size of the wheel of the vehicle, a high mean torque must he provided to satisfy the ..... complicated thermal model based on an equivalent circuit with thermal ...
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IEEE Transactions on Energy Conversion, Vol. 14, No. 4, December 1999
Application of a new optimization approach to the design of electrical wheels C.Espanet, J.M. Kauffmann (IEEE Member) Institut de GCnie Energetique 2 avenue Jean Moulin 90000 Belfort France
F. Wurtz, J. Bigeon Laboratoire d'Electrotechniquede Grenoble (INPGRIJF - CNRS , UMR 5529), BP 46, ENSIEG 38402 Saint Martin d'Heres Cedex France
Abstract - This paper deals with the optimization of the design of electrical wheels. A new approach is used that generates the optimization software. It allows.the design to he made with a more elaborate analytical model of the structure chosen for the wheel. Thus, it is possible to obtain a very efficient optimization program. This will he illustrated on the example of an electrical wheel for a hicycle. Keywords: Optimization methods, Brushless rotating machines. I. OUR GOAL: THE EFFICIENT DESIGN AND OPTIMIZATION OF ELECTRICAL WHEELS The design of a motor integrated in a wheel is a quite difficult problem. The designer has to model and take into account all the physical phenomena that are often non-linear and interdependent. He must also respect hard constraints: the maximum dimensions of the motor are bounded by the size of the wheel of the vehicle, a high mean torque must he provided to satisfy the starting requirements and the losses generated must be compatible with the desired efficiency and the allowed temperatures. Finally the design has to he optimized for a criterion that may be the weight or the price of the structure. When the shxcture of the motor is chosen, a classical design procedure is the following [1],[2]: 1) Develop an analytical model of the structure, 2) write a design program that uses this model linked with an optimization algorithm. The aim of this paper is to show that, using a new approach, the programming of the optimization software can he automated. This facilitates the application of a very complex analytical model of the structure. To illustrate this, we will describe the program we obtain for electrical wheels as well as its use and the resultant motor designs.
11. A NEW APPROACH FOR THE CONSTRAINED DESIGN AND OPTIMIZATION OF ELECTRICAL DEVICES In a problem of design with constraints, the output parameters Psj, j=l,m of the device are linked to input parameters Pei, i=l,n: Psj=fj(Pei) (1) where f j are mathematical functions. PE-093-EC-0-12-1998 A paper recommended and approved by the IEEE Electric Machinery Committee of the IEEE Power Engineering Society for publication in the IEEE Transactions on Energy Conversion. Manuscript submitted Februaly 25, 1998; made available for printing December 17, 1998.
The constrained optimization problem can be formulated in this way: find a set of the design parameters Pei such that an objective function (which is one of the Pei or the Psj) is minimized and such that: Pemini < Pei
