Abstract

For many years the automotive industry has been focused on reducing emissions of combustions engines in line with stringent regulations. One of the major challenges is in the development of new electrified powertrain of which electrical machines is an integral component. With the emergence of electric vehicles and the significant reductions of permanent magnet material and its related cost, new challenges arise. In particular, the design of electric machines smaller in size and weight along with higher torque and power density, needs better innovative cooling concepts to not overheat. This implies a strong need of multi-physic analysis, namely electro-magnetic in combination with thermal and fluid dynamics. In this presentation, a novel approach using a finite volume discretization technique to a 2D section of an electric machine and obtain the magnetic field and loss distribution and exchange the data with the full 3D CFD thermal model in a single user environment. This approach is a truly multi-scale, multi-physics modelling of the loss and temperature distribution in an electric machine in operation to assess its performance. This approach to meet the design challenges considers the e-machine design in its full complexity, starting with: 1. A description of the machine design and the challenge to access to all machine locations when performing experimental measurements 2. Followed by a discussion on the various cooling strategies and how they can be essential to the machine performance improvement to meet the new market and performance targets 3. Design changes for new innovations is not straightforward and expensive to build prototype, this is where high-fidelity with fully coupled physics can add to the design process 4. The discussion is concluded by a presentation of various simulation results highlighting the benefits in accessing to all parts of the machines and in exploiting a high fidelity modelling approach to get the true behaviour of the machine. This will help understanding what improvements make the difference on a digital prototype adapted for fast design changes.