Analytical Calculation of Eddy Current related Losses and Parasitic Torque in PCB Windings

This paper presents an analytical calculation method for eddy current losses in flat conductors exposed to a magnetic air gap field. Such arrangements are typically found in slotless machines with printed circuit board windings. The generated eddy currents cause a parasitic braking torque, which is calculated based on the Fourier series representation of the magnetic air gap field and the conductor geometry. Therefore, this method allows a fast and time-saving numerical calculation compared to time-consuming finite element simulations. It also allows the prediction of the braking torque ripple curve caused by eddy currents in the conductor. Subsequently, this calculation method is verified by comparing the calculation results with experimental measurements and finite element analysis.