The student Yerai Moreno Lafuente obtained an EXCELLENT CUM LAUDE grade with mention International Doctorate
The student Yerai Moreno Lafuente obtained an EXCELLENT CUM LAUDE grade with mention International Doctorate
The student Yerai Moreno Lafuente obtained an EXCELLENT CUM LAUDE grade with mention International Doctorate
- Thesis title: High frequency analysis of permanent magnet motors
Court:
- Presidency: Claudia Steluta Martis (Technical University of Cluj-Napoca)
- Vocal: Konstantin Vostrov (LUT University)
- Vocal: José Enrique Ruiz Sarrio (Universitat Politècnica de València)
- Vocal: Aitor Etxeberria Urkia (ORONA EIC)
- Secretary:Javier Poza Lobo (Mondragon Unibertsitatea)
Abstract:
The trend towards electrification has led to an increased use of wide-bandgap semiconductors in electric drives. These semiconductors allow the development of high power density and high efficiency drives, but also present challenges related to Electromagnetic Interference (EMI) due to their higher voltage derivatives. These derivatives lead to voltage overshoots at the machine terminals, which can potentially damage the insulation of the machine. Therefore, the aim of this PhD is to develop a complete design methodology that makes it possible to optimise the electrical machine also from the Electromagnetic Compatibility (EMC) point of view.
The research begins with a comprehensive literature review on high-frequency modelling of electrical machines and the impact of design parameters on their high-frequency behaviour. This review also covers an overview of the current tools used for these models.
A novel high-frequency model of the electrical machine based on FEM simulations is presented. This model, validated on various industrial machines, extends beyond most existing models in the literature, covering a frequency range of 100 Hz to 50 MHz. The validation process incorporates data from 28 samples from one machine to account for manufacturing tolerances.
In addition, the high-frequency machine model is integrated in a whole drive model. This model, validated with experimental measurements, enables EMI analysis considering all drive components, including the inverter, cable and EMC filter. Unlike models in the existing literature that use motor behavioural models derived from experimental measurements, the proposed model uses impedance data from FEM simulations. This approach allows for the prediction of common-mode currents right from the design stage.
The thesis concludes with an analysis of how design variables influence the impedance of the electrical machine and, consequently, the drive´s common-mode currents. It introduces a new design methodology for electrical machines that incorporates the EMC perspective. Two industrial machines exceeding the EMI regulation limits serve as case studies. The thesis proposes a design improvement that successfully reduces their common-mode current. This last point highlights the significant contribution of this research to the field of electrical machine design and EMC optimisation.