| Summary: | In recent years, additive manufacturing has been gaining ground among traditional
manufacturing methods in many different applications. This is mainly due to its ease of
prototyping, material savings and above all the highly complex geometries that can be
achieved. Despite its many advantages, the use of additive manufacturing in electrical
machines has been limited. The lack of maturity of the manufacturing processes and the
increase in losses when applying additive approaches to some parts, mainly stators, have led
little implementation in the field of electrical machines.
The geometric freedom offered by additive manufacturing paves the way for the use of novel
optimisation techniques, such as topology optimisation. Traditionally, topology optimisation
has not been widely used because the complex geometries obtained by these algorithms are
not easily produced by traditional manufacturing methods. However, thanks to additive
manufacturing, topology optimisation has started to be used, mainly for mechanical
applications and it has demonstrated its ability to reduce weight without compromising
mechanical stability in several cases. Nevertheless, topology optimisation for physics other
than mechanical has not been thoroughly studied, let alone for the simultaneous optimisation
of different physics.
In view of the scenario described, this thesis investigates the benefits that additive
manufacturing and topology optimisation can bring to the design of electrical machines.
For the additive manufacturing of electrical machines, a thorough literature review is carried
out on the application of this manufacturing approach to different parts of electrical machines,
active and non-active. Two main case studies are presented: in the first, the rotor, the shaft,
the stator and the housing of an aerospace actuator are manufactured by L-PBF in FeCoV and
the assembled actuator is tested. In the second case, a rotor is manufactured in FeSi by LP-
DED. Finally, not considered an additive manufacturing case study itself in this thesis, but two
electrical conductor prototypes are manufactured in CuCr1Zr and an additional geometry is
manufactured in AlSi10Mg by L-PBF.
With regard to topology optimisation of electrical machines, a description of the main
topology optimisation methods used is given and their application to electrical machine
components is presented. In a similar way to additive manufacturing, two case studies are
analysed. First, a novel multiphysics - mechanical and electromagnetic - topology optimisation
method is presented, in which the rotor and the stator of a permanent magnet motor are
optimised simultaneously. This method is compared with two methods found in the literature,
SIMP and on-off. Secondly, another topology optimisation method is described and applied to
an electrical conductor model. The proposed algorithm involves a multiphysics - thermal and
electromagnetic - hybrid parametric topology optimisation approach. Two reduced length
geometries and one full length prototype are built via additive manufacturing.
Finally, conclusions regarding additive manufacturing and topology optimisation of electrical
machines are drawn from the work presented in this thesis. Future lines of work for additive
manufacturing and topology optimisation of electrical machines are also presented.
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