Ferrofluid‐based electrical machines: Conceptualization and experimental evaluation.

This article intends to propose a new concept of electric machines that works based on a category of magnetic fluids called "ferrofluids". For this purpose, a disc‐shaped rotor filled with ferrofluid material is employed instead of a common rotor of an axial‐flux machine, and the conceptual design of the new machine named here "axial‐flux ferrofluid electric machine (FFEM)" is presented. The operation principle of the FFEM is described and a dynamic‐transient model built on the d–q axes equivalent circuits is presented. Simulations are carried out by applying the given model in MATLAB and the results are investigated in different operating conditions. In order to identify the basic parameters and validate the simulation results, a prototype of the FFEM has been designed and manufactured, and some preliminary functional tests have been performed on the prototype. All simulation and experimental results indicate some distinguished excellent performances of the new machine. In the end, it can be stated briefly with some confidence that ferrofluid electric machines can have a high potential for future research and applications in various industries due to the simplicity of the structure, self‐starting capability, ability to work at a wide range of speeds and a flat torque profile. [ABSTRACT FROM AUTHOR]