This 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.

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Magnetorheological (MR) actuators are known semi-active devices. In the essence, the hardware incorporates a valve being a solenoid with a flow channel. Supplying the current to the solenoid's coil induces the magnetic field in the channel. As a results, the fluid transitions from a near-Newtonian one to a pseudo-solid. In the paper we show that significant improvements in the MR actuator dynamics can be achieved by exploring flux feedback control systems rather than current feedback ones. The flux-based approach would improve the system's response time and its bandwidth as well as minimize the contribution of the eddy currents. Thus, numerical simulations have been carried out to test the original hypothesis. The obtained data (from co-simulations) prove that the proposed approach delivers good results although further research is required on further optimizing the controller's gains and prior to building a real prototype.

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