation and achieves satisfactory results.%采用将T-S模型与RBF神经网络相结合的网络结构,提出一种复合式控制方案,以解决传统自适应控制中模型的在线辨识和控制器的在线设计问题,以达到对不确定非线性系统的高精确度输出跟踪控制;通过引入运行监控器,克服模糊神经网络控制方法通常存在的实时性差的问题;同时,利用一个鲁棒反馈控制器,来保证模糊神经网络模型学习初期闭环系统的稳定性.并应用于电液位置伺服系统的仿真研究中,获得满意的控制效果.

  12. New method to improve dynamic stiffness of electro-hydraulic servo systems

    Bai, Yanhong; Quan, Long


    Most current researches working on improving stiffness focus on the application of control theories. But controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated, so the control action is lagged. Thus dynamic performance against force disturbance and dynamic load stiffness can’t be improved evidently by advanced control algorithms. In this paper, the elementary principle of maintaining piston position unchanged under sudden external force load change by charging additional oil is analyzed. On this basis, the conception of raising dynamic stiffness of electro hydraulic position servo system by flow feedforward compensation is put forward. And a scheme using double servo valves to realize flow feedforward compensation is presented, in which another fast response servo valve is added to the regular electro hydraulic servo system and specially utilized to compensate the compressed oil volume caused by load impact in time. The two valves are arranged in parallel to control the cylinder jointly. Furthermore, the model of flow compensation is derived, by which the product of the amplitude and width of the valve’s pulse command signal can be calculated. And determination rules of the amplitude and width of pulse signal are concluded by analysis and simulations. Using the proposed scheme, simulations and experiments at different positions with different force changes are conducted. The simulation and experimental results show that the system dynamic performance against load force impact is largely improved with decreased maximal dynamic position deviation and shortened settling time. That is, system dynamic load stiffness is evidently raised. This paper proposes a new method which can effectively improve the dynamic stiffness of electro-hydraulic servo systems.

  13. The Causes and Control of Startup Impact of Hydraulic Systems with High Inertia Loads%大惯性负载液压系统启动冲击成因及控制

    吴万荣; 秦伟业; 梁向京; 娄磊


    大惯性负载液压系统在启动过程中往往产生较大的冲击与振动。分析大惯性负载启动冲击的成因,通过把进油路容腔分为前、后两容腔分别进行数学建模,推导出启动冲击压力的估算公式。根据启动冲击成因提出控制方法,即溢流阀的开启压力前期按照线性规律增加,中后期按照对数函数规律增加,主阀芯按照线性规律开启。把该控制方法运用在大惯性负载系统中进行仿真研究,以执行器进油腔压力升高特性作为主要研究指标。仿真表明,采用该控制方法,可以减小执行器进油腔的最高冲击压力和压力波动幅值,使启动过程更平稳。%The hydraulic system with high inertia loads usually has great startup impact and vibration. In this paper, the reason of the startup impact was analyzed. The mathematical models of the front part and the rear part of the oil cavity of the hydraulic system were established respectively, and the estimation formula of the startup impact pressure was deduced. According to the Causes of the startup impact, a control method was put forward. In this method, the opening pressure of the relief valve was set to increase linearly earlier and increase in accordance with the logarithmic law later, and the main valve core opened linearly. This control method was also applied to the simulation of the high inertia load system with the pressure rising characteristics in the inlet oil cavity as the main output. The simulation result shows that this control method can reduce the maximum shock pressure and the amplitude of pressure fluctuation in the inlet oil cavity, and make the startup process smoother.

  14. The Integration of an Electro-Hydraulic Manipulator Arm into a Self-Contained Mobile Delivery System

    M. Borland; S. M. Berry


    The Portable Articulated Arm Deployment System (PAADS) is a remotely controlled vehicle for delivering a tele-operated electro-hydraulic manipulator arm to a field-deployable location. The self-contained system includes a boom vehicle with long reach capability, an electro-hydraulic manipulator arm, closed circuit television (CCTV) systems, and onboard tools. On board power systems consist of a self-contained, propane-fired 8-KW generator and an air compressor for pneumatic tools. The generator provides the power to run the air compressor as well as power to operate the 110-VAC auxiliary lighting system for the video cameras. The separate control console can be located up to 500 ft from the vehicle. PAADS is a fully integrated system, containing all equipment required to perform complex field operations. Hydraulic integration of the manipulator arm into the vehicle hydraulic drive system was necessary to eliminate the tether management of hoses, which extended vehicle operating range, minimized hydraulic pressure losses, and provided the opportunity to go to a radio frequency (RF) control system in the future, thereby eliminating the control cable. This paper presents the key decision points during system development. Emphasis is placed on ease of operator control and not on an intelligent machine approach. In addition, emphasis is placed on the philosophy of remote operation based on sound principles of integration.

  15. The Integration of an Electro-hydraulic Manipulator Arm into a Self-contained Mobile Delivery System

    Borland, Mark Wilson; Berry, Stephen Michael


    The Portable Articulated Arm Deployment System (PAADS) is a remotely controlled vehicle for delivering a tele-operated electro-hydraulic manipulator arm to a field deployable location. The self-contained system includes a boom vehicle with long reach capability, an electro-hydraulic manipulator arm, closed circuit television (CCTV) systems, and onboard tools. On board power systems consist of a self contained, propane fired 8 KW generator and an air compressor for pneumatic tools. The generator provides the power to run the air compressor as well as provide power to operate the 110 VAC auxiliary lighting system for the video cameras. The separate control console can be located up to 500 ft from the vehicle. PAADS is a fully integrated system, containing all equipment required to perform complex field operations. Hydraulic integration of the manipulator arm into the vehicle hydraulic drive system was necessary to eliminate the tether management of hoses, which extended vehicle operating range, minimized hydraulic pressure losses, and provided the opportunity to go to a radio frequency (RF) control system in the future, thereby eliminating the control cable. This paper presents the key decision points during system development. Emphasis is placed on ease of operator control and not on an intelligent machine approach. In addition, emphasis is placed on the philosophy of remote operation based on sound principles on integration.

  16. 液压软管卷盘的控制策略及安全监控系统设计%Control strategy speculation and safety monitoring system design for hydraulic hosereel

    李万莉; 余清福; 薛红梅


    液压软管卷盘是为地下连续墙施工装置的液压系统提供液压油源的重要部件,软管在卷盘马达作用下随着施工装置的动作同步收放.通过对软管收放过程的分析和计算,得到驱动卷盘所需的扭矩和缠绕角度的关系,指导设计软管收放系统的智能控制策略.基于此策略设计液压软管卷盘的安全监控系统,经现场试验效果良好.%As the hydraulic hosereel is a vital component for oil supply to the hydrauliic systems during di-aphram wall construction, the retraction of hoses is actuated by the hosereel motor and synchronized with the action of construction equipment. By analyzing and calculating the hose's retraction process, the relationship between the hosereel's driving torque and winding angle, the intelligent control strategy is accordingly designed for hose's retraction system. Based on the on-site testing,relevant safety monitoring system is proven promising for hosereel design.

  17. Simulation Study on Rotation Control System for Fully-hydraulic Forging Manipulators%全液压有轨锻造操作机旋转位置控制系统仿真研究



    Considering the characteristics of fully-hydraulic forging manipulator control system, the MATLAB/ Simulink-AMESim co-simulation technology was employed to simulate the system. The results show that fuzzy self-tuning PID algorithm-based system can comply with the field environment automatically and can dynamically output adjustable parameters to PID control algorithm; compared with the general PID algorithm, the response curve becomes smooth, and the control system robustness and adaptability get enhanced, as well as the accuracy increased by 10% to 20% together with smaller load and higher precision.%针对400kN/800kN·m全液压有轨锻造操作机旋转控制系统的特点,通过MATLAB/Simulink和AMESim协同仿真技术对全液压有轨锻造操作机旋转液压伺服控制系统进行建模和仿真研究.仿真结果表明:基于模糊控制算法的控制系统可以自动适应全液压有轨锻造操作机的现场工作环境,动态输出PID控制器的各项调节参数,与基于普通PID算法的控制系统相比,增强了控制系统的鲁棒性和适应性;响应速度加快,提高了控制系统的实时性,使全液压有轨锻造操作机的运行更加平稳,控制精度提高了10% ~20%,且负载越小,精度越高.

  18. Process fluids of aero-hydraulic systems and their properties

    I. S. Shumilov


    Full Text Available The article considers process fluids, which are presently applied to aviation hydraulic systems in domestic and world practice. Aviation practice deals with rather wide list of fluids. Based on the technical specification a designer makes the choice of specific fluid for the specific aircraft. Process fluids have to possess the specified properties presented in the article, namely: lubricating properties; stability of physical and chemical characteristics at operation and storage; lowtemperature properties; acceptable congelation temperature; compatibility with materials of units and components of hydraulic systems; heat conductivity; high rigidity; minimum low coefficient of volume expansion; fire-explosion safety; low density. They should also have good dielectric properties, be good to resist to destruction of molecules, have good anticorrosion and antierosion properties, as well as not create conditions for emerging electro-kinetic erosion of spooltype and other precision devices, and a number of other properties.The article presents materials on the oil-based process fluids with + (200-320 °C boiling temperature, gelled by a polymer of vinyl butyl ether, with aging inhibitor and dye for hydraulic systems of the subsonic and transonic aircraft which are combustible, with a temperature interval of use from — 60oС до +125oС. It also describes materials on process fluids, which are based on the mix of polydialkylsiloxane oligomers with organic diester aging inhibitors, and wear-resistant additive to be applied to the hydraulic systems of supersonic aircrafts using a fluid within the temperature interval from - 6О oС to +175oС for a long duration. The fire-explosion safety process fluids representing a mix of phosphoric esters with additives to improve viscous, anti-oxidizing, anticorrosive and anti-erosive properties are considered as well. They are used within the temperature range from - 60оС to +125оС with overheats up to +150

  19. A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

    Linhui ZHAO; Xin FANG


    Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150℃ and 28MPa to overcome problems of traditional high-temperature plun-ger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90℃ phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mono-neuron self-adaptive PID control algorithm is also improved by modifying parameters K and η. Two improved controllers are used to control the two cylinders,respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.

  20. Hydraulic Soft Yaw System for Multi MW Wind Turbines

    Stubkier, Søren

    Horizontal axis wind turbines utilize a yaw system to keep the rotor plane of the wind turbine perpendicular to the main wind direction. If the wind direction changes, the wind turbine follows the direction change by yawing. If the wind turbine does not yaw, there will be a reduction in produced...... of nine concepts for hydraulic yaw systems and shown that the loading of the turbine structure may be damped if the yaw system is allowed to deflect under loading. An extensions of the open source wind turbine code FAST of a state of the art wind turbine including the yaw degree of freedom and friction...

  1. Application research on hydraulic coke cutting monitoring system based on optical fiber sensing technology

    Zhong, Dong; Tong, Xinglin


    With the development of the optical fiber sensing technology, the acoustic emission sensor has become one of the focal research topics. On the basis of studying the traditional hydraulic coke cutting monitoring system, the optical fiber acoustic emission sensor has been applied in the hydraulic coke cutting monitoring system for the first time, researching the monitoring signal of the optical fiber acoustic emission sensor in the system. The actual test results show that using the acoustic emission sensor in the hydraulic coke cutting monitoring system can get the real-time and accurate hydraulic coke cutting state and the effective realization of hydraulic coke cutting automatic monitoring in the Wuhan Branch of Sinopec.

  2. 槽式太阳能聚光器太阳跟踪液压驱动系统设计%The Design of Hydraulic Drive Control System For Parabolic Concentrator Sun-tracking Mechanism

    谢超; 罗馨茹; 俞竹青


    槽式太阳能热发电系统中,其聚光器太阳跟踪性能是太阳能采集率的重要影响因素.设计了一套槽式太阳能聚光器太阳跟踪机构专用的中高压液压驱动控制系统,并系统采用了比例溢流阀和比例流量阀,因此具有驱动力矩大、启动平稳、跟踪精度高的特点.实验证明了其设计的正确性和可靠性.%In solar parabolic trough thermal power (SPTTP) system, the parabolic concentrator sun— tracking performance has significant influence on solar collection rate. A set of special —purpose hydraulic drive control system is developed for sun—tracking mechanism of Parabolic Concentrator. It has the features of great driving force, stable starting and accurate positioning. Testing and the actual use have proved the correctness, feasibility and reliability of proposed design.

  3. MC90Y煤层气车载专用钻机液压控制系统%Research on the Hydraulic Control System for the Mcg0Y CBM Truck-mounted Rig

    纪友哲; 闵庆利; 王金宏


    To make a further improvement of the automation level of coal bed methane (CBM) drilling rig, reduce the driller operation to the minimum and improve the self-checking capacity of equipment, the MC90Y CBM truck-mounted drilling rig was developed. The rig adopts the electro-hydraulic control mode and centralized control of the PLC controller. The hiosting and rotating system uses the proportional volumetric pump for velocity regula- tion. The auxiliary system adopts the constant pressure variable displacement pump to supply power. The hoisting system adopts the balance valve loop design to achieve a smooth operation in positive load, negatiye load and varia- ble load. The handle orientation control is adopted to reduce the operating complexity of the driller. The operation of the hoisting and rotating system is optimized. The control system has the functions of self-check, monitoring and self-locking protection, improving the safety and protection capacity of the rig. The testing and the field application show that the drilling rig is simple in operation, desirable in control and smooth in operation.%为进一步提高煤层气钻机的自动化水平,尽量减少司钻的操作,提高设备自检能力,研制了MC90Y煤层气车载专用钻机。该钻机采用电液控制方式,PLC控制器集中控制,起升和旋转系统使用比例容积泵调速,辅助系统采用恒压变量泵提供动力;起升系统采用平衡阀回路设计,实现了正载荷、负载荷和变载荷情况下的平稳运行;采用手柄方位辨识控制,降低司钻的操作复杂性,优化起升和旋转系统的运行;控制系统具有自检、监测和自锁保护等功能,提高了钻机的安全保护能力。测试及现场应用结果表明,该钻机操作便捷,可控性好,运行平稳。

  4. Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems

    Clifton B. Higdon III


    Industrial manufacturing in the U.S. accounts for roughly one third of the 98 quadrillion Btu total energy consumption. Motor system losses amount to 1.3 quadrillion Btu, which represents the largest proportional loss of any end-use category, while pumps alone represent over 574 trillion BTU (TBTU) of energy loss each year. The efficiency of machines with moving components is a function of the amount of energy lost to heat because of friction between contacting surfaces. The friction between these interfaces also contributes to downtime and the loss of productivity through component wear and subsequent repair. The production of new replacement parts requires additional energy. Among efforts to reduce energy losses, wear-resistant, low-friction coatings on rotating and sliding components offer a promising approach that is fully compatible with existing equipment and processes. In addition to lubrication, one of the most desirable solutions is to apply a protective coating or surface treatment to rotating or sliding components to reduce their friction coefficients, thereby leading to reduced wear. Historically, a number of materials such as diamond-like carbon (DLC), titanium nitride (TiN), titanium aluminum nitride (TiAlN), and tungsten carbide (WC) have been examined as tribological coatings. The primary objective of this project was the development of a variety of thin film nanocoatings, derived from the AlMgB14 system, with a focus on reducing wear and friction in both industrial hydraulics and cutting tool applications. Proof-of-concept studies leading up to this project had shown that the constituent phases, AlMgB14 and TiB2, were capable of producing low-friction coatings by pulsed laser deposition. These coatings combine high hardness with a low friction coefficient, and were shown to substantially reduce wear in laboratory tribology tests. Selection of the two applications was based largely on the concept of improved mechanical interface efficiencies for

  5. Integrating a piezoelectric actuator with mechanical and hydraulic devices to control camless engines

    Mercorelli, Paolo; Werner, Nils


    The paper deals with some interdisciplinary aspects and problems concerning the actuation control which occur in the integration of a piezoelectric structure in an aggregate actuator consisting of a piezoelectric, a stroke ratio displacement, a mechanical and a hydraulic part. Problems like compensation of the piezo hysteresis effect, scaling force-position to obtain an adequate displacement of the actuator and finally the control of such a complex aggregate system are considered and solved. Even though this work considers a particular application, the solutions proposed in the paper are quite general. In fact, the considered technical aspects occurring in systems which utilize piezoelectric technologies can be used in a variegated gamma of actuators integrating piezoelectric technologies. A cascade controller is proposed to combine a Feedforward action with an internal and an external PI-Controller. The Feedforward Controller is based on the model of the whole actuator, so particular attention is paid to the model structure. The resulting Feedforward action is an adaptive one to compensate hydraulic pressure faults. Real measurements are shown.



    A new control scheme, the hybrid fuzzy control method, for active damping suspension system is presented. The scheme is the result of effective combination of the statistical optimal control method based on the statistical property of suspension system, with the bang-bang control method based on the real-time characteristics of suspension system. Computer simulations are performed to compare the effectiveness of hybrid fuzzy control scheme with that of optimal damping control, bang-bang control, and passive suspension. It takes the effects of time-variant factors into full account. The superiority of the proposed hybrid fuzzy control scheme for active damping suspension to the passive suspension is verified in the experiment study.

  7. The development of radiation hardened robot for nuclear facility - Development of embedded controller for hydraulic robot

    Kim, Byung Kook; Kim, Jae Kwon [Korea Advanced Institute of Science and Technology, Taejon (Korea)


    We designed and implemented a reliable hierarchical control system for hydraulic robots for nuclear power plant maintenance. In hazardous environments such as nuclear power plants, robot systems or automated equipment should be used instead of human being for maintenance and repair. Such robot should guarantee high reliability in hazardous environments such as high radiation or high temperature. The overall system is composed of three hierarchical subsystems: i) supervisory controller in safe zone for operator interaction with monitoring and commanding and graphic user interface, ii) master controller in semi-hazardous zone for control function, and iii) slave controller in hazardous zone for sensing and actuation. These subsystems are connected with suitable communication channels: a) master-slave communication channel implemented with CAN (Control Area Network) and b) supervisory-master communication with Ethernet. The master and the slave controllers construct a feedback closed-loop control system. In order to improve reliability, the slave controller is duplicated using cold-standby scheme, and master-slave communication channel is also duplicated. The overall system is implemented harmonically, and we obtained fast control interval of 1msec, which is sufficient for high-performance real-time control. 12 refs., 58 figs., 13 tabs. (Author)

  8. Design of A Hydraulic Power Take-off System for the Wave Energy Device with An Inverse Pendulum

    张大海; 李伟; 赵海涛; 鲍经纬; 林勇刚


    This paper describes a dual-stroke acting hydraulic power take-off (PTO) system employed in the wave energy converter (WEC) with an inverse pendulum. The hydraulic PTO converts slow irregular reciprocating wave motions to relatively smooth, fast rotation of an electrical generator. The design of the hydraulic PTO system and its control are critical to maximize the generated power. A time domain simulation study and the laboratory experiment of the full-scale beach test are presented. The results of the simulation and laboratory experiments including their comparison at full-scale are also presented, which have validated the rationality of the design and the reliability of some key components of the prototype of the WEC with an inverse pendulum with the dual-stroke acting hydraulic PTO system.

  9. Optimising root system hydraulic architectures for water uptake

    Meunier, Félicien; Couvreur, Valentin; Draye, Xavier; Javaux, Mathieu


    In this study we started from local hydraulic analysis of idealized root systems to develop a mathematical framework necessary for the understanding of global root systems behaviors. The underlying assumption of this study was that the plant is naturally optimised for the water uptake. The root system is thus a pipe network dedicated to the capture and transport of water. The main objective of the present research is to explain the fitness of major types of root architectures to their environment. In a first step, we developed links between local hydraulic properties and macroscopic parameters of (un)branched roots. The outcome of such an approach were functions of apparent conductance of entire root system and uptake distribution along the roots. We compared our development with some allometric scaling laws for the root water uptake: under the same simplifying assumptions we were able to obtain the same results and even to expand them to more physiological cases. Using empirical data of measured root conductance, we were also able to fit extremely well the data-set with this model. In a second stage we used generic architecture parameters and an existent root growth model to generate various types of root systems (from fibrous to tap). We combined both sides (hydraulic and architecture) then to maximize under a volume constraint either apparent conductance of root systems or the soil volume explored by active roots during the plant growth period. This approach has led to the sensitive parameters of the macroscopic parameters (conductance and location of the water uptake) of each single plant selected for this study. Scientific questions such as: "What is the optimal sowing density of a given hydraulic architecture ?" or "Which plant traits can we change to better explore the soil domain ?" can be also addressed with this approach: some potential applications are illustrated. The next (and ultimate phase) will be to validate our conclusions with real architectures

  10. The gravitational potential energy regeneration system with closed-circuit of boom of hydraulic excavator

    Chen, Mingdong; Zhao, Dingxuan


    Considering the disadvantage of higher throttling loss for the open-circuit hydrostatic transmission at present, a novel gravitational potential energy regeneration system (GPERS) of the boom of hydraulic excavator, namely the closed-circuit GPERS, is proposed in this paper. The closed-circuit GPERS is based on a closed-circuit hydrostatic transmission and adopts a hydraulic accumulator as main energy storage element fabricated in novel configuration to recover the entire gravitational potential energy of the boom of hydraulic excavator. The matching parameter and control system design are carried out for the proposed system, and the system is modeled based on its physical attributes. Simulation and experiments are performed to validate the employed mathematical models, and then, the velocity and the pressure performance of system are analyzed. It is observed that the closed-circuit GPERS shows better velocity control of the boom and response characteristics. After that, the average working efficiency of the closed-circuit GPERS of boom is estimated under different load conditions. The results indicate that the proposed system is highly effective and that the average working efficiency in different load conditions varied from 60% to 68.2% for the experiment platform.

  11. Identification and optimization for hydraulic roll gap control in strip rolling mill

    孙杰; 陈树宗; 韩欢欢; 陈兴华; 陈秋捷; 张殿华


    In order to improve the control performance of strip rolling mill, theoretical model of the hydraulic gap control (HGC) system was established. HGC system offline identification scheme was designed for a tandem cold strip mill, the system model parameters were identified by ARX model, and the identified model was verified. Taking the offline identified parameters as the initial values, online identification using recursive least square was carried out with model parameters changing. For the purpose of improving system robustness and decreasing the sensitivity due to model errors, the HGC system based on generalized predictive control (GPC) was designed, and simulation experiments for traditional controller and GPC controller were conducted. The results show that both controllers acquire good control effect with model matching. When the model mismatches, for the traditional controller, the overshot will increase to 76.7% and the rising time will increase to 165.7 ms, which cannot be accepted by HGC system; for the GPC controller, the overshot is less than 8.5%, and the rising time is less than 26 ms in any case.

  12. Method for use of hydraulically or electrically controlled solenoids under failed on conditions

    Bolenbaugh, Jonathan M.; Naqi, Syed


    A method to operate a clutch device in an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and at least one electric machine includes, in response to a failure condition detected within a flow control device configured to facilitate flow of hydraulic fluid for operating the clutch device, selectively preventing the flow of hydraulic fluid from entering the flow control device and feeding the clutch device. Synchronization of the clutch device is initiated when the clutch device is intended for activation, and only if the clutch device is synchronized, the flow of hydraulic fluid is selectively permitted to enter the flow control device to activate the clutch device.


    Han Yilun


    Fault diagnosis expert system for hydraulic support is studied.The system is achieved by Turbo-prolong Language, it summaries the experience of the domain expert and sets up a fault tree, knowledge base is developed by a productive rule.According to the feature of diagnosis, the system selects forward non-determination inferring and limited depth-first search strategy.It can accomplish expert diagnosis of more than 50 kinds faults in hydraulic support.

  14. Study on Knowledge -based Intelligent Fault Diagnosis of Hydraulic System

    Xuexia Liu


    Full Text Available A general framework of hydraulic fault diagnosis system was studied. It consisted of equipment knowledge bases, real-time databases, fusion reasoning module, knowledge acquisition module and so on. A tree-structure model of fault knowledge was established. Fault nodes knowledge was encapsulated by object-oriented technique. Complete knowledge bases were made including fault bases and diagnosis bases. It could describe the fault positions, the structure of fault, cause-symptom relationships, diagnosis principles and other knowledge. Taking the fault of left and right lifting oil cylinder out of sync for example, the diagnostic results show that the methods were effective.

  15. Hydraulic external pre-isolator system for LIGO

    Wen, S.; Mittleman, R.; Mason, K.; Giaime, J.; Abbott, R.; Kern, J; O'Reilly, B.; Bork, R.; Hammond, M.; Hardham, C.; Lantz, B.; W. Hua; Coyne, D.; Traylor, G.; Overmier, H.


    The hydraulic external pre-isolator (HEPI) is the first six degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGOʼs fifth science run, successfully cutting down the disturbance seen by LLOʼs suspended optics in the two most prominent seismic disturbance bands, the microseism (0.1–0.3 Hz) and the anthropogenic (1–3 Hz) bands, by a...

  16. Linear hydraulic drive system for a Stirling engine

    Walsh, Michael M.


    A hydraulic drive system operating from the periodic pressure wave produced by a Stirling engine along a first axis thereof and effecting transfer of power from the Stirling engine to a load apparatus therefor and wherein the movable, or working member of the load apparatus is reciprocatingly driven along an axis substantially at right angles to the first axis to achieve an arrangement of a Stirling engine and load apparatus assembly which is much shorter and the components of the load apparatus more readily accessible.

  17. Design and Study of the Hydraulic Control System for Mine Traction Locomotive%矿用牵引机车液压控制系统的设计与研究



    This paper analyzed the working principle of mine traction locomotive and designed the hydraulic control system for mine traction locomotive according to the long tunnel construction of traction locomotive requested. It ad-opted intelligent control algorithm of the RBF neural network self-tuning PID to adjust the displacement of variable pump and variable motor intelligently to make rotational speed output reach rotational speed given. It was modeled by applying co-simulation software of AMESim/simulink. The relevant parameters were been optimized. The dy-namic control co-simulation was accomplished. Through the co-simulation and experiments, the results show that it can accurately, quickly and stablely adjust rotational speed.%针对长大隧道施工对牵引机车的要求,分析了矿用牵引机车行走驱动的工作原理并设计了矿用牵引机车液压控制系统,该控制系统采用RBF神经网络自整定PID控制算法分别对变量泵和变量马达的排量智能调节,使输出转速达到给定的转速。运用AMESim/simulink液压联合仿真软件平台对矿用牵引机车液压控制系统进行建模,并对相关参数进行优化设计,实现了动态仿真。通过对其液压控制系统进行联合仿真和试验,结果表明,其能够准确、快速、平稳地对转速进行调节。

  18. 液压泵试验台系统设计%Research of Test System of Hydraulic Pump

    阳宝元; 黄志坚; 何曼


    One test system of hydraulic pump which includes hydraulic system, electronic control system and computer control system is de-signed, and some critical types of components are selected. The whole system is simple, practical which can reliably and quickly test perfor-mance parameters of hydraulic pump.%设计了一种液压泵试验台系统,包括液压系统、电控系统和计算机测控系统,对系统的相关元件进行了选型,整个系统简单实用,能可靠、快捷地对液压泵的性能参数进行测试。

  19. Super Twisting Second Order Sliding Mode Control for Position Tracking Control of Hydraulic Drives

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.;


    In this paper a control strategy based on second order sliding modes, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD), is proposed. The main target is to overcome problems with linear controllers deteriorating performance due to the strong...... nonlinearities characterizing VCD's. The proposed controller requires pressure-, valve- and piston position measurements, and is based on the so-called super twisting algorithm and compensation of controlgain nonlinearities. Simulation results demonstrate strong robustness when subjected to large perturbations...

  20. Hydraulic calculation of gravity transportation pipeline system for backfill slurry

    ZHANG Qin-li; HU Guan-yu; WANG Xin-min


    Taking cemented coal gangue pipeline transportation system in Suncun Coal Mine, Xinwen Mining Group, Shandong Province, China, as an example, the hydraulic calculation approaches and process about gravity pipeline transportation of backfill slurry were investigated. The results show that the backfill capability of the backfill system should be higher than 74.4m3/h according to the mining production and backfill times in the mine; the minimum velocity (critical velocity) and practical working velocity of the backfill slurry are 1.44 and 3.82m/s, respectively. Various formulae give the maximum ratio of total length to vertical height of pipeline (L/H ratio) of the backfill system of 5.4, and then the reliability and capability of the system can be evaluated.



    An effective controller and compensator is designed by using the system identification and constant structure theory to realize the effective control. The experimental results indicate the extraneous torque can be decreased by 90% and the characteristics can be improved greatly by means of this kind of method.


    Wang Qingfeng; Li Yanmin; Zhong Tianyu; Xu Guohua


    Based on the analysis of the-state-of-the-art of pressure compensation of underwater hydraulic systems (UHSs), a new method of pressure compensation of UHSs, whose hydraulic power unit is in the atmospheric circumstance, is proposed. And a pilot-operated relief valve with pressure compensation is realized. The pressure compensation precision is guaranteed by direct detection. Its dynamic performance and stability are improved by a dynamic feedback. Theoretical study, simulation and experiment show that the pilot-operated relief valve with pressure compensation has a fine property of tracking underwater ambient pressure and meet the requirement of underwater ambient pressure compensation.

  3. Imaging hydraulic fractures by microseismic migration for downhole monitoring system

    Lin, Ye; Zhang, Haijiang


    It has been a challenge to accurately characterize fracture zones created by hydraulic fracturing from microseismic event locations. This is because generally detected events are not complete due to the associated low signal to noise ratio and some fracturing stages may not produce microseismic events even if fractures are well developed. As a result, spatial distribution of microseismic events may not well represent fractured zones by hydraulic fracturing. Here, we propose a new way to characterize the fractured zones by reverse time migration (RTM) of microseismic waveforms from some events. This is based on the fact that fractures filled with proppants and other fluids can act as strong scatterers for seismic waves. Therefore, for multi-stage hydraulic fracturing, recorded waveforms from microseismic events induced in a more recent stage may be scattered by fractured zones from previous stages. Through RTM of microseismic waveforms in the current stage, we can determine fractured zones created in previous stages by imaging area of strong scattering. We test the feasibility of this method using synthetic models with different configurations of microseismic event locations and borehole sensor positions for a 2D downhole microseismic monitoring system. Synthetic tests show that with a few events fractured zones can be directly imaged and thus the stimulated reservoir volume (SRV) can be estimated. Compared to the conventional location-based SRV estimation method, the proposed new method does not depend on the completeness of detected events and only a limited number of detected and located events are necessary for characterizing fracture distribution. For simplicity, the 2D model is used for illustrating the concept of microseismic RTM for imaging the fracture zone but the method can be adapted to real cases in the future.

  4. Effects of shifting time on pressure impact in hydraulic systems

    ZHU Zhen-cai; CHEN Guo-an


    The limitations in existing measures for absorbing pressure impact in hydraulic systems were summarized in this paper. Based on the forming principle of the oil in a hydrostatic closed pressure chamber, the underlying reasons of the pressure impact were analyzed theoretically, the intrinsic laws that the extent of the pressure impact in hydraulic oil lines are affected by some factors, such as oil elastic modulus, oil line's geometrical volume, and changing rate of oil volume versus time etc, were discussed. Experimental investigations into pressure impact in all pressure chambers because of shifting were conducted under different working conditions by employing a special experimental system. The effects of shifting time on pressure impact were studied. A new concept with universal meaning, i.e. optimal shifting time, and its characterizing parameter and the methods of shifting at optimal shifting time were also proposed. The results show that shifting time lag △t is of rationality and maneuverablility. The higher the working pressure, the shorter the shifting time.

  5. Debris Control at Hydraulic Structures in Selected Areas of the United States and Europe


    Selected Areas of the United States and Europe by N. Wallerstein , C. R. Thome, University of Nottingham S. R. Abt, Colorado State University Approved...December 1997 Debris Control at Hydraulic Structures in Selected Areas of the United States and Europe by N. Wallerstein , C. R. Thome Department... Wallerstein , N. Debris control at hydraulic structures in selected areas of the United States and Europe / by N. Wallerstein , C.R. Thome, S.R. Abt



    Modeling and digital simulation is an effective method to analyze the dynamic characteristics of hydraulic system. It is difficult to determine some performance parameters in the hydraulic system by means of currently used modeling methods. The "gray-box" modeling method for large-scale hydraulic system is introduced. The principle of the method, the submodels of some components and the parameters identification of components or subsystem are researched.

  7. The study on measures to improve the reliability of the hydraulic systems of shearers

    YUAN Hui; XU Long-jiang; TIAN Da-biao; ZHAO Yan-ling


    The authors indicate that the failure of hydraulic systems of shearers can drop greatly, its' reliability and service life can be increased by the use of a field oil contamination analyser and filter device to control the oil cont amination of the hydraulic systems of shearers. Experimental provement of siltin g-theory contamination analyser are carried out.The filter effect of portable h ydraulic driving oil-filter model YLJ-21 is examinationed in laboratory and fi e ld experiment. From January to August 1992, on-site experimental research using a silting-theory contamination analyser and oil-filter model YLJ-21 to contr o l the oil contamination was carried out in the Datong Coal Mining Bureau.

  8. From the Kinetic Energy Recovery System to the Thermo-Hydraulic Hybrid Motor Vehicle

    Cristescu, Corneliu; Drumea, Petrin; Guta, Dragos; Dumitrescu, Catalin


    The paper presents some theoretical and experimental results obtained by the Hydraulics and Pneumatics Research Institute INOE 2000-IHP with its partners, regarding the creating of one hydraulic system able to recovering the kinetic energy of the motor vehicles, in the braking phases, and use this recovered energy in the starting and accelerating phases. Also, in the article is presented a testing stand, which was especially designed for testing the hydraulic system for recovery the kinetic energy. Through mounting of the kinetic energy recovering hydraulic system, on one motor vehicle, this vehicle became a thermo-hydraulic hybrid vehicle. Therefore, the dynamic behavior was analyzed for the whole hybrid motor vehicle, which includes the energy recovery system. The theoretical and experimental results demonstrate the possible performances of the hybrid vehicle and that the kinetic energy recovery hydraulic systems are good means to increase energy efficiency of the road motor vehicles and to decrease of the fuel consumption.

  9. Electrical analysis and design of long-distance subsea production electro-hydraulic control systems%长距离水下生产复合电液控制系统电力分析与设计

    胡意茹; 魏澈; 李强; 刘国锋; 张昊; 洪毅


    As the tieback distance gets longer,subsea production control system is facing the new challenge of low-voltage power transmission over long distance.Based on the two-port network and uniform trans-mission line theory,a dynamic simulation model for both single-phase AC and DC electricity of subsea elec-tro-hydraulic control systems were developed using Matlab/Simulink.The correctness of the proposed model has been verified by comparing the results of the model with that of existing WC 9-2/9-3/10-3 elec-trical analysis report and traditional reverse deduction method,thus making up the defect of SimulationX's subsea electrical library which can only be used to conduct AC electrical analysis.Schemes for single phase AC and DC power supply have been proposed,and the pros and cons,as well as the scope of application of the two power supply modes have been illustrated.The systematic electrical modeling approach and design procedures for subsea production control systems established herein have essential reference significance for upcoming similar projects.%随着回接距离增加,水下生产控制系统面临着低压长距离输电的新挑战.根据二端口网络和均匀传输线理论,建立了基于Matlab/Simulink的长距离水下生产复合电液控制系统单相交流和直流电力仿真模型.通过与文昌9-2/9-3/10-3项目电力分析报告和倒推法计算结果对比,验证了本文模型的正确性,弥补了SimulationX水下电力库只能进行单相交流仿真的缺陷.应用本文仿真模型得到了单相交流和直流2种不同供电方式下的建议设计方案,对比了单相交流和直流2种供电方式的优缺点及适用范围.本文所形成的水下生产控制系统电力分析建模方法和设计流程,对我国后续类似工程项目具有一定的借鉴意义.

  10. Thermal Hydraulic Analysis on Containment Filtered Venting System

    Bang, Young Suk; Park, Tong Kyu; Lee, Doo Yong; Lee, Byung Chul [FNC Technology Co. Ltd., Yongin (Korea, Republic of); Lee, Sang Won; Kim, Hyeong Taek [KHNP-Central Research Institute, Daejeon (Korea, Republic of)


    In this study, the thermal hydraulic conditions (e. g. pressure and flow rate) at each component have been examined and the sensitivity analysis on CFVS design parameters (e. g. water inventory, volumetric flow rate). The purpose is to know the possible range of flow conditions at each component to determine the optimum size of filtration system. GOTHIC code has been used to simulate the thermal-hydraulic behavior inside of CFVS. The behavior of flows in the CFVS has been investigated. The vessel water level and the flow rates during the CFVS operation are examined. It was observed that the vessel water level would be changed significantly due to steam condensation/thermal expansion and steam evaporation. Therefore, the vessel size and the initial water inventory should be carefully determined to keep the minimum water level required for filtration components and not to flood the components in the upper side of the vessel. It has been also observed that the volumetric flow rate is maintained during the CFVS operation, which is beneficial for pool scrubbing units. However, regarding the significant variations at the orifice downstream, careful design would be necessary.

  11. Experimental validation of microseismic emissions from a controlled hydraulic fracture in a synthetic layered medium

    Roundtree, Russell

    A controlled hydraulic fracture experiment was performed on two medium sized (11" x 11" x 15") synthetic layered blocks of low permeability, low porosity Lyons sandstone sandwiched between cement. The purpose of the research was to better understand and characterize the fracture evolution as the fracture tip impinged upon the layer boundaries between the well bonded layers. It is also one of the first documented uses of passive microseismic used in a laboratory environment to characterize hydraulic fracturing. A relatively low viscosity fluid of 1000 centipoise, compared to properly scaled previous work (Casas 2005, and Athavale 2007), was pumped at a constant rate of 10 mL/minute through a steel cased hole landed and isolated in the sandstone layer. Efforts were made to contain the hydraulic fracture within the confines of the rock specimen to retain the created hydraulic fracture geometry. Two identical samples and treatment schedules were created and differed only in the monitoring system used to characterize the microseismic activity during the fracture treatment. The first block had eight embedded P-wave transducers placed in the sandstone layer to record the passive microseismic emissions and localize the location and time of the acoustic event. The second block had six compressional wave transducers and twelve shear wave transducers embedded in the sandstone layer of the block. The intention was to record and process the seismic data using conventional P-wave to S-wave difference timing techniques well known in industry. While this goal ultimately not possible due to the geometry of the receiver placements and the limitations of the Vallene acquisition processing software, the data received and the events localized from the 18 transducer test were of much higher numbers and quality than on the eight transducer test. This experiment proved conclusively that passive seismic emission recording can yield positive results in the laboratory. Just as in the field

  12. A Target Tracking System for Applications in Hydraulic Engineering

    SHEN Qiaonan; AN Xuehui


    A new type of digital video monitoring system (DVMS) named user defined target tracking system (UDTTS), was developed based on the digital image processing (DIP) technology and the practice demands of construction site management in hydraulic engineering. The position, speed, and track of moving targets such as humans and vehicles, which could be calculated by their locations at anytime in images basically, were required for management. The proposed algorithm, dependent on the context-sensitive moving infor- mation of image sequences which was much more than one or two images provided, compared the blobs' properties in current frame to the trajectories of targets in the previous frames and then corresponded them. The processing frame rate is about 10fps with the image 240-by-120 pixels. Experimental results show that position, direction, and speed measurements have an accuracy level compatible with the manual work. The user-define process makes the UDTTS available to the public whenever appropriate.

  13. Variants of Secondary Control with Power Recovery for Loading Hydraulic Driving Device

    QI Xiaoye


    Current high power load simulators are generally incapable of obtalning both high loading performance and high energy efficiency. Simulators with high energy efficiency are used to simulate static-state load, and those with high dynamic performance typically have low energy efficiency. In this paper, the variants of secondary control (VSC) with power recovery are developed to solve this problem for loading hydraulic driving devices that operate under variable pressure, unlike classical secondary control (CSC) that operates in constant pressure network. Hydrostatic secondary control units are used as the loading components, by which the absorbed mechanical power from the tested device is converted into hydraulic power and then fed back into the tested system through 4 types of feedback passages (FPs). The loading subsystem can operate in constant pressure network, controlled variable pressure network, or the same variable pressure network as that of the tested device by using different FPs. The 4 types of systems are defined, and their key techniques are analyzed, including work principle, simulating the work state of original tested device, static operation points, loading performance, energy efficiency, and control strategy, etc. The important technical merits of the 4 schemes are compared, and 3 of the schemes are selected, designed, simulated using AMESim and evaluated. The researching results show that the investigated systems can simulate the given loads effectively, realize the work conditions of the tested device, and furthermore attaln a high power recovery efficiency that ranges from 0.54 to 0.85, even though the 3 schemes have different loading performances and energy efficiencies. This paper proposes several loading schemes that can achieve both high dynamic performance and high power recovery efficiency.

  14. Research on the closure law of hydraulic control slow closing butterfly valve in pressure flow water diversion system%压力流输水系统中缓闭式液控蝶阀关闭规律研究

    刘奕朗; 高学平; 蒋琳琳


    Water diversion system of long - distance and high - lift pressure flow will produce serious damage once pump - stopping water hammer takes place. It is a simple and effective water hammer protection measure to set one hydraulic control slow closing butterfly valve at the outlet of pump with appropriate closure way. The thesis, combining practical engineering, solve the water hammer basic equations by the method of characteristics, compare the results of different valve closure way, including the envelope line of piezometric head, pressure change at outlet of pump station and rotate speed change, then proposes the appropriate way of valve closure. The results can provide a reference for the setting of pump - stopping water hammer protective measures.%对于长距离、高扬程压力流输水系统,一旦发生停泵水锤,将对输水系统产生严重危害.在泵出口设置缓闭式液控蝶阀并以适当的方式关阀是一种简单有效的水锤防护措施.本文结合实际工程,通过特征线法求解水锤基本方程,比较不同关阀方式下管路沿程压力变化、泵站出口断面压力变化及水泵转速变化,提出合适的关阀方式.研究成果可为停泵水锤防护措施的设置提供参考.

  15. Application of optical fiber sensing technology in the hydraulic decoking monitoring system

    Fan, Yun-feng; Tong, Xing-lin; Ji, Tao; Gao, Xue-qing; Zhong, Dong


    On the basis of the analysis of the current hydraulic decoking monitoring system, it is proposed that use optical fiber Bragg grating (FBG) vibration sensor and fiber Fabry-Perot (FP) acoustic sensors to online monitor vibration signal and audio signal hydraulic of the coke drum in the running state progress, analysis the vibration sensor and acoustic sensor used in the system. Based on the actual monitoring results in Sinopec Wuhan Branch , the fiber optic acoustic emission sensors is more suitable for the hydraulic decoking online monitoring system than the FBG vibration sensor ,which can more accurate monitor of hydraulic decoking.

  16. Output Feedback Control of Electro-Hydraulic Cylinder Drives using the Twisting Algorithm

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.


    This paper discusses the utilization of the so-called twisting algorithm when applied in output feedback position control schemes for electro-hydraulic cylinder drives. The twisting controller was the first second order sliding controller ever introduced, and can structure-wise be considered...... contributions in literature. This paper considers the twisting algorithm when applied directly for output feedback control, and with the design based on a reduced order model representation of an arbitrary valve driven hydraulic cylinder drive. The consequence of implementing such a controller with the well...

  17. A Frequency Response Approach to Sliding Control Design for Hydraulic Drives

    Schmidt, Lasse; Johansen, Per; Andersen, Torben Ole


    , the application of so-called boundary layers are commonly applied, guaranteeing sliding precision in some well-defined vicinity of the control target. Commonly the control target, or sliding manifold, is designed as some desired closed loop dynamics of the controlled plant, utilizing multiple states as feedback....... However, when considering hydraulic cylinder drives, such full state feedback may not be available, and alternative approaches to conventional methods may be considered. This issue is addressed in this paper in regard to tracking control design for valve controlled hydraulic cylinder drives, and a design...

  18. Field investigation on consumer behavior and hydraulic performance of a district heating system in Tianjin, China

    Xu, Baoping; Fu, Lin; Di, Hongfa [Department of Building Science, Tsinghua University, Beijing 100084 (China)


    With the implementation of heat reforms in China, the application of thermostatic radiator valves (TRVs) has been gaining popularity in the new-style district heating systems (DHSs). The objective of this study was to investigate consumer behavior (including regulation of TRVs and opening of windows) and its influences on the hydraulic performance and energy consumption of individuals and the whole system. The concurrence rate of individual behaviors and hydraulic interactions between individuals were analyzed. This study should be helpful to gain a comprehensive understanding of the new DHSs in China and consider a proper design/control strategy for these systems. Questionnaires and field observations of consumer behavior, tests of hydraulic performance, and surveys of energy consumption were carried out in a DHS in Tianjin, which was one of the heat metering and billing demonstration projects in China. The main results of the tests were as follows: water flow performance in apartment-level heating systems were diverse because consumers' behavior was varied and unpredictable, and the hydraulic interaction between consumers living along the line of a vertical pipe was obvious, and was stronger for terminal consumers with their TRVs set to higher values; however, flow variations in the whole DHS, which included 910 households, were relatively constant. A probability analysis was carried out to explain this phenomenon, and the conclusion was drawn that when there were more than 200 consumers, the stochastic consumer regulation behavior would bring less than 10% of total flow variations. Finally, the power consumption of the circulation pump, heat consumption and energy-saving potential of this type of DHS were discussed and some suggestions for TRV regulation and pump operation were made. (author)

  19. ITHNA.SYS: An Integrated Thermal Hydraulic and Neutronic Analyzer SYStem for NUR research reactor

    Mazidi, S., E-mail: [Division Physique et Applications Nucléaires, Centre de Recherche Nucléaire de Draria (CRND), BP 43 Sebala, Draria, Alger (Algeria); Meftah, B., E-mail: [Division Physique et Applications Nucléaires, Centre de Recherche Nucléaire de Draria (CRND), BP 43 Sebala, Draria, Alger (Algeria); Belgaid, M., E-mail: [Faculté de Physique, Université Houari Boumediene, USTHB, BP 31, Bab Ezzouar, Alger (Algeria); Letaim, F., E-mail: [Faculté des Sciences et Technologies, Université d’El-oued, PO Box 789, El-oued (Algeria); Halilou, A., E-mail: [Division Réacteur NUR, Centre de Recherche Nucléaire de Draria, BP 43 Sebala, Draria, Alger (Algeria)


    Highlights: • We develop a neutronic and thermal hydraulic MTR reactor analyzer. • The analyzer allows a rapid determination of the reactor core parameters. • Some NUR reactor parameters have been analyzed. - Abstract: This paper introduces the Integrated Thermal Hydraulic and Neutronic Analyzer SYStem (ITHNA.SYS) that has been developed for the Algerian research reactor NUR. It is used both as an operating aid tool and as a core physics engineering analysis tool. The system embeds three modules of the MTR-PC software package developed by INVAP SE: the cell calculation code WIMSD, the core calculation code CITVAP and the program TERMIC for thermal hydraulic analysis of a material testing reactor (MTR) core in forced convection. ITHNA.SYS operates both in on-line and off-line modes. In the on-line mode, the system is linked, via the computer parallel port, to the data acquisition console of the reactor control room and allows a real time monitoring of major physical and safety parameters of the NUR core. PC-based ITHNA.SYS provides a viable and convenient way of using an accumulated and often complex reactor physics stock of knowledge and frees the user from the intricacy of adequate reactor core modeling. This guaranties an accurate, though rapid, determination of a variety of neutronic and thermal hydraulic parameters of importance for the operation and safety analysis of the NUR research reactor. Instead of the several hours usually required, the processing time for the determination of such parameters is now reduced to few seconds. Validation of the system was performed with respect to experimental measurements and to calculations using reference codes. ITHNA.SYS can be easily adapted to accommodate other kinds of MTR reactors.

  20. 直剪仪多级液压加载系统的设计与控制%Design and Control of Multilevel Loadings Hydraulic System of Direct Shear Apparatus

    吕原君; 杜时贵; 罗战友; 黄曼


    岩石材料不同形状接触面的静动力学特性是岩石力学研究重点。接触面力学特性研究的一个基本途径是通过接触面基本力学特性试验。为了得到稳定的岩体结构面抗剪强度,需要对不同尺寸的岩体结构面试样进行抗剪强度直剪试验。以现有直剪仪为基础,提出新设备的液压系统和控制方案,并对直剪仪法向力和剪切力的控制精度和方法等问题进行了分析。试验测试表明:该试验仪的测试结果可信,精度能满足工程设计要求。文中的研究为岩石试验提供了大压力范围、柔性控制的仪器设备,为测试试样的剪胀和尺寸效应提供装备。%The key research of rock mechanics is static or dynamic behavior between rock materials with various shapes of contact surface.The basic approach of the contact surface mechanics property research is through the contact surface basic mechanics property test.To get steady shear strength of rock joints,shear strength of different size of samples need be tested.Hydraulic system and control scheme of a new device were introduced based on existent direct shear apparatus.At the same time,control accuracy and methods of normal force and shear force were analyzed.The accuracy was validated by several laboratory and in-situ experiments.It meets engi-neering design demand.The research provides large pressure range and flexible control apparatus in testing stress-dilation and size effect of sample.

  1. 49 CFR 570.57 - Air brake system and air-over-hydraulic brake subsystem.


    ... 49 Transportation 6 2010-10-01 2010-10-01 false Air brake system and air-over-hydraulic brake... STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.57 Air brake system and air-over-hydraulic brake subsystem. The following requirements apply to vehicles with air brake and...

  2. 电动可调式动态流量平衡阀和末端电动调节定压差阀结合的水力平衡与控制策略%Hydraulic balance and control strategy of combination control system of electric adjustable dynamic balancing valve and terminal electric constant pressure valve

    孙晋飞; 郭健翔; 沈聪; 李林


    分析了集中空调系统水力失调的原因和解决措施,通过比较末端恒压差控制系统和应用电动可调式动态流量平衡阀的控制系统的控制原理以及变流量条件下的能耗高低,研究了这两个控制系统对管网中调节阀流量特性曲线的影响,具体分析了设备效率对系统性能的影响.%Examines the cause and solutions of hydraulic disorder of central air conditioning systems. According to the comparison of control principle and energy consumption under variable flow rate condition between the end constant pressure difference control system and the control system with electric adjustable dynamic balancing valve, studies the influence of the two control systems on the flow characteristic curve of the electric control valve, and analyses the influence of equipment efficiency on the performance of the system in detail.

  3. Tap Water Hydraulic Systems for Medium Power Applications

    Conrad, Finn; Adelstorp, Anders


    Presentation of new range of developed tap water hydraulic componets and applications for medium power up to 4 kW and 50 bar.......Presentation of new range of developed tap water hydraulic componets and applications for medium power up to 4 kW and 50 bar....

  4. Hydraulic Systems with Tap Water versus Bio-oils

    Conrad, Finn


    Deals with the advantages of using pure tap water hydraulics versus bio-oils for suiteable applications. Focus is in particular on food processing industry.......Deals with the advantages of using pure tap water hydraulics versus bio-oils for suiteable applications. Focus is in particular on food processing industry....

  5. Research on the rationality of transmission system for fast forging hydraulic press%快锻液压机传动系统合理性的探讨

    陈超; 范淑琴; 赵升吨; 崔敏超; 韩晓兰


    The research status of fast forging hydraulic press at home and abroad was introduced, and deficiencies of the fast forging press in the domestic development were pointed out. The structures and principles of valve controlled hydraulic transmission system, pump con-trolled hydraulic transmission system and servo hydraulic transmission system were analyzed, and the advantages and disadvantages of these three kinds of hydraulic transmission system were pointed out on the above basis. Compared with valve controlled hydraulic transmis-sion system and pump controlled hydraulic transmission system, servo hydraulic transmission system has the advantages of good servo per-formance, low cost, high processing quality and precision. Servo hydraulic transmission system is very suitable for fast forging hydraulic press. Finally, the characteristics of three different hydraulic transmission systems were summarized, and servo hydraulic transmission sys-tem was regarded as the main trend of development in fast forging hydraulic drive system.%首先介绍了快锻液压机的国内外研究现状,指出了国内快锻液压机发展的不足。又分别分析了阀控液压传动系统、泵控液压传动系统和伺服液压传动系统的结构和原理,并以此为基础指出了3种液压传动系统的优缺点。相比于阀控液压传动系统和泵控液压传动系统,伺服液压传动系统具有伺服性能好、成本低、加工质量和精度高等优点。伺服液压系统非常适合应用于快锻液压机。最后总结了3种不同的液压传动系统的特点,指出伺服液压传动系统将成为快锻液压机传动系统的主要发展趋势。

  6. Experimental-based Modelling and Simulation of Water Hydraulic Mechatronics Test Facilities for Motion Control and Operation in Environmental Sensitive Applications` Areas

    Conrad, Finn; Pobedza, J.; Sobczyk, A.


    proportional valves and servo actuators for motion control and power transmission undertaken in co-operation by Technical University, DTU and Cracow University of Technology, CUT. The results of this research co-operation include engineering design and test of simulation models compared with two mechatronic......The paper presents experimental-based modelling, simulation, analysis and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. The contributions includes results from on-going research projects on fluid power and mechatronics based on tap water hydraulic...... test rig facilities powered by environmental friendly water hydraulic servo actuator system. Test rigs with measurement and data acquisition system were designed and build up with tap water hydraulic components of the Danfoss Nessie® product family. This paper presents selected experimental...

  7. Borehole Heat Exchanger Systems: Hydraulic Conductivity and Frost-Resistance of Backfill Materials

    Anbergen, Hauke; Sass, Ingo


    constant radial stress boundary conditions (sigma 2 = sigma 3 = constant) • radial freezing from inside out, following the in-situ freezing direction The results differ substantially from prior test procedures (such as standardized frost tests for concrete or soft soils). Concentric frost-induced cracking was observed. The cracking pattern is in good agreement with cryostatic suction processes and frost heave in fine grained soils. The hydraulic conductivity of the system depends on the composition of the grout. With the developed testing device (and procedure) a unified and independent assessment and quality control becomes feasible. Adequate materials for advanced shallow geothermal systems can be clearly identified.

  8. Stabilizing Gap of Pole Electric Arc Furnace Using Smart Hydraulic System

    Maher Yahya Sallom


    Full Text Available Electric arc furnace applications in industry are related to position system of its pole, up and down of pole. The pole should be set the certain gap. These setting are needed to calibrate. It is done manually. In this research will proposed smart hydraulic to make this pole works as intelligent using proportional directional control valve. The output of this research will develop and improve the working of the electric arc furnace. This research requires study and design of the system to achieve the purpose and representation using Automation Studio software (AS, in addition to mathematically analyzed and where they were building a laboratory device similar to the design and conduct experiments to study the system in practice and compared with simulation.Experimental tests show that the performance of electro hydraulic closed loop system (EHCLS for position control is good and the output results are good and acceptable. The practical results and simulation using (AS software are clearly convergence. It was concluded that the possibility of the implementation of this project in industrial processes such as electric arc furnaces to control the distance between the pole and smelting molten material in addition to other applications.

  9. Analysis of load transfer stability control strategy in hydraulic synchronized continuous slippage

    LIU Yan-bo; WU Jian-zhong; ZHANG Xuan


    Hydraulic synchronized continuous slippage technique,which integrates mechanical,electrical and hydraulic control,is introduced in this paper for the practical requirements of some construction projects.The core of this technique (the stability of the load transfer) is illustrated in detail.Three speed control strategies to transfer the load-excessive,lower and same speed-are presented to accomplish the smoothness and stability in the process of slippage.An optimization of the speed control strategy (same speed) is deduced from the modeling analysis and its validity and maneuverability are tested by practical application,which provides evidence for similar engineering in theory and practice.

  10. Development of an Advanced Hydraulic Fracture Mapping System

    Norm Warpinski; Steve Wolhart; Larry Griffin; Eric Davis


    The project to develop an advanced hydraulic fracture mapping system consisted of both hardware and analysis components in an effort to build, field, and analyze combined data from tiltmeter and microseismic arrays. The hardware sections of the project included: (1) the building of new tiltmeter housings with feedthroughs for use in conjunction with a microseismic array, (2) the development of a means to use separate telemetry systems for the tilt and microseismic arrays, and (3) the selection and fabrication of an accelerometer sensor system to improve signal-to-noise ratios. The analysis sections of the project included a joint inversion for analysis and interpretation of combined tiltmeter and microseismic data and improved methods for extracting slippage planes and other reservoir information from the microseisms. In addition, testing was performed at various steps in the process to assess the data quality and problems/issues that arose during various parts of the project. A prototype array was successfully tested and a full array is now being fabricated for industrial use.

  11. Apu/hydraulic/actuator Subsystem Computer Simulation. Space Shuttle Engineering and Operation Support, Engineering Systems Analysis. [for the space shuttle


    Major developments are examined which have taken place to date in the analysis of the power and energy demands on the APU/Hydraulic/Actuator Subsystem for space shuttle during the entry-to-touchdown (not including rollout) flight regime. These developments are given in the form of two subroutines which were written for use with the Space Shuttle Functional Simulator. The first subroutine calculates the power and energy demand on each of the three hydraulic systems due to control surface (inboard/outboard elevons, rudder, speedbrake, and body flap) activity. The second subroutine incorporates the R. I. priority rate limiting logic which limits control surface deflection rates as a function of the number of failed hydraulic. Typical results of this analysis are included, and listings of the subroutines are presented in appendicies.

  12. Developing a Tool Point Control Scheme for a Hydraulic Crane Using Interactive Real-time Dynamic Simulation

    Mikkel M. Pedersen


    Full Text Available This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme is developed for the specific crane, considering the saturation phenomena of the system and practical implementation.

  13. Lead Coolant Test Facility Systems Design, Thermal Hydraulic Analysis and Cost Estimate

    Soli Khericha; Edwin Harvego; John Svoboda; Ryan Dalling


    The Idaho National Laboratory prepared a preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed: (1) Develop and Demonstrate Feasibility of Submerged Heat Exchanger; (2) Develop and Demonstrate Open-lattice Flow in Electrically Heated Core; (3) Develop and Demonstrate Chemistry Control; (4) Demonstrate Safe Operation; and (5) Provision for Future Testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimate. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

  14. Lead coolant test facility systems design, thermal hydraulic analysis and cost estimate

    Khericha, Soli, E-mail: [Battelle Energy Alliance, LLC, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Harvego, Edwin; Svoboda, John; Evans, Robert [Battelle Energy Alliance, LLC, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Dalling, Ryan [ExxonMobil Gas and Power Marketing, Houston, TX 77069 (United States)


    The Idaho National Laboratory prepared a preliminary technical and functional requirements (T and FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed below: Bullet Develop and demonstrate feasibility of submerged heat exchanger. Bullet Develop and demonstrate open-lattice flow in electrically heated core. Bullet Develop and demonstrate chemistry control. Bullet Demonstrate safe operation. Bullet Provision for future testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimated. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 Degree-Sign C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

  15. Robust Control for Static Loading of Electro-hydraulic Load Simulator with Friction Compensation

    YAO Jianyong; JIAO Zongxia; YAO Bin


    Load simulator is a key test equipment for aircraft actuation systems in hardware-in-the-loop-simulation.Static loading is an essential function of the load simulator and widely used in the static/dynamic stiffness test of aircraft actuation systems.The tracking performance of the static loading is studied in this paper.Firstly,the nonlinear mathematical models of the hydraulic load simulator are derived,and the feedback linearization method is employed to construct a feed-forward controller to improve the force tracking performance.Considering the effect of the friction,a LuGre model based friction compensation is synthesized,in which the unmeasurable state is estimated by a dual state observer via a controlled learning mechanism to guarantee that the estimation is bounded.The modeling errors are attenuated by a well-designed robust controller with a control accuracy measured by a design parameter.Employing the dual state observer is to capture the different effects of the unmeasured state and hence can improve the friction compensation accuracy.The tracking performance is summarized by a derived theorem.Experimental results are also obtained to verify the high performance nature of the proposed control strategy.

  16. Evidence for internal hydraulic control in the northern Øresund

    Nielsen, Morten Holtegaard


    are a contraction in the northern Oslashresund and the shallow Drogden sill at the entrance to the Baltic. The observations show that the two-layer flows through the contraction are often hydraulically controlled. The observations also reveal details of the transition from subcritical to supercritical flow....... In terms of the composite Froude number, on the basis of local flow parameters these details are that the flow may be subcritical as well as supercritical in different areas of some cross section. Existing theories on rotating hydraulics are unable to account for these circumstances, which are due...... to the strong influence of the Earth's rotation and the curvature of the streamlines. In the present study it is not attempted to explain these conditions, but the probable effects of rotation and curvature on the controlled flow rate are discussed briefly. Also, the possible effects of hydraulic control...

  17. Analysis of Dither in PWM Control on Electro-hydraulic Proportional Valve

    Guoping LIU


    Full Text Available Plus with modulation (PWM is widely used in proporational control systems for it is efficient, flexible and anti-interference. Due to the friction and hysteresis of electromagnet, hysteresis exists when hydraulic valve in steady-state, and hysteresis influences the dynamic characteristics of the valve seriously,the hysteresis can be improved by superimposing dithers with certain frequency and amplitude to the valve coil. Aiming at the character of anti-unloading power driver circuit ,this paper analyzed the parasitic dither which exists in ±24V PWM control,besides,the experiment shows that in a high frequency PWM, dither with independent frequency and amplitude can be generated by changing the frequency of the PWM, in this way, the dithers  and average current of coil  can be adjusted separately by changing PWM frequency and PWM duty cycle.  

  18. Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control

    F. Reventós


    Full Text Available Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV. ANAV is the consortium that runs the Ascó power plants (2 units and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC thermal-hydraulic analysis team has jointly worked together with ANAV engineers at different levels in the analysis and improvement of these reactors. This article is an illustration of the usefulness of computational analysis for operational support. The contents presented were operational between 1985 and 2001 and subsequently changed slightly following various organizational adjustments. The paper has two different parts. In the first part, it describes the specific aspects of thermal-hydraulic analysis tasks related to operation and control and, in the second part, it briefly presents the results of three examples of analyses that were performed. All the presented examples are related to actual situations in which the scenarios were studied by analysts using thermal-hydraulic codes and prepared nodalizations. The paper also includes a qualitative evaluation of the benefits obtained by ANAV through thermal-hydraulic analyses aimed at supporting operation and plant control.

  19. Active control system for high speed windmills

    Avery, D.E.


    A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed. 4 figs.

  20. Heat exchange and hydraulic resistance of compact laser mirror cooling systems

    Shanin, Yu. I.; Shanin, O. I.


    The hydraulic resistance of cooling systems for laser mirrors and the heat exchange in them have been investigated experimentally. The data obtained have been generalized for several cooling systems with different porous elements.

  1. Design and Simulation of Hydraulic System of Press Machine%压力机液压系统的设计与仿真

    宋晓美; 韩亮


    For the problems of the vibration and noise common to hydraulic system of press,the hydraulic and control system applied in the actual production is designed.The principle of the hydraulic system is analyzed and the hydraulic circuit and electric control circuit of the system is simulated by FluidSIM software.%针对压力机液压系统常见的振动及噪声问题,设计了应用于生产实际的压力机液压及控制系统,分析了液压系统原理,并利用FluidSIM软件对该系统的液压回路及电气控制回路进行仿真。


    Abdorahim Jamal


    Full Text Available Transient flow control in Water Transmission Systems (WTS is one of the requirements of designing these systems. Hence, among control equipment, air chambers offer the best solution to control transient flow effects, i.e. both prevents water column separation and absorbs pressure increase. It is essential to carry out an accurate and optimized design of air chambers, not only due to high costs of their manufacturing but also their important protective role. Accordingly, hydraulic design parameters comprise tank volume, diameter of nozzle and coefficients of inflow and outflow of nozzle. In this paper, it is intended to optimize these parameters in order to minimize manufacturing costs. On the other hand, maximum and minimum pressures in main pipeline are considered as constraints which shall fall in allowed range. Therefore, a model has been developed which is a combination of a hydraulic simulation model of WTS and an optimization model based on genetic algorithm. This model is first applied to WTS of Dehgolan-Ghorveh plain as a case study. Results of this research demonstrate that based on suggested model, negative wave creation and pressure increase in pipeline is prevented as well as decrease in manufacturing costs of air chamber.

  3. Thermal hydraulics of accelerator driven system windowless targets

    Bruno ePanella


    Full Text Available The study of the fluid dynamics of the windowless spallation target of an Accelerator Driven System (ADS is presented. Several target mockup configurations have been investigated: the first one was a symmetrical target, that was made by two concentric cylinders, the other configurations are not symmetrical. In the experiments water has been used as hydraulic equivalent to lead-bismuth eutectic fluid. The experiments have been carried out at room temperature and flow rate up to 24 kg/s. The fluid velocity components have been measured by an ultrasound technique. The velocity field of the liquid within the target region either for the approximately axial-symmetrical configuration or for the not symmetrical ones as a function of the flow rate and the initial liquid level is presented. A comparison of experimental data with the prediction of the finite volume FLUENT code is also presented. Moreover the results of a 2D-3D numerical analysis that investigates the effect on the steady state thermal and flow fields due to the insertion of guide vanes in the windowless target unit of the EFIT project ADS nuclear reactor are presented, by analysing both the cold flow case (absence of power generation and the hot flow case (nominal power generation inside the target unit.

  4. Engineered Barrier Systems Thermal-Hydraulic-Chemical Column Test Report

    W.E. Lowry


    The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M&O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01.

  5. Simulation research on hydraulic transformer system fault of 300 MN die forging hydraulic press%300MN模锻液压机液压变压系统故障仿真研究

    刘石梅; 谭建平; 陈晖


    In order to analyze the fault of hydraulic transformer which failed to work in long-stroke pressurizing because of its too long return time, a simulation model about hydraulic transformer system of 300 MN forging hydraulic press was established based on AMESim software. The influence of opening height of drain valves and pressure of liquidfilled tank on the return time of hydraulic transformer was simulated quantitatively. The condition, which would result in fault, was obtained and used to analyze the actual fault. The result shows that the fault can be eliminated through reducing the space between the cam plunger and drain valve stem by 4. 6 mm.Keywords: die forging hydraulic press; hydraulic transformer; simulationDesign and manufacture of multi-transfer hydraulic press with resistant-bias loading and synchronization mechanismAbstract: Multi-transfer hydraulic press, a kind of hydraulic equipment with the compact structure and high-efficiency,is widely used in sheet metal shaping and forming operations in the developed countries. To the problem appeared in multi-transfer hydraulic press, such as the wide table, serious bias loading and high-precision forming etc., a four-column multi-transfer hydraulic press developed for the forming of auto parts and components was designed and introduced. Through the research and analysis to the mainframe structure style and closed loop electric-hydraulic control system, the stationary motion performances as well as the integrated performances of equipment were improved and the resistant-bias loading capacity was enhanced in order to meet the high accuracy and compaction requirements.%针对300 MN模锻液压机实际生产中存在的变压器回程时间过长而无法长行程加压故障,基于AMESim软件建立了变压系统的仿真模型并进行了故障仿真,定量地得到了变压器操纵分配器排水阀开启度与充液罐压力对回程时间的影响规律.推导出变压器发生无法长行程加压故


    YAO Jianjun; WANG Liquan; JIANG Hongzhou; WU Zhenshun; HAN Junwei


    Since the dead zone phenomenon occurs in electro-hydraulic servo system, the output of the system corresponding to a sinusoidal input contains higher harmonic besides the fundamental input, which causes harmonic distortion of the output signal. The method for harmonic cancellation based on adaptive filter is proposed. The task is accomplished by generating reference signals with frequency that should be eliminated from the output. The reference inputs are weighted by the adaptive filter in such a way that it closely matches the harmonic. The output of the adaptive filter is a harmonic replica and is injected to the fundamental signal such that the output harmonic is cancelled leaving the desired signal alone, and the total harmonic distortion (THD) is greatly reduced. The weights of filter are adjusted on-line according to the control error by using least-mean-square (LMS) algorithm. Simulation results performed with a hydraulic system demonstrate the efficiency and validity of the proposed adaptive feed-forward compensator (AFC) control scheme.

  7. Digging Soil Experiments for Micro Hydraulic Excavators based on Model Predictive Tracking Control

    Tomatsu, Takumi; Nonaka, Kenichiro; Sekiguchi, Kazuma; Suzuki, Katsumasa


    Recently, the increase of burden to operators and lack of skilled operators are the issue in the work of the hydraulic excavator. These problems are expected to be improved by autonomous control. In this paper, we present experimental results of hydraulic excavators using model predictive control (MPC) which incorporates servo mechanism. MPC optimizes digging operations by the optimal control input which is calculated by predicting the future states and satisfying the constraints. However, it is difficult for MPC to cope with the reaction force from soil when a hydraulic excavator performs excavation. Servo mechanism suppresses the influence of the constant disturbance using the error integration. However, the bucket tip deviates from a specified shape by the sudden change of the disturbance. We can expect that the tracking performance is improved by combining MPC and servo mechanism. Path-tracking controls of the bucket tip are performed using the optimal control input. We apply the proposed method to the Komatsu- made micro hydraulic excavator PC01 by experiments. We show the effectiveness of the proposed method through the experiment of digging soil by comparing servo mechanism and pure MPC with the proposed method.

  8. Pressure Regulation in Nonlinear Hydraulic Networks by Positive and Quantized Controls

    Persis, Claudio De; Kallesøe, Carsten Skovmose


    We investigate an industrial case study of a system distributed over a network, namely, a large-scale hydraulic network which underlies a district heating system. The network comprises an arbitrarily large number of components (valves, pipes, and pumps). After introducing the model for this class of

  9. Chapter 2. Mode-switching in Hydraulic Actuator Systems - An Experiment

    Andersen, Torben Ole; Conrad, Finn; Ravn, Anders P.;


    Experiments with mode-switching adaptive control of actuators to drive a hydraulic test robot.The research is a cooperation with IT, DTU within the IMCIA Research Programme supported by the Danish Technical Research Council, STVF.......Experiments with mode-switching adaptive control of actuators to drive a hydraulic test robot.The research is a cooperation with IT, DTU within the IMCIA Research Programme supported by the Danish Technical Research Council, STVF....

  10. Force Control Strategies in Hydraulically Actuated Legged Robots

    Hector Montes


    Full Text Available In this contribution, several strategies of force control have been proposed to be implemented and evaluated in ROBOCLIMBER, a quadruped robot of large dimensions. A first group of strategies proposed in this paper is based on impedance control, which is intended to adapt the foot-ground contact forces according to the experimentally specified damping ratio and the undamped natural frequency. A second control strategy of interest for many practical cases is called the parallel force/position control, which has one inner loop position control and two external control loops, one of force and another of position. A third group of control strategies is the posture stabilization for ROBOCLIMBER using the feedback of the ZMP calculation and the position of its legs. Finally, a control strategy for the control of a quasi-static gait using ZMP feedback is proposed and tested by simulation.

  11. Research on the improvement of nuclear safety -Thermal hydraulic tests for reactor safety system-

    Jung, Moon Kee; Park, Choon Kyung; Yang, Sun Kyoo; Chun, Se Yung; Song, Chul Hwa; Jun, Hyung Kil; Jung, Heung Joon; Won, Soon Yun; Cho, Yung Roh; Min, Kyung Hoh; Jung, Jang Hwan; Jang, Suk Kyoo; Kim, Bok Deuk; Kim, Wooi Kyung; Huh, Jin; Kim, Sook Kwan; Moon, Sang Kee; Lee, Sang Il [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)


    The present research aims at the development of the thermal hydraulic verification test technology for the safety system of the conventional and advanced nuclear power plant and the development of the advanced thermal hydraulic measuring techniques. In this research, test facilities simulating the primary coolant system and safety system are being constructed for the design verification tests of the existing and advanced nuclear power plant. 97 figs, 14 tabs, 65 refs. (Author).

  12. 基于FluidSIM-Hydraulic的注塑机液压回路控制分析%Control Analysis for Hydraulic Loop of Plastic Injection Molding Machine Based on FluidSIM-Hydraulic

    叶金玲; 周钦河; 黄诚


    Hydraulic control system of plastic injection molding machine was designed using FluidSIM⁃Hydraulic software. The structure and working principle of the plastic injection molding machine were introduced, its hydraulic loop and electric loop were de⁃signed and optimized. The plastic injection molding machine has gained good affection in actual production.%基于FluidSIM⁃Hydraulic软件对注塑机液压回路控制系统进行分析。介绍了注塑机的结构原理,并优化设计了液压回路及电气控制系统,通过二者有效的结合成功地将模拟仿真后的模型应用到了实际生产中,取得了良好的效果。

  13. Thermal-Hydraulic Experiments and Modelling for Advanced Nuclear Reactor Systems

    Song, C. H.; Chung, M. K.; Park, C. K. and others


    The objectives of the project are to study thermal hydraulic characteristics of reactor primary system for the verification of the reactor safety and to evaluate new safety concepts of new safety design features. To meet the research goal, several thermal hydraulic experiments were performed and related thermal hydraulic models were developed with the experimental data which were produced through the thermal hydraulic experiments. Followings are main research topics; - Multi-dimensional Phenomena in a Reactor Vessel Downcomer - Condensation Load and Thermal Mixing in the IRWST - Development of Thermal-Hydraulic Models for Two-Phase Flow - Development of Measurement Techniques for Two-Phase Flow - Supercritical Reactor T/H Characteristics Analysis From the above experimental and analytical studies, new safety design features of the advanced power reactors were verified and lots of the safety issues were also resolved.

  14. Incorporating Artificial Neural Networks in the dynamic thermal-hydraulic model of a controlled cryogenic circuit

    Carli, S.; Bonifetto, R.; Savoldi, L.; Zanino, R.


    A model based on Artificial Neural Networks (ANNs) is developed for the heated line portion of a cryogenic circuit, where supercritical helium (SHe) flows and that also includes a cold circulator, valves, pipes/cryolines and heat exchangers between the main loop and a saturated liquid helium (LHe) bath. The heated line mimics the heat load coming from the superconducting magnets to their cryogenic cooling circuits during the operation of a tokamak fusion reactor. An ANN is trained, using the output from simulations of the circuit performed with the 4C thermal-hydraulic (TH) code, to reproduce the dynamic behavior of the heated line, including for the first time also scenarios where different types of controls act on the circuit. The ANN is then implemented in the 4C circuit model as a new component, which substitutes the original 4C heated line model. For different operational scenarios and control strategies, a good agreement is shown between the simplified ANN model results and the original 4C results, as well as with experimental data from the HELIOS facility confirming the suitability of this new approach which, extended to an entire magnet systems, can lead to real-time control of the cooling loops and fast assessment of control strategies for heat load smoothing to the cryoplant.

  15. Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control


    Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV). ANAV is the consortium that runs the Ascó power plants (2 units) and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC) thermal-hydraulic analysis team has jointly worked togeth...

  16. Second Order Sliding Mode Control with Prescribed Convergence Law for Electro-Hydraulic Drives

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.


    This paper discusses the application of second order sliding modes for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The target is to introduce increased tracking- and transient performance compared to conventional linear approaches, without extending the number of...

  17. Wind tunnel experiments to prove a hydraulic passive torque control concept for variable speed wind turbines

    Diepeveen, N.F.B.; Jarquin-Laguna, A.


    In this paper the results are presented of experiments to prove an innovative concept for passive torque control of variable speed wind turbines using fluid power technology. It is demonstrated that by correctly configuring the hydraulic drive train, the wind turbine rotor operates at or near maximu



    A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. And a set of pressure controlling devices with PLC as a central processor are designed. It can be got from the relevant experiments that the pressure-stroke characteristic is correct and its control for forming process is available.

  19. Fuzzy robust nonlinear control approach for electro-hydraulic flight motion simulator

    Han Songshan; Jiao Zongxia; Wang Chengwen; Shang Yaoxing


    A fuzzy robust nonlinear controller for hydraulic rotary actuators in flight motion sim-ulators is proposed. Compared with other three-order models of hydraulic rotary actuators, the proposed controller based on first-order nonlinear model is more easily applied in practice, whose control law is relatively simple. It not only does not need high-order derivative of desired command, but also does not require the feedback signals of velocity, acceleration and jerk of hydraulic rotary actuators. Another advantage is that it does not rely on any information of friction, inertia force and external disturbing force/torque, which are always difficult to resolve in flight motion simula-tors. Due to the special composite vane seals of rectangular cross-section and goalpost shape used in hydraulic rotary actuators, the leakage model is more complicated than that of traditional linear hydraulic cylinders. Adaptive multi-input single-output (MISO) fuzzy compensators are introduced to estimate nonlinear uncertain functions about leakage and bulk modulus. Meanwhile, the decom-position of the uncertainties is used to reduce the total number of fuzzy rules. Different from other adaptive fuzzy compensators, a discontinuous projection mapping is employed to guarantee the estimation process to be bounded. Furthermore, with a sufficient number of fuzzy rules, the control-ler theoretically can guarantee asymptotic tracking performance in the presence of the above uncer-tainties, which is very important for high-accuracy tracking control of flight motion simulators. Comparative experimental results demonstrate the effectiveness of the proposed algorithm, which can guarantee transient performance and better final accurate tracking in the presence of uncertain nonlinearities and parametric uncertainties.

  20. Mode-2 hydraulic control of flow over a small ridge on a continental shelf

    Gregg, M. C.; Klymak, Jody M.


    Some of the most intense turbulence in the ocean occurs in hydraulic jumps formed in the lee of sills where flows are hydraulically controlled, usually by the first internal mode. Observations on the outer Texas-Louisiana continental shelf reveal hydraulic control of internal mode-2 lasting more than 3 h over a 20 m high ridge on the 100 m deep continental shelf. When control began the base of the weakly stratified surface layer bulged upward and downward, a signature of mode-2. As the westward flow producing control was lost, large-amplitude disturbances, initially resembling a bore in the weakly stratified layer, began propagating eastward. Average dissipation rates inferred from density inversions over the ridge were 10-8 and 10-7W kg-1, one to two decades above local background. Corresponding diapycnal diffusivities, Kρ, were 10-4 to 10-3 m2 s-1. Short-term mixing averages did not evolve systematically with hydraulic control, possibly owing to our inability to observe small overturns in strongly stratified water directly over the ridge. To test the feasibility of our interpretation of the observations, hydrostatic runs with a three-dimensional MITgcm simulated mode-2 control and intense mixing over the ridge below the interface. Details differed from observations, principally because we lacked three-dimensional density fields to initialize the model which was forced with currents observed by a bottom-mounted ADCP several kilometers east of the ridge. Consequently, the model did not capture all flow features around the bank. The principal conclusion is that hydraulic responses to higher modes can dominate flows around even modest bathymetric irregularities.

  1. 后装压缩式垃圾车专用装置液压系统反馈控制仿真研究%Simulation Study on Feedback Control of Special Device Hydraulic System for Back-loaded and Compressed Refuse Collector



    应用AMESim对后装压缩式垃圾车专用装置反馈控制系统进行建模与仿真,对比分析了开环、闭环专用装置的运动特性.仿真结果表明:反馈控制系统可明显改善专用装置的运动状况,为提高专用装置的设计水平提供了参考.%Modeling and simulation of feedback control of special device hydraulic system for back-loaded and compressed refuse collector were carried out by AMEsim. Kinematic characteristics for opening loop and closed loop control system were compared and analyzed. The simulation results show that the feedback control system has good kinematic quality. It provides references for advancing the special device design level.

  2. Reliability and safety of the K Reactor cooling system: Part 2, Engineering analysis of hydraulic and mechanical aspects

    Shoemaker, R.H.


    Subsequent to the recent formulation and adoption of safety criteria for reactor cooling systems, there appeared the need for an independent evaluation of the safety and reliability of the K-Reactor cooling system in terms of these criteria. The primary, secondary and last-ditch cooling systems of this reactor involve a strong inter-dependence between electrical and hydraulic components of the water plant. Because of the complexity of inter-relationships between these components, the analysis was divided into two parallel studies which were accomplished during the simmer of 1959. F. D. Robbins has presented his analysis of the electrical power and control system in HW-61887. This report deals with an engineering analysis of the hydraulic and mechanical aspects of the reliability and safety of the K-Reactor Cooling System. The system, as described in this report, is that which existed during the simmer of 1959, prior to modification under Project CG-775 (now Project CG-883).

  3. Fuzzy robust nonlinear control approach for electro-hydraulic flight motion simulator

    Han Songshan


    Full Text Available A fuzzy robust nonlinear controller for hydraulic rotary actuators in flight motion simulators is proposed. Compared with other three-order models of hydraulic rotary actuators, the proposed controller based on first-order nonlinear model is more easily applied in practice, whose control law is relatively simple. It not only does not need high-order derivative of desired command, but also does not require the feedback signals of velocity, acceleration and jerk of hydraulic rotary actuators. Another advantage is that it does not rely on any information of friction, inertia force and external disturbing force/torque, which are always difficult to resolve in flight motion simulators. Due to the special composite vane seals of rectangular cross-section and goalpost shape used in hydraulic rotary actuators, the leakage model is more complicated than that of traditional linear hydraulic cylinders. Adaptive multi-input single-output (MISO fuzzy compensators are introduced to estimate nonlinear uncertain functions about leakage and bulk modulus. Meanwhile, the decomposition of the uncertainties is used to reduce the total number of fuzzy rules. Different from other adaptive fuzzy compensators, a discontinuous projection mapping is employed to guarantee the estimation process to be bounded. Furthermore, with a sufficient number of fuzzy rules, the controller theoretically can guarantee asymptotic tracking performance in the presence of the above uncertainties, which is very important for high-accuracy tracking control of flight motion simulators. Comparative experimental results demonstrate the effectiveness of the proposed algorithm, which can guarantee transient performance and better final accurate tracking in the presence of uncertain nonlinearities and parametric uncertainties.

  4. Experimental Study of a Small Scale Hydraulic System for Mechanical Wind Energy Conversion into Heat

    Tadas Zdankus


    Full Text Available Significant potential for reducing thermal energy consumption in buildings of moderate and cold climate countries lies within wind energy utilisation. Unlike solar irradiation, character of wind speeds in Central and Northern Europe correspond to the actual thermal energy demand in buildings. However, mechanical wind energy undergoes transformation into electrical energy before being actually used as thermal energy in most wind energy applications. The study presented in this paper deals with hydraulic systems, designed for small-scale applications to eliminate the intermediate energy transformation as it converts mechanical wind energy into heat directly. The prototype unit containing a pump, flow control valve, oil tank and piping was developed and tested under laboratory conditions. Results of the experiments showed that the prototype system is highly efficient and adjustable to a broad wind velocity range by modifying the definite hydraulic system resistance. Development of such small-scale replicable units has the potential to promote “bottom-up” solutions for the transition to a zero carbon society.

  5. Linear Perturbation Adaptive Control of Hydraulically Driven Manipulators

    Andersen, T.O.; Hansen, M.R.; Conrad, Finn


    control.Using the Lyapunov approach, under slowly time-varying assumptions, it is shown that the tracking error and the parameter error remain bounded. This bound is a function of the ideal parameters and a bounded disturbance. The control algorithm decouples and linearizes the manipulator so that each...

  6. Hydraulic resistance partitioning between shoot and root system and plant water status of Haloxyolon ammodendron growing at sites of contrasting soil texture


    Hydraulic resistance components and water relations were studied on Haloxyolon ammoden-dron,a small xeric tree,growing at sites significantly differed in soil texture.Soil water content,leaf water potential(ψl),xylem water potential(ψx),root water potential(ψroot),leaf transpiration rate(TR) and stomatal conductance(gs) were measured at the two sites during the growing season of 2005 and 2006.Leaf spe-cific hydraulic resistance(Rplant) during the whole growing season,hydraulic resistance of plants(Rp),shoots(Rshoot) and roots(Rroot) in the August of both years were calculated and expressed on leaf area basis.The results showed the proportion of the hydraulic resistance of the aerial part(Rshoot) to the Rp was the same to the proportion of the hydraulic resistance of the soil part(Rroot) to the Rp,indicating that both parts were equivalent important to plant water hydraulic system from soil to leaf.Positive significant corre-lations were found between Rp and Rroot,suggesting that root hydraulics resistance was a major determinant of plant hydraulic resistance(Rp) and transpiration rate.The integrated effect of stomatal control,hy-draulic regulation and morphology adjustment enabled plants at heavy soil site surviving the extreme water deficit period.

  7. Parameters Matching and Control Method of Hydraulic Hybrid Vehicles with Secondary Regulation Technology

    SUN Hui; JIANG Jihai; WANG Xin


    Hydraulic hybrid vehicles (HHV) with secondary regulation technology has the potential of improving fuel economy by operating the engine in the optimum efficiency range and making use of regenerative braking. Hydrostatic transmission technology has the advantage of higher power density and the ability to accept the high rates and high frequencies of charging and discharging, both of which are not favorable for batteries, but the lower energy density requires special power matching design and control strategy to coordinate all the powertrain components in an optimal manner. A multi-objective optimization method is proposed to distinguish the components size values of HHV by considering the requirements of driving cycles and technology aspects. The regenerative braking strategy and energy control strategy based on the optimized HHV is proposed to recovery the braking energy and distribute the regenerated braking energy. Simulation results show that by taking the optimized configuration of HHV, adopting the regenerative braking strategy and energy control strategy are helpful to improve the system efficiency and fuel economy of HHV under urban driving cycles.

  8. Design of Electric-hydraulic Control Butterfly Valve%电液动调节蝶阀的设计

    王建新; 张逸芳


    Introduced process design、main content and key factors to consider of the electro-hydraulic control valve ,Discusses the points for attention and suggestions of valve body,actuator,control system design and calculation.%介绍了电液动调节蝶阀方案设计的过程、主要内容及考虑的关键因素,论述了阀门本体、执行机构、控制系统等设计计算的关注点及建议。

  9. A quantitative analysis of hydraulic interaction processes in stream-aquifer systems.

    Wang, Wenke; Dai, Zhenxue; Zhao, Yaqian; Li, Junting; Duan, Lei; Wang, Zhoufeng; Zhu, Lin


    The hydraulic relationship between the stream and aquifer can be altered from hydraulic connection to disconnection when the pumping rate exceeds the maximum seepage flux of the streambed. This study proposes to quantitatively analyze the physical processes of stream-aquifer systems from connection to disconnection. A free water table equation is adopted to clarify under what conditions a stream starts to separate hydraulically from an aquifer. Both the theoretical analysis and laboratory tests have demonstrated that the hydraulic connectedness of the stream-aquifer system can reach a critical disconnection state when the horizontal hydraulic gradient at the free water surface is equal to zero and the vertical is equal to 1. A boundary-value problem for movement of the critical point of disconnection is established for an analytical solution of the inverted water table movement beneath the stream. The result indicates that the maximum distance or thickness of the inverted water table is equal to the water depth in the stream, and at a steady state of disconnection, the maximum hydraulic gradient at the streambed center is 2. This study helps us to understand the hydraulic phenomena of water flow near streams and accurately assess surface water and groundwater resources.

  10. Time delay control of hydraulic manipulators with continuous nonsingular terminal sliding mode

    王尧尧; 陈家旺; 顾临怡; 李晓东


    For the position tracking control of hydraulic manipulators, a novel method of time delay control (TDC) with continuous nonsingular terminal sliding mode (CNTSM) was proposed in this work. Complex dynamics of the hydraulic manipulator is approximately canceled by time delay estimation (TDE), which means the proposed method is model-free and no prior knowledge of the dynamics is required. Moreover, the CNTSM term with a fast-TSM-type reaching law ensures fast convergence and high-precision tracking control performance under heavy lumped uncertainties. Despite its considerable robustness against lumped uncertainties, the proposed control scheme is continuous and chattering-free and no pressure sensors are required in practical applications. Theoretical analysis and experimental results show that faster and higher-precision position tracking performance is achieved compared with the traditional CNTSM-based TDC method using boundary layers.

  11. For God (or) country: the hydraulic relation between government instability and belief in religious sources of control.

    Kay, Aaron C; Shepherd, Steven; Blatz, Craig W; Chua, Sook Ning; Galinsky, Adam D


    It has been recently proposed that people can flexibly rely on sources of control that are both internal and external to the self to satisfy the need to believe that their world is under control (i.e., that events do not unfold randomly or haphazardly). Consistent with this, past research demonstrates that, when personal control is threatened, people defend external systems of control, such as God and government. This theoretical perspective also suggests that belief in God and support for governmental systems, although seemingly disparate, will exhibit a hydraulic relationship with one another. Using both experimental and longitudinal designs in Eastern and Western cultures, the authors demonstrate that experimental manipulations or naturally occurring events (e.g., electoral instability) that lower faith in one of these external systems (e.g., the government) lead to subsequent increases in faith in the other (e.g., God). In addition, mediation and moderation analyses suggest that specific concerns with order and structure underlie these hydraulic effects. Implications for the psychological, sociocultural, and sociopolitical underpinnings of religious faith, as well as system justification theory, are discussed.

  12. Discrete Learning Control with Application to Hydraulic Actuators

    Andersen, Torben Ole; Pedersen, Henrik Clemmensen; Hansen, Michael R.


    In this paper the robustness of a class of learning control algorithms to state disturbances, output noise, and errors in initial conditions is studied. We present a simple learning algorithm and exhibit, via a concise proof, bounds on the asymptotic trajectory errors for the learned input and th...


    Hennadii Zaionchkovskyi


    Full Text Available In aviation hydraulic drive of high power as a power supply the axial-piston variable displacement pumps became wide spreaded. The pump operational modes with air isolation and cavitation are accompanied by increased noise, delivery reduction and intensive pressure oscillations. The negative results of such phenomena are hydraulic elements erosion, pipeline fatigue failure, working fluid viscosity reduction and its contamination by wear products. The mechanism of cavitation rising in axial-piston pumps is considered, and factors which influence the cavitation rising and working fluid aeration are specified. The features of transient processes in aircraft hydraulic systems with variable displacement pumps are considered. It has been showed that as the pump delivery changes from its minimum to maximum great pressure oscillations in the aircraft pressure pipeline of the hydraulic system takes place, and have a negative influence on the pump service life. The recommendations concerning such pressure oscillation reduction are given.

  14. PLC程序控制研配液压机的结构设计%Structure Design of Bedding-in Hydraulic Press Controlled by PLC Program

    刘泽民; 付丽; 敖茜; 李慧


    The design scheme of bedding-in hydraulic press controlled by PLC was introduced. The bedding-in process,struc-ture,hydraulic system and PLC control process of the bedding-in hydraulic press were analyzed. The program significantly improves the control precision and production efficiency.%介绍了应用PLC技术的研配液压机的设计方案,对该机的研配过程、结构、液压系统和PLC控制过程进行了分析和说明。该方案的提出显著提高了控制精度和生产效率。

  15. Research on Pressure Shock in Hydraulic System%液压系统中的压力冲击研究



    Based on theoretical calculation and simulation analysis, this paper got the key factor which affect the pressure shock in valve-control hydraulic system. Then concluded how the tube length and valve open-time affect pressure shock in hydraulic system. And the conclusions were verified based on test. It showed that tube length and valve open-time affect pressure shock in hydraulic system directly. The research also showed that shortening tube length and increasing valve open-time properly can reduce pressure shock effectively. All above provide the direction for the layout and design of hydraulic system part/product, and also provide theoretical basis for optimizing hydraulic system.%通过理论计算和仿真分析,研究影响阀控液压系统压力冲击的关键因素,得出阀控液压系统中的压力冲击与管路长度、阀开启时间的关系,并进行试验验证。结果表明,管路长度、阀开启时间直接影响着阀控液压系统中的压力冲击。缩短管路长度和适当延长阀开启时间,都能有效减小阀控系统中的压力冲击。这为飞机液压系统中元部件的布局和设计提供了方向,为飞机液压系统的完善和优化提供了依据。

  16. Development of semi-active hydraulic damper as active interaction control device to withstand external excitation

    Ming-Hsiang Shih; Wen-Pei Sung


    Semi-automatic control systems have the characteristics of being adaptable and requiring low energy. The objective of this research was to study the performance of an improved DSHD (Displacement Semi-Active Hydraulic Damper) by converting it to AIC (Active Interaction Control Device) with the addition of an accumulator. The prototype was tested using full-scale elements for examining the structural displacement, and typical responses of the interacting interface element developed in this research, the pressure variation of the pressure storage device, and the energy dissipation hysteresis loop when the structure installed with these elements is subjected to external force of various magnitude. The laboratory results confirm that the device developed in this research is capable of applying the energy dissipation characteristics of DSHD so that these elements are appropriate for developing the proposed AIC. The mutual interaction between the subordinate structure and the main structure to be protected is capable of transforming the quake energy applied to the main structure to the subordinate structure so that the objective of minimizing the deformation of main structural can be achieved.

  17. International approaches to the hydraulic control of surface water runoff in mitigating flood and environmental risks

    Ballard Bridget Woods


    Full Text Available This paper compares and contrasts a number of international approaches to the hydraulic control of surface water runoff from new development and redevelopment, known as sustainable drainage systems (SuDS or low impact development (LID. The paper provides a commentary on the progress and current status of national standards for SuDS in the UK to control the frequency, flow rate and volume of runoff from both frequent and extreme rainfall events, and the best practice design criteria presented in the revised UK CIRIA SuDS Manual, published in November 2015. The paper then compares these design criteria and standards with those developed and applied in China, USA, France and Germany and also looks at the drivers behind their development. The benefits of these different approaches are assessed in the context of flood risk mitigation, climate resilience and wider environmental protection objectives, including water quality, morphology and ecology. The paper also reviews the design approaches promoted by the new SuDS Manual and internationally for delivering additional benefits for urban spaces (such as recreation, visual character, education and economic growth through multi-functional urban design.

  18. Hydraulic analysis of water supply networks and controlling the leak using WATER GEMS model

    Mahmood Motevalizadeh


    Full Text Available Given that the discussion on water is strategic in terms of economic and social aspects as well as environmental impact, water leak in urban water-supply systems is very important, so, dealing with it is necessary and inevitable. Controlling and reducing water leak are of the main goals of water supplier organization due to limitations in terms of water resources, especially in dry lands which have few water resources. Pressure management is an efficient tool to reduce costs, enhance the operation of the network and therefore, it reduces the leak and increases the life of facilities and equipment and reduces the number of accidents. Smart pressure containment is a good way to prevent excess pressure in network to control undesirable phenomenon of leak which is directly related to pressure. In this study, Badamuiyeh water supply complex in Kerman City was selected to study on adjusting the pressure to control the leak of water and the hydraulic analysis was performed with demand-based method (DDSM, which is common technique and demand is constant, by Water GEMS software. For this end, the pressure reducing valves (prv were installed in critical point and they were timed to provide standard pressure in all nodes of the network and then, the impact of smart pressure management on water supply system has been investigated. Then its impact on the leak was examined and the results show that smart pressure control through pressure-reducing valve is a proper method for optimal management of water and reducing the leak significantly that with 45.15% reduction in average pressure, one can reduce the leak as much as 25.67% that as its result, 15380 m3 of water is annually saved in this region which is equal to 27.18% of consuming water.

  19. Speed-variable Switched Differential Pump System for Direct Operation of Hydraulic Cylinders

    Schmidt, Lasse; Roemer, Daniel Beck; Pedersen, Henrik Clemmensen


    proportional valves, this design allows to control the lower chamber pressure levels, throttling excess compression flow to tank. The resulting design introduces additional losses due to throttling of excess compression flow, but also improves the dynamic properties of the system significantly. The proposed...... gear pumps, the throttling losses are confined to cross port leakage in the cylinder and leakage of the pumps. However, it turns out that the volumetric pump losses and the pressure dynamics of the cylinder and connecting pipes may cause pressure increase- or decrease in the cylinder chambers, which...... may seriously influence the dynamics and hence the performance during operation. This paper presents an analysis of these properties, and a redesign of the hydraulic system concept is proposed. Here the area- and displacement ratios are deliberately mismatched, causing inherent pressure build...

  20. How far can various control options take us in terms of increased hydraulic capacity under wet weather conditions?

    Sharma, Anitha Kumari; Guildal, T.; Thomsen, H. A. R.

    Many modelling studies have demonstrated that the hydraulic capacity of the WWTP can be improved by introducing various real time control options, however few studies have demonstrated how effective these controls are in the real world.......Many modelling studies have demonstrated that the hydraulic capacity of the WWTP can be improved by introducing various real time control options, however few studies have demonstrated how effective these controls are in the real world....

  1. Primary system thermal hydraulics of future Indian fast reactors

    Velusamy, K., E-mail: [Thermal Hydraulics Section, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Natesan, K.; Maity, Ram Kumar; Asokkumar, M.; Baskar, R. Arul; Rajendrakumar, M.; Sarathy, U. Partha; Selvaraj, P.; Chellapandi, P. [Thermal Hydraulics Section, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Kumar, G. Senthil; Jebaraj, C. [AU-FRG Centre for CAD/CAM, Anna University, Chennai 600 025 (India)


    Highlights: • We present innovative design options proposed for future Indian fast reactor. • These options have been validated by extensive CFD simulations. • Hotspot factors in fuel subassembly are predicted by parallel CFD simulations. • Significant safety improvement in the thermal hydraulic design is quantified. - Abstract: As a follow-up to PFBR (Indian prototype fast breeder reactor), many FBRs of 500 MWe capacity are planned. The focus of these future FBRs is improved economy and enhanced safety. They are envisaged to have a twin-unit concept. Design and construction experiences gained from PFBR project have provided motivation to achieve an optimized design for future FBRs with significant design changes for many critical components. Some of the design changes include, (i) provision of four primary pipes per primary sodium pump, (ii) inner vessel with single torus lower part, (iii) dome shape roof slab supported on reactor vault, (iv) machined thick plate rotating plugs, (v) reduced main vessel diameter with narrow-gap cooling baffles and (vi) safety vessel integrated with reactor vault. This paper covers thermal hydraulic design validation of the chosen options with respect to hot and cold pool thermal hydraulics, flow requirement for main vessel cooling, inner vessel temperature distribution, safety analysis of primary pipe rupture event, adequacy of decay heat removal capacity by natural convection cooling, cold pool transient thermal loads and thermal management of top shield and reactor vault.

  2. Pressure Control of Electro-Hydraulic Servovalve and Transmission Line Effect

    Ahmed Fouad Mahdi


    Full Text Available The effected of the long transmission line (TL between the actuator and the hydraulic control valve sometimes essentials. The study is concerned with modeling the TL which carries the oil from the electro-hydraulic servovalve to the actuator. The pressure value inside the TL has been controlled by the electro-hydraulic servovalve as a voltage supplied to the servovalve amplifier. The flow rate through the TL has been simulated by using the lumped π element electrical analogy method for laminar flow. The control voltage supplied to servovalve can be achieved by the direct using of the voltage function generator or indirect C++ program connected to the DAP-view program built in the DAP-card data acquisition connected to PC, to control the value of pressure in a selected point in the TL. It has been found that the relation between the voltage value and the output flow rate from the servovalve in most of the path is a linear relation. The MATLAB m-File program is used to create a representation state of the mathematical model to find a good simulation for the experimental open loop control test.



    The tele-operation robotic system which consists of an excavator as the construction robot, and two joysticks for operating the robot from a safe place are useful for performing restoration in damaged areas. In order to accomplish a precise task, the operator needs to feel a realistic sense of task force brought about from a feedback force between the fork glove of slave robot and unfamiliar environment. A novel force feedback model is proposed based on velocity control of cylinder to determine environment force acting" on fork glove. Namely, the feedback force is formed by the error of displacement of joystick with velocity and driving force of piston, and the gain is calculated by the driving force and threshold of driving force of hydraulic cylinder. Moreover, the variable gain improved algorithm is developed to overcome the defect for grasping soft object. Experimental results for fork glove freedom of robotic system are provided to demonstrate the developed algorithm is available for grasping soft object.

  4. Discrete Displacement Hydraulic Power Take-Off System for the Wavestar Wave Energy Converter

    Enrique Vidal


    Full Text Available The Wavestar Wave Energy Converter (WEC is a multiple absorber concept, consisting of 20 hemisphere shaped floats attached to a single platform. The heart of the Wavestar WEC is the Power Take-Off (PTO system, converting the wave induced motion of the floats into a steady power output to the grid. In the present work, a PTO based on a novel discrete displacement fluid power technology is explored for the Wavestar WEC. Absorption of power from the floats is performed by hydraulic cylinders, supplying power to a common fixed pressure system with accumulators for energy smoothing. The stored pressure energy is converted into electricity at a steady pace by hydraulic motors and generators. The storage, thereby, decouples the complicated process of wave power absorption from power generation. The core for enabling this PTO technology is implementing a near loss-free force control of the energy absorbing cylinders. This is achieved by using special multi-chambered cylinders, where the different chambers may be connected to the available system pressures using fast on/off valves. Resultantly, a Discrete Displacement Cylinder (DDC is created, allowing near loss free discrete force control. This paper presents a complete PTO system for a 20 float Wavestar based on the DDC. The WEC and PTO is rigorously modeled from incident waves to the electric output to the grid. The resulting model of +600 states is simulated in different irregular seas, showing that power conversion efficiencies above 70% from input power to electrical power is achievable for all relevant sea conditions.

  5. Directional hydraulic fracturing to control hard-roof rockburst in coal mines

    Fan Jun; Dou Linming; He Hu; Du Taotao; Zhang Shibin; Gui Bing; Sun Xinglin


    Hard roof is the main factor that induces rock-burst.In view of the present obvious weakness of control measures for hard roof rockburst in domestic collieries,the mechanism and field application of directional hydraulic fracturing technology for rock-burst prevention have been investigated in this paper using theoretical analysis and numerical simulation.The results show that the weighting span of the main roof and the released kinetic energy as well as the total elastic energy decreased greatly after the directional fracturing of hard roof with the mining progression,thereby reducing the rockburst hazard degree to coal body.The directional hydraulic fracturing technology was carried out in 6305 working face of Jisan Coal Mine to prevent rockburst.Field practices have proved that this technology is much simpler and safer to operate with better prevention effect compared with blasting.By optimizing the operation procedures and developing a new technology of automated high-pressure delivery pipe,the maximum fracturing radius now reaches more than 9 m and the borehole depth exceeds 20 m.Additionally,drilling cutting method was applied to monitor the stress of the coal mass before and after the fracturing,and the drill cuttings dropped significantly which indicates that the burst prevention effect of directional hydraulic fracturing technology is very remarkable.The research results of this paper have laid a theoretical and practical foundation for the widespread application of the directional hydraulic fracturing technology in China.

  6. Application of flow network models of SINDA/FLUINT{sup TM} to a nuclear power plant system thermal hydraulic code

    Chung, Ji Bum [Institute for Advanced Engineering, Yongin (Korea, Republic of); Park, Jong Woon [Korea Electric Power Research Institute, Taejon (Korea, Republic of)


    In order to enhance the dynamic and interactive simulation capability of a system thermal hydraulic code for nuclear power plant, applicability of flow network models in SINDA/FLUINT{sup TM} has been tested by modeling feedwater system and coupling to DSNP which is one of a system thermal hydraulic simulation code for a pressurized heavy water reactor. The feedwater system is selected since it is one of the most important balance of plant systems with a potential to greatly affect the behavior of nuclear steam supply system. The flow network model of this feedwater system consists of condenser, condensate pumps, low and high pressure heaters, deaerator, feedwater pumps, and control valves. This complicated flow network is modeled and coupled to DSNP and it is tested for several normal and abnormal transient conditions such turbine load maneuvering, turbine trip, and loss of class IV power. The results show reasonable behavior of the coupled code and also gives a good dynamic and interactive simulation capabilities for the several mild transient conditions. It has been found that coupling system thermal hydraulic code with a flow network code is a proper way of upgrading simulation capability of DSNP to mature nuclear plant analyzer (NPA). 5 refs., 10 figs. (Author)

  7. Hybrid position/force and positional accuracy controller for a hydraulic manipulator

    Unruh, Stanley G.; Faddis, Terry N.; Greenway, Bryan R.; Hibbard, Wilthea


    A hybrid position/force controller is presented for a 6 DOF hydraulic manipulator. The controller has been implemented on a Kraft telerobotic slave which has been modified to accommodate a 6 DOF force/torque sensor at the wrist. The controller is implemented within the task frame, and both the position and force are controlled with a non-conventional hybrid control method. Positional accuracy control is maintained at the joint level by using a joint error prediction method based on measured joint torques which have been low-pass filtered. This prediction method eliminates the need for integral gains, which introduce unwanted limit cycling. Dynamic stability is maintained and Cartesian positional error is held to less than 0.2 inches. Conventional hybrid control is based on the ability to control joint torques, but hydraulic actuator torque can not generally be directly controlled. We instead employ a feedback loop which adjusts positional commands along force controlled DOFs until desired end effector force/,moments have been realized. This feedback loop has been implemented in both joint and Cartesian space. The joint space feedback method is based on the observed joint error verses joint torque characteristics used in the positional accuracy control portion. The joint space method has better force tracking capabilities than the Cartesian method, but is not stable for all robot configurations. Cartesian space feedback method has sufficient force tracking for a useful range of tasks, and is stable for all configurations.

  8. Design, Optimization and Analysis of Hydraulic Soft Yaw System for 5 MW Wind Turbine

    Stubkier, Søren; Pedersen, Henrik C.


    presents work previous done on this subject with focus on hydraulic yaw systems. By utilizing the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized. Results show that a significant...... reduction in fatigue and extreme loads to the yaw system and rotor shaft are possible, when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. The duty cycles, based...... on the extrapolated loads, show that it is possible to construct a hydraulic soft yaw system, which is able to reduce the loads on the wind turbine significantly....

  9. Application of Multi-cylinders Synchronization Hydraulic Servo Control in the Coil-Press%多缸同步液压伺服控制系统在线圈压床的应用

    陈彪; 姜新生


    介绍了多缸同步液压伺服控制系统在线圈压床中的组成、控制原理,及在线圈压床中的实际应用效果.%The components of multi-cylinders synchronization hydraulic servo control in the coil-press and controlled theory of hydraulic servo control system were introduced. Its infect of actual used in the coil-press was presented.

  10. Determination and discussion hydraulic retention time in membrane bioreactor system


    Based on the microorganism kinetic model, the formulafor computing hydraulic retention time in a membrane bioreactorsystem (MBR) is derived. With considering HRT as an evaluationindex a combinational approach was used to discuss factors whichhave an effect on MBR. As a result, the influencing factors werelisted in order from strength to weakness as: maximum specificremoval rate K, saturation constant Ks, maintenance coefficient m,Moreover, the formula was simplified, whose parameters wereexperimentally determined in petrochemical wastewater treatment. The simplified formula is (=1.1((1/(-1)(Ks+S)/KX0, forpetrochemical wastewater treatment K and Ks equaled 0.185 and154.2, respectively.

  11. Plant hydraulic controls over ecosystem responses to climate-enhanced disturbances

    Mackay, D. S.; Ewers, B. E.; Reed, D. E.; Pendall, E.; McDowell, N. G.


    Climate-enhanced disturbances such as drought and insect infestation range in severity, contributing minor to severe stress to forests including forest mortality. While neither form of disturbance has been unambiguously implicated as a mechanism of mortality, both induce changes in water, carbon, and nutrient cycling that are key to understanding forest ecosystem response to, and recovery from, disturbance. Each disturbance type has different biophysical, ecohydrological, and biogeochemical signatures that potentially complicate interpretation and development of theory. Plant hydraulic function is arguably a unifying control over these responses to disturbance because it regulates stomatal conductance, leaf biochemistry, carbon (C) uptake and utilization, and nutrient cycling. We demonstrated this idea by focusing on water and C, including non-structural (NSC), resources, and nitrogen (N) uptake across a spectrum of forest ecosystems (e.g., northern temperate mixed forests, lodgepole pine forests in the Rocky Mountains, and pinon pine - juniper woodlands in New Mexico) using the Terrestrial Regional Ecosystem Exchange Simulator (TREES). TREES is grounded in the biophysics of water movement through soil and plants, respectively via hydraulic conductivity of the soil and cavitation of xylem. It combines this dynamic plant hydraulic conductance with canopy biochemical controls over photosynthesis, and the dynamics of structural and non-structural carbon through a carbon budget that responds to plant hydraulic status. As such, the model can be used to develop testable hypotheses on a multitude of disturbance and recovery responses including xylem dysfunction, stomatal and non-stomatal controls on photosynthesis and carbon allocation, respiration, and allocation to defense compounds. For each of the ecosystems we constrained and evaluated the model with allometry, sap flux and/or eddy covariance data, leaf gas exchange measurements, and vulnerability to cavitation data

  12. Guiding-controlling technology of coal seam hydraulic fracturing fractures extension

    Zhai; Cheng; Li; Min; Sun; Chen; Zhang; Jianguo; Yang; Wei; Li; Quangui


    Aiming at the uncontrollable problem of extension direction of coal seam hydraulic fracturing,this study analyzed the course of fractures variation around the boreholes in process of hydraulic fracturing,and carried out the numerical simulations to investigate the effect of artificial predetermined fractures on stress distribution around fractured holes.The simulation results show that partial coal mass occurs relatively strong shear failure and forms weak surfaces,and then fractures extended along the desired direction while predetermined fractures changed stress distribution.Directional fracturing makes the fractures link up and the pressure on coal mass is relieved within fractured regions.Combining deep hole controlling blasting with hydraulic fracturing was proposed to realize the extension guiding-controlling technology of coal seam fractures.Industrial experiments prove that this technology can avoid local stress concentration and dramatically widen the pressure relief scope of deep hole controlling blasting.The permeability of fractured coal seam increased significantly,and gas extraction was greatly improved.Besides,regional pressure relief and permeability increase was achieved in this study.

  13. Tuning of PID parameters of positive displacement speed control system of pump-controlled hydraulic motor%泵控液压马达容积调速系统的PID参数整定

    袁建畅; 任京芹


    分别通过Z-N整定方法与Matlab/Simulink中的非线性控制设计模块(Nonlinear Control Design,NCD),对泵控马达容积调速系统中的比例-积分-微分参数(Proportion Integration Differentiation,PID)进行优化设计.仿真结果表明,采用NCD优化后的PID参数有效地改善了系统的性能,所得结果可作为实际调速系统参数整定的依据.

  14. How adaptable is the hydraulic system of European beech in the face of climate change-related precipitation reduction?

    Schuldt, Bernhard; Knutzen, Florian; Delzon, Sylvain; Jansen, Steven; Müller-Haubold, Hilmar; Burlett, Régis; Clough, Yann; Leuschner, Christoph


    Climate warming will increase the drought exposure of many forests world-wide. It is not well understood how trees adapt their hydraulic architecture to a long-term decrease in water availability. We examined 23 traits characterizing the hydraulic architecture and growth rate of branches and the dependent foliage of mature European beech (Fagus sylvatica) trees along a precipitation gradient (855-594 mm yr(-1) ) on uniform soil. A main goal was to identify traits that are associated with xylem efficiency, safety and growth. Our data demonstrate for the first time a linear increase in embolism resistance with climatic aridity (by 10%) across populations within a species. Simultaneously, vessel diameter declined by 7% and pit membrane thickness (Tm ) increased by 15%. Although specific conductivity did not change, leaf-specific conductivity declined by 40% with decreasing precipitation. Of eight plant traits commonly associated with embolism resistance, only vessel density in combination with pathway redundancy and Tm were related. We did not confirm the widely assumed trade-off between xylem safety and efficiency but obtained evidence in support of a positive relationship between hydraulic efficiency and growth. We conclude that the branch hydraulic system of beech has a distinct adaptive potential to respond to a precipitation reduction as a result of the environmental control of embolism resistance.

  15. Hydraulic system of traction bed for maintenance%牵引床液压系统的故障维修



    Neck lumbar traction bed is through the computer control motor and hydraulic transmission device, implementation of traditional Chinese medicine traction, Angle rotation and manual reduction action of a device, etc. Saving time and effort can well meet the needs of the treatment on lumbar disease. Based on the failure phenomenon of traction bed hydraulic transmission device, the composition and working principle analysis of the hydraulic system, concluded that failure of the hydraulic transmission device is due to the pressure gauge damaged or blocked between the tubing and the overflow valve, which allows users to quickly troubleshoot.%颈腰椎牵引床是通过计算机控制电机和液压传动装置,实现中医牵引、角度转动及手法复位等动作的治疗设备。该设备省时省力,能较好地满足治疗腰椎疾病的需要。根据牵引床液压传动装置出现的故障现象,分析液压系统的组成及其工作原理,判断造成液压传动装置的故障是由于压力表损坏或出油管与溢流阀之间的堵塞而引起,从而快捷地排除故障。


    Yao Jianjun; Wu Zhenshun; Han Junwei; Yue Donghai


    The method for harmonic cancellation based on artificial neural network (ANN) is proposed. The task is accomplished by generating reference signal with frequency that should be eliminated from the output. The reference input is weighted by the ANN in such a way that it closely matches the harmonic. The weighted reference signal is added to the fundamental signal such that the output harmonic is cancelled leaving the desired signal alone. The weights of ANN are adjusted by output harmonic, which is isolated by a bandpass filter. The above concept is used as a basis for the development of adaptive harmonic cancellation (AHC) algorithm. Simulation results performed with a hydraulic system demonstrate the efficiency and validity of the proposed AHC control scheme.


    WONG Pak-kin; TAM Lap-mou; LI Ke


    In modern four-stroke engine technology, variable valve timing and lift control offers potential benefits for making a high-performance engine. A novel electro-hydraulic fully variable valve train for four-stroke automotive engines is introduced. The construction of the nonlinear mathematic model of the valve train system and its dynamic analysis are also presented. Experimental and simulation results show that the novel electro-hydraulic valve train can achieve fully variable valve timing and lift control. Consequently the engine performance on different loads and speeds will be significantly increased. The technology also permits the elimination of the traditional throttle valve in the gasoline engines and increases engine design flexibility.

  18. A study of passive and adaptive hydraulic engine mount systems with emphasis on non-linear characteristics

    Kim, G.; Singh, R.


    Passive hydraulic mounts exhibit excitation frequency variant and deflection amplitude sensitive stiffness and damping properties. Such non-linear dynamic characteristics are examined by using analytical and experimental methods, both at the device level and within the context of a simplified vehicle model. A new lumped parameter non-linear mathematical model of the hydraulic mount is developed by simulating its decoupler switching mechanism and inertia track dynamics. The low frequency performance features and limitations of several passive mounts are made clear through the non-linear vehicle model simulation and comparable laboratory vibration tests. The high frequency performance problems of the passive hydraulic mount are identified by applying the quasi-linear analysis method. Based on these results, a new adaptive mount system is developed which exhibits broad bandwidth performance features up to 250 Hz. It implements an on-off damping control mode by using engine intake manifold vacuum and a microprocessor based solenoid valve controller. A laboratory bench set-up has already demonstrated its operational feasibility. Through analytical methods, it is observed that our adaptive mount provides superior dynamic performance to passive engine mounts and comparable performance to a small scale active mount over a wide frequency range, given the engine mounting resonance control, shock absorption and vibration isolation performance requirements. Although technical prospects of the proposed adaptive system appear promising, the in situperformance needs to be evaluated.

  19. Research and application of coal and gas outburst control measure based on hydraulic extrusion in roadway

    Liu, M.; Pan, H.; Li, Y.; Hu, B.; Chen, W. [Henan Polytechnic University, Jiaozuo (China)


    The technology system and equipment of hydraulic extrusion were presented. Based on the actual conditions of Liyi Coal Mine, reasonable parameters of injecting water were studied. The measure caused the stress concentration region of the coal seam to move forward, the pressure relief region was widened, and gas was released efficiently. The remarkable effect of coal and gas outburst prevention was achieved and the roadway driving speed was increased by 1.5 times. 7 refs., 5 figs.

  20. Hydraulic High Pressure Valve Controller Using the In-Situ Pressure Difference

    Bao, Xiaoqi (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor); Hall, Jeffery L. (Inventor)


    A hydraulic valve controller that uses an existing pressure differential as some or all of the power source for valve operation. In a high pressure environment, such as downhole in an oil or gas well, the pressure differential between the inside of a pipe and the outside of the pipe may be adequately large to drive a linear slide valve. The valve is operated hydraulically by a piston in a bore. When a higher pressure is applied to one end of the bore and a lower pressure to the other end, the piston moves in response to the pressure differential and drives a valve attached to it. If the pressure differential is too small to drive the piston at a sufficiently high speed, a pump is provided to generate a larger pressure differential to be applied. The apparatus is conveniently constructed using multiport valves, which can be rotary valves.

  1. Design of Electro-hydraulic Closed-loop Control System and Environmental Adaptability Verification%电液闭环控制系统设计和环境适应性验证

    李向阳; 吴林瑞; 李文书; 许进亮


    发射车控制系统对环境适应性差,针对这一情况,提出压力闭环控制和角速度闭环控制策略,并在发射车上经过试验验证,表明闭环控制策略能有效地改进发射车控制系统的环境适应性.%Based on the analysis of poor environmental adaptability of launcher control system, pressure closed-loop control and angular velocity closed-loop control strategies were proposed and were verified on the launcher which showed that closed-loop control strategy can improve the environmental adaptability of launcher control system effectively.

  2. Realization of tin freezing point using a loop heat pipe-based hydraulic temperature control technique

    Joung, Wukchul; Gam, Kee Sool; Kim, Yong-Gyoo


    In this work, the freezing point of tin (Sn FP) was realized by inside nucleation where the supercooling of tin and the reheating of the sample after the nucleation were achieved without extracting the cell from an isothermal apparatus. To this end, a novel hydraulic temperature control technique, which was based on the thermo-hydraulic characteristics of a pressure-controlled loop heat pipe (LHP), was employed to provide a slow cooling of the sample for deep supercooling and fast reheating after nucleation to minimize the amount of initial freeze of the sample. The required temperature controls were achieved by the active pressure control of a control gas inside the compensation chamber of the pressure-controlled LHP, and slow cooling at  -0.05 K min-1 for the deep supercooling of tin and fast heating at 2 K min-1 for reheating the sample after nucleation was attained. Based on this hydraulic temperature control technique, the nucleation of tin was realized at supercooling of around 19 K, and a satisfactorily fast reheating of the sample to the plateau-producing temperature (i.e. 0.5 K below the Sn FP) was achieved without any temperature overshoots of the isothermal region. The inside-nucleated Sn FP showed many desirable features compared to the Sn FP realized by the conventional outside nucleation method. The longer freezing plateaus and the better immersion characteristics of the Sn FP were obtained by inside nucleation, and the measured freezing temperature of the inside-nucleated Sn FP was as much as 0.37 mK higher than the outside-nucleated Sn FP with an expanded uncertainty of 0.19 mK. Details on the experiment are provided and explanations for the observed differences are discussed.

  3. Hydraulics and pneumatics

    Parr, Andrew


    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. This is frequently accomplished by means of electrical equipment (such as motors or solenoids), or via devices driven by air (pneumatics) or liquids (hydraulics).This book has been written by a process control engineer as a guide to the operation of hydraulic and pneumatic systems for all engineers and technicians who wish to have an insight into the components and operation of such a system.This second edition has been fully updated to include all recent developments su

  4. Improving the Hydraulic Performance of Stormwater Infiltration Systems in Clay Tills

    Bockhorn, Britta

    D study was initiated with the objective to test and evaluate if the hydraulic performance of stormwater infiltration systems can be significantly improved if the site-specific geological heterogeneity is incorporated into the design and siting of such systems. The assessment is based on different field...... infiltration systems. Models employing standard soil physical parameters should be used with care as they do not always realistically describe site-specific hydrologic properties. A fourth study showed that the hydraulic performance of infiltration trenches was increased by a factor of two, when spear auger......Many cities of the Northern Hemisphere are covered by low permeable clay tills, which pose a challenge for stormwater infiltration practices. However, clay tills are amongst the most heterogeneous types of sediments and hydraulic conductivities can vary by several orders of magnitude. This Ph...

  5. Application of second order sliding mode algorithms for output feedback control in hydraulic cylinder drives with profound valve dynamics

    Schmidt, Lasse; Andersen, Torben O.


    consideration are applied for position tracking control of a hydraulic valve-cylinder drive exhibiting strong variations in inertia- and gravitational loads, and furthermore suffer from profound valve dynamics. Results demonstrate that both the twisting- and super twisting algorithms may be successfully applied......The application of second order sliding mode algorithms for output feedback control in hydraulic valve-cylinder drives appear attractive due to their simple realization and parametrization, and strong robustness toward bounded parameter variations and uncertainties. However, intrinsic nonlinear...

  6. Analysis of the steady state hydraulic behaviour of the ITER blanket cooling system

    Di Maio, P.A., E-mail: [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Dell’Orco, G.; Furmanek, A. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Garitta, S. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Merola, M.; Mitteau, R.; Raffray, R. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Spagnuolo, G.A.; Vallone, E. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy)


    Highlights: • Nominal steady state hydraulic behaviour of ITER blanket standard sector cooling system has been investigated. • Numerical simulations have been run adopting a qualified thermal-hydraulic system code. • Hydraulic characteristic functions and coolant mass flow rates, velocities and pressure drops have been assessed. • Most of the considered circuits are able to effectively cool blanket modules, meeting ITER requirements. - Abstract: The blanket system is the ITER reactor component devoted to providing a physical boundary for plasma transients and contributing to thermal and nuclear shielding of vacuum vessel, magnets and external components. It is expected to be subjected to significant heat loads under nominal conditions and its cooling system has to ensure an adequate cooling, preventing any risk of critical heat flux occurrence while complying with pressure drop limits. At the University of Palermo a study has been performed, in cooperation with the ITER Organization, to investigate the steady state hydraulic behaviour of the ITER blanket standard sector cooling system. A theoretical–computational approach based on the finite volume method has been followed, adopting the RELAP5 system code. Finite volume models of the most critical blanket cooling circuits have been set-up, realistically simulating the coolant flow domain. The steady state hydraulic behaviour of each cooling circuit has been investigated, determining its hydraulic characteristic function and assessing the spatial distribution of coolant mass flow rates, velocities and pressure drops under reference nominal conditions. Results obtained have indicated that the investigated cooling circuits are able to provide an effective cooling to blanket modules, generally meeting ITER requirements in term of pressure drop and velocity distribution, except for a couple of circuits that are being revised.

  7. Permeability Enhancement in Enhanced Geothermal System as a result of Hydraulic Fracturing and Jacking

    Jalali, Mohammadreza; Klepikova, Maria; Fisch, Hansruedi; Amann, Florian; Loew, Simon


    A decameter-scale in-situ hydraulic stimulation and circulation (ISC) experiment has been initiated by the newly-founded Swiss Competence Centre for Energy Research - Supply of Electricity (SCCER-SoE) at Nagra's Grimsel Test Site (GTS) as a part of the work-package WP1 of the Deep Underground Laboratory (DUG-Lab) initiative. The experiment area is situated in the southern part of the GTS in a low fracture density volume of the Grimsel granodiorite. The hydraulic properties of the granitic rock mass are supposed to be similar to those expected in the crystalline basement of the alpine foreland where deep enhanced geothermal systems might be developed in future. The main objectives of the multi-disciplinary experiment are to provide a high resolution pre- and post-stimulation characterization of fracture permeability and connectivity, to investigate patterns of preferential flow paths, to describe the pressure propagation during the stimulation phases and to evaluate the efficiency of the fracture-matrix heat exchanger. A comprehensive test & monitoring layout including a fair number of boreholes instrumented with a variety of sensors (e.g. pressure, strain, displacement, temperature, and seismic sensors) is designed to collect detailed data during multiple hydraulic stimulation runs. The diffusion of fluid pressure is expected to be governed mainly by the properties and geometry of the existent fracture network. The hydraulic transmissivity of fractures are in the range of 10-7 to 10-9 m2/s whereas the matrix rock has a very low hydraulic conductivity (K ˜ 10-12 m/s). As part of the stress measurement campaign during the pre-stimulation phase of the ISC experiment, a series of hydraulic fracturing (HF) and hydraulic tests in pre-existing fractures (HTPF) were conducted. The tests were accompanied by micro-seismic monitoring within several observation boreholes to investigate the initiation and propagation of the induced fractures. Together with results from over

  8. Mathematic Modeling of Complex Hydraulic Machinery Systems When Evaluating Reliability Using Graph Theory

    Zemenkova, M. Yu; Shipovalov, A. N.; Zemenkov, Yu D.


    The main technological equipment of pipeline transport of hydrocarbons are hydraulic machines. During transportation of oil mainly used of centrifugal pumps, designed to work in the “pumping station-pipeline” system. Composition of a standard pumping station consists of several pumps, complex hydraulic piping. The authors have developed a set of models and algorithms for calculating system reliability of pumps. It is based on the theory of reliability. As an example, considered one of the estimation methods with the application of graph theory.

  9. Fault Diagnosis for Nonlinear Hydraulic-Mechanical Drilling Pipe Handling System

    Choux, Martin; Blanke, Mogens


    Leakage and increased friction are common faults in hydraulic cylinders that can have serious consequences if they are not detected at early stage. In this paper, the design of a fault detector for a nonlinear hydraulic mechanical system is presented. By considering the system in steady state, two...... residual signals are generated and analysed with a composite hypothesis test which accommodates for unknown parameters. The resulting detector is able to detect abrupt changes in leakage or friction given the noisy pressure and position measurements. Test rig measurements validate the properties...

  10. Program control of edge pressing system for sheet metal forming hydraulic press%薄板成形液压机压边系统的程序控制

    魏湘; 陆红; 李秀珠


    A programmable hydraulic deep drawing edge pressing design has been introduced in the text. By regulating the output pressure of four-corner edge pressing cylinder via program, the reasonable flowing deformation has been occurred to the plastic sheet metal. Thus in this way, the hydraulic press realizes the follow-up regulation of the deep drawing technology. It suits for the manufacture of the modern automotive and aviation industry sheet metal. It can improve the deep drawing technology greatly.%介绍了一种可编程的液压拉深压边设计.以程序调控四角压边缸的输出压力,使塑性金属板料进行合理“流变”,从而赋予液压机实现拉深成形工艺的随动调控.

  11. Comparison of System Identification Techniques for the Hydraulic Manipulator Test Bed (HMTB)

    Morris, A. Terry


    In this thesis linear, dynamic, multivariable state-space models for three joints of the ground-based Hydraulic Manipulator Test Bed (HMTB) are identified. HMTB, housed at the NASA Langley Research Center, is a ground-based version of the Dexterous Orbital Servicing System (DOSS), a representative space station manipulator. The dynamic models of the HMTB manipulator will first be estimated by applying nonparametric identification methods to determine each joint's response characteristics using various input excitations. These excitations include sum of sinusoids, pseudorandom binary sequences (PRBS), bipolar ramping pulses, and chirp input signals. Next, two different parametric system identification techniques will be applied to identify the best dynamical description of the joints. The manipulator is localized about a representative space station orbital replacement unit (ORU) task allowing the use of linear system identification methods. Comparisons, observations, and results of both parametric system identification techniques are discussed. The thesis concludes by proposing a model reference control system to aid in astronaut ground tests. This approach would allow the identified models to mimic on-orbit dynamic characteristics of the actual flight manipulator thus providing astronauts with realistic on-orbit responses to perform space station tasks in a ground-based environment.

  12. Discrete Displacement Hydraulic Power Take-Off System for the Wavestar Wave Energy Converter

    Hansen, Rico Hjerm; Kramer, Morten; Vidal, Enrique


    is converted into electricity at a steady pace by hydraulic motors and generators. The storage, thereby, decouples the complicated process of wave power absorption from power generation. The core for enabling this PTO technology is implementing a near loss-free force control of the energy absorbing cylinders...

  13. Thermal Equilibrium Analysis of Hydraulic System%液压系统热平衡分析



    For hydraulic system due to the ageing of the equipment caused to the system temperature is too high,don’t adopt the traditional method,for the heat generated by the power loss and heat coming from the system to calculate,but only for the Newly added heat of the hydraulic system for testing,calculation.Select the corre-sponding cooling mode,the hydraulic system is maintained at the set temperature range.When QAbsorption is equal to QRelease ,the new thermal balance of hydraulic system is realized.%针对液压系统因设备老化而造成的系统温度过高,传统的方法采用对功率损耗产生的热量与系统散发的热量进行计算,而本文是仅对液压系统的新增热量进行测试、计算。选择相对应的冷却方式,使液压系统保持在设定的温度范围内,当Q吸=Q放时,即实现了液压系统新的热平衡。

  14. Hydraulics and pneumatics a technician's and engineer's guide

    Parr, Andrew


    Hydraulics and Pneumatics: A Technician's and Engineer's Guide provides an introduction to the components and operation of a hydraulic or pneumatic system. This book discusses the main advantages and disadvantages of pneumatic or hydraulic systems.Organized into eight chapters, this book begins with an overview of industrial prime movers. This text then examines the three different types of positive displacement pump used in hydraulic systems, namely, gear pumps, vane pumps, and piston pumps. Other chapters consider the pressure in a hydraulic system, which can be quickly and easily controlled

  15. Research on a Nonlinear Robust Adaptive Control Method of the Elbow Joint of a Seven-Function Hydraulic Manipulator Based on Double-Screw-Pair Transmission

    Gaosheng Luo


    Full Text Available A robust adaptive control method with full-state feedback is proposed based on the fact that the elbow joint of a seven-function hydraulic manipulator with double-screw-pair transmission features the following control characteristics: a strongly nonlinear hydraulic system, parameter uncertainties susceptible to temperature and pressure changes of the external environment, and unknown outer disturbances. Combined with the design method of the back-stepping controller, the asymptotic stability of the control system in the presence of disturbances from uncertain systematic parameters and unknown external disturbances was demonstrated using Lyapunov stability theory. Based on the elbow joint of the seven-function master-slave hydraulic manipulator for the 4500 m Deep-Sea Working System as the research subject, a comparative study was conducted using the control method presented in this paper for unknown external disturbances. Simulations and experiments of different unknown outer disturbances showed that (1 the proposed controller could robustly track the desired reference trajectory with satisfactory dynamic performance and steady accuracy and that (2 the modified parameter adaptive laws could also guarantee that the estimated parameters are bounded.

  16. Study of the performance of four repairing material systems for hydraulic structures of concrete dams

    Kormann A. C. M.


    Full Text Available Four types of repairing materials are studied as function of either a conventional concrete or a reference-concrete (RefC, these are: polymer-modified cement mortar (PMor, steel fiber concrete (SFco, epoxy mortar (EMor and silica fume mortar (SFmo, to be applied in hydraulic structures surfaces subjected to a high velocity water flow. Besides the mechanical requests and wearing resistance of hydraulic concrete dam structures, especially the spillway surfaces, the high solar radiation, the environmental temperature and wet and dry cycles, contribute significantly to the reduction of their lifespan. RefC and the SFco were developed based on a usual concrete mixture used in slabs of spillways. The average RefC mixture used was 1: 1.61: 2.99: 0.376, with Pozzolan-modified Portland cement consumption of 425 kg/m³. EMor and PMor mixtures followed the information given by the manufacturers and lab experience. Tests on concrete samples were carried out in laboratory simulating normally found environmental situations in order to control the mechanical resistance and the aging imposed conditions, such as solar radiation and humidity. Also, physicochemical characterizing tests were made for all used materials. From the analyzed results, two of them presented a higher performance: the EMor and SFmo. SFco presented good adherence to the RefC and good mechanical performance. However, it also presented apparent metal corrosion in humidity tests, being indicated for use, with caution, as an intermediate layer in underwater repairs. In a general classification, considering all tests, including their field applications, the better performance material systems were EMor- SFmo> SFco> PMor.

  17. Design and Development of Hydraulic Disc Brake Systems for Well Servicing Rig Drawworks

    Gao xiangqian; Zhou Yongxia


    @@ The conventional band brakes have been known to be important but also the most unlnerable part in servicing rig deawworks.. The failures in braking and releasing operations haven't well been avoided. There have evidently existed the problems of difficult operation and inconvenient maintenance in this connection. The use of power-assisted hydraulic cylinders or pneumatic cylinders can not meet the requirements of operations either. Since the late 1980s, we have cooperated with Shengli oilfields and others in the successful design and development of PST25 hydraulic disc brake systems for well servicing rig in a fully closed working state.


    A. Ja. Kotlobai


    Full Text Available Operational efficiency of multi-functional road construction machines depends on number of working bodies which are simultaneously performing technological operations. Systems for propulsion pto to the running equipment drive and active working bodies of road construction machines are developing in the way of using three-axis hydraulic drives. When designing a hydraulic system for road construction machinery dividing of power flow from propulsion to the running equipment drive and active working bodies is considered as rather essential problem. Leading companies do not pay attention to the development of flow divider designs, preferring to produce more expensive multi-flow pumps. One of the ways to increase efficiency of multi-functional road construction machinery is an implementation of running equipment hydraulic driving system based on a mono-aggregate pump unit which consists of a pump and a volumetric divider of power fluid flow. A principle of volumetric division and summing-up of power fluid flows, technical realization and methodology for calculation of key parameters of discrete flow distributors has been developed on the basis of discrete hydraulics regulations. The paper presents results of mathematical modeling of hydraulic systems equipped with the discrete flow distributor. Analysis of a dual-motor hydraulic drive operation has shown the following results: a discrete flow distributor ensures independent load mode of the current consumer circuit operation from the load mode of the second consumer circuit within a wide range of loads; rational value of working fluid flow discretization parameter is the following value interval k = 4–6, maximum value of parameter efficiency is reached when an angular velocity of a distributor rotor coincides with the angular velocity of a pump shaft; discrete flow distributor provides a possibility to change parameters of hydraulic flow feeding in consumers’ pressure lines within a wide range

  19. High Resolution Hydraulic Profiling and Groundwater Sampling using FLUTe™ System in a Fractured Limestone Setting

    Janniche, Gry Sander; Christensen, Anders G.; Grosen, Bernt;

    innovative investi-gation methods for characterization of the source zone hydrogeology and contamination, including FLUTe system hydraulic profiling and Water-FLUTe multilevel groundwater sampling, in fractured bryo-zoan limestone bedrock. High resolution hydraulic profiling was conducted in three cored......Characterization of the contaminant source zone architecture and the hydraulics is essential to develop accurate site specific conceptual models, delineate and quantify contaminant mass, perform risk as-sessment, and select and design remediation alternatives. This characterization is particularly...... challeng-ing in deposit types as fractured limestone. The activities of a bulk distribution facility for perchloroe-thene (PCE) and trichloroethene (TCE) at the Naverland site near Copenhagen, Denmark, has resulted in PCE and TCE DNAPL impacts to a fractured clay till and an underlying fractured limestone...

  20. Aircraft Fuel, Hydraulic and Pneumatic Systems (Course Outlines), Aviation Mechanics 3 (Air Frame): 9067.01.

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to familiarize the student with the operation, inspection, and repair of aircraft fuel, hydraulic, and pneumatic systems. It is designed to help the trainee master the knowledge and skills necessary to become an aviation airframe mechanic. The aviation airframe maintenance technician…

  1. Design of Hydraulic Generator Cooling Fan Frequency Conversion Control System%水轮发电机冷却风机变频控制系统的设计


      讲述基于PLC的PID控制算法的水轮发电机冷却风机变频控制系统。系统主要应用于灯泡贯流式水轮发电机组,使得灯泡贯流机组冷却温度恰当,既节能又兼顾发电效率和发电机寿命。%This paper describes the PID control algorithm of PLC based turbine generator cooling fan frequency conversion control system. The system is mainly used for bulb turbine unit,the bulb tubular units appropriate cooling temperature,energy saving,power generation efficiency and service life of the generator.

  2. Study on maximum power control of turbines in a tidal current power generation system based on hydraulic transmission%液压型潮流能发电系统叶轮最大功率控制

    林躜; 李磊; 陈俊华; 郑堤; 唐辰; 李浩


    In order to solve the problem of low energy capturing efficiency of the horizontal axis turbine in tidal current power generation system at low current speed, a variable pump counter torque reference value model was established. In this study, based on the maximum power tracking theory and the torque equilibrium equation of turbine versus variable pump, a control system with indirect speed control, pressure feedback, and torque control was designed to achieve the maximum power capture of the turbine by regulating the output of the variable pump in a small range. The performance of the designed control system was simulated by means of the Automation Studio software, and corresponding sea test was conducted. Test results showed that the control system ran steadily, the captured power coefficient of the turbine fluctuated near 0.35 and 0.33, respectively, in the simulation and sea trials; compared with the uncontrolled, these numbers increased by 0.03 and 0.05, respectively. The capture efficiency of the turbine was enhanced, and the effectiveness of the control system was verified.%文章为解决水平轴潮流能发电系统在低于设计流速下叶轮能量捕获效率低的问题,运用最大功率跟踪控制理论及叶轮与变量泵传动轴力矩平衡方程,建立了变量泵反力矩参考值模型,设计了间接速度控制的压力反馈加转矩控制系统,通过小范围内调节变量泵排量,实现叶轮最大功率捕获。整个系统的性能在自动化工作室(automation studio)中进行了仿真测试,实验样机也进行了海上试验。仿真测试和海试结果显示,该控制系统工作稳定性好,仿真和海试时叶轮的捕获功率系数分别在0.35和0.33附近波动,相比不加控制,分别增加了约0.03和0.05,提高了叶轮的捕获效率,验证了控制系统的有效性。

  3. Simulating AGC Hydraulic System of Single-stand Cold Rolling Mill%单机架冷轧机 AGC 液压系统仿真

    吴中友; 陈举庆


    Hopsan Hydraulic Simulation software is used to model and simulate AGC hydraulic system of a 1250mm single-stand cold rolling mill to compare the difference and connection between the position loop and force loop of the control system. With this simulation, the factor that effects the function of AGC hydraulic systems can be analyzed.%  采用 Hopsan 液压仿真软件对某1250 mm 单机架可逆冷轧机 AGC 液压系统建模仿真,比较位置环与力环控制系统的差异和联系,对影响 AGC 液压系统性能的因素进行分析。

  4. Multi-physics Coupling of Hydraulic System%液压系统多场耦合

    张健; 罗念宁; 姜继海


    概述了液压系统多物理场耦合问题,介绍了各种耦合关系的分类方法以及液压系统中所涉及的主要物理场,并介绍了液压系统多场耦合问题的国内外研究现状.针对液压系统中常见的热、气穴、压力与流量脉动问题,分析了这些常见问题主要受到了哪些物理场的影响,并简要介绍了这些问题中存在的多物理场耦合现象,对这些问题的研究趋势进行了预测,指出在日后的研究工作中应建立多场耦合问题数学模型.最后提出了针对液压系统多场耦合特性的研究方法.%In this paper,a summary of multi-physics coupling of hydraulic system is given.The paper introduces the taxonomy of various coupling relationship and the mainly physics fields in the hydraulic system.And this paper introduces a summary of multi-physics coupling of hydraulic system both within China and abroad.According to some common problems of thermal,cavitation,pressure ripple and flow ripple on hydraulic system,this paper analyzes which fields influence on these problems,and briefly introduces the existing multi-physics coupling phenomena of problems.This paper predicts the research trend of these problems,and points out that the mathematical model of multi-physics coupling needs to be established in the future research work.studies on the mainly physics fields are involved in hydraulic system when these problems influence hydraulic system.Finally,this paper puts forward the research method of multi-physics coupling of hydraulic system.

  5. Theoretical Analysis and Bench Tests of a Control-Surface Booster Employing a Variable Displacement Hydraulic Pump

    Mathews, Charles W.; Kleckner, Harold F.


    The NACA is conducting a general investigation of servo-mechanisms for use in powering aircraft control surfaces. This paper presents a theoretical analysis and the results of bench tests of a control-booster system which employs a variable displacement hydraulic pump. The booster is intended for use in a flight investigation to determine the effects of various booster parameters on the handling qualities of airplanes. Such a flight investigation would aid in formulating specific requirements concerning the design of control boosters in general. Results of the theoretical analysis and the bench tests indicate that the subject booster is representative of types which show promise of satisfactory performance. The bench tests showed that the following desirable features were inherent in this booster system: (1) No lost motion or play in any part of the system; (2) no detectable lag between motion of the contra1 stick and control surface; and (3) Good agreement between control displacements and stick-force variations with no hysteresis in the stick-force characteristics. The final design configuration of this booster system showed no tendency to oscillate, overshoot, or have other undesirable transient characteristics common to boosters.

  6. 中央空调冷冻水系统的水力平衡调试%Hydraulic balance debugging of central air-conditioning chilled water system



    在管道系统中增设静态、动态水力平衡设备是解决管路的水力失调的常用方法,而系统的水力平衡调试也成为空调系统调试的重要内容之一。本文介绍了空调水系统水力平衡的调试方法,并结合工程实例,着重说明通过流量比例调节法进行静态水力平衡的原理及过程。%Addition of static and dynamic hydraulic balance equipment in the pipeline system is the common method to solve the imbalance of hydraulic pipeline , and the hydraulic balance system debugging has become one of the important contents of the air conditioning system debugging .This paper introduces the debugging method of hydraulic balance of air conditioning water system , and combined with the engi-neering practice , emphasizes the principle and process of static hydraulic balancing by the flow ratio control method .

  7. Modeling and Optimal Design of 3 Degrees of Freedom Helmholtz Resonator in Hydraulic System

    GUAN Changbin; JIAO Zongxia


    Three degrees of freedom (3-DOF) Helmholtz resonator which consists of three cylindrical necks and cavities connected in series (neck-cavity-ncck-cavity-neck-cavity) is suitable to reduce flow pulsation in hydraulic system.A novel lumped parameter model (LPM) of 3-DOF Helmholtz resonator in hydraulic system is developed which considers the viscous friction loss of hydraulic fluid in the necks.Applying the Newton's second law of motion to the equivalent mechanical model of the resonator,closed-form expression of transmission loss and resonance frequency is presented.Based on the LPM,an optimal design method which employs rotate vector optimization method (RVOM) is proposed.The purpose of the optimal design is to search the resonator's unknown parameters so that its resonance frequencies can coincide with the pump-induced flow pulsation harmonics respectively.The optimal design method is realized to design 3-DOF Helmholtz resonator for a certain type of aviation piston pump hydraulic system.The optimization result shows the feasibility of this method,and the simulation under optimum parameters reveals that the LPM can get the same precision as transfer matrix method (TMM).

  8. Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System

    Robert C. O' Brien; Andrew C. Klein; William T. Taitano; Justice Gibson; Brian Myers; Steven D. Howe


    Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study validate the feasibility of a practical thermally capacitive RTR propulsion system.

  9. Benchmarking of Advanced Control Strategies for a Simulated Hydroelectric System

    Finotti, S.; Simani, S.; Alvisi, S.; Venturini, M.


    This paper analyses and develops the design of advanced control strategies for a typical hydroelectric plant during unsteady conditions, performed in the Matlab and Simulink environments. The hydraulic system consists of a high water head and a long penstock with upstream and downstream surge tanks, and is equipped with a Francis turbine. The nonlinear characteristics of hydraulic turbine and the inelastic water hammer effects were considered to calculate and simulate the hydraulic transients. With reference to the control solutions addressed in this work, the proposed methodologies rely on data-driven and model-based approaches applied to the system under monitoring. Extensive simulations and comparisons serve to determine the best solution for the development of the most effective, robust and reliable control tool when applied to the considered hydraulic system.

  10. A practical nonlinear robust control approach of electro-hydraulic load simulator

    Wang Chengwen; Jiao Zongxia; Wu Shuai; Shang Yaoxing


    This paper studies a nonlinear robust control algorithm of the electro-hydraulic load simulator (EHLS). The tracking performance of the EHLS is mainly limited by the actuator’s motion disturbance, flow nonlinearity, and friction, etc. The developed controller is developed based on the nonlinear motion loading model. The problems of the actuator’s disturbance and flow nonlinearity are considered. To address the friction problem, the friction model of the loading motor is identified experimentally. The friction disturbance is compensated using the obtained friction model. Therefore, this paper considers the main three factors comprehensively. The devel-oped algorithm is easy to apply since the controller can be obtained just with one step back-stepping design. The stability of the developed algorithm is proven via Lyapunov analysis. Both co-simula-tion and experiments are performed to verify the effectiveness of this method.

  11. Hydraulic Actuators with Autonomous Hydraulic Supply for the Mainline Aircrafts

    I. S. Shumilov


    Full Text Available Applied in the aircraft control systems, hydraulic servo actuators with autonomous hydraulic supply, so-called, hydraulic actuators of integrated configuration, i.e. combination of a source of hydraulic power and its load in the single unit, are aimed at increasing control system reliability both owing to elimination of the pipelines connecting the actuator to the hydraulic supply source, and owing to avoidance of influence of other loads failure on the actuator operability. Their purpose is also to raise control system survivability by eliminating the long pipeline communications and their replacing for the electro-conductive power supply system, thus reducing the vulnerability of systems. The main reason for a delayed application of the hydraulic actuators in the cutting-edge aircrafts was that such aircrafts require hydraulic actuators of considerably higher power with considerable heat releases, which caused an unacceptable overheat of the hydraulic actuators. Positive and negative sides of the hydraulic actuators, their alternative options of increased reliability and survivability, local hydraulic systems as an advanced alternative to independent hydraulic actuators are considered.Now to use hydraulic actuators in mainline aircrafts is inexpedient since there are the unfairly large number of the problems reducing, first and last, safety of flights, with no essential weight and operational advantages. Still works to create competitive hydraulic actuators ought to be continued.Application of local hydraulic systems (LHS will allow us to reduce length of pressure head and drain pipelines and mass of pipelines, as well as to raise their general fail-safety and survivability. Application of the LHS principle will allow us to use a majority of steering drive advantages. It is necessary to allocate especially the following:- ease of meeting requirements for the non-local spread of the engine weight;- essentially reducing length and weight of

  12. 10MN/16MN数控高性能拉深液压机液压系统研究%Study on hydraulic system of 10MN/16MN high performance deep-drawing hydraulic press

    叶臻; 王晋抚


    介绍了提高双动拉深液压机高性能的关键液压技术.分析了影响液压机快速平稳运行和压边滑块四角调平的原因,并对其液压回路分别进行了研究.解决了双动液压机速度慢和精度低等技术难题,有效提高了生产频率和综合性能.%The key technology for improving the high performance of deep-drawing hydraulic press has been introduced in the text. The reasons for influence of fast and smooth running of hydraulic press and four corners leveling control system for blank slider have been analyzed, and the hydraulic loops have been studied. Finally, the technical problems such as slow speed and low accuracy of double action hydraulic press have been solved, which effectively raise the production rate and comprehensive performance.

  13. Handbook of hydraulic fluid technology

    Totten, George E


    ""The Handbook of Hydraulic Fluid Technology"" serves as the foremost resource for designing hydraulic systems and for selecting hydraulic fluids used in engineering applications. Featuring new illustrations, data tables, as well as practical examples, this second edition is updated with essential information on the latest hydraulic fluids and testing methods. The detailed text facilitates unparalleled understanding of the total hydraulic system, including important hardware, fluid properties, and hydraulic lubricants. Written by worldwide experts, the book also offers a rigorous overview of h

  14. A Hydraulic Motor-Alternator System for Ocean-Submersible Vehicles

    Aintablian, Harry O.; Valdez, Thomas I.; Jones, Jack A.


    An ocean-submersible vehicle has been developed at JPL that moves back and forth between sea level and a depth of a few hundred meters. A liquid volumetric change at a pressure of 70 bars is created by means of thermal phase change. During vehicle ascent, the phase-change material (PCM) is melted by the circulation of warm water and thus pressure is increased. During vehicle descent, the PCM is cooled resulting in reduced pressure. This pressure change is used to generate electric power by means of a hydraulic pump that drives a permanent magnet (PM) alternator. The output energy of the alternator is stored in a rechargeable battery that powers an on-board computer, instrumentation and other peripherals.The focus of this paper is the performance evaluation of a specific hydraulic motor-alternator system. Experimental and theoretical efficiency data of the hydraulic motor and the alternator are presented. The results are used to evaluate the optimization of the hydraulic motor-alternator system. The integrated submersible vehicle was successfully operated in the Pacific Ocean near Hawaii. A brief overview of the actual test results is presented.

  15. 热连轧液压活套综合控制策略%Integrated control strategies of hydraulic loop for hot strip mill



    Under the background of the hydraulic loop system for the finishing mill in hot strip mill of Ansteel,the control principle and production process of hydraulic loop are analyzed in detail,moreover length of loop for hydraulic loop system and mathematical models of torque are derived. Furthermore, integrated control strategies and algorithms of hydraulic loop are put forward. Field application shows that the strategies and algorithms have strong adaptability,loop system is of stable operation,and hy-draulic loop has the advantages of low inertia and quick responses,which is laying a solid foundation for the realization of quality targets such as the thickness,shape and width.%以鞍钢集团某1700热连轧生产线精轧机组的液压活套系统为背景,对液压活套生产工艺过程和控制原理进行了详细分析,推导出液压活套套量及力矩数学模型,提出了液压活套综合控制策略和算法。实际应用表明该控制策略和算法具有较强的适应性,活套系统运行稳定,发挥了液压活套的惯性小、响应快等优点,为保证厚度、板形和宽度等质量指标的实现奠定了基础。

  16. Chapter 13. Industrial Application of Tap Water Hydraulic Systems

    Conrad, Finn; Adelstorp, Anders


    Design and application of modern pure tap water components and systems in industries, in particular food processing industry.......Design and application of modern pure tap water components and systems in industries, in particular food processing industry....

  17. Experimental studies on dynamic system characteristics of the high temperature/high pressure thermal-hydraulic test facility(VISTA) for the power variation

    Choi, K. Y.; Park, H. S.; Joe, S.; Park, C. K.; Lee, S. J.; Song, C. W.; Jeong, M. K. [KAERI, Taejon (Korea, Republic of)


    Dynamic system characteristics tests were carried out for the power variation by using the high temperature/high pressure thermal-hydraulic test facility, VISTA(Experimental Verification by Integral Simulation of Transient and Accidents), which had been constructed to simulate the SMART-P by KAERI. Experimental tests have been performed to investigate the thermal-hydraulic dynamic characteristics of the primary and the secondary systems in the range of 5% to 85% power. Automatic PID control logics were developed and installed to the VISTA facility to control the major thermal hydraulic parameters. Power was changed with either a step or a ramp changing method from the reference power of 10%, 25%, 50% and 75% to 5% or 10% higher power. It was found that there is no noticeable difference in the responses between a step and a ramp changing method. When unique constants of P, I, and D were used in the range of 5% to 85% power, it was found to be liable to lose the system control. Further studies are required to quantify the controllability and the time constants of the major thermal hydraulic parameters.

  18. Two-axis hydraulic joint for high speed, heavy lift robotic operations

    Vaughn, M.R.; Robinett, R.D.; Phelan, J.R.; VanZuiden, D.M.


    A hydraulically driven universal joint was developed for a heavy lift, high speed nuclear waste remediation application. Each axis is driven by a simple hydraulic cylinder controlled by a jet pipe servovalve. Servovalve behavior is controlled by a force feedback control system, which damps the hydraulic resonance. A prototype single joint robot was built and tested. A two joint robot is under construction.

  19. Parameter Design for the Energy-Regeneration System of Series Hydraulic-Hybrid Bus

    SONG Yunpu


    Full Text Available This paper simplifies the energy recovery process in the series hydraulic hybrid bus’ energy regeneration system into a process in which the main axle’s moment of inertia drives the secondary element variable delivery pump/motor and brings hydraulic oil from the oil tank to the accumulator. This process enables braking of the vehicle and also allows recovery of energy to the accumulator. Based on the flow equation for the secondary element variable delivery pump/motor and the torque equilibrium equation for its axle, the force equilibrium equation for vehicle braking and the pressure variation and flow continuity equations for the accumulator, simulation studies are conducted to analyze the effects of various system parameters, such as accumulator capacity, displacement of the secondary element variable delivery pump/motor, initial operating pressure of the system, etc. on system performance during regenerative braking.  

  20. Dynamic Modeling of Hydraulic Power Steering System with Variable Ratio Rack and Pinion Gear

    Zhang, Nong; Wang, Miao

    A comprehensive mathematical model of a typical hydraulic power steering system equipped with variable ratio rack and pinion gear is developed. The steering system’s dynamic characteristics are investigated and its forced vibrations are compared with those obtained from a counterpart system with a constant ratio rack and pinion gear. The modeling details of the mechanism subsystem, hydraulic supply lines subsystem and the rotary spool valve subsystem are provided and included in the integrated steering system model. The numerical simulations are conducted to investigate the dynamics of the nonlinear parametric steering system. From the comparison between simulated results and the experimental ones, it is shown that the model accurately integrates the boost characteristics of the rotary spool valve which is the key component of hydraulic power steering system. The variable ratio rack-pinion gear behaviors significantly differently from its constant ratio counterpart does. It significantly affects not only the system natural frequencies but also reduces vibrations under constant rate and ramp torque steering inputs. The developed steering model produces valid predictions of the system’s behavior and therfore could assist engineers in the design and analysis of integrated steering systems.


    Andersen, Torben Ole; Hansen, Michael Rygaard; Pedersen, Henrik C.;


    Generally most hydraulic systems are intrensically non-linear, why applying linear control techniques typically results in conservatively dimensioned controllers to obtain stable performance. Non-linear control techniques have the potential of overcoming these problems, and in this paper the focus...... is on developing and applying several different feedback linearisation (FL) controllers to the individual servo actuators in a hydraulically driven servo robot to evaluate and compare their possiblities and limitations. This is done based on both simulation and experimental results....

  2. Thermal Hydraulic Analysis of a Passive Residual Heat Removal System for an Integral Pressurized Water Reactor


    A theoretical investigation on the thermal hydraulic characteristics of a new type of passive residual heat removal system (PRHRS), which is connected to the reactor coolant system via the secondary side of the steam generator, for an integral pressurized water reactor is presented in this paper. Three-interknited natural circulation loops are adopted by this PRHRS to remove the residual heat of the reactor core after a reactor trip. Based on the one-dimensional model and a simulation code (S...

  3. Use of hydraulic models to identify and resolve design isssues in FGD systems

    Strock, T.W. [Babcock & Wilcox, Alliance, OH (United States); Gohara, W.F. [Babcock & Wilcox, Barberton, OH (United States)


    The hydraulics within a wet flue gas desulfurization (FGD) scrubber involve several complex two-phase gas/liquid interactions that directly affect the scrubber pressure drop, mist elimination efficiency, and the mass transfer process of SO{sub 2} removal. Current industrial efforts to develop cost effective, high-efficiency wet FGD scrubbers are focusing, in part, on the hydraulics. The development of an experimental approach and test facility for understanding and optimizing wet scrubber flow characteristics has been completed. Hydraulic models simulate full-scale units and allow the designer to view the gas/liquid flow interactions. Modeling procedures for downsizing the wet scrubber for the laboratory have been developed and validated with field data comparisons. A one-eighth scale hydraulic model has been used to study several FGD scrubber design issues. Design changes to reduce capital and operating cost have been developed and tested. Recently, the model was used to design a commercial, uniform flow, high gas velocity absorber for the next generation of FGD systems.

  4. Thermal-Hydraulic System Codes in Nulcear Reactor Safety and Qualification Procedures

    Alessandro Petruzzi


    Full Text Available In the last four decades, large efforts have been undertaken to provide reliable thermal-hydraulic system codes for the analyses of transients and accidents in nuclear power plants. Whereas the first system codes, developed at the beginning of the 1970s, utilized the homogenous equilibrium model with three balance equations to describe the two-phase flow, nowadays the more advanced system codes are based on the so-called “two-fluid model” with separation of the water and vapor phases, resulting in systems with at least six balance equations. The wide experimental campaign, constituted by the integral and separate effect tests, conducted under the umbrella of the OECD/CSNI was at the basis of the development and validation of the thermal-hydraulic system codes by which they have reached the present high degree of maturity. However, notwithstanding the huge amounts of financial and human resources invested, the results predicted by the code are still affected by errors whose origins can be attributed to several reasons as model deficiencies, approximations in the numerical solution, nodalization effects, and imperfect knowledge of boundary and initial conditions. In this context, the existence of qualified procedures for a consistent application of qualified thermal-hydraulic system code is necessary and implies the drawing up of specific criteria through which the code-user, the nodalization, and finally the transient results are qualified.

  5. Test Rig Design and Presentation for a Hydraulic Yaw System

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole


    dynamics under real conditions. The behavior of the system is analyzed with regard to 20 years of operation. This is for example done by applying loads from different design load cases, e.g. normal turbulence, extreme turbulence and different fault scenarios on the turbine. The paper first presents...... an introduction with the current state of the art and problem description, followed by a system description, where the system is designed and dimensioned. Based on the design, results from the test rig are presented and analyzed. Finally a conclusion summing up the design, model and test results is given....

  6. Hydraulic characterization of an activated sludge reactor with recycling system by tracer experiment and analytical models.

    Sánchez, F; Viedma, A; Kaiser, A S


    Fluid dynamic behaviour plays an important role in wastewater treatment. An efficient treatment requires the inexistence of certain hydraulic problems such as dead zones or short-circuiting flows. Residence time distribution (RTD) analysis is an excellent technique for detecting these inefficiencies. However, many wastewater treatment installations include water or sludge recycling systems, which prevent us from carrying out a conventional tracer pulse experiment to obtain the RTD curve of the installation. This paper develops an RTD analysis of an activated sludge reactor with recycling system. A tracer experiment in the reactor is carried out. Three analytical models, derived from the conventional pulse model, are proposed to obtain the RTD curve of the reactor. An analysis of the results is made, studying which model is the most suitable for each situation. This paper is useful to analyse the hydraulic efficiency of reactors with recycling systems.

  7. 综采工作面液压支架集控系统设计研究%Design of hydraulic support system for hydraulic support in fully mechanized mining face



    In view of the present stage of our country's domestic hydraulic support control system has the problem of poor real-time, low reliability and low degree of automation. This paper designs the hydraulic support system of hydraulic support in the fully mechanized working face, and introduces the hardware and software design of the system. The system has high real-time performance, stable communication, high degree of integration, and can meet the requirements of the establishment of high efifciency fully mechanized coal face.%针对现阶段我国的国产液压支架控制系统有实时性差、可靠性低、自动化程度较低等问题,设计了综采工作面液压支架集控系统,该文介绍了该系统硬件组成与软件设计,分析了液压支架集控的实现过程。该系统实时性高,通信稳定,集控程度高,能满足建立高产高效综采工作面的要求。

  8. Mechanical Engineering Design Project report: Enabler control systems

    Cullen, Christian; Delvecchio, Dave; Scarborough, Alan; Havics, Andrew A.


    The Controls Group was assigned the responsibility for designing the Enabler's control system. The requirement for the design was that the control system must provide a simple user interface to control the boom articulation joints, chassis articulation joints, and the wheel drive. The system required controlling hydraulic motors on the Enabler by implementing 8-bit microprocessor boards. In addition, feedback to evaluate positions and velocities must be interfaced to provide the operator with confirmation as well as control.

  9. Application of Rectangular Integral to Numerical Simulation of Hydraulic Transients in Complex Pipeline Systems

    万五一; 毛欣炜; 崔秀红


    The hydraulic oscillation of surge tank was analyzed through numerical simulation.A rectangular integral scheme was established in order to improve the numerical model.According to the boundary control equation of surge tank, the rectangular integral scheme omits the second-order infinitesimal and simplifies the solving process.An example was provided to illustrate the rectangular integral scheme, which is compared with the traditional trapezoid integral scheme.Appropriate numerical solutions were gained th...

  10. Free-piston Stirling hydraulic engine and drive system for automobiles

    Beremand, D. G.; Slaby, J. G.; Nussle, R. C.; Miao, D.


    The calculated fuel economy for an automotive free piston Stirling hydraulic engine and drive system using a pneumatic accumulator with the fuel economy of both a conventional 1980 spark ignition engine in an X body class vehicle and the estimated fuel economy of a 1984 spark ignition vehicle system are compared. The results show that the free piston Stirling hydraulic system with a two speed transmission has a combined fuel economy nearly twice that of the 1980 spark ignition engine - 21.5 versus 10.9 km/liter (50.7 versus 25.6 mpg) under comparable conditions. The fuel economy improvement over the 1984 spark ignition engine was 81 percent. The fuel economy sensitivity of the Stirling hydraulic system to system weight, number of transmission shifts, accumulator pressure ratio and maximum pressure, auxiliary power requirements, braking energy recovery, and varying vehicle performance requirements are considered. An important finding is that a multispeed transmission is not required. The penalty for a single speed versus a two speed transmission is about a 12 percent drop in combined fuel economy to 19.0 km/liter (44.7 mpg). This is still a 60 percent improvement in combined fuel economy over the projected 1984 spark ignition vehicle.

  11. Staged cost optimization of urban storm drainage systems based on hydraulic performance in a changing environment

    M. Maharjan


    Full Text Available Urban flooding causes large economic losses, property damage and loss of lives. The impact of environmental changes, mainly urbanization and climatic change, leads to increased runoff and peak flows which the drainage system must be able to cope with to reduce potential damage and inconvenience. Allowing for detention storage to compliment the conveyance capacity of the drainage system network is one of the approaches to reduce urban floods. Contemporary practice is to design systems against stationary environmental forcings – including design rainfall, landuse, etc. Due to the rapid change in the climate- and the urban environment, this approach is no longer appropriate, and explicit consideration of gradual changes during the life-time of the drainage system is warranted. In this paper, a staged cost optimization tool based on the hydraulic performance of the drainage system is presented. A one dimensional hydraulic model is used for hydraulic evaluation of the network together with a genetic algorithm based optimization tool to determine optimal intervention timings and responses over the analysis period. The model was applied in a case study area in the city of Porto Alegre, Brazil. It was concluded that considerable financial savings and/or additional level of flood-safety can be achieved by approaching the design problem as a staged plan rather than one-off scheme.

  12. Staged cost optimization of urban storm drainage systems based on hydraulic performance in a changing environment

    Maharjan, M.; Pathirana, A.; Gersonius, B.; Vairavamoorthy, K.


    Urban flooding causes large economic losses, property damage and loss of lives. The impact of environmental changes, mainly urbanization and climatic change, leads to increased runoff and peak flows which the drainage system must be able to cope with to reduce potential damage and inconvenience. Allowing for detention storage to compliment the conveyance capacity of the drainage system network is one of the approaches to reduce urban floods. Contemporary practice is to design systems against stationary environmental forcings - including design rainfall, landuse, etc. Due to the rapid change in the climate- and the urban environment, this approach is no longer appropriate, and explicit consideration of gradual changes during the life-time of the drainage system is warranted. In this paper, a staged cost optimization tool based on the hydraulic performance of the drainage system is presented. A one dimensional hydraulic model is used for hydraulic evaluation of the network together with a genetic algorithm based optimization tool to determine optimal intervention timings and responses over the analysis period. The model was applied in a case study area in the city of Porto Alegre, Brazil. It was concluded that considerable financial savings and/or additional level of flood-safety can be achieved by approaching the design problem as a staged plan rather than one-off scheme.

  13. Staged cost optimization of urban storm drainage systems based on hydraulic performance in a changing environment

    M. Maharjan


    Full Text Available Urban flooding causes large economic losses, property damage and loss of lives. The impact of environmental changes mainly, the urbanization and the climatic change leads to increased runoff and increased peak flows which the drainage system must be able to cope with to overcome possible damage and inconveniences caused by the induced flooding. Allowing for detention storage to compliment the capacity of the drainage system network is one of the approaches to reduce urban floods. The traditional practice was to design systems against stationary environmental forcings – including design rainfall, landuse, etc. Due to the rapid change in climate-environment, this approach is no longer economically viable and safe, and explicit consideration of changes that gradually take place during the life-time of the drainage system is warranted. In this paper, a staged cost optimization tool based on the hydraulic performance of the drainage system is presented. A one dimensional hydraulic model is used for hydraulic evaluation of the network together with a genetic algorithm based optimization tool to determine optimal intervention timings and amounts throughout the lifespan of the drainage network. The model was applied in a case study area in the city of Porto Alegre, Brazil. It was concluded that considerable financial savings and/or additional level of flood-safety can be achieved by approaching the design problem as a staged plan rather than one-off scheme.

  14. Hydraulic conductivity of active layer soils in the McMurdo Dry Valleys, Antarctica: Geological legacy controls modern hillslope connectivity

    Schmidt, Logan M.; Levy, Joseph S.


    Spatial variability in the hydraulic and physical properties of active layer soils influences shallow groundwater flow through cold-desert hydrological systems. This study measures the saturated hydraulic conductivity and grain-size distribution of 90 soil samples from the McMurdo Dry Valleys (MDV), Antarctica-primarily from Taylor Valley-to determine what processes affect the spatial distribution of saturated hydraulic conductivity in a simple, mineral-soil-dominated natural hillslope laboratory. We find that the saturated hydraulic conductivity and the grain-size distribution of soils are organized longitudinally within Taylor Valley. Soils sampled down-valley near the coast have a higher percentage of fine-sized sediments (fine sand, silt, clay) and lower saturated hydraulic conductivities than soils collected up-valley near Taylor Glacier (1.3 × 10- 2 vs. 1.2 × 10- 1 cm/s). Soils collected mid-valley have intermediate amounts of fines and saturated hydraulic conductivity values consistent with a hydrogeologic gradient spanning the valley from high inland to low near the coast. These results suggest the organization of modern soil properties within Taylor Valley is a relict signature from past glaciations that have deposited soils of decreasing age toward the mouth of the valley, modified by fluvial activity acting along temporal and microclimate gradients.




    Full Text Available This study investigated the thermal hydraulic issues in the Containment Filtered Venting System (CFVS for a long operating time using the MELCOR computer code. The modeling of the CFVS, including the models for pool scrubbing and the filter, was added to the input file for the OPR-1000, and a Station Blackout (SBO was chosen as an accident scenario. Although depressurization in the containment building as a primary objective of the CFVS was successful, the decontamination feature by scrubbing and filtering in the CFVS for a long operating time could fail by the continuous evaporation of the scrubbing solution. After the operation of the CFVS, the atmosphere temperature in the CFVS became slightly above the water saturation temperature owing to the release of an amount of steam with high temperature from the containment building to the scrubbing solution. Reduced pipe diameters at the inlet and outlet of the CFVS vessel mitigated the evaporation of scrubbing water by controlling the amount of high-temperature steam and the water saturation temperature.

  16. Seismic Proofing Capability of the Accumulated Semiactive Hydraulic Damper as an Active Interaction Control Device with Predictive Control

    Ming-Hsiang Shih


    Full Text Available The intensity of natural disasters has increased recently, causing buildings’ damages which need to be reinforced to prevent their destruction. To improve the seismic proofing capability of Accumulated Semiactive Hydraulic Damper, it is converted to an Active Interaction Control device and synchronous control and predictive control methods are proposed. The full-scale shaking table test is used to test and verify the seismic proofing capability of the proposed AIC with these control methods. This study examines the shock absorption of test structure under excitation by external forces, influences of prediction time, stiffness of the auxiliary structure, synchronous switching, and asynchronous switching on the control effects, and the influence of control locations of test structure on the control effects of the proposed AIC. Test results show that, for the proposed AIC with synchronous control and predictive control of 0.10~0.13 seconds, the displacement reduction ratios are greater than 71%, the average acceleration reduction ratios are, respectively, 36.2% and 36.9%, at the 1st and 2nd floors, and the average base shear reduction ratio is 29.6%. The proposed AIC with suitable stiffeners for the auxiliary structure at each floor with synchronous control and predictive control provide high reliability and practicability for seismic proofing of buildings.

  17. Towards quantitative root hydraulic phenotyping: novel mathematical functions to calculate plant-scale hydraulic parameters from root system functional and structural traits.

    Meunier, F; Couvreur, V; Draye, X; Vanderborght, J; Javaux, M


    Predicting root water uptake and plant transpiration is crucial for managing plant irrigation and developing drought-tolerant root system ideotypes (i.e. ideal root systems). Today, three-dimensional structural functional models exist, which allows solving the water flow equation in the soil and in the root systems under transient conditions and in heterogeneous soils. Yet, these models rely on the full representation of the three-dimensional distribution of the root hydraulic properties, which is not always easy to access. Recently, new models able to represent this complex system without the full knowledge of the plant 3D hydraulic architecture and with a limited number of parameters have been developed. However, the estimation of the macroscopic parameters a priori still requires a numerical model and the knowledge of the full three-dimensional hydraulic architecture. The objective of this study is to provide analytical mathematical models to estimate the values of these parameters as a function of local plant general features, like the distance between laterals, the number of primaries or the ratio of radial to axial root conductances. Such functions would allow one to characterize the behaviour of a root system (as characterized by its macroscopic parameters) directly from averaged plant root traits, thereby opening new possibilities for developing quantitative ideotypes, by linking plant scale parameters to mean functional or structural properties. With its simple form, the proposed model offers the chance to perform sensitivity and optimization analyses as presented in this study.

  18. Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.

    Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L


    Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion.

  19. An experimental study of the dual-loop control of electro-hydraulic load simulator (EHLS)

    Wang Chengwen; Jiao Zongxia; Wu Shuai; Shang Yaoxing


    This paper investigates motion coupling disturbance (the so called surplus torque) in the hardware-in-the-loop (HIL) experiments. The‘‘velocity synchronization scheme’’ was proposed by Jiao for an electro-hydraulic load simulator (EHLS) in 2004. In some situations, however, the scheme is limited in the implementation for certain reasons, as is the case when the actuator’s valve signal is not available or it is seriously polluted by noise. To solve these problems, a ‘‘dual-loop scheme’’ is developed for EHLS. The dual-loop scheme is a combination of a torque loop and a position synchronization loop. The role of the position synchronization loop is to decouple the motion disturbance caused by the actuator system. To verify the feasibility and effectiveness of the proposed scheme, extensive simulations are performed using AMESim. Then, the performance of the developed method is validated by experiments.

  20. Determination of minimum sample size for fault diagnosis of automobile hydraulic brake system using power analysis

    V. Indira


    Full Text Available Hydraulic brake in automobile engineering is considered to be one of the important components. Condition monitoring and fault diagnosis of such a component is very essential for safety of passengers, vehicles and to minimize the unexpected maintenance time. Vibration based machine learning approach for condition monitoring of hydraulic brake system is gaining momentum. Training and testing the classifier are two important activities in the process of feature classification. This study proposes a systematic statistical method called power analysis to find the minimum number of samples required to train the classifier with statistical stability so as to get good classification accuracy. Descriptive statistical features have been used and the more contributing features have been selected by using C4.5 decision tree algorithm. The results of power analysis have also been verified using a decision tree algorithm namely, C4.5.

  1. Speed-variable Switched Differential Pump System for Direct Operation of Hydraulic Cylinders

    Schmidt, Lasse; Roemer, Daniel Beck; Pedersen, Henrik Clemmensen;


    Efforts to overcome the inherent loss of energy due to throttling in valve driven hydraulic systems are many, and various approaches have been proposed by research communities as well as the industry. Recently, a so-called speed-variable differential pump was proposed for direct drive of hydraulic...... differential cylinders. The main idea was here to utilize an electric rotary drive, with the shaft interconnected to two antiparallel fixed displacement gear pumps, to actuate a differential cylinder. With the design carried out such that the area ratio of the cylinder matches the displacement ratio of the two...... gear pumps, the throttling losses are confined to cross port leakage in the cylinder and leakage of the pumps. However, it turns out that the volumetric pump losses and the pressure dynamics of the cylinder and connecting pipes may cause pressure increase- or decrease in the cylinder chambers, which...

  2. Metallic particles into mechanical and hydraulic systems in agricultural and construction machines

    Silva, Jair Rosas da; Silva, Deise Paula da [Instituto Agronomico de Campinas (IAC), Campinas, SP (Brazil). Centro de Engenharia Agricola; Bormio, Marcos Roberto [Universidade Estadual Paulista (UNESP), Bauru, SP (Brazil). Fac. de Engenharia


    The lubricant oil analysis are an indicator of the conditions how the lubricant is, may to allow the prevision of damages that occurred into machine due to the internal abrasion of hydraulic and mechanical components of the machines. The present study had the objective to determine the kind and quantity of the metallic particles that occurred into the lubricant oil of the mechanical and hydraulic compartments of the energy transmission systems of three kinds of machines: a tracked-tractor, a sugarcane harvester and a group of power-shovels. The metallic particles presents into these compartments were determined under laboratory tests and concerning to the following elements: iron, copper, chromium, lead, nickel, aluminum, silex, tin and molybdenum. About to the tracked-tractor, the metallic contaminators into to the oil charges surpasses the tolerate levels, considering the technical standards adopted in this evaluation. In the sugarcane harvester only a metallic element in excess was identified and, in a power-shovel group it was showed the need to correct air false entrances in the hydraulic or mechanical systems due the high presence of silex element. (author)

  3. Environmentally Friendly, Rheoreversible, Hydraulic-fracturing Fluids for Enhanced Geothermal Systems

    Shao, Hongbo; Kabilan, Senthil; Stephens, Sean A.; Suresh, Niraj; Beck, Anthon NR; Varga, Tamas; Martin, Paul F.; Kuprat, Andrew P.; Jung, Hun Bok; Um, Wooyong; Bonneville, Alain; Heldebrant, David J.; Carroll, KC; Moore, Joseph; Fernandez, Carlos A.


    Cost-effective creation of high-permeability reservoirs inside deep crystalline bedrock is the primary challenge for the feasibility of enhanced geothermal systems (EGS). Current reservoir stimulation entails adverse environmental impacts and substantial economic costs due to the utilization of large volumes of water “doped” with chemicals including rheology modifiers, scale and corrosion inhibitors, biocides, friction reducers among others where, typically, little or no information of composition and toxicity is disclosed. An environmentally benign, CO2-activated, rheoreversible fracturing fluid has recently been developed that significantly enhances rock permeability at effective stress significantly lower than current technology. We evaluate the potential of this novel fracturing fluid for application on geothermal sites under different chemical and geomechanical conditions, by performing laboratory-scale fracturing experiments with different rock sources under different confining pressures, temperatures, and pH environments. The results demonstrate that CO2-reactive aqueous solutions of environmentally amenable Polyallylamine (PAA) represent a highly versatile fracturing fluid technology. This fracturing fluid creates/propagates fracture networks through highly impermeable crystalline rock at significantly lower effective stress as compared to control experiments where no PAA was present, and permeability enhancement was significantly increased for PAA compared to conventional hydraulic fracturing controls. This was evident in all experiments, including variable rock source/type, operation pressure and temperature (over the entire range for EGS applications), as well as over a wide range of formation-water pH values. This versatile novel fracturing fluid technology represents a great alternative to industrially available fracturing fluids for cost-effective and competitive geothermal energy production.

  4. A fast building and effective hydraulic pediatric mock circulatory system for the evaluation of a left ventricular assist device.

    Huang, Feng; Ruan, Xiaodong; Zou, Jun; Qian, Wenwei; Fu, Xin


    A mock circulatory system (MCS) has been proven a useful tool in the development of a ventricular assist device. Nowadays a MCS aimed at the evaluation of pediatric blood pumps, which require many different considerations compared with that of adults, has become an urgent need. This article presents the details on how the dynamic process of the left ventricle, which is described in terms of the pressure-volume loop (P-V loop), and the properties of the circulation such as compliance and resistance are simulated by hydraulic elements. A simple control method is introduced to reproduce the physiological afterload and preload sensitivities of the mock ventricle for the first time. Hemodynamic performance of the system is obtained by medical sensors to validate the similarity of the device to the native cardiovascular system. The actual sensitivities of the mock ventricle are obtained intuitively from the changes of the P-V loops. The aortic input impedance of the MCS is also obtained and compared with the data from previous medical reports. At last a pediatric left ventricular assist device (LVAD) prototype is introduced for testing to further verify the effectiveness of the MCS. The experimental results indicate that this pediatric MCS is capable of reproducing basic hemodynamic characteristics of a child in both normal and pathological conditions and it is sufficient for testing a pediatric LVAD. Besides, most components constituting the main hydraulic part of this MCS are inexpensive off-the-shelf products, making the MCS easy and fast to build.

  5. Study on Wireless Network Communication in Stage Hydraulic Monitoring System Based on Internet of Things


    A novel stage hydraulic monitoring system based on Internet of Things (IoT) is proposed in this paper. Compared with the traditional wired system, the proposed system is a flexible working method and can save the cost. Furthermore, it has the low power consumption, high safety, and large scale network. The real-time pressure and flow data can be collected by using the nodes in ZigBee network. The fault detection and diagnosis process was used in this study, which was facilitated by measuring ...

  6. Software Tool for Automated Failure Modes and Effects Analysis (FMEA) of Hydraulic Systems

    Stecki, J. S.; Conrad, Finn; Oh, B.


    Offshore, marine,aircraft and other complex engineering systems operate in harsh environmental and operational conditions and must meet stringent requirements of reliability, safety and maintability. To reduce the hight costs of development of new systems in these fields improved the design...... management techniques and a vast array of computer aided techniques are applied during design and testing stages. The paper present and discusses the research and development of a software tool for automated failure mode and effects analysis - FMEA - of hydraulic systems. The paper explains the underlying...

  7. Developing a Tool Point Control Scheme for a Hydraulic Crane Using Interactive Real-time Dynamic Simulation

    Pedersen, Mikkel Melters; Hansen, Michael Rygaard; Ballebye, Morten


    This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme...

  8. Resolution of thermal-hydraulic safety and licensing issues for the system 80+{sup {trademark}} design

    Carpentino, S.E.; Ritterbusch, S.E.; Schneider, R.E. [ABB-Combustion Engineering, Windsor, CT (United States)] [and others


    The System 80+{sup {trademark}} Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC`s new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs.

  9. Development of numerical simulation system for thermal-hydraulic analysis in fuel assembly of sodium-cooled fast reactor

    Ohshima, Hiroyuki; Uwaba, Tomoyuki [Japan Atomic Energy Agency (4002 Narita, O-arai, Ibaraki 311-1393, Japan) (Japan); Hashimoto, Akihiko; Imai, Yasutomo [NDD Corporation (1-1-6 Jounan, Mito, Ibaraki 310-0803, Japan) (Japan); Ito, Masahiro [NESI Inc. (4002 Narita, O-arai, Ibaraki 311-1393, Japan) (Japan)


    A numerical simulation system, which consists of a deformation analysis program and three kinds of thermal-hydraulics analysis programs, is being developed in Japan Atomic Energy Agency in order to offer methodologies to clarify thermal-hydraulic phenomena in fuel assemblies of sodium-cooled fast reactors under various operating conditions. This paper gives the outline of the system and its applications to fuel assembly analyses as a validation study.

  10. Development of numerical simulation system for thermal-hydraulic analysis in fuel assembly of sodium-cooled fast reactor

    Ohshima, Hiroyuki; Uwaba, Tomoyuki; Hashimoto, Akihiko; Imai, Yasutomo; Ito, Masahiro


    A numerical simulation system, which consists of a deformation analysis program and three kinds of thermal-hydraulics analysis programs, is being developed in Japan Atomic Energy Agency in order to offer methodologies to clarify thermal-hydraulic phenomena in fuel assemblies of sodium-cooled fast reactors under various operating conditions. This paper gives the outline of the system and its applications to fuel assembly analyses as a validation study.

  11. Friction compensation for low velocity control of hydraulic flight motion simulator: A simple adaptive robust approach

    Yao Jianyong; Jiao Zongxia; Han Songshan


    Low-velocity tracking capability is a key performance of flight motion simulator (FMS),which is mainly affected by the nonlinear friction force.Though many compensation schemes with ad hoc friction models have been proposed,this paper deals with low-velocity control without friction model,since it is easy to be implemented in practice.Firstly,a nonlinear model of the FMS middle frame,which is driven by a hydraulic rotary actuator,is built.Noting that in the low velocity region,the unmodeled friction force is mainly characterized by a changing-slowly part,thus a simple adaptive law can be employed to learn this changing-slowly part and compensate it.To guarantee the boundedness of adaptation process,a discontinuous projection is utilized and then a robust scheme is proposed.The controller achieves a prescribed output tracking transient performance and final tracking accuracy in general while obtaining asymptotic output tracking in the absence of modeling errors.In addition,a saturated projection adaptive scheme is proposed to improve the globally learning capability when the velocity becomes large,which might make the previous proposed projection-based adaptive law be unstable.Theoretical and extensive experimental results are obtained to verify the high-performance nature of the proposed adaptive robust control strategy.

  12. Dynamic Analysis and Design Optimization of Series Hydraulic Hybrid System through Power Bond Graph Approach

    R. Ramakrishnan


    Full Text Available The availability of natural gas and crude oil resources has been declining over the years. In automobile sector, the consumption of crude oil is 63% of total crude oil production in the world. Hence, automobile industries are placing more emphasis on energy efficient hydraulic hybrid systems, which can replace their conventional transmission systems. Series hydraulic hybrid system (SHHS is a multidomain mechatronics system with two distinct power sources that includes prime mover and hydropneumatic accumulator. It replaces the conventional transmission system to drive the vehicle. The sizing of the subsystems in SHHS plays a major role in improving the energy efficiency of the vehicle. In this paper, a power bond graph approach is used to model the dynamics of the SHHS. The obtained simulation results indicate the energy flow during various modes of operations. It also includes the dynamic response of hydropneumatic accumulator, prime mover, and system output speed. Further, design optimization of the system is carried out to optimize the process parameters for maximizing the system energy efficiency. This leads to increase in fuel economy and environmentally friendly vehicle.

  13. The Maintenance of Heading Machine Hydraulic System%掘进机液压系统的维护



    The paper mainly discussed the rotation of hydraulic tank, oil return filter system and the axial piston pump of heading machine's hydraulic system, the adjustment of axial piston pump, relief valve pressure and one-way throttle valve and the maintenance of hydraulic system and the using of hydraulic components.%本文主要阐述了掘进机液压系统的液压油箱、液压系统的回油过滤器、轴向柱塞泵的旋转、轴向柱塞泵、溢流阀压力的调整、单向节流阀的调整、液压系统维护、液压元件的使用等维护.

  14. 远洋船用伸缩折叠起重机液压系统设计%Marine telescopic folding crane hydraulic system design

    卢志珍; 倪学虎; 舒希勇; 王成龙


    在分析伸缩折叠起重机对液压系统要求的基础上,针对起重机技术参数及客户要求提出了液压系统设计的思路.对关键液压元件——液压泵、液压马达、液压缸进行了计算选型,设计了液压原理图,并阐述了起重机液压回路的工作原理.%Based on the analysis of telescopic folding crane hydraulic system requirements,put forward the hydraulic system design thinking according to crane technical parameters and requirements of customers. Calculation and type selection of the key hydraulic components------hydraulic pump and hydraulic motor, hydraulic cylinder, design hydraulic principle diagram and expoundscrane hydraulic loop principle of work.

  15. Stabilization of soil hydraulic properties under a long term no-till system

    Luis Alberto Lozano


    Full Text Available The area under the no-tillage system (NT has been increasing over the last few years. Some authors indicate that stabilization of soil physical properties is reached after some years under NT while other authors debate this. The objective of this study was to determine the effect of the last crop in the rotation sequence (1st year: maize, 2nd year: soybean, 3rd year: wheat/soybean on soil pore configuration and hydraulic properties in two different soils (site 1: loam, site 2: sandy loam from the Argentinean Pampas region under long-term NT treatments in order to determine if stabilization of soil physical properties is reached apart from a specific time in the crop sequence. In addition, we compared two procedures for evaluating water-conducting macroporosities, and evaluated the efficiency of the pedotransfer function ROSETTA in estimating the parameters of the van Genuchten-Mualem (VGM model in these soils. Soil pore configuration and hydraulic properties were not stable and changed according to the crop sequence and the last crop grown in both sites. For both sites, saturated hydraulic conductivity, K0, water-conducting macroporosity, εma, and flow-weighted mean pore radius, R0ma, increased from the 1st to the 2nd year of the crop sequence, and this was attributed to the creation of water-conducting macropores by the maize roots. The VGM model adequately described the water retention curve (WRC for these soils, but not the hydraulic conductivity (K vs tension (h curve. The ROSETTA function failed in the estimation of these parameters. In summary, mean values of K0 ranged from 0.74 to 3.88 cm h-1. In studies on NT effects on soil physical properties, the crop effect must be considered.

  16. Quarter Car Active Suspension System Control Using PID Controller tuned by PSO

    Wissam H. Al-Mutar


    The objective of this paper is to design an efficient control scheme for car suspension system. The purpose of suspension system in vehicles is to get more comfortable riding and good handling with road vibrations. A nonlinear hydraulic actuator is connected to passive suspension system in parallel with damper. The Particles Swarm Optimization is used to tune a PID controller for active suspension system. The designed controller is applied for quarter car suspension system and result is compa...

  17. Drawing a pictogram operator - hydraulic stowing assembly

    Bukhgol' ts, V.P.; Dinershtein, V.A.


    Hydraulic stowing is widely used during the extraction of coal from seams prone to spontaneous ignition or from seams situated under preserved structures. Experience has shown that the presence of a considerable number of controlling and measuring devices on hydraulic stowing assemblies results in erratic operations. The authors, after examining the controls of the hydraulic stowing complexes, recommend that all functions which the operator might perform badly or not at all should be controlled automatically. The operator must, however, have access to manual controls which should be included in the system in order to achieve an effective and trouble free operation. The authors propose a pictogram to explain the relationship between the human operator and the hydraulic complex, based on structural diagrams. The system developed, which was tried out at the Koksovaya mine, increased the efficiency of the complex and reduced the work load of the operator. 3 references.

  18. Hydrologic connectivity responses to thermally-controlled changes in hydraulic gradients on Arctic hillslopes

    Rushlow, C. R.; Godsey, S.


    Active layer freeze and thaw exerts a first-order control on Arctic hillslope hydrology, and thus the weathering and transport of material within Arctic watersheds. We investigate how changes in active layer thaw depth over the summer warm season affect the storage and flux of water, especially in response to snowmelt and storm events. We focus our investigation on six water tracks -linear regions of preferential, but unchannelized flow- draining the hillslopes of the Upper Kuparuk River basin in northern Alaska. Water tracks form a slight topographic depression on the hillslope, and snow depth surveys from before spring snowmelt indicate that snow depths are deeper in the water tracks than on the surrounding hillslope. Thermocouples installed at ten intervals up to 35 cm below ground on the inside, edge and outside of each water track monitored ground temperatures as the active layer expanded throughout the summer. In general, the amplitude of diurnal temperature variability decreases with increasing depth, and the amplitude increases over the course of the season at all depths. Temperatures inside the water track have a muted diurnal cyclicity relative to the temperatures on the edge and outside the water track. Furthermore, surface soil moisture content inside the water tracks is consistently higher than outside. Both of these observations reflect that water moderates subsurface temperatures. Thaw depth surveys perpendicular to the water track show that over the course of the season, thaw depth becomes greater within the water track, increasing the hydraulic gradient from the surrounding hillslope to the water track. Thus, during annual late May snowmelt the surface topography is the main control on water flow paths, but as temperatures continue to warm, the topography of the active layer dominates. Thirty pressure transducers deployed in shallow groundwater wells along perpendicular transects of one water track measure changes in water table elevation during

  19. 电液伺服加载系统多余力分析%Research on Surplus Force of Electro-hydraulic Servo Loading System

    韩洋; 吴晖; 曾毅; 潘阳


    Hydraulic cylinder position control is widely used. Electro-hydraulic servo loading system is often used to simulate the real load. This article firstly build the mathematical model of electro-hydraulic proportional position and electro-hydraulic servo loading systems. Then analyze the surplus torque generated in loading process to find out the related factors influencing the surplus torque. Finally adopt“PID+speed feed-forward compensation”to improve comprehensive performance of loading system.%液压缸位置控制广泛应用于各类液压控制系统中,常采用电液伺服加载系统模拟其运动过程中的真实负载。该文首先建立电液比例位置控制和电液伺服加载系统的数学模型;然后对加载过程中产生的多余力进行分析,找出影响多余力的相关因素;最后采用“PID+速度前馈补偿”来改善加载系统的综合性能。

  20. Design and Experimental Validation of Hydraulic Yaw System for Multi MW Wind Turbine

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole


    To comply with the increasing demands for life time and reliability of wind turbines as these grow in size, new measures needs to be taken in the design of wind turbines and components hereof. One critical point is the initial testing of the components and systems before they are implemented...... environment. The model and the test rig are tested up against different design load cases and the results are compared. The experiments show that the model is valid for comparing the overall dynamics of the hydraulic yaw system. Based on the results it is concluded that the model derived is suitable...