Abstract
To find the temperature rise for high power density yokeless and segmented armature (YASA) axial flux permanent magnet synchronous (AFPMSM) machines quickly and accurately, a 3D lumped parameter thermal model is developed and validated experimentally and by finite element (FE) simulations on a 4 kW YASA machine. Additionally, to get insight in the thermal transient response of the machine, the model accounts for the thermal capacitance of different machine components. The model considers the stator, bearing, and windage losses, as well as eddy current losses in the magnets on the rotors. The new contribution of this work is that the thermal model takes cooling via air channels between the magnets on the rotor discs into account. The model is parametrized with respect to the permanent magnet (PM) angle ratio, the PM thickness ratio, the air gap length, and the rotor speed. The effect of the channels is incorporated via convection equations based on many computational fluid dynamics (CFD) computations. The model accuracy is validated at different values of parameters by FE simulations in both transient and steady state. The model takes less than 1 s to solve for the temperature distribution.
Highlights
yokeless and segmented armature (YASA) axial flux permanent magnet synchronous machines (AFPMSMs) have been providing challenging opportunities for industries for several years
This paper develops a fast parametrized 3D thermal model by coupling a separate lumped parameter thermal network (LPTN) of the stator and rotor through the introduction of the analytical convective heat transfer coefficients in [18,19]
It is worth mentioning that the model took around 1 s to be solved, which is a small time that allows for rapid calculation of the machine temperatures and use in further thermal studies on the YASA AFPMSM machine
Summary
YASA (yokeless and segmented armature) axial flux permanent magnet synchronous machines (AFPMSMs) have been providing challenging opportunities for industries for several years. The proper design of this machine requires the development of accurate and fast models of the YASA machine These include electromagnetic, mechanical, and thermal models for the machine. Authors in [8,9] developed mechanical analytical models for the YASA machine for a proper structural analysis of the rotor and stator for large-scale applications. To study the air flow and heat flow in the airgaps of the YASA machine in more detail, the authors in [19] included the PMs on the rotor surface and developed analytical equations for the heat flow on the boundary surfaces taking into account the air flow inside the channels between the PMs. the model is not yet a complete motor model, because the solid parts of rotor and stator are not modelled. The effect of air gap length, rotor speed, and geometrical parameters of the magnet on the machine temperature is investigated by the FEM and LPTN model
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
