P. Di Barba

Evolutionary Multiobjective Optimization Methods for the Shape Design of Industrial Electromagnetic Devices

The purpose of this paper is to focus on multiobjective optimization methods that are suitable for industrial electromagnetic design. In particular, a multiobjective optimization procedure is proposed, where the computation time is reduced by adjusting the refinement of the mesh, according to the accuracy required for the search in the design space rather than for the field analysis. A case study, dealing with the shape design of a small generator for automotive applications, is solved by comparing different procedures of optimization. Finally, a review of open problems is presented and discussed.

An improved technique for enhancing diversity in Pareto evolutionary optimization of electromagnetic devices

When a multiobjective optimization problem is tackled using Pareto optima theory, particular care has to be taken to obtain a full sampling of the Pareto Optimal Front. This leads to variability of individuals in both design space and objective space. We compare two different fitness assignment strategies based on two individual sharing procedures in the space domain and in the objective domain on some test cases.

Coupled field synthesis in Magnetic Fluid Hyperthermia

In this paper, the actual synthesis of the thermal field is proposed and solved as an inverse problem, considering a fully coupled magnetic-thermal analysis as for the direct problem. Reference is made to an air-cored inductor for magnetic fluid hyperthermia (MFH).

Optimization of the MIT Field Exciter by a Multiobjective Design

This paper deals with the shape design of the excitation unit of a magnetic induction tomography (MIT) system by means of a procedure of multiobjective design. As a result of the proposed method, a set of optimal geometries of the basic excitation structure was found.

Synthesizing Distributions of Magnetic Nanoparticles for Clinical Hyperthermia

An automated procedure based on evolutionary computation and Finite Element Analysis (FEA) is proposed to synthesize the optimal distribution of nanoparticles (NPs) in multi-site injection for a Magnetic Fluid Hyperthermia (MFH) therapy. In particular a bi-objective formulation of the synthesis problem is considered taking into account both surface and volume temperature distribution in the tumor region.

Industrial Design With Multiple Criteria: Shape Optimization of a Permanent-Magnet Generator

The purpose of the paper is to demonstrate that the multicriteria formulation of an inverse problem fits well with current industrial electromagnetic design. The optimal shape design of a permanent-magnet (PM) generator is developed as the case study. Two well-known evolutionary algorithms, NSGA-II and MOESTRA, have been implemented and relevant results compared.

Optimal shape design of devices and systems for induction‐heating: methodologies and applications

The paper reports recent experiences of the authors in the automated optimal design of devices and systems for induction heating. The results presented have been obtained in the frame of a long‐lasting cooperation between Laboratory of Electroheat, University of Padova and Electromagnetic Devices CAD Laboratory, University of Pavia. In particular, two case studies are discussed; in both cases, the shape design of the inductor is carried out in a systematic way, by minimizing user‐defined objective functions depending on design variables and subject to bounds and constraints. When the design problem is characterized by many objectives which are in mutual conflict, the non‐dominated set of solutions is identified.

A fast evolutionary method for identifying non‐inferior solutions in multicriteria shape optimization of a shielded reactor

When tackling the multicriteria optimization of an electromagnetic device, the accurate sampling of the Pareto optimal front implies the use of complex and time‐consuming algorithms. In several cases, however, the identification of a few non‐inferior solutions is often sufficient for the design purposes; as a consequence, the computational cost may be reduced. A simple evolutionary methodology is proposed to obtain a fast approximation of non‐inferior solutions; the optimal shape design of a shielded reactor is presented as a case study.

Biogeography-Inspired Multiobjective Optimization and MEMS Design

A new version of the biogeography-based optimization algorithm is proposed in order to consider multiple objectives. In fact, by exploiting non-dominated sorting of habitats, it is possible to approximate Pareto-optimal solutions in the objective space. The optimal shape design of an electrostatic micromotor, which is a benchmark in the Micro Electro-Mechanical Systems design, is considered as the case study.

3-D computer aided analysis of the "Berkeley" electrostatic micromotor

The basic ideas of IC-processed electrostatics are reviewed. The three-dimensional field model of a variable-capacitance electrostatic micromotor is then presented and the underlying analysis problem is solved by means of the finite element method. The micromotor, acting as a position actuator, is investigated at steady state and particular attention is paid in the calculation of the torque-angle curve featuring the device. The influence of stator geometry on the electromechanical performance is also investigated and design considerations are accordingly drawn. Finally, the step-transient response of the actuator is simulated. >