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This paper describes a new concept in construction of cable terminations for medium voltages. Layers with a high permittivity and embedded electrodes (EEs) were used. Three groups of configurations were examined. In the first group, the layer of high permittivity was placed partly over the cable insulation and partly over the cable screen. In the second group, the high permittivity layer (HPL) was placed partly over the cable insulation and partly under the semiconducting material, connecting with cable insulation screen. In the third group the cable screen was partly inserted into the H P L whose other part was placed over the cable insulation. The EEs were made in a shape of rings around the HPL. The rings were made either of copper tape or copper wire. Different positions of the EEs were examined. Numerical models of the cable L

Insertion of embedded electrodes (EEs) inside a MV XLPE cable termination strongly affects electric field around the termination and accordingly must be carefully considered. In this paper, influence of embedded electrodes on voltage distribution in some constructions of the 20 kV cable terminations was analyzed. Different options were considered for a specific number of the EEs along the cable insulation surface, taking into account possible effects of floating or grounded EEs, their different position and separation. In every option, a basic method of stress relieving with resistive layer over the end of semi conducting screen and primary cable insulation was applied. Reference design was a cable termination without EE. Its voltage distribution, total electric field and tangential component were observed for comparison. The stress relief materials, in the shape of pads or tubes, were used. Their properties were kept the same in all constructions. Voltage distribution was monitored, starting from the end of the primary cable insulation in the vicinity of the phase conductor and ending at the cable insulation attached to the semiconducting screen end at ground potential. The different design options were experimentally verified.

Abstract-A simplified model of a brushless DC motor segment is studied in this work. Shielding of the ferromagnetic structure with a high conductivity layer is explored. The shield is supposed to reduce the ohmic losses of the magnets and of the entire structure, particularly at the higher frequencies. In order to verify that, both calculations and measurements of the power loss are accomplished for the model first. In conclusion, locked rotor measurements are performed on a real BLDC motor in order to validate the results.

In this paper magnetic field of electrical radiant heating system (ERHS) is considered. Typically, cable system of ERHS is planar, and it can be built into the floor, wall or ceiling. The magnetic field generated by ERHS depends on the intensity of the current, which in turn depends on the size of the heating area. According to our results, single wire ERHS can generate magnetic field considerably higher than the background field. Key words: Electrical radiant heating system, magnetic field, magnetic field exposure.