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The main limit of an electromagnetic design lies in its thermal performance. Accurate prediction of the temperature within a new device is therefore very desirable. The purpose of this paper is to present an accurate method of predicting temperature that has been applied for design of a high‐energy density choke.

The thermal analysis has been carried out using initially a two‐dimensional (2D) finite element method (FEM) and then a thermal lumped parameter network. The heat flow within the network was informed from the 2D FEM analysis.

The presented lumped parameter thermal model of the high‐energy density choke has been experimentally validated and shows good agreement with the test data. The high‐energy density equal to 0.49 J/kg is demonstrated as a result of the improved thermal management and permanent magnet biasing.

The results show a 1.75 increase of the energy density for the new choke design as compared with more conventional design. The low weight and volume of such components are desirable in many applications including automotive and aerospace.

The presented method allows for fast temperature predictions that can be used in design and optimisation of high‐energy density inductors.

A brushless, permanent magnet, three‐phase disc‐type salient‐pole DC motor with co‐axial flux in the stator is considered. Electromechanical properties of a basic eight‐pole motor are compared with those for a 16‐pole one of the same volume, in order to contrast the two potential candidates for variable‐speed, low‐cost drives. As a basis of the comparative analysis, 3D FEM magnetic field modelling and circuit analysis considering an electronic commutator are employed. Increasing the number of poles results in unfavourable raising in the switching frequency. The eight‐pole motor construction has been shown in simulations to have higher efficiency and lower power losses than its 16‐pole counterpart.

This paper presents the field‐circuit analysis of a disc‐type torus DC motor with permanent magnets. Calculations of the magnetic field are carried out using the finite element method (FEM) in the 3D space. The integral quantities like the ripple‐cogging torque, back electromotive force, flux linkage, self and mutual inductances of the winding are analyzed. The electromagnetic torque is comparatively determined from the Maxwell stress tensor and co‐energy methods. Based on the 3D magnetic field calculations, the lumped‐parameter model of the tested motor is constructed, taking into account an electronic power converter as well. For comparison, various permanent magnet widths and teeth thicknesses of the stator core are considered. The torque pulsations are shown in simulations to be effectively reduced by an appropriate selection of a permanent magnet width on the pole pitch. Additionally, the efficiency of the tested motor can be significantly improved by a proper selection of the teeth thickness. The simulation results are verified with experimental data obtained from the slotless version of the motor prototype.

The purpose of this paper is to analyse the stray losses in the windings of permanent magnet synchronous machines (PMSM).

The 2D field model, based on the edge element method (EEM) and

-V formulation, has been developed and utilized for the determination and analysis of stray losses in the PMSM with concentrated windings made of strip conductors. The influence of the supply frequency as well as the slot opening width on the losses caused by eddy currents has been examined. The different arrangements of the conductors in the tape wound coils have been studied. The obtained results have been compared to the reference case when the eddy current effect is neglected.

The usefulness of the proposed methodology of the stray losses evaluation has been tested on the case study problem. It has been observed that the stray losses in the windings of the considered machine can be reduced by choosing the proper value of the slot opening. The dependence of the stray losses on the frequency of the supply currents has been examined. The obtained results show that with the increase of frequency the stray losses caused by the eddy currents in the strip conductors increase.

The proposed 2D field numerical model makes it possible to analyse the stray losses in the tape wound concentrated windings of the PMSM motor. The presented model can be utilized for the optimization of the magnetic circuit of the machine with the aim of minimizing eddy current losses.