As the use of photovoltaics becomes more widespread, new technologies for more efficient energy generation, transmission, and distribution based on power electronics converters are being developed. The most common applications are grid-on, energy storage, hybrid, and high voltage gain applications. These applications impose several additional requirements in the design of power converters associated with the solar battery’s maximum power tracking and operation in a wide range of input currents and voltages. The practical realization of such solutions can be implemented on the basis of various topologies, which requires a preliminary application of criteria for assessing their effectiveness. The paper conducts a comparison of different topologies on power converters based on two parameters that describe their cost and power loss for various PV applications. For a straightforward study, these parameters are represented using the gain factor, which allows for an accurate comparison of the efficiency of various types of converters.

This study proposed an approach to dynamic wireless charging that uses a rotating receiver coil. Our simulation study focused on the verification of a novel way of increasing the coupling coefficient and power transfer stability by following the flux of the transmitting coils. To obtain the highest possible coupling by means of the FEM analysis, we studied the optimization of the trajectory of the angular velocity of the rotating receiver. The coupling coefficient trajectories that were obtained were simulated by means of the state space model with three transmitters. Our comprehensive analysis showed that the proposed approach of wireless power transmission enabled a 40% increase in the usage of track space.

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Особливості проектування і керування вентильно-індукторним двигуном з мінімізацією пульсації моменту Лук'янов f М. О., ORCID 0000-0001-8930-9992 Вербицький s Є. В., к.т.н. доц., ORCID 0000-0001-7275-5152 Факультет електроніки Національний технічний університет України "Київський політехнічний інститут імені Ігоря Сікорського" kpi.ua Київ, Україна Анотація-Вентильно-індукторний двигун (ВІД) завдяки своїм перевагам може використовуватися в транспортних засобах низької й середньої потужності. Проте, на даний момент, через значні пульсації обертового моменту, недостатню питому потужність й складність драйвера він не є популярним. В статті розглянуто структуру ВІД і запропоновано відношення між полюсами статора та ротора для забезпечення високої ефективності. Для мінімізації пульсацій обертового моменту запропоновано спеціальну високочастотну методику формування струму обмотки статора. Наведено загальний алгоритм проектування ВІД із запропонованою структурою. Рис. 1 Спрощені структури ВІД: а) типова структура ВІД; б) досліджувана структура ВІД

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In the paper the types of motors for vehicles and highlights the switched reluctance motor type as one that has a simple design, high reliability and low cost. The principle of operation of switched reluctance motors (SRM) and their modifications are given. However, the widespread use of SRM in vehicles is constrained by the low specific torque and its high ripple. To increase the specific torque, a paired winding of windings on adjacent rods of U-shaped stator poles is proposed. The principle of formation of rotational force is shown and the estimation of efficiency of use of the electric power for its formation is offered. The COMSOL Multiphysics software environment analyzes the advantages and disadvantages of using U-shaped poles with a trapezoidal and rectangular profile, and selected the latter because of the greater torque at the same dimensions. It is shown that the width of the pole rods with a rectangular profile to ensure maximum torque should be about a third of the width of the base of the pole. A typical form of current of the pole winding, which minimizes the pulsation of the moment, is analyzed. The expediency of designing a specialized electric drive for the proposed topology of SRM and synthesis for it of the control law, which provides the required value of the moment with minimal ripple, is substantiated. As usual, to ensure the constant moment generated by the pole in a certain sector it is necessary to form a current of near trapezoidal shape in the pole winding. As a result of the research, conclusions were made about the possibility of reducing the cost of SRM technology when using a modular structure based on U-shaped poles with paired winding at the stator poles, in which the windings are wound on the rod of two adjacent poles, which allows them to be placed compactly the use of additional space and, accordingly, provides a greater density of the poles. Modeling the process of forming the torque of the motor in the COMSOL Multiphysics software environment showed the advantages of using poles with a rectangular profile compared to trapezoidal poles and confirmed the feasibility of using poles with a rod width of about a third of the pole base width.

The article analyzes changes in the legislation on the rules of electricity generation from renewable sources and the introduction of penalties for imbalances, which encourages producers to improve the forecast of electricity generation and modernization of existing power plants by installing energy storage systems. Possible connection points and charge/discharge device (CDD) converter topologies for an energy storage system are analyzed and the converter that meets technical requirements of the system are selected. As a result, the connection from the direct current side has a number of advantages: simpler CDD structure and control principle, in comparison with alternating current; no galvanic separation between input and output. Converter analysis showed, that due to a high operating voltage, usage of resonant topologies is undesirable and the absence of galvanic separation makes bridge converter usage impractical. Therefore, to solve this problem, a bidirectional converter without galvanic separation with hard switching is proposed. To reduce the level of dynamic and static losses, it is advisable to use a modular topology converter with alternating phases. The operating modes of such a converter at a given error of the weather forecast are analyzed. To improve quality of the generated electricity, it is expedient to use a power stabilization mode. Due to the higher values of charge/discharge currents, as well as higher energy density compared to acid-lead, a lithium-ion battery was chosen. According to the selected operation mode, its minimum capacity was calculated. When using a minimum battery capacity, due to the difference between the maximum discharge and charge current of the battery, a mode of partial power stabilization is possible. This mode is used only when the forecast error is more than 52% in the charging mode. A charge/discharge device were designed for a 50 kW SMA Sunny Tripower CORE1 inverter and 20*315W LP156*156-M-60 solar panels connected in series. The control principle for such CDD is described. Control algorithm can be divided into four stages: obtaining the predicted solar radiation power in the forecast interval; predicted illumination power conversion into electric power;  predicted power calculation and the amount of energy that will be generated  and transferred by the solar station to the regulator in the forecast interval; power setpoint stabilization on the forecast interval based on the proportional-integral (PI) control law. To verify the obtained theoretical relations, converter parameters with a typical input data were calculated. Model of the converter was created in the MATLAB® Simulink® environment and its operability was checked.

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