Browsing by Author "Miotto, Ednei"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Analytical and numerical thermal modelling of a low power transformerPublication . Mendes, Gabriel Dias; Ferreira, Ângela P.; Miotto, EdneiIn past decades, thermal modelling of electric machines was overlooked and based on empirical experience. Due to modern requirements, using novel materials and innovative configurations, the thermal model became a crucial component in the modern design process. The thermal modelling can be performed by analytical methods, as the thermal resistance network (TRN) or by numeric methods as the finite element analysis (FEA). This work presents a methodological approach to thermal modelling, addressing both approaches and applying them to a study case of a low power shell-type single-phase transformer. The results from both approaches are compared with experimental results, achieving relative errors of 5.70% and 21.24% on the determination of windings' temperature, for the FEA and TRN model respectively, which helps define model improvements.
- Coupled electromagnetic and thermal analysis of electric machinesPublication . Mendes, Gabriel Dias; Ferreira, Ângela P.; Miotto, EdneiThis paper deals with the design process of electric machines, proposing a design flowchart which couples the electromagnetic and thermal models of the machine, assisted by finite element techniques. The optimization of an electrical machine, in terms of the energy efficiency and cost reduction requirements, benefits from the coupling design of the electromagnetic and thermal models. It allows the maximization of the current density and, consequently, the torque/power density within thermal limits of the active materials. The proposed coupled electromagneticthermal analysis is demonstrated using a single-phase transformer of 1 kVA. Finite element analysis is carried out via ANSYS Workbench, using Maxwell 3D for the electromagnetic design, with resistive and iron losses directly coupled to a steady-state thermal simulation, in order to determine the temperature rise which, in turn, returns to electromagnetic model for material properties update.