Single Edge Meter Out Control for Mobile Machinery

2014 ◽  
Author(s):  
Milos Vukovic ◽  
Hubertus Murrenhoff
Keyword(s):  
Control Strategies ◽  
Industrial Applications ◽  
Mode Switching ◽  
Hydraulic Systems ◽  
Single Edge ◽  
Load Pressure ◽  
System Architectures ◽  
Operating Modes ◽  
System Pressure ◽  
Mobile Machinery

To decrease throttling losses in mobile hydraulic systems a number of new system architectures have been introduced in recent years. The concept of independent metering (IM), developed in the seventies, shows a lot of promise [1]. By allowing the meter-in as well as meter-out edges to be controlled separately, additional operating modes are created allowing a more efficient adaptation of system pressure to load pressure [2, 3]. Despite these advantages IM circuits have yet to find their way into industrial applications. This is mainly due to the related increase in component costs and more demanding control strategies. Additionally, the effect of mode switching on actuator motion and operator comfort is still unclear and considered to be a challenge. The STEAM mobile hydraulic system currently being developed in Aachen, Germany uses a number of new features to improve total machine efficiency [4]. Among others is the use of a new independent metering circuit called single edge meter-out control. Unlike other IM configurations, only one proportional valve is used to control cylinder motion. This paper introduces the new concept and discusses its advantages.

scholarly journals Present and Future of Supercapacitor Technology Applied to Powertrains, Renewable Generation and Grid Connection Applications

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3060
Author(s):  
Gustavo Navarro ◽  
Jorge Torres ◽  
Marcos Blanco ◽  
Jorge Nájera ◽  
Miguel Santos-Herran ◽  
...  
Keyword(s):  
Energy Storage ◽  
Control Strategies ◽  
Industrial Applications ◽  
Frequency Regulation ◽  
Scientific Publications ◽  
Industrial Systems ◽  
Grid Connection ◽  
Huge Impact ◽  
Traction Drives ◽  
Electric Traction

Energy storage systems (ESS) are becoming essential as a solution for troublesome industrial systems. This study focuses on the application of a type of ESS, a high-power technology known in the literature as supercapacitors or electric double layer capacitors (EDLC). This technology has had a huge impact during the last decade on research related to the electric traction drives, renewable sources and powergrids. Related to this aspect, this paper summarizes the most relevant scientific publications in the last five years that study the use of supercapacitor technology (SCs) in electric traction applications (drives for rail vehicles and drives for road vehicles), generation systems for renewable energy (wind, solar and wave energy), and connection systems to the electric grid (voltage and frequency regulation and microgrids). The technology based on EDLC and the practical aspects that must be taken into account in the op-eration of these systems in industrial applications are briefly described. For each of the aforementioned applications, it is described how the problems are solved by using the energy storage technology, drawing the solutions proposed by different authors. Special attention is paid to the control strategies when combining SCs with other technologies, such as batteries. As a summary, some conclusions are collected drawn from the publications analyzed, evaluating the aspects in which it is necessary to conduct further research in order to facilitate the integration of EDLC technology.

Novel pressure control in supercritical fluid chromatography using a resistively heated restrictor

2009 ◽  
Vol 87 (3) ◽  
pp. 490-495 ◽  
Author(s):  
Jian Jun Li ◽  
Kevin B. Thurbide
Keyword(s):  
Supercritical Fluid ◽  
Supercritical Fluid Chromatography ◽  
Pressure Control ◽  
Detector Response ◽  
Operating Modes ◽  
System Pressure ◽  
Relative Standard ◽  
Flame Burner ◽  
Alternative Means ◽  
Column Pressure

An alternative means of independently controlling column pressure in supercritical fluid chromatography (SFC) by resistively heating the post-column restrictor is demonstrated. Compared to conventional block heating methods, resistive restrictor heating provides at least four times greater pressure programming rates and allows for much faster cooling times in between runs, thereby increasing sample throughput. When applying resistive restrictor heating in proximity to a flame ionization detector, the chromatographic baseline noise increases substantially and obscures peaks. However, adding about 100 mL/min of nitrogen into the flame burner essentially removes this noise and returns the detector response to normal. The analyte retention time in consecutive pressure gradient trials reproduces well with a minimal relative standard deviation of 0.36% (n = 3). The resistive restrictor heating technique presented is also found to be equally effective for either capillary or packed SFC operating modes. Results suggest that this method can potentially provide a simple, inexpensive, and convenient alternative to limited passive restrictors or more costly and complex backpressure regulators that are often used to maintain system pressure in supercritical fluid chromatography.

Modeling Cyclic Variability in Spark-Assisted HCCI

2008 ◽  
Vol 130 (5) ◽  
Author(s):  
C. Stuart Daw ◽  
K. Dean Edwards ◽  
Robert M. Wagner ◽  
Johney B. Green
Keyword(s):  
Control Strategies ◽  
Experimental Studies ◽  
Mode Switching ◽  
Load Range ◽  
Gasoline Engines ◽  
Cyclic Variability ◽  
Hcci Combustion ◽  
Quantitative Understanding ◽  
Low Dimensional ◽  
High Degree

Spark assist appears to offer considerable potential for increasing the speed and load range over which homogeneous charge compression ignition (HCCI) is possible in gasoline engines. Numerous experimental studies of the transition between conventional spark-ignited (SI) propagating-flame combustion and HCCI combustion in gasoline engines with spark assist have demonstrated a high degree of deterministic coupling between successive combustion events. Analysis of this coupling suggests that the transition between SI and HCCI can be described as a sequence of bifurcations in a low-dimensional dynamic map. In this paper, we describe methods for utilizing the deterministic relationship between cycles to extract global kinetic rate parameters that can be used to discriminate multiple distinct combustion states and develop a more quantitative understanding of the SI-HCCI transition. We demonstrate the application of these methods for indolene-containing fuels and point out an apparent HCCI mode switching not previously reported. Our results have specific implications for developing dynamic combustion models and feedback control strategies that utilize spark assist to expand the operating range of HCCI combustion.

Lyapunov Control Strategy for Thermoelectric Cooler Activating an Ice-Clamping System

2018 ◽  
Vol 10 (4) ◽  
Author(s):  
Alexandra Mironova ◽  
Paolo Mercorelli ◽  
Andreas Zedler
Keyword(s):  
Manufacturing Systems ◽  
Control Strategies ◽  
Industrial Applications ◽  
Machining Process ◽  
Free Form ◽  
Cooling Power ◽  
Machining Processes ◽  
Clamping System ◽  
Ice Strength ◽  
Free Form Surfaces

Deformation-free clamping plays an important role in manufacturing systems helping to ensure zero-defect production. The fixture of workpieces during machining processes poses challenges not only for microparts but also for thin-walled pieces or free-form surfaces in macromanufacturing. To address this challenge, a nontraditional adhesive technique, using frozen water to clamp, is introduced in this paper. By increasing the cooling power and thus reducing the temperature of the clamping plate, higher adhesive ice strength and, therefore, a safer clamping system during machining process, can be achieved. The objective of this investigation is to ensure a stable low temperature and to compensate for thermal disturbances. Thanks to their structural robustness, Lyapunov-based control strategies demonstrate an appropriate capability to achieve these results in real industrial applications. Model design of the clamping system as well as simulation and experimental results are shown and discussed.

Huge Forging Equipment Hydraulic System Dynamic Analysis

2012 ◽  
Vol 619 ◽  
pp. 459-462 ◽  
Author(s):  
Miao Xie ◽  
Jun Meng ◽  
Wen Xin Xu ◽  
Rong Bao Dong ◽  
Jian Liang Wang
Keyword(s):  
Hydraulic System ◽  
Simulation Models ◽  
Simulation Software ◽  
Hydraulic Systems ◽  
System Pressure ◽  
Hydraulic Hammer ◽  
Hammer Head ◽  
Working Principle ◽  
Switching Characteristics ◽  
Hammer Forging

In order to optimize the dynamic characteristic of hydraulic system of large forging equipment. It based on the model of one company of a certain aero-engine hydraulic system of hydraulic hammer forging, analysis the composition and working principle of hydraulic systems. Using simulation software AMESim, simulate the model of hydraulic systems and by changing the system pressure, flow and effect of the hammer-head stroke to explore this kind of switching characteristics of forging equipment’s hydraulic system. The result shows that this kind of simulation models can reflect the working status of hydraulic hammer well, and provide a technical reference for analysis and tuning equipment that with similar to forging equipment.

Analysis of Control Strategy for Extended-Range Electric Vehicle

2011 ◽  
Vol 135-136 ◽  
pp. 261-267
Author(s):  
Hai Tao Min ◽  
Dong Jin Ye ◽  
Yuan Bin Yu
Keyword(s):  
Electric Vehicles ◽  
Control Strategy ◽  
Optimal Strategy ◽  
Control Strategies ◽  
Power Train ◽  
Operating Modes ◽  
Load Following ◽  
Extended Range ◽  
Main Components ◽  
And Control

This paper introduced the structure of Extended-Range Electric Vehicles as well as its characteristics. Principle researches have been offered on the parameters matching of the power-train and main components. Operating modes and control strategies were discussed, especially the two control strategies of charge sustaining mode which is shown as load following strategy and engine optimal strategy, and the effects of both control strategies are simulated and analyzed. The results indicate that the load following strategy can obviously extend battery’s lifespan, but the engine optimal strategy can reduce fuel consumption and emission effectively.

STEAM: A Mobile Hydraulic System With Engine Integration

2013 ◽  
Author(s):  
Milos Vukovic ◽  
Sebastian Sgro ◽  
Hubertus Murrenhoff
Keyword(s):  
Hydraulic System ◽  
High Efficiency ◽  
Combustion Engine ◽  
Low Cost ◽  
Total System ◽  
Hydraulic Systems ◽  
Pressure System ◽  
Operating Modes ◽  
Hydraulic Design ◽  
Displacement Pump

In recent years, research institutions worldwide have developed a number of new mobile hydraulic systems. Despite their improved energy efficiency, these systems have yet to gain market acceptance due to their related increase in component costs and decrease in robustness. At the Institute for Fluid Power Drives and Controls in Aachen, a new system for mobile machines, named STEAM (Steigerung der Energieeffizienz in der Arbeitshydraulik mobiler Arbeitsmaschinen), is being developed using inexpensive off-the-shelf components. The aim is to improve the total system efficiency by considering all the subsystems in the machine. This is done by integrating the internal combustion engine (ICE) into the hydraulic design process. By using a constant pressure system in combination with a low-cost fixed displacement pump the hydraulic system is designed to ensure the ICE experiences a constantly high load in a region of high efficiency, so-called point operation. To decrease the hydraulic losses incurred when supplying the linear actuators with flow, an additional intermediate pressure rail with independent metering edges is used. This enables various energy efficient discrete operating modes, including energy regeneration and recuperation.

Special Issue on New Challenges in Robotics Technology

2017 ◽  
Vol 11 (3) ◽  
pp. 343-343
Author(s):  
Terenziano Raparelli ◽  
◽  
Pierluigi Beomonte Zobel
Keyword(s):  
High Speed ◽  
Autonomous Robots ◽  
Control Strategies ◽  
Industrial Applications ◽  
Assistive Devices ◽  
Service Robots ◽  
Practical Case ◽  
Special Issue ◽  
New Challenges ◽  
Robotic Devices

Robotics has reached a top technological level in recent years, a level at which it can be successfully used not only in structured spaces (for less complex applications) but also increasingly in unstructured spaces. Robotics technology is now used effectively in hospitals for rehabilitation and assistive devices, in the home for domestic applications, in the space for autonomous robots and automated vehicles, in amusement parks for entertainment attractions, and on the ground for military applications. In industrial applications, robotics has enlarged its scope with high-speed robots, cooperative robots, and smart robotic devices for production set-ups. These new applications have created new challenges in robotics. New materials have been developed to make frames lighter and smarter, new actuators and sensors have been made in compliance with specific applications and for more advanced performance, new flexible gripper devices have been produced with superior control systems, and new interfaces have been developed that are integrated with the devices and easier to use. This special issue features 18 research articles related to the latest research results and practical case studies in robotics technology. Subjects include robots for rehabilitation, robots as assistive devices, robots for agriculture, robots for exploration, robots for automation and industrial applications, service robots, new actuators, new sensors, new gripping devices, new control strategies, and robotic systems. We deeply appreciate the careful efforts of all the authors and thank the reviewers for their incisive efforts. Without these contributions, this special issue could not have been printed. We hope that this special issue will trigger further research on robotics technology. Finally a special memory of Cesare Rossi, one of the authors, that died suddenly after the preparation of the manuscript.

Experimental Validation of a Time Domain Cavitation Model for Switched Inertance Circuits

2017 ◽  
Author(s):  
Alexander C. Yudell ◽  
James D. Van de Ven
Keyword(s):  
Small Diameter ◽  
Practice Research ◽  
Reservoir Pressure ◽  
Hydraulic Systems ◽  
Cavitation Model ◽  
Local Pressure ◽  
Efficient Manner ◽  
Load Pressure ◽  
Power Circuit ◽  
Switching Valve

Switched inertance hydraulic systems are switch mode fluid power circuit topologies that allow the load pressure to be modulated in an efficient manner. A unique feature of these circuits is a long, small diameter, inertance tube, which stores energy in the fluid kinetic domain during a switching cycle. A barrier to application of these circuits is that current models require an elevated reservoir pressure, which is difficult to implement in practice. Research has focused on analyzing inertance tube wave delay effects in the frequency domain, which necessarily excludes non-linear physical phenomena such as cavitation and pressure dependent wave speed. A circuit with an ambient reservoir pressure exposes the fluid in the inertance tube to local pressure conditions where these non-ideal behaviors may have a strong effect on system dynamics. In this paper, a method of characteristics cavitation model with unsteady friction is presented that accurately captures the incidence and severity of cavitation in a long pipeline undergoing cyclic high and low pressure boundary conditions. This model is validated experimentally by examining the pressure response in a 3.95m steel pipeline with an upstream switching valve capable of 0.5ms transition at 120Hz. Experiments are conducted over a range of switching frequencies at 60% duty. The proposed pipeline model can be used to predict conditions leading to cavitation as well as help develop cavitation avoidance strategies, such as soft switching and utilization of line resonance.

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