Method for selecting parameters and assessing efficiency of wind-diesel power plants for autonomous electrical supply systems

The article presents an original technique for selecting parameters and evaluating the efficiency of wind-diesel power plants for isolated power supply systems. The initial data to perform energy calculations are simulation models of electric load and wind speed. The load is simulated using typical schedules of electric loads of a decentralized consumer, taking into account a random component for each hour of the day. To create a simulation model of the wind, a typical climatic series of wind speeds at a prospective site of the power plant has been constructed according to the data of long-term meteorological observations. The proposed technique was verified through the example of choosing a wind-diesel power plant for the village of Ust-Olenyok of the Republic of Sakha (Yakutia)

Investigation of parameters variation of speed controller on the frequency responses in vector automatic control system

The article considers the method of adjusting the frequency converter on preset quality parameters of transients. Regulation is carried out by means of changing the parameters of proportional-integral speed controller at constant performance of closed-loop current controller. Influence of parameters the proportional-integral speed controller on frequency response of vector control system is shown. Results of the simulation and experimental investigations based on the frequency converter Siemens Sinamics S120 are given. Recommendations for adjust settings of closed-loop speed controller of the vector control system at different performance are proposed as a conclusion.В статье рассматривается методика настройки преобразователя частоты на заданные показатели качества переходного процесса. Регулирование происходит за счет изменения параметров пропорционально интегрального регулятора скорости при неизменном быстродействии контура тока. Показано влияние параметров ПИ регулятора скорости на частотные характеристики векторной системы управления и показатели качества переходных процессов. Приводятся результаты моделирования и экспериментальных исследований на базе преобразователя частоты Siemens Sinamics S120. В качестве вывода предложены рекомендации для настройки контура скорости векторных систем управления с различным быстродействием

Ansys multiphysics simulation applying for work blade near steam extraction

В статье ставится задача применения междисциплинарного анализа при расчете околоотборных ступеней паровых турбин. На основе опубликованных работ описываются проблемы, которые необходимо решать при расчете и проектировании лопаточного аппарата. Описывается необходимость разработки унифицированной методики прочностного расчета рабочих лопаток околоотборных ступеней.The purpose of this work is ansys multiphysics simulation applying for work blade near steam extraction. The problems that must be addressed in calculation and design of blading describes on the basis of published works. The development applicability of standardized methods of work blade strength calculation is describe

Modelling fluid dynamics of turbine stages located near steam extraction

The purpose of this work is computational fluid dynamics of turbine stages № 19, 20 located near steam extraction. Design of stages model is described. The main steps of calculations and expected results are presents.Ставится задача проведения газодинамического анализа околоотборного отсека 19-20 ступеней турбины типа Т-100 производства АО «УТЗ». Описывается рассчитываемая модель околоотборного отсека с указанием зон, в которых возможно нарушение равномерного потока. Определяются основные этапы расчеты и ожидаемые результаты

Anomalous Behavior near T_c and Synchronization of Andreev Reflection in Two-Dimensional Arrays of SNS Junctions

We have investigated low-temperature transport properties of two-dimensional arrays of superconductor--normal-metal--superconductor (SNS) junctions. It has been found that in two-dimensional arrays of SNS junctions (i) a change in the energy spectrum within an interval of the order of the Thouless energy is observed even when the thermal broadening far exceeds the Thouless energy for a single SNS junction; (ii) the manifestation of the subharmonic energy gap structure (SGS) with high harmonic numbers is possible even if the energy relaxation length is smaller than that required for the realization of a multiple Andreev reflection in a single SNS junction. These results point to the synchronization of a great number of SNS junctions. A mechanism of the SGS origin in two-dimensional arrays of SNS junctions, involving the processes of conventional and crossed Andreev reflection, is proposed.Comment: 5 pages, 5 figure

Formation of triplet molecular states in molecular photonics and radiation chemistry

The mechanism of formation of triplet excited states of molecular systems in photonics and radiation chemistry has been considered. Intersystem crossing processes, two-photon excitation of high triplet states, and their evolution are discussed. The specific features of the formation of triplet states in radiation chemistry have been considered. Examples of using the concepts of triplet states in various fields, such as molecular luminescence, photochemistry, radiation chemistry, photodynamic therapy, design of organic light-emitting diodes, and information recording, are presented

Stationary Flows of the Parabolic Potential Barrier in Two Dimensions

In the two-dimensional isotropic parabolic potential barrier $V(x, y)=V_0 -m\gamma^2 (x^2+y^2)/2$, though it is a model of an unstable system in quantum mechanics, we can obtain the stationary states corresponding to the real energy eigenvalue $V_0$. Further, they are infinitely degenerate. For the first few eigenstates, we will find the stationary flows round a right angle that are expressed by the complex velocity potentials $W=\pm\gamma z^2/2$.Comment: 12 pages, AmS-LaTeX, 4 figure