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Large nonlinear deflection behavior of IPMC actuators analyzed with an electromechanical model

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Acta Mechanica Sinica 2019年第5期35卷 992-1000页

作者： H.G.Liu K.Bian K.Xiong Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou 510006China

This study presents an electromechanical engineering model for the analysis of the large deflection curves of ionic polymer-metal composite(IPMC)cantilever actuators under direct current(DC)voltages.In this paper,the longitudinal normal strain performance of the material was investigated using digital image correlation on a micro-scale.The deflection of the actuator is analytically obtained with the application of an elliptic integration method based on the relationship between strain gradient and excitation voltage,and the minimum excitation voltage is derived based on the assumption that the actuators have small deformations.The validity of the electromechanical model is then justified with the experimental results obtained from Pt-and Ag-IPMC actuators at various excitation voltages.The findings of this study confirm that the introduced electromechanical model can accurately describe the large nonlinear deflection behavior of IPMC actuators.

关键词： Actuator Ionic polymer metal composite Large deflection electromechanical model

THE EFFECTIVE electromechanical PROPERTIES OF CELLULAR PIEZOELECTRET FILM:FINITE ELEMENT MODELING

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Acta Mechanica Solida Sinica 2013年第1期26卷 1-8页

作者： Yongping Wan Liangliang Fan Zheng Zhong School of Aerospace Engineering and Applied Mechanics Tongji University

Cellular space-charge polymer film, also called cellular piezoelectret, has very large piezoelectric effect due to their unique microvoid structure. In this article, the cellular piezoelectret film is considered to be a periodic composite material with closed-cell microvoids aligned periodically. Three dimensional finite element modeling is carried out to obtain the effective elastic modulus and piezoelectric coefficients. Sensitivity analysis was presented by modeling the effec- tive electromechanical properties with different individual variable, including material constants and void shape parameters. By assuming a relation between void shape and void volume fraction, the finite element model can simulate quite well the inflation experiments of the voided charged Polypropylene film published in literature. Finally, the finite element model is used to explore the voided charge polymer film with non-uniform distribution of the trapped charges on the internal surface of voids. It was found that the resultant overall piezoelectric coefficients will be more significant if charges are closely gathered in the central area, and sparse in the around area of the internal surface of voids.

关键词： piezoelectret electromechanical finite element methods

Early faults prediction of running state of electromechanical systems and reconfigurable integration of series safety monitoring systems

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仪器仪表学报 2014年第S2期35卷 224-232页

作者： Xu Xiaoli Zuo Yunbo Chen Tao Liu Xiuli Chen Shanpeng Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing Information Science and Technology University School of Mechanical and Vehicle Engineering Beijing Institute of Technology Department of Environmental Science and Engineering Faculty of Bioresources Mie University

Fault prediction technology of running state of electromechanical systems is one of the key technologies that ensure safe and reliable operation of electromechanical equipment in health state. For multiple types of modern, high-end and key electromechanical equipment, this paper will describe the early faults prediction method for multi-type electromechanical systems, which is favorable for predicting early faults of complex electromechanical systems in non-stationary, nonlinear, variable working conditions and long-time running state; the paper shall introduce the reconfigurable integration technology of series safety monitoring systems based on which the integrated development platform of series safety monitoring systems is built. This platform can adapt to integrated R&D of series safety monitoring systems characterized by high technology, multiple species and low volume. With the help of this platform, series safety monitoring systems were developed, and the Remote Network Security Monitoring Center for Facility Groups was built. Experimental research and engineering applications show that: this new fault prediction method has realized the development trend features extraction of typical electromechanical systems, multi-information fusion, intelligent information decision-making and so on, improving the processing accuracy, relevance and applicability of information; new reconfigurable integration technologies have improved the integration level and R&D efficiency of series safety monitoring systems as well as expanded the scope of application; the series safety monitoring systems developed based on reconfigurable integration platform has already played an important role in many aspects including ensuring safety operation of equipment, stabilizing product quality, optimizing running state, saving energy consumption, reducing environmental pollution, improving working conditions, carrying out scientific maintenance, advancing equipment utilization, saving maintenance charge and enhancing the level of informati

关键词： electromechanical systems early faults safety control monitoring systems reconfigurable integration

Study on electromechanical coupling nonlinear vibration of flywheel energy storage system

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Science China(Technological Sciences) 2006年第1期49卷 61-77页

作者： JIANG Shuyun JU Lihua Department of Mechanical Engineering Southeast University Nanjing 210096 China Department of Mechanical Engineering Southeast University Nanjing 210096 China

The electromechanical coupling dynamics of the flywheel energy storage system (FESS) with a hybrid permanent magnetic-dynamic spiral groove bearing has been studied. The functions of the kinetic energy, the potential energys, the magnetic field energy in air gap of the flywheel motor and the energy dissipation of the whole system were obtained, and the differential equations set with electromagnetic parameters of FESS was established by applying the extended Lagrange-Maxwell equation. The four-order implicit Runge-Kutta formula to the equations was derived, and the nonlinear algebraic equations were solved by using the Gauss-Newton method. The analytical solution of an example shows that the upper damping coefficient, the lower damping coefficient and the residual magnetic induction of the rare earth permanent magnet play an important role in electromechanical resonance of the flywheel rotor system. There is a small change for the electromechanical coupling resonance frequency with the upper damping coefficient in-creasing, but the resonance amplitude decreases with the upper damping coefficient in-creasing. With the lower damping coefficient increasing, the resonance frequency in-creases, and the resonance amplitude decreases. With the residual magnetic induction of the permanent magnet increasing, the resonance frequency decreases, and the reso-nance amplitude increases.

关键词： flywheel energy storage system, hybrid permanent magnetic-dynamic spiral groove bearing, electromechanical coupling dynamics, Lagrange-Maxwell equation.

The Analysis of the Differences between electromechanical Transients Simulation and Electromagnetic Transients Simulation

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Journal of Power and Energy Engineering 2014年第9期2卷 139-146页

作者： Chengjun Xia Haoyu Huang Kun Men Cuiqiong Chen School of Electric Power South China University of Technology Guangzhou China Electric Power Research Institute of CSG China Southern Power Grid Guangzhou China

The paper firstly interprets the differences between electromechanical transients program BPA and electromagnetic transients program EMTDC in the field of principle, model and algorithm. Then the authors carry out the simulation based on single-machine infinite-bus system and draw some conclusions. The time consumption of the simulation using EMTDC is much longer than the simulation using BPA under the same length of time. The results of BPA are close to those of EMTDC under steady conditions. The fundamental frequency component of the EMTDC results seems closer to the BPA results than its original value, but they still away from completely consistent. In this simulation of single-machine infinite-bus system, the transient stability results of BPA and EMTDC are close, but the results of BPA are apt to be more conservative. All the conclusions above have a certain reference value to both hybrid simulation and comprehensive analysis method in the study of the AC/DC digital simulation of large power grid.

关键词： Electromagnetic Transients electromechanical Transients Simulation Difference

The Change and Prospect of “Automobile electromechanical Maintenance Skills Competition” under the Chinese Model

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Journal of Mechanical Engineering Research 2019年第2期2卷 8-13页

作者： Jianguo Feng Sichuan Vocational And Technical College of Communications chengdusichuan611130China

This paper analyzes the origin, status, changes and characteristics of theautomotive electromechanical maintenance skills competition in China,and presents the developing trend in the future.

关键词： Automobile electromechanical maintenance Skill contest Change Development

Simulation Study on electromechanical Disturbance Propagation in Large Power System

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Journal of Power and Energy Engineering 2015年第4期3卷 155-161页

作者： Changyong Chen Bowei Hu Xiaoru Wang School of Electrical Engineering Southwest Jiaotong University Chengdu China

Power systems are subjected to all kinds of random disturbances, showing the electromechanical dynamic. A lot of theoretical researches show that the disturbance power and frequency is propagating in the form of wave which is called electromechanical wave. But electromechanical wave theory is not widely used in actual power system. In this paper we focus on simulation study of electromechanical wave frequency sensitivity and propagation velocity and elaborating the simulation results with the electromechanical wave theory. Finally some summaries and expectations on electromechanical wave study are made.

关键词： electromechanical Wave Power System Simulation Study Frequency Sensitivity Propagation Velocity

Promoting New Pattern of Jiangxi Marine electromechanical Industry Development

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船舶经济贸易 2019年第8期 74-76页

作者： Zhang Liying Xiang Zhao CSSC Jiujiang Marine Equipment (Group) Co. Ltd.

Shipbuilding industry is the traditional pillar industry of Jiangxi province. Under the background of the continuous downward trend of economic indicators for the national shipbuilding industry, especially the sharp decline in global demand for new ships, domestic orders for new ships and handheld ship orders have dropped at this stage compared with the same period last year, and under the background that the problems such as “financing difficulties” and “receiving order difficulties” in the shipbuilding industry have not been alleviated, in recent years, the shipbuilding industry enterprises in the province have taken measures such as actively responding, strengthening planning first, dislocation competition, lean management, diversified operation, and so on.

关键词： New Pattern Jiangxi Marine electromechanical Industry

The Precise Determination of Mass through the Oscillations of a Very High-Q electromechanical System

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Journal of Electromagnetic Analysis and Applications 2013年第3期5卷 91-95页

作者： Osvaldo F. Schilling Department of Physics (CFM/FSC) Federal University of Santa Catarina (UFSC) 88040-900 Florianópolis Brazil.

The present paper is based upon the fact that if an object is part of a highly stable oscillating system, it is possible to obtain an extremely precise measure for its mass in terms of the energy trapped in the system, rather than through a ratio between force and acceleration, provided such trapped energy can be properly measured. The subject is timely since there is great interest in Metrology on the establishment of a new electronic standard for the kilogram. Our contribution to such effort includes both the proposal of an alternative definition for mass, as well as the description of a realistic experimental system in which this new definition might actually be applied. The setup consists of an oscillating type-II superconducting loop subjected to the gravity and magnetic fields. The system is shown to be able to reach a dynamic equilibrium by trapping energy up to the point it levitates against the surrounding magnetic and gravitational fields, behaving as an extremely high-Q spring-load system. The proposed energy-mass equation applied to the electromechanical oscillating system eventually produces a new experimental relation between mass and the Planck constant.

关键词： Mass Magnetic Levitation electromechanical Oscillations