Improved Version of Energy Efficient Motor for Shell Eco Marathon: Half Weight with Higher Efficiency

Abstract

The goal of the thesis is to analyze an existing Axial Flux Permanent Magnet motor used for Shell Eco Marathon from the Norwegian University of Science and Technology (NTNU). The existing machine has been analysed and modified to achieve improved power density at high efficiency with lowered weight.A detailed literature study on AFPM machine topologies, winding and magnet arrangements is covered. The magnet arrangement of the existing machine has been transformed from conventional North-South to Halbach array. The preliminary analytical calculations were done by using analytical expressions. After that, for an improved design, an efficiency-based optimization has been used to improve the obtained parameters from analytical calculation. This optimization has been performed with the help of fmincon solver in the Matlab optimization tool. The optimized values after being compared with the analytical calculation, has been used to run Finite Element Method simulations.The new design with optimum performance parameters displays an improvement of overall efficiency with decreased weight in comparison. The new machine has a 97.2% efficiency and weights only 6.24 kg. In comparison with the existing machine, the weight of the new machine is almost half with improved efficiency.KeywordsAxial Flux, Permanent Magnet, Synchronous Motor, Ironless Stator, Halbach.