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This review addresses the use of computational electromagnetics (CEM) in solving electromagnetic compatibility (EMC) problems. Issues such as, multi-scale modelling, the use of macro-models, time-domain and frequency-domain models, the use of structured and un-structured meshes and stochastic modelling will be addressed to give a broad overview of the state of the art and future prospects in this...
Practical applications create requirements on different methods for Computational Electromagnetics. A couple of these methods are compared in this paper and their suitability for low and high frequencies is particularly highlighted.
Technological advancements have driven the humanity for the past five decades. In many of these technological advances, computational electromagnetics has played a major role. From the design of aeroplanes down to consumer electronics, the field of computational electromagnetics has been growing steadily in terms of maturity, complexity, as well as performance. However, innovation does not seem to...
When starting the discussion of High Frequency (HF) problems, we first need to define what our scope of interest is. For example, 1 MHz is a high frequency for power engineers but a rather low frequency for microwave specialists. In electromagnetic simulations we will consider as HF those frequencies, for which the size of the analysed object is comparable to the wavelength. It is difficult to set...
The paper deals with coupled electromagnetic, hydrodynamic, thermal and mechanical motion phenomena in magnetorheological fluid actuators. The governing equations of these phenomena are presented. The numerical implementation of the mathematical model is based on the finite element method and a step-by-step algorithm.
This paper is concerned with the current state of optimisation in the area of electromagnetic device design. It reviews existing methods and discusses multi-objective problems and the effect of parameter uncertainties.
In this paper, an hybrid parallelisation approach for the simulation of nonlinear electromagnetic problems by means of the Message Passing Interface (MPI) and the OpenMP Application Program Interface for the Finite Element Method (FEM) is investigated. After an introduction, the metrics applied to evaluate the speedup and the efficiency are outlined. By parallelising the institute's in-house FEM-package...
This paper describes a novel parametric approach to the simulation of circular aperture transfer functions in the presence of obscurations at microwave frequencies. A novel virtual ‘absorbing box’ power loss integration technique is applied to successfully demonstrate its validity for conditions where the aperture diameter approaches one tenth of the plate largest dimension.
In this paper, a few practical pieces of advice for implementing a 3D FDTD algorithm in the OpenCL library are presented. The efficiency of the methods shown is tested by comparing performance of OpenCL 3D FDTD implementation with standard C/C++ implementation.
This paper presents analytical formulations and 3D finite element calculations for the analysis of effects of the contact resistance between two poorly insulated magnet segments regarding eddy current losses. The calculations deal with low speed large direct drive permanent magnet wind turbine generators. The analytical and finite element results are compared for different contact conductivities....
In this paper, mathematically rigorous R, L circuits of high frequency multi-winding transformers are numerically extracted. Two procedures based on the Finite Element Method (FEM) are investigated. In the first one, a Cholesky decomposition is applied to the resistance and inductance matrices of the device, which are obtained using a FE model. The second approach employs the FEM as a virtual laboratory...
The diagnostics of power transformers is very important in order to plan repairs and replacements of aged population of transformers operated in Poland and Europe. As the Frequency Response Analysis (FRA) is based on comparison of measured curves, which are not always available from previous measurements, the computer modeling was applied to create models of windings' response.
A new type of electromagnetic actuator with high holding force and extremely low consumption of electric energy is proposed and modelled. The movement of its plunger formed by a permanent magnet is controlled by short pulses of direct current together with a return spring. The paper presents the arrangement of the device and analyses its principal operation characteristics.
This work proposes an optimization procedure based on a bootstrapped neural network interpolation approach and the Genetic Algorithm method. The bootstrapped neural network is used to generate designed data sets in order to estimate a mapping from input to output space in an intrinsic experiment in a motor drive vibration study. The optimization procedure is aimed to minimize the motor vibration by...
The present paper proposes a new design of 4-layer 32-electrode cylindrical Electrical Capacitance Tomography (ECT) sensor. The novelty is the proposed hexagonal shape of the electrodes, which ensures more uniform sensitivity in the imaging area. The new sensor is analyzed using Finite Element Method and its sensitivity maps are calculated. It is shown that the new sensor will provide more uniform...
A paper presents a new physical interpretation of equivalent circuit for three phase wye connected winding without neutral wire. In order to formulate this interpretation a set of elementary circuit simplifications is applied. As an example a reluctance motor stator winding is used. The importance of presented idea results from the fact that wye connected stator winding without neutral wire is by...
This paper describes a structure of a typical actuator with magnetostrictive core. Based on equations of modified Jiles-Atherton model, algorithm and computer application for calculation of magnetomechanical hysteresis, distinctive for magnetostrictive transducers were developed. Furthermore, influence of compressive stress on maximum strain were presented.
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