Analysis Of Electromagnetic Phenomena Research Articles

Analysis of electromagnetic phenomena in modulated flux synchronous generator

PurposeThe purpose of this paper is to present the electromagnetic phenomena in permanent magnet synchronous generator (PMSG) suited for wind turbines with uniquely designed system of two windings. The machine’s windings allow for application of a reliable and low-cost power electronic converter.Design/methodology/approachThe 2D field-circuit model has been developed and used in comparative analysis between reference design PMSG with concentrated three-phase winding and two-windings PMSG to facilitate application of a low-cost and reliable AC/DC power electronic converter. The paper focuses on comparison of radial force density, core losses and torque waveforms in the proposed and reference machine with sinusoidal load currents.FindingsThe usefulness of the proposed approach for analysis of the two-winding PMSG performance by means of the field-circuit model has been proved. The obtained results show practically no drop off of performance of proposed machine in relation to reference PMSG. Moreover, it has been shown that both machines are characterized by the same level of radial force density. Therefore, the lower cost and reliable power electronic converts can be applied in the wind power energy systems (WPES) by slightly more complex design of the stator winding.Originality/valueThe proposed 2D field-circuit numerical model makes it possible to analyze the performance of the star-delta winding PMSG dedicated to be loaded by the AC to DC converter specially designed to achieve high reliability and efficiency of the system. Presented comparative studies on generator performance show that proposed modulated synchronous flux generator characterize with the same output torque at given supply current and core losses level like conventional PMSG with sinusoidal load.

Analysis of Electromagnetic Propagation from MHz to THz with a Memory-Optimised CPML-FDTD Algorithm

FDTD method opened a fertile research area on the numerical analysis of electromagnetic phenomena under a wide range of media and propagation conditions, providing an extensive analysis of electromagnetic behaviour like propagation, reflection, refraction, and multitrajectory phenomena. In this paper, we present an optimised FDTD-CPML algorithm, focused in saving memory while increasing the performance of the algorithm. We particularly implement FDTD-CPML method at high frequency bands, used in several telecommunications applications as well as in nanoelectromagnetism. We show an analysis of the performance of the algorithm in single and double precision, as well as a stability of the algorithm analysis, from where we conclude that the implemented CPML ABC constitutes a robust choice in terms of precision and accuracy for the high frequencies herein considered. It is important to recall that the CPML ABC parameters provided in this paper are fixed for the tested range of frequencies, that is, from MHz to THz.

Electromagnetic phenomena analysis in brushless DC motor with speed control using PWM method

Abstract 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 with a high pressure vane pump built in a rotor of the motor were computed. Analysis of electromagnetic phenomena in the system: single phase AC network – converter - BLDC motor was carried out.

Gearing up for Lagrangian dynamics

James Clerk Maxwell’s 1865 paper, “A Dynamical Theory of the Electromagnetic Field,” is usually remembered as replacing the mechanical model that underpins his 1862 publication with abstract mathematics. Up to this point historians have considered Maxwell’s usage of Lagrangian dynamics as the sole important feature that guides Maxwell’s analysis of electromagnetic phenomena in his 1865 publication. This paper offers an account of the often ignored mechanical analogy that Maxwell used to guide him and his readers in the construction of his new electromagnetic equations. The mechanical system consists of a weighted flywheel geared into two independently driven crank wheels in what amounts to a mechanical differential. I will demonstrate how Maxwell made use of the analogy between his flywheel system and electromagnetic induction to ground his study of electromagnetism in clear mechanical conceptions and to structure the derivation of the equations that together are now recognized as Maxwell’s equations for electrodynamics. By reconceiving specific components of his model in electromagnetic terms, while at the same time retaining many of the relations between concepts in the mechanical case, Maxwell gradually assembled increasingly generalized equations for electromotive force. Maxwell thus realized a much sought after balance between physical analogy and abstract mathematics in this, the last of his three seminal papers on electromagnetism.

Efficient Parallel Preconditioned Conjugate Gradient Solver on GPU for FE Modeling of Electromagnetic Fields in Highly Dissipative Media

We present a performance analysis of a parallel implementation of preconditioned conjugate gradient solvers using graphic processing units with compute unified device architecture programming model. The solvers were optimized for the solution of sparse systems of equations arising from finite-element analysis of electromagnetic phenomena involved in the diffusion of underground currents in both steady state and under time-harmonic current excitation. We used both shifted incomplete Cholesky factorization and incomplete LU factorization as preconditioners. The results show a significant speedup using the graphics processing unit compared with a serial CPU implementation.

GPU-based LU decomposition for large method of moments problems

In the method of moments (MOM) analysis of electromagnetic phenomena, the LU decomposition is often an important and costly step in the solution process. In this reported work, the acceleration of LU decomposition using graphics processing units (GPUs) has been considered. Although existing GPU methods, such as those supplied by MAGMA, provide significant speedup over CPU-only implementations, they are limited to smaller problems by the amount of device memory available. The method now presented takes a left-looking LU decomposition as a starting point and uses an out-of-core like approach to significantly increase the size of the problems that can be solved. In addition, a hybrid implementation that utilises MAGMA as part of the solution process is presented, further improving the performance of the method. For the double precision complex variant of the LU decomposition, the number of MOM degrees of freedom that can be solved using a solver based on MAGMA and a GPU device with 1GB of memory is limited to 7936. Using the presented panel-based and hybrid approaches has already permitted problems more than four times larger to be solved with significant speedup.

FEA of electromagnetics: a geometrical approach for problems with plane symmetry

A geometrical approach for finite-element analysis of electromagnetic phenomena exhibiting plane symmetry is developed. The proposed method is developed for first-order triangular meshes. Electromagnetic fields inside any given triangular element are calculated as a linear combination of vectors associated with the sides of the element. The element stiffness matrix can be obtained from another matrix whose coefficients are the dot products of vectors associated with the sides of the triangle. This matrix is derived by applying the integral form of Maxwell's equations to contours suitably chosen in the finite-element mesh. The method is suitable for teaching finite-element analysis in electromagnetics at undergraduate level.

DIRECT DETERMINATION OF TWO‐PERIODIC SOLUTIONS FOR NONLINEAR DYNAMIC SYSTEMS

This paper presents a Newton‐Raphson algorithm for determining the Fourier spectrum of two‐periodic solutions for dynamic systems described by nonlinear ordinary differential equations. Assuming that two basic frequencies are known, the coefficients of a double Fourier series result from this algorithm. An application to the analysis of electromagnetic phenomena in electromechanical converters is described. In an example, of the steady‐state performances of current in a simple converter, the algorithm is tested with very good results.