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The level of electromagnetic radiation (EMR) exposure increases day by day as natural consequences of technological developments. In recent years, the increasing use of cellular systems has made it necessary to measure and evaluate EMR originating from base stations. In this study, broadband and band selective electric field strength (E) measurements were taken at four different times in order to...
Accurate localization techniques applicable to indoor environments become more and more important for the development of advanced location aware applications, such as for example: in-building guidance, asset tracking in hospitals or warehouses and autonomous robot navigation [1].
In this paper the pareto front of flux reversal machines regarding torque, torque-ripple and normal forces is determined. For this reason a fast, but accurate, analytical calculation method is provided. An optimization procedure is given to realize an optimal design for each topology.
The hysteresis motor produces the torque by magnetic hysteresis. The overexcitation for a short period of the hysteresis motor running at synchronous speed reduces the stator current and increases the pull-out torque at the same time. This excellent effect after one-time overexcitation lasts theoretically forever. However, the sudden changes of stator voltage or load torque reduce and vanish it. The...
Field-circuit model of a brushless DC motor with speed control using PWM method was developed. Waveforms of electrical and mechanical quantities of the designed motor in which high-pressure, inverted action vane pump is built in were computed.
Electrostatic adhesion force is studied and analysed with emphasis on design parameters of the interdigital electrodes, material properties of dielectric layers and its thickness. From these results two fabrication processes of the electroadhesive foils are studied to reach the highest possible performance. Experimental measurements are carried out to verify the results.
The paper deals with a single-phase induction machine operating as a stand-alone self-excited single-phase induction generator for generation of electrical energy from renewably energy sources. By changing number of turns and size of wires in the auxiliary stator winding, considerable improvement of performance characteristics of the generator were obtained as regards no-load and load voltage of the...
In the paper an algorithm and software fors optimization of the magnetostrictive actuator, taking the dynamic parameters into account is presented. The device is applied as a drive for plasma valve and is characterised by very short time of operation. The structure with cylindrical core and cylindrical exciting winding supplied with discharging capacitor current pulses is designed. The field-circuit...
The paper attempts to determine the impact of fuel impurities on the value of fuel energy spark discharge and the wear of spark plug electrode. Spark plugs were analyzed in two typical configurations of the ignition system. For the analyzed systems, a number of tests to determine the wear of spark plug electrode subjected to different types of impurities were conducted. The value of spark discharge...
Electric motors have broad applications in the industrial sector such as water and waste-water pumps, compressors, funs and others. They use about 30%–80% of total industrial energy around the world (e.g. it is expected that 62,500 GWh electricity, or 56% of total output of electricity in Poland, is used to drive equipment). Therefore the cost of energy to operate motors has become a real concern...
In this paper a machine learning algorithm was applied to analyze the integrated data responses of magnetic multi-sensor matrix transducer. In order to proceed the algorithm, a large database was prepared considering measurement as well as simulation results. A finite element method was utilized to conduct a numerical calculation and provide transducers response signals for the various configurations...
Doubly fed induction generators (DFIGs) are the most common wind energy systems that are used in high-power applications. DFIG control system depends on system parameters identification. Detection or estimation of electromagnetic flux of the rotor and stator are necessary for control of DFIG back to back converter. In this paper, the role of electromagnetic flux of rotor and stator on controlled of...
This paper presents speed control studies of induction motor by 6-switched 3-level inverter. In topology, the field oriented control technique used which is widely used in the literature, easy and stable for operating systems. The field weakening technique done for exceed speeds to nominal speed to reduce magnetic saturation and thermal losses. End of the process, it has been observed to increase...
The paper presents some results of study of the electric and thermal processes, taking part in contact resistance welding of cross-wire steel bars. The investigations are based on 3D FEM modeling of the electric and temperature field distribution. Several successive stages of the welding process are considered in the study, taking into account the changes, corresponding to the increase of the contact...
The paper presents an analysis of influence of selected fault states on properties of brushless DC motor with permanent magnets. The subject of study was BLDC motor designed by the authors for unmanned aerial vehicle hybrid drive. Four parallel branches per each phase were provided in the discussed 3-phase motor. After open-winding fault in single or few parallel branches, a further operation of the...
In the paper authors proposed an analysis of the distribution of temperatures around electroconductive pathways createded on flexible textile substrates used in elastic electronics and also in textronics. The research was based on the thermographic photographs of the produced samples. The analysis was carried out using the Image ThermaBase EU software.
In the paper the authors describe the research on thin-film surface heat sources created on flexible textile substrate. The novelty of research is included in using two technologies: physical vapour deposition and laser ablation. Two structures in form of meander and clover were implemented in Comsol Multihysics package to laser ablation optimization and to modeling of structure heating. Experiments...
The paper deals with the analysis of electromagnetic phenomena in a two-winding permanent magnet synchronous generator (PMSG) driven by wind turbines. The machine's winding is designed to facilitate application of a low cost and reliable AC/DC power electronic converter. The finite element method has been employed to develop numerical models for the case study problem of the machines. Special attention...
In the paper, sudden short-circuit transients at terminals of an autonomous single-phase induction generator were simulated using field-circuit 2D model of the single-phase induction generator. The transients at terminals were calculated for different configurations of capacitors in stator windings. Some experimental results showing re-excitation of the stator voltage after sudden short-circuit at...
The mathematical model for temperature field analysis of the new hybrid magnetic bearing has been presented in the paper. The distributions of temperature which have been obtained from 2D and 3D simulations were compared with the results from the physical model testing of the hybrid bearing.
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