scholarly journals Efficient SMA Actuation—Design and Control Concepts

Proceedings ◽  
2020 ◽  
Vol 64 (1) ◽  
pp. 20
Author(s):  
Paul Motzki
Keyword(s):  
High Speed ◽  
Thermal Activation ◽  
Energy Savings ◽  
Form Factors ◽  
High Energy ◽  
Innovative Design ◽  
Wide Range ◽  
Millisecond Range ◽  
And Control ◽  
High Energy Consumption

The versatility of the form factors of thermal shape memory alloys (SMA) in combination with their unique actuation and sensing abilities allow for the design and construction of innovative multifunctional systems. Despite the considerable number of advantages, such as their exceptional energy density, only a few SMA-based actuator systems are commercially available. One of the main reasons for this is their inefficient thermal activation and the resulting high energy consumption. The efficiency of SMA-based actuator systems can be improved by innovative design and control approaches. In the first part of this paper, the intelligent combination of SMA actuator wires with bi-stable, nonlinear spring elements is described. This combination eliminates the commonly quoted disadvantages of SMAs—slow actuation and energy inefficiency—for a wide range of applications. In particular, two energy-free actuator configurations are realized, which can be applied to any non-proportional actuation tasks. The second approach for the realization of high-speed actuation and energy efficiency is the activation of SMA wires with high voltage pulses, which leads to actuation times in the millisecond range and energy savings of up to 80% in comparison to the suppliers’ recommendations. It is shown that even high AC voltages such as typical mains supplies can be directly used for highly efficient SMA activation.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Detector commissioning and development for PETRA-III

2010 ◽  
Vol 1 (SRMS-7) ◽  
Author(s):  
David Pennicard ◽  
Heinz Graafsma ◽  
Michael Lohmann
Keyword(s):  
High Speed ◽  
Materials Science ◽  
Dynamic Range ◽  
Photon Counting ◽  
High Energy ◽  
X Rays ◽  
Silicon Detectors ◽  
Time Resolved ◽  
Wide Range ◽  
Synchrotron Light

The new synchrotron light source PETRA-III produced its first beam last year. The extremely high brilliance of PETRA-III and the large energy range of many of its beamlines make it useful for a wide range of experiments, particularly in materials science. The detectors at PETRA-III will need to meet several requirements, such as operation across a wide dynamic range, high-speed readout and good quantum efficiency even at high photon energies. PETRA-III beamlines with lower photon energies will typically be equipped with photon-counting silicon detectors for two-dimensional detection and silicon drift detectors for spectroscopy and higher-energy beamlines will use scintillators coupled to cameras or photomultiplier tubes. Longer-term developments include ‘high-Z’ semiconductors for detecting high-energy X-rays, photon-counting readout chips with smaller pixels and higher frame rates and pixellated avalanche photodiodes for time-resolved experiments.

Optimisation of a Pump-Controlled Hydraulic System using Digital Displacement Pumps

2021 ◽  
Author(s):  
L. Viktor Larsson ◽  
Robert Lejonberg ◽  
Liselott Ericson
Keyword(s):  
Electric Motor ◽  
Energy Savings ◽  
High Energy ◽  
Motor Speed ◽  
Efficient Operation ◽  
Pump Speed ◽  
Hardware Configuration ◽  
Control Optimisation ◽  
And Control ◽  
Parasitic Components

When electrifying working machines, energy-efficient operation is key to maximise the use of the limited capacity of on-board batteries. Previous research indicate high energy savings by means of component and system design. In contrast, this paper focuses on how to maximise energy efficiency by means of both design and control optimisation. Simulation-based optimisation and dynamic programming are used to find the optimal electric motor speed trajectory and component sizes for a scooptram machine equipped with pump control, enabled by digital displacement pumps with dynamic flow sharing. The results show that a hardware configuration and control strategy that enable low pump speed minimise drag losses from parasitic components, partly facilitated by the relatively high and operation point-independent efficiencies of the pumps and electric motor. 5–10% cycle energy reductions are indicated, where the higher figure was obtained for simultaneous design and control optimisation. For other, more hydraulic-intense applications, such as excavators, greater reductions could be expected.

A Review of Switched Inertance Hydraulic Converter Technology1

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Chenggang Yuan ◽  
Min Pan ◽  
Andrew Plummer
Keyword(s):  
Energy Efficient ◽  
High Speed ◽  
Control Strategies ◽  
New Technology ◽  
High Energy ◽  
Hydraulic Power ◽  
Controlled Systems ◽  
Hydraulic Machines ◽  
And Control ◽  
High Speed Switching

Abstract Digital hydraulics is a new technology providing an alternative to conventional proportional or servovalve-controlled systems in the area of fluid power. Digital hydraulic applications, such as digital pumps, digital valves and actuators, switched inertance hydraulic converters (SIHCs), and digital hydraulic power management systems, promise high-energy efficiency and less contamination sensitivity. Research on digital hydraulics is driven by the need for highly energy efficient hydraulic machines but is relatively immature compared to other energy-saving technologies. This review introduces the development of SIHCs particularly focusing on the work being undertaken in the last 15 years and evaluates the device configurations, performance, and control strategies that are found in the current SIHC research. Various designs for high-speed switching valves are presented, and their advantages and limitations are compared and discussed. The current limitations of SIHCs are discussed and suggestions for the future development of SIHCs are made.

A New Cast Stone Roller Kiln and its Combustion Control Approach

2012 ◽  
Vol 605-607 ◽  
pp. 428-432 ◽  
Author(s):  
Jing Chen ◽  
Ai Jun Luo ◽  
You Xin Yuan ◽  
Chun Xiao ◽  
Wang Lin Wang ◽  
...  
Keyword(s):  
Energy Consumption ◽  
High Speed ◽  
High Energy ◽  
Combustion Control ◽  
Cast Stone ◽  
Roller Kiln ◽  
Control Approach ◽  
Control Scheme ◽  
Dense Distribution ◽  
High Energy Consumption

The domestic cast stone industrial production is of high energy consumption and low productivity, so a new cast stone roller kiln is firstly developed. A combustion control approach is advanced to accommodate the new roller kiln architecture and meet the combustion control requirements. Continuous proportion and pulse control methods are adopted to the high-speed isothermal burners with internal dense distribution. Two controllers mutually collaborated in pairs to obtain the internal uniform temperature. The implementation of the combustion control scheme is put forward. The application results demonstrated that the new roller kiln and combustion controller could effectively decrease the furnace temperature difference, increase stability of the combustion atmosphere, improve product quality, reduce energy consumption and NOx emissions.

Study of Flow Characteristics and Control Circuit on High-Speed Solenoid Valve

2012 ◽  
Vol 619 ◽  
pp. 107-110 ◽  
Author(s):  
Wen Hua Li ◽  
Wen Lin Shao
Keyword(s):  
High Speed ◽  
Flow Characteristics ◽  
Pulse Signal ◽  
Solenoid Valve ◽  
Control Circuit ◽  
Duty Ratio ◽  
Time Sharing ◽  
Small Current ◽  
Wide Range ◽  
And Control

Through the analysis of the flow characteristics of the high-speed solenoid valve, the conclusions that the PWM signal duty ratio is the main factor affecting the solenoid valve flow is obtained, a new available any PWM pulse signal and control circuit are proposed. Further, circuit schematic is simulated by means of SIMULINK tools in MATLAB environment and Verify its stability. A time-sharing drive circuit is design based on the PWM drive mode. The driver circuit have function which is high-current open, small current maintain. Open current and maintain current of Solenoid valve can be adjusted through this circuit. Therefore, the circuit can adapt to different parameters of the solenoid valve. A wide range of applications.

Dynamic Analysis and Control of High Speed and High Precision Active Magnetic Bearings

1992 ◽  
Vol 114 (4) ◽  
pp. 623-633 ◽  
Author(s):  
K. Youcef-Toumi ◽  
S. Reddy
Keyword(s):  
Time Delay ◽  
High Speed ◽  
Dynamic Stiffness ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Successful Operation ◽  
Highly Nonlinear ◽  
Wide Range ◽  
And Control ◽  
Digital Time

The successful operation of actively controlled magnetic bearings depends greatly on the electromechanical design and control system design. The function of the controller is to maintain bearing performance in the face of system dynamic variations and unpredictable disturbances. The plant considered here is the rotor and magnetic bearing assembly of a test apparatus. The plant dynamics consisting of actuator dynamics, rigid rotor dynamics and flexibility effects are described. Various components of the system are identified and their corresponding linearized theoretical models are validated experimentally. Tests are also run to identify the coupling effects and flexibility modes. The highly nonlinear behavior of the magnetic bearings in addition to the inherent instability of such a system makes the controller design complex. A digital Time Delay Controller is designed and its effectiveness evaluated using several simulations based on linear and nonlinear models for the bearing including bending mode effects. This controller is implemented as an alternative to an existing linear analog compensator. Several experiments are conducted with each controller for spinning and nonspinning conditions. These include time responses, closed loop frequency responses and disturbance rejection responses. The experimental results and comparisons between those of a digital Time Delay Controller and an analog compensator indicate that the Time Delay Controller has impressive static and dynamic stiffness characteristics for the prototype considered. The Time Delay Controller also maintains almost the same dynamic behavior over a significantly wide range of rotor speeds.

scholarly journals PROPOSING A SYSTEMATIC METHOD FOR CREATING AN ENERGY AUDIT TOOLKIT FOR COPRA PROCESSING ENTERPRISES

2011 ◽  
Vol 14 (3) ◽  
pp. 39-49
Author(s):  
Thanh Van Tran ◽  
Ha Thi Ngoc Ho ◽  
Hai Thanh Le
Keyword(s):  
Energy Efficiency ◽  
Energy Savings ◽  
High Energy ◽  
Energy Audit ◽  
Pilot Projects ◽  
Self Assessment ◽  
Systematic Method ◽  
Processing Industry ◽  
Production Processes ◽  
High Energy Consumption

Coconut processing is one of a typical industral sector of Ben Tre Province. Due to the high energy consumption chaterization, it has been selected to perform the pilot projects of promoting cleaner production and energy efficiency. Energy audit is a suggested measure to identifine opportunities and solutions for energy savings. However it is quite an expertise-demanding and timeconsuming procedure, therefore still a few number of plants have applied energy audit for their production processes. For all those reasons, there is a need of an automatic energy audit toolkit which can help enterprises in self–assessment of the energy using and performing of energy saving measures. This reseach aims at proposing a systematic method for creating an energy audit toolkit for copra processing enterprises which is expected to be a development initiative for coconut processing industry.

The Critical Pressure at the Onset of Flame Instability of Syngas/Air/Diluent Outwardly Expanding Flame at Different Initial Temperatures and Pressures

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Ziyu Wang ◽  
Ziwei Bai ◽  
Guangying Yu ◽  
Sai Yelishala ◽  
Hameed Metghalchi
Keyword(s):  
High Speed ◽  
Critical Pressure ◽  
Hydrodynamic Instability ◽  
Experimental Studies ◽  
Initial Pressure ◽  
High Energy ◽  
Oxide Semiconductor ◽  
High Energy Density ◽  
Flame Instability ◽  
Wide Range

Syngas has gained attention recently due to its high energy density and environmentally friendly characteristics. Flame stability plays an important role in flame propagation in energy conversion devices. Experimental studies were performed in a cylindrical chamber to investigate flame instability of syngas/air/diluent mixture. A Z-shape Schlieren system coupled with a high-speed complementary metal–oxide–semiconductor camera was used to record flame pictures up to 40,000 frames per second. In this research, syngas is a mixture of hydrogen and carbon monoxide and diluent is a blend of 14% CO2 and 86% N2 with the same specific heat as the burned gases. Three main flame instabilities namely Rayleigh–Taylor (body force) instability, hydrodynamic instability, and thermal-diffusive instability have been studied. For the onset of flame instability, a power law correlation for the ratio of critical pressure to initial pressure of syngas/air/diluent flames over a wide range of initial temperatures (298–450 K), initial pressures (1.0–2.0 atm), equivalence ratios (0.6–3.0), diluent concentrations (0–10%), and hydrogen percentages (5–25%) in the fuel has been developed.

MICROSTRUCTURE AND FUNCTIONAL PROPERTY CHANGES IN THIN Ni–Ti WIRES HEAT TREATED BY ELECTRIC CURRENT — HIGH ENERGY X-RAY AND TEM INVESTIGATIONS

2009 ◽  
Vol 02 (02) ◽  
pp. 45-54 ◽  
Author(s):  
B. MALARD ◽  
J. PILCH ◽  
P. SITTNER ◽  
V. GARTNEROVA ◽  
R. DELVILLE ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Electric Current ◽  
High Energy ◽  
X Ray ◽  
Transmission Electron ◽  
Conventional Heat Treatment ◽  
Wide Range ◽  
Millisecond Range ◽  
Property Changes ◽  
Evolution Of Microstructure

High energy synchrotron X-ray diffraction, transmission electron microscopy and mechanical testing were employed to investigate the evolution of microstructure, texture and functional superelastic properties of 0.1 mm thin as drawn Ni – Ti wires subjected to a nonconventional heat treatment by controlled electric current (FTMT-EC method). As drawn Ni – Ti wires were prestrained in tension and exposed to a sequence of short DC power pulses in the millisecond range. The annealing time in the FTMT-EC processing can be very short but the temperature and force could be very high compared to the conventional heat treatment of SMAs. It is shown that the heavily strained, partially amorphous microstructure of the as drawn Ni – Ti wire transforms under the effect of the DC pulse and tensile stress into a wide range of annealed nanosized microstructures depending on the pulse time. The functional superelastic properties and microstructures of the FTMT-EC treated Ni – Ti wire are comparable to those observed in straight annealed wires.

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