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International Siberian Conference on Control and Communications

作者： Jaroslav Hlava Nikita Zemtsov Galina Frantsuzova Institute of Mechatronics and Computer Engineering Faculty of Mechatronics Informatics and Interdisciplinary Studies Technical university of Liberec Liberec Czech Republic Automatics Department Faculty of Automation and Computer Engineering Novosibirsk State Technical University Novosibirsk Russian Federation

ISBN: (纸本)9781467383844

The work deals with usage of classical PID controller to maintain balance between electricity consumption and production using concepts of smart grid and virtual power plant. Aggregated control of large groups of thermostatically controlled loads can be used for ancillary services provision. The focus is on secondary control and peak-shaving, which are a part of the power balance problem. Calculation of PID controller parameters are based on the localization method. The main idea of the localization method is using a derivatives vector of the controlled variable for manipulated variable calculation. The highest derivative implicitly contains full information about plant's state at the current moment. The dynamics of individual building with heaters is described by second order equivalent thermal parameters (ETP) model. The obtained results show that aggregate response of large population of electrical space heaters can meet the requirements on both of the problems. Nevertheless, there are still a lot of issues remaining open: influence of the hysteresis parameter, and using suitable sampling time in order to lower demand on the communication infrastructure.

关键词： smart grid power balance PID controler localization method secondary control peak shaving thermostatically controlled load aggregate modelling equivalent thermal parameters model

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Testing methods of pressure distribution of bra cups on breasts soft tissue

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IOP Conference Series: Materials Science and engineering 2017年第14期254卷

作者： B Musilova R Nemcokova M Svoboda Technical University of Liberec Faculty of Textile Engineering Department of Clothing Technology Studentská 1402/2 461 17 Liberec Czech Republic Technical University of Liberec Faculty of Mechatronics Informatics and Interdisciplinary Studies Institute of Mechatronics and Computer Engineering Studentská 1402/2 461 17 Liberec Czech Republic

Objective of this study is to evaluate testing methods of pressure distribution of bra cups on breasts soft tissue, the system which do not affect the space between the wearer's body surface and bra cups and thus do not influence the geometry of the measured body surface and thus investigate the functional performance of brassieres. Two measuring systems were used for the pressure comfort evaluating: 1) The pressure distribution of a wearing bra during 20 minutes on women's breasts has been directly measured using pressure sensor, a dielectricum which is elastic polyurethane foam bra cups. Twelve points were measured in bra cups. 2) Simultaneously the change of temperature in the same points bra was tested with the help of noncontact system the thermal imager. The results indicate that both of those systems can identify different pressure distribution at different points. The same size of bra designing features bra cups made from the same material and which is define by the help of same standardised body dimensions (bust and underbust) can cause different value of a compression on different shape of a woman´s breast soft tissue.

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Convergence rate of the modified differential evolution algorithm

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AIP Conference Proceedings 2017年第1期1910卷

作者： Roman Knobloch Jaroslav Mlynek Radek Srb 1Department of Mathematics FP Technical University of Liberec Studentska 2 461 17 Liberec The Czech Republic 2)Institute of Mechatronics and Computer Engineering Technical University of Liberec Studentska 2 461 17 Liberec The Czech Republic

Differential evolution algorithms represent an efficient framework to solve complicated optimization tasks with many variables and complex constraints. Nevertheless, the classic differential evolution algorithm does not guarantee the convergence to the global minimum of the cost function. Therefore, the authors developed a modification of this algorithm that ensures asymptotic global convergence. The article provides a comparison of the ability to identify the global minimum of the cost function for the following three algorithms: the classic differential evolution algorithm, the above mentioned modified differential evolution algorithm and an algorithm of random sampling enhanced by a hill climbing procedure. We designed a series of numerical experiments to perform this comparison. The results indicate that the classic differential evolution algorithm is in general an extremely poor global optimizer (global minimum found in 2% of cases). On the other hand the performance of the modified differential evolution algorithm was considerably better (global minimum found in 83% of cases).

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Frequency response of selected current transformes and hall-effect current sensors 21

Frequency response of selected current transformes and hall-...

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21st IMEKO World Congress on Measurement in Research and Industry

作者： Schreiber, Richard Sikorová, Iveta Institute of Mechatronics and Computer Engineering Faculty of Mechatronics Informatics and Interdisciplinary Studies Technical University of Liberec Liberec Czech Republic

This paper is dealing with the comparison of isolated current sensors of nominal value up to 200 A. Emphasis is placed on the operation of the sensors at very low frequencies, where the amplitude and phase error is evaluated. This research was needed for the choice of an optimal current sensor for the development of a diagnostic system for induction motors. The most suitable sensors in the terms of performance and cost are selected in accordance with the application.

关键词： Hall effect

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Flicker and driver topology assessment of Extra Low Voltage LED lamps under DC supply

Flicker and driver topology assessment of Extra Low Voltage ...

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International Conference on Harmonics and Quality of Power

作者： Leoš Kukačka Jiří Drápela Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec Czech Republic Department of Electrical Power Engineering Brno University of Technology Brno Czech Republic Université de Toulouse LAPLACE UMR 5213 (CNRS INPT UPS) Toulouse France

This paper addresses the flicker of LED lamps designed for ELV supply. In the first part the severity of the produced flicker under DC supply is measured in two connection modes - with and without the rectifying bridge - in order to investigate influence on lamps sensitivity to sinusoidal and rectangular amplitude modulation of the supply voltage. Second part of the paper introduces an approach to estimate the lamps' flicker response to non-harmonic supply voltage distortion based on the flicker caused by harmonic supply voltage distortion. The approach is demonstrated upon the tested lamps and its limitations are discussed.

关键词： Voltage measurement Frequency modulation LED lamps Indexes Voltage fluctuations

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Simple analysis and use of preisach model for ferromagnetic materials

Simple analysis and use of preisach model for ferromagnetic ...

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IEEE International Workshop of Electronics, Control, Measurement, Signals and their application to mechatronics (ECMSM)

作者： Jakub Eichler Miloslav Košek Miroslav Novák Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec

Because of hysteresis the perfect modeling of ferromagnetic materials is difficult. The general purpose of Preisach model was applied in this area. The main problem is to determine the weighting function from measurement of hysteresis loops. Another approach, based on the method of trials and errors, was used. According to the nature of a material, the weighting function was searched in the form of normal distribution with constant background. Only several parameters should be found by the best fit with experimental data. The agreement with experiment is acceptable, especially for higher excitations. The numerical model can be used for semi quantitative analysis or simulation of electrical or electronic devices with a ferromagnetic core.

关键词： Magnetic hysteresis Mathematical model Hysteresis Magnetic fields Magnetic domains Magnetic moments Computational modeling

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Influnce of driving style of a tram driver on the tram's energy consumption 18

Influnce of driving style of a tram driver on the tram's ene...

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18th International Conference on Electrical Drives and Power Electronics, EDPE 2015

作者： Kubín, Jiří Ferková, Želmíra Institute of Mechatronics and Technical Informatics Technical University of Liberec Studentská 2 Liberec461 17 Czech Republic Dept. of Electrical Engineering and Mechatronics Technical University of Kośice Letná 9 Kośice042 00 Slovakia

ISBN: (纸本)9781467373760

A typical feature of city tram transportation is increasing its effectivity. The main effort of public transportation companies is seeking savings for decreasing the energy intensity of mass transit. During operative measurement of power consumption in the tram cars it was found that on the whole the tram energy consumption have well-known influences such as tram occupancy, use of heating etc., and less known factors such as e.g. driving style of driver. We would like to estimate how much more energy is consumed by aggressive driving style of driver. Because it is impossible to ensure the same conditions at passing the same track, we concentrated on devising a tram car model that quantifies the difference of consumed energy in case normal driving style of the driver and in case of dynamic driving style of the driver. Because we use mathematical model, we can set the other conditions such as vehicle occupancy, the number of accelerations, stoppings etc. on the same values. © 2015 IEEE.

关键词： Energy utilization

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Tomographical approach in 3-D temepearture distribution measurement by digital holography 21

Tomographical approach in 3-D temepearture distribution meas...

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21st IMEKO World Congress on Measurement in Research and Industry

作者： Psota, Pavel Doleček, Roman Lédl, Vít Vojtíšek, Petr Vít, Tomáš Matoušek, Ondřej Institute of Plasma Physics Academy of Sciences of the Czech Republic Praha Czech Republic NTI Faculty of Mechatronics Technical University of Liberec Liberec Czech Republic KEZ Faculty of Mechanical Engineering Technical University of Liberec Liberec Czech Republic

A digital holographic method for 3-D measurement of temperature distribution is introduced in this paper. It is based on digital holographic tomography employing only one digital camera. The method is applied for measurement of steady naturally convective flow of fluid and as well as for fast dynamic flow in the form of pulsatile jets of fluid.

关键词： Temperature measurement

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Nonlinear model predictive control of the steam superheating - unmeasured disturbance suppression

Nonlinear model predictive control of the steam superheating...

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International Conference on Process Control (PC)

作者： J. Opalka L. Hubka The Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec Czech Republic

This paper deals with the nonlinear model predictive control of the superheated steam temperature in the power plant once-through boiler. Particularly the controller response on impulse of unmeasured disturbance in the form of flue gas heat is investigated. The two different nonlinear predictive controllers are described in the paper. The feedback of the first controller is closed by nonlinear open loop observer with correction for offset free reference tracking. The second controller works with the close loop state and unmeasured disturbance observer based on the nonlinear moving horizon algorithm. Responses of these two controllers and response of the original controller based on the adaptive PID are compared.

关键词： Power generation Observers Temperature measurement Boilers Load modeling

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Additional internal speed feedback loop for servomechanism residual vibration active damping

Additional internal speed feedback loop for servomechanism r...

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Asian Control Conference

作者： David Lindr Martin Kysela Institute of Mechatronics and Computer Engineering Technical University of Liberec Liberec Czech Republic

This paper describes an alternative approach for an residual vibration active damping of special types of servomechanism. The main idea of this method is to generate an additional speed setpoint by means of an internal motor speed signal (as a carrier of residual vibration). By means of weighting and phase shifting, the compensation signal is adjusted into an appropriate scale and phase and returned back into the drive control structure. This method was successfully implemented into the conventional drive control system and its damping effect proven experimentally.

关键词： Vibrations Damping Servomechanisms Feedforward neural networks Shafts Robustness

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