This paper discusses the method of analysis of specific power loss in the joint area of steel laminated core. The method is based on comparison of power loss data obtained from the tests of a circular shape magnetic core. Initially, the core build using uncut (solid) lamination sheets was tested to obtain the loss reference values. Then the laminations were cut onto four sections, and the core was tested again to obtain the loss increase associated with the implemented joint area. The test readings were processed to separate losses due to tangential and normal fluxes in the laminates. The processed data represented as relative p.u. values of increase in specific power loss have been extended to conduct an analysis of a rectangular magnetic core made using anisotropic, grain-oriented silicon electrical steel. The results demonstrated that the power loss produced by the normal magnetic flux dominates in the structure of total power loss in the rectangular core (approx. 85%). The proposed approach utilises the septation of losses produced by tangential and normal fluxes; it can be applied for the analysis of loss in the joint areas of magnetic cores of various power transformers.

The article is devoted to the device for automatic control of power flows in smart grids of medium voltage. A description of proposed method of vector regulation of power flows in a power transmission line using a solid-state voltage regulator (SSVR) is given. SSVR allows one to adjust the current in the line by introducing an additional EMF and changing the voltage drop across a network choke with known electrical parameters. A vector diagram of voltages and currents is given, explaining the principles of forming parameters of the current of the network choke. The Vector In and Vector Out virtual instruments for controlling the SSVR input and output voltage converters respectively are developed in the LabVIEW. Virtual instruments regulate the parameters of the vectors and implement the control of electrical potentials on the network choke. The test results of the developed control system confirmed the effectiveness of vector regulation.

The paper describes an experimental model of a hybrid power source (HPS) on the basis of solid oxide fuel cells (SOFC) being developed by the authors. HPS includes generating system, power storage system, pairing system and an active-adaptive control system. Generation system includes a reformer and a modular electrochemical generator based on SOFC. The storage system consists of a capacitive storage (CS) and accumulation batteries (AB). Accumulation batteries are made of alkaline nickel-cadmium batteries with improved power characteristics. A converter of current distribution (CCD) makes the basis of HPS pairing system. The authors developed a schematic diagram of CCD with three DC/DC upconverters. To implement an active-adaptive control system an algorithm of HPS operation was developed. The investigation of currents redistribution modes was carried out on the HPS simulation computer model developed by the authors. The research made it possible to determine the mode of stabilization of generated power, providing maximum SOFC utilization ratio.