S. Brisset

Optimization with experimental design: an approach using Taguchi's methodology and finite element simulations

In this paper, an optimization method, based on fractional experimental design, is proposed and applied to the design of a brushless DC motor. Taguchis methodology and a limited number of finite element simulations are used to build an approximation of the cost function of an optimization problem. This approximation allows one to quickly locate the global optimum.

Investigation on Multi-star Structures for Large Power Direct-drive Wind Generator

Abstract In order to increase the power capability of direct-drive PM wind generators with respect to established quality criteria like the electromagnetic torque and the power transferred to the grid, a polyphased multi-star system is studied. The influence of the number of stars, their phase shift and the waveform of the electromotive force are investigated. The possible configurations, i.e. the numbers of magnets and slots, are found and compared.

Analytical model for the optimal design of a brushless DC wheel motor

Purpose – Analytical models are often used in the first steps of the design process. They are associated with optimisation methods to find a solution that fulfil the design specifications. In this paper, the analytical model of an electric motor is built and proposed as a benchmark to highlight the optimisation methods the most fitted to analytical models.Design/methodology/approach – This paper studies the optimal design of a brushless DC wheel motor. First, the analytical model is presented. Each equation used for the sizing is described, including the physical phenomenon associated, the hypotheses done, and some precautions to take before computing. All equations are ordered to ease their resolution, due to a specific procedure which is then described. Secondly, three optimisation problems with an increasing number of parameters and constraints are proposed. Finally, the results found by the sequential quadratic method point out the special features of this benchmark.Findings – The constraint optimisat...

Polyphased modular direct-drive wind turbine generator

The goal of the paper is to study the possibility of increasing the power capability of direct-drive PM wind generators with respect to the established quality criteria: electromagnetic torque and the power transferred to the grid. The studied solution is a polyphased system with a phase number multiple by 3, i.e. a multi-star system. The influence of the number of stars and their phase shift are investigated

Optimization of switched reluctance motors using deterministic methods with static and dynamic finite element simulations

This paper presents the shape optimization of a switched reluctance motor (SRM) using a finite element model and several deterministic methods. Firstly, the experimental design method is used to determine the SRM shape that produces the higher static torque, then a shape sensitivity analysis is carried out beyond the feasible triangle limits. Secondly, deterministic methods are compared on SRM dynamic optimization with regard to motor performances and the number of finite element simulations needed. The optimized motor shape and transistor drive allow a high torque without a large current peak.

A new tabu search method for optimization with continuous parameters

A new tabu search algorithm for global optimization of multimodal functions with continuous variables is presented. The taboo list contains all points and a prohibited zone around each point that depends on the value of the objective function and decreases as the number of iteration increases. The numerical results obtained by solving problems 22 and 25 of the TEAM workshop demonstrate the speed effectiveness of the proposed method. It is compared favorably with other tabu search, genetic algorithm, and simulated annealing.

Adapted Output Space-Mapping Technique for a Bi-Objective Optimization

Multi-objective optimizations by means of 3-D finite element models result in very high computation burden. To have an affordable computation cost, the output space-mapping technique is applied with a new method where the scalar correction of the model outputs is replaced by a set of corrective functions. This method is used for the bi-objective optimization of a transformer and allows finding the complete Pareto optimal set in less than two days on a laptop.

A stop criterion to accelerate magnetic optimization process using genetic algorithms and finite element analysis

In this paper, a new stop criterion is proposed for genetic algorithms using a response surface fitted on the best individuals. This criterion is tested on a superconducting magnetic energy storage optimization and compared with stop criteria found in the literature that are reviewed and detailed.

A New Efficient Method for Global Discrete Multilevel Optimization Combining Branch-and-Bound and Space-Mapping

This paper presents a new method to handle discrete or mixed constrained optimization problems based on a high-fidelity 3-D finite element computational model. The original idea aims to combine branch-and-bound method that is enabling to ensure a global optimal solution and space-mapping techniques that allow to speed-up the optimization procedure by aligning a fine model and a coarse model. These algorithms are applied to design optimally a safety isolating transformer with categorical and integer design variables.

Optimal design of traction motor in railway propulsion system

Continuous decreasing in price of permanent magnet attracts many industries to invest in the development of permanent magnet synchronous motor, especially in traction application because of its high efficiency and compactness. In this paper a design of surface-mounted permanent magnet (SMPM) synchronous motor has been studied. The optimal design of SMPM motor can be achieved by applying a global design process and the multiobjective optimization.