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This work presents an optimization on the input impedance of Koch triangular quasi-fractal antennas using an efficient genetic algorithm (GA). The impedance matching is done by using an inset-fed, which is optimized to minimize the return loss (RL). The excitation of this structure is done using a microstrip line. The antennas are designed using the Ansoft Design™ software and the new structures,...
In this paper, a Multiobjective Quantum-inspired Particle Swarm Optimization (MOQPSO) approach based on Gaussian distribution probability operator is proposed. Numerical results are reported to validate the proposed MOQPSO to solve the TEAM (Testing Electromagnetic Analysis Method) workshop benchmark problem 25. MOQPSO was capable of finding nondominated solutions that represent the good trade-offs...
This paper presents optimization of meander line antennas for passive IC tags which contain non-linear circuits. In the present analysis, the tag antenna loaded by the Cockcroft-Walton circuit is analyzed by solving a coupling problem between electromagnetic waves and non-linear circuit with FDTD method. The antenna shape is optimized so that the output voltage of the Cockcroft-Walton circuit is maximized...
Optimization metaheuristics, such as particle swarm optimization, ant colony and bacterial foraging strategies have become very popular for electromagnetic device design. The Artificial Bee Colony algorithm is another example of bio-inspired swarm intelligence approach which is competitive with other population-based algorithms and has the advantage of using fewer control parameters. In this work,...
In this paper the optimization of a transverse flux induction heating by means of a particle swarm optimizer is presented. The novelty of this work is represented by the fact that concentric multi-coil induction heaters have never been optimized before in their full three-dimensional complexity.
This paper presents a methodology and a tool for the coupled magnetic-structural with semi-analytical models. For this coupling, the magnetic model is available, we developed the structural-contact model for the cantilever beam and valid it by finite element simulation. This coupling is dedicated to the optimization process of MEMS/NEMS in general and to nano switch in particular.
Sizing by optimization usually implies a model definition able to link the desired objective and constrained functions with the design parameters. When gradient based optimization algorithms are used, highly accurate derivatives are required. Without special software solutions, this procedure easily becomes time-consuming or error-prone. In this paper, our goal is to first observe the modeling needs...
Automatic Differentiation (AD) is introduced as a powerful technique to compute derivatives of functions given in the form of computer programs in high level programming languages such FORTRAN, C or C++. The paper applies AD to compute error-free gradients of sizing models describing electromagnetic devices. Then, the obtained gradients are exploited by optimization algorithms. The goal is to find...
An efficient mesh reconstruction method is proposed for remeshing the parameterized computation domain when using finite element method to optimize the shapes of electromagnetic devices. The proposed method has the merits of conserving the original structure of the mesh with minimal mesh deformation. The proposed method has been applied to TEAM workshop problem No. 25 and a permanent magnetic (PM)...
The performance of mobile phones has seen much improvement in recent years. It has thus become essential to produce higher quality microspeakers, which are a significant component of mobile phones. The major criteria used to evaluate microspeaker performance are the Sound Pressure Level (SPL) and the Total Harmonic Distortion (THD). Accordingly, it is essential to predict SPL and THD to ensure high...
In this paper, the efficiency optimization of an axial flux permanent-magnet synchronous generator with concentrated pole windings is examined for a 3.6 kW/2000 rpm combined heat and power application. A study of the influence of a limited set of geometry parameters on the efficiency of this type of machine is done, using both analytical and finite element methods. Finally, the results of both methods...
In this paper, we present a multiobjective evolutionary approach to design a microwave heating applicator. The goal for the device is to heat the maximum amount of water spending minimum energy. A set of optimal solutions is obtained, the Pareto front. A decision-making strategy was applied for selecting the point that corresponds to the most efficient device. The efficiency is improved by using a...
In this paper, the simulation and optimization electric field distribution in 550kV disconnectors of Gas Insulated Switchgear (GIS) are investigated employing the Finite Element Method (FEM) and Response Surface Method (RSM). The simulation results reveal that a uniform electric field distribution is achieved in 550kV disconnectors of GIS. This optimal prototype of disconnectors has been undertaken...
This paper presents an improved method based on Current Hoop Model for the analysis and design of capacitor-driven induction coilgun. For the optimal design, the sequential Genetic Algorithm (GA) method and traditional GA are used. The resultant specifications and characteristics of a six-stage coilgun are obtained by these methods. The comparisons of two optimization methods on the results, characteristics...
The torque ripple of a PM synchronous motor (PMSM) originates from two sources; the cogging torque and mismatch between the back EMF and phase current waveforms. The first source is only related to the magnetic design parameters of PMSM and the second source is related to the effect of the driving circuit on the magnetic design parameters. Therefore, achieving a minimum torque ripple requires a hybrid...
This paper presents an optimization method of the back EMF for the double layered(double air gap) large scale BLDC motor by using a Latin-hypercube sampling strategy. A new configuration of the double layered BLDC motor is also proposed for the compactness and high efficiency of the system.
To enhance the performance of a Thomson-coil actuator, generalized topology modification method is developed, and applied to the shape optimization of the conducting plate. In the method, shape optimization problem is treated as that of optimal assigning of material to each segment among available materials.
This paper introduces a multi-level robust surrogate-based optimization (MRSBO) applied to design of electrical machines. Manufacturing tolerances, material properties, operational and environmental conditions may generate uncertainties that can significantly affect machine performance. The framework developed includes the finite element method (FEM), statistical uncertainty quantification (SUQ) and...
An effective methodology for a robust global optimization of electromagnetic devices is presented. In the method, gradient index is minimized while the original objective function to be minimized is transformed to a constraint. Since the objective function values and gradient indices are approximated using surrogate functions, the method is numerically efficient.
Topological sensitivity (TS) formulation is derived, for the first time in RF domain, and applied to the hybrid-ON/OFF method for the fast solution of inverse problems. The formulation is based on continuum approach and adjoint variable method. The TS is directly calculated from volume field solutions, and used to determine the ON/OFF status of the unit cell. The proposed method is applied to dielectric...
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