Design and Optimization of a Permanent Magnet Synchronous Generator with Flex PCB windings for vertical axis micro wind turbines

Flexible PCB windings are used in Permanent Magnet Synchronous Motors (PMSM) for the positive impact they have on the torque density compared to classical wired stators. This master’s thesis explores the interest of the technology in a generator topology. More precisely, axial-flux machines with one and two windings are analysed and optimized for the particular application of a generator for vertical axis micro wind turbines. A bi-objective approach is followed to optimize the efficiency and the costs of the machines. Single-Stator Double-Rotor topologies are found to have the best performances in the sense of the combined objectives. A thermal model is then developed to evaluate the temperature increase of open and closed machines in nominal and stress conditions. Open-shell axial machines have very good thermal capabilities and can go to very high power without overheating thanks to the passively pumped air-flux in the airgap. Finally, a prototype with one winding was constructed and tested to validate the results.