OPTIMIZATION OF A WOUND ROTOR SYNCHRONOUS MOTOR FOR AUTOMOTIVE APPLICATION

Nowadays, the automotive industry is facing a deep evolution because of the inevitable replacement of Internal Combustion Engines by electric motors. This derives from the need to increase sustainability and reduce environmental damage. With the expected dominant production of Electric Vehicles in the future, the optimization of motor performance and efficiency must be an area of profound research and needs to face the rapid change of the entire industry. At the moment, the most promising adopted electric motor for traction purposes is the Interior Permanent Magnet Synchronous Motor (IPMSM), since this propulsion system offers very high power density and efficiency. However, at higher speeds this motor topology can not reach high torque levels, limiting its performance range. Another important tradeoff is the essential need to rely on rare-earth Permanent Magnets producers, implying dependence on them and resulting in high volatility and potential increases in costs. As an alternative to IPMSMs, Wound Rotor Synchronous Motors appear as a promising alternative for traction applications, in particular for ones requesting constant power across a broad speed range.  Considering the mentioned robust performance in the field-weakening region, WRSMs offer the possibility of varying the magnetizing flux and adopting more complex and efficient control strategies, without the need for rare-earth materials as the ones used for the production of Permanent Magnets. Therefore, the main objective of this thesis is to design and optimize a WRSM that can effectively replace the IPMSM in automotive applications. The starting point of this process is the IPMSM stator, which it is maintained throughout this work. The focus of the project is to identify the most efficient and power-dense wounded rotor configuration, involving detailed analytical and Finite Element Method (FEM) modeling, design, optimization and analysis techniques. At the end, the optimized WRSM is judged against its possible attainment of high-performance metrics, in comparison with the IPM synchronous motor.