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This research introduces the simulation of photovoltaic (PV) array to track the peak point (MPPT) using fuzzy logic control. Therefore, real time simulation is performed in MATLAB/Simulink based on a PV model, boost converter and fuzzy logic-based tracker. A comparative study is carried out against perturb and observe (P&O) controller. The fuzzy logic technique based tracker can successfully track the maximum power point very fast and has precise control when compared to the P&O algorithm. The overall we conclude that the MPPT using the fuzzy logic technique takes a fast response and can improve the performance of the PV system.

One of the important tasks for increasing the efficiency of photovoltaic (PV) system is the development and improvement of the maximum power point tracking algorithms (MPPT). These MPPT algorithms lead to the ability to catch efficiently the global maximum power point of the partially shaded PV array. One of these trackers is the particle swarm optimization (PSO) algorithm which is one of the Soft computing techniques. The conventional PSO based trackers have many advantages such as the simplicity of hardware implementation and independence from the installed system. The actual problem of the practical application of PSO is the determination of its parameters to ensure high effectiveness of extracting the global MPP. Analysis of scientific papers devoted to the PSO algorithm has shown that there is currently no methodology for the optimal parameters' selection of PSO algorithm based maximum power trackers for the PV system. This paper aims to create a convenient and reasonable method for choosing the optimal parameters of the PSO algorithm, taking into account the topology and parameters of the DC-DC converter and the configuration of solar panels. A new method for selecting the parameters of a buck converter connected to a battery has been presented. The optimal value of the sampling time for the digital MPP controllers, providing their maximum performance; has been determined based on a new methodology. Matlab/Simulink software package is used as the main research tool. The prominent outcomes identify that the modified PSO and its designed parameters best meet the requirements of the MPPT controller for the PV system.

A maximum power point tracking (MPPT) is a method to extract the optimal operating point of the photovoltaic power generation system. Under partial shading conditions (PSC), the power voltage characteristics exhibit more than one local peaks and one global peak. This paper presents a cuckoo search (CS) algorithm to catch the global maximum power point of PV under PSC. The main contributions of this work are to minimize the tracking time and increase the tracking efficiency of the PV modules. Furthermore, this work aims to study the behavior performance of two MPPT techniques which have been designed for extracting the GMPP under the PSC. The developed algorithms are implemented in MATLAB/Simulink platform, and their performances are evaluated. In addition, a step up (boost) DC–DC converter is designed and interfaced with resistive load in the proposed model. The prominent outcomes show that the CS has the best performance compared to the Perturb and observe (P&O) techniques. In addition, for all test cases, the tracking efficiency of the CS is higher than 99.97% within 150–180 ms.

This paper presents an improved particle swarm optimization (PSO) algorithm for determining the global maximum power point tracking (GMPP) of photovoltaic (PV) array under partially shaded conditions (PSC). Under PSC, the power–voltage characteristics have a more complex shape with several local peaks and one global peak. Most of the conventional techniques that are applied in the maximum power-tracking control unit of PV stations do not provide reliable tracking of the GMPP under PSC, which leads to decrease the reliability and the performance of the PV power plant. The performances of the proposed PSO algorithm and the conventional perturb and observe algorithms are evaluated using simulations in MATLAB/Simulink. Eight different partial shading patterns have been selected to prove the robustness of the proposed algorithm. A (step-up) DC–DC boost converter is interfaced with the proposed model. The results indicate that the modified PSO algorithm can very fast track the GMPP within 150–280 ms for different shading conditions furthermore the quality of the tracked power is very high as compared with the previous studies in the literature. Also, the average tracking efficiency of the proposed PSO algorithm is higher than 99.8%, which provides good prospects to apply this algorithm in the control search unit for the GMPP in PV stations.

A model developed at the University of Tomsk, Russia, for high latitudes (over 55° N) is proposed and applied to the analysis and observation of the solar resource in the state of Sonora in the northwest of Mexico. This model utilizes satellite data and geographical coordinates as inputs. The objective of this research work is to provide a low-cost and reliable alternative to field meteorological stations and also to obtain a wide illustration of the distribution of solar power in the state to visualize opportunities for sustainable energy production and reduce its carbon footprint. The model is compared against real-time data from meteorological stations and satellite data, using statistical methods to scrutinize its accuracy at local latitudes (26–32° N), where a satisfactory performance was observed. An annual geographical view of available solar radiation against maximum and minimum temperatures for all the state municipalities is provided to identify the photovoltaic electricity generation potential. The outcomes are proof that the model is economically viable and could be employed by local governments to plan solar harvesting strategies. The results are generated from an open source model that allows calculating the available solar radiation over specific land areas, and the application potential for future planning of solar energy projects is evident.

The urgent task of modern energy is to ensure reliable and efficient power supply to consumers, even those located in remote, far end places. A hybrid energy system with renewable energy sources is a promising way to ensure such a process. A characteristic feature of the modes of such systems, especially with high penetration levels of renewable energy sources, is the presence of ripples in the charge–discharge currents of the batteries used as energy storage devices. Batteries operation with such current fluctuations leads to rapid degradation of its characteristics as well as a reduction in its lifetime. Furthermore, it leads to a decrease in the reliability of the power supply system and an increase in the cost of generated electricity. A significant drawback of hybrid systems built according to well-known standard schemes is the inefficient use of the primary renewable energy, which is especially critical for energy systems located geographically in areas with severe climatic conditions. This article proposes a new construction method and an algorithm for controlling the modes of hybrid energy systems based on a dual-circuit energy storage device, which increases their reliability and energy efficiency. The prominent outcomes of operating modes of a hybrid power plant with a high penetration of renewable sources are presented, which proves that the proposed method of construction and the proposed control algorithm provide reliable and efficient control of the power balance of the hybrid power system in all possible operating conditions. In addition, the overall efficiency of the proposed renewable energy system is increased from 28% to 60% compared to standard hybrid power plants.

One of principal components of hybrid power stations with renewable energy resources is the energy storage which characteristics define power and cost efficiency of all power generating system. In the article the analysis of operating modes of hybrid power station with the high level of substitution of organic fuel is made, the necessity of use of energy storage is proved. The original architecture of creation and a way of management of operating modes of a hybrid power generating system based on use of the double-circuit storage of energy providing the optimum modes of a charge of rechargeable batteries is offered. In a such way their safety and the maximum operation life is ensured.

In this study, introduces a cuckoo search (CS) algorism for determining the global maximum power point (GMPP) of photovoltaic (PV). The traditional methods are failed to track the global maximum power point under partially shaded conditions (PSC), which decrease the reliability of the power system and increase the system losses. The research results of the CS algorithm and perturb and observe (P&O) algorithm are investigated for different cases of operations of PV panels under PSC. The proposed CS model can track the GMPP very accurate with high efficiency in less time under severe weather conditions as well as in PSC.

The partial shading condition (PSC) often occur in large photovoltaic (PV) generation system (PGS), it causes system losses and many problems in reliability of power system. The power voltage ( p-v) curve under the PSC have more peaks local and global peak and this makes the track of maximum power is very difficult and the conventional algorithms can't track the global maximum power point in this case. In this paper, the maximum power point tracking (MPPT) under PSC are evaluated using the particle swarm optimization (PSO). The proposed model tracks the global maximum power point (GMPP) very fast and in very short time and don't exceed 30 iterations under minimum solar irradiation cases.

In the course of the power sector development a great attention is paid to the sources of small (distributed) generation. Distributed energetics allows flexible control of the system itself and energy losses reduction during transmission to consumers. Herewith, the most promising direction in the framework of energy conservation is usage of renewable sources. Exposition of the possibility of renewable sources use in the distributed generation system is an actual problem. The selection conditions of a wind farm in the distributed generation system are considered in the article.

This paper presents optimal parameters selection of particle swarm optimization (PSO) algorithm for determining the global maximum power point tracking of photovoltaic array under partially shaded conditions. Under partial shading, the power-voltage characteristics have a more complex shape with several local peaks and one global peak. The two proposed controllers include dynamic Particle Swarm Optimization, and constant particle swarm optimization. The developed algorithms are implemented in MATLAB/Simulink platform, and their performances are evaluated. The results indicate that the dynamic particle swarm optimization algorithm can very fast track the GMPP within 128 ms for different shading conditions. In addition, the average tracking efficiency of the proposed algorithm is higher than 99.89%, which provides good prospects to apply this algorithm in the control search unit for the global maximum power point in stations.

This paper presents a cuckoo search (CS) algorithm for determining the global maximum power point (GMPP) tracking of photovoltaic (PV) under partial shading conditions (PSC). The conventional methods are fail to track the GMPP under PSC, which decrease the reliability of the power system and increase the system losses. The performance of the CS algorithm is compared with perturb and observe (P&O) algorithm for different cases of operations of PV panels under PSC. The CS algorithm used in this work to control directly the duty cycle of the DC-DC converter without proportional integral derivative (PID) controller. The proposed CS model can track the GMPP very accurate with high efficiency in less time under different conditions as well as in PSC.

In this work, we examine the pressure and biaxial tensile strain dependence of the intervalley electron–phonon matrix elements in the lowest conduction band of GaAs, GaP, Si and Ge within the density functional perturbation theory. We study both individual transitions and average deformation potential values which can be used as parameters in transport simulations. In the case of a hydrostatic pressure, we draw the general conclusion that the hydrostatic pressure dependence of the intervalley electron–phonon matrix elements can be safely neglected in the interpretation of most commonly studied phenomena. In contrast, the case of a biaxial strain in silicon shows that strain-dependence should be taken into account in calculations of the intervalley electron–phonon matrix elements.

A diesel generator set working at variable speed to save fuel is studied. The results of experimental studies of the operating modes of an autonomous diesel generator set are presented. Areas for regulating operating modes are determined. It is demonstrated that the transfer of the diesel generator set to variable speed of the diesel engine makes it possible to improve the energy efficiency of the autonomous generator source, as well as the environmental and ergonomic performance of the equipment as compared with general industrial analogues.

The paper presents the results of simulation and study of operating modes of a photovoltaic power plant with the maximum power point tracking controller. A number of search methods are considered: constant voltage method, open voltage method, short circuit method, method of observing perturbations and incremental conductance method. A complex model of the photovoltaic power plant with the controller has been developed. The simulation results are presented. The model validity was evaluated by the known technical characteristics of the Solarex MSX 60 module. The calculation results proved that the obtained volt-ampere and volt-watt characteristics of the model are compatible with those of the manufacturer. The review of various methods of searching the maximum power point for the solar battery and analysis of their performance under different climatic conditions can be of interest for a broad range of experts in the field of photovoltaics.

A technique for simulation of domestic, social and industrial electrical loads in decentralized power supply systems is considered in the paper. To commercialize renewable energy plants as parts of self-contained systems, several engineering problems are to be solved; the most important of them is matching the power generation and operation conditions at stochastic time variations in the power demand and output power of a primary source. Energy consumption is a complex and time-dependent process and could be represented by several regular and irregular components. An approach to solution of the problem of matching the power generation and use conditions is mathematically described, which allows estimation of production volume and schedule of a self-contained power supply system based on the diesel-engine power plants or renewable energy sources. The solution suggested is tested for Yakutia and the Tomsk region as examples.

Solar photovoltaic technology is one of the most rapidly growing renewable sources of electricity that has practical application in various fields of human activity due to its high availability, huge potential and environmental compatibility. The original simulation model of the photovoltaic power plant has been developed to simulate and investigate the plant operating modes under actual operating conditions. The proposed model considers the impact of the external climatic factors on the solar panel energy characteristics that improves accuracy in the power output prediction. The data obtained through the photovoltaic power plant operation simulation enable a well-reasoned choice of the required capacity for storage devices and determination of the rational algorithms to control the energy complex.

The article reviews the current energy balance of Egypt's resources and sources of consumption, the main factors affecting the structure of the energy balance, the predicted trends of their changes in the short term, the main tasks of the electric power industry of Egypt and the ways of their solution. Based on the analysis of energy potential of renewable energy sources, the proposed types and locations of installations of renewable energy those have the greatest prospects for practical application.

The fast-growing photovoltaic system market leads to the necessity of the informed choice of major energy components and optimization of operating conditions in order to improve energy efficiency. Development of mathematical models of the main components of photovoltaic systems to ensure their comprehensive study is an urgent problem of improving and practical using of the technology of electrical energy production. The paper presents a mathematical model of the solar module implemented in the popular software MATLAB/Simulink. Equivalent circuit of the solar cell with a diode parallel without derived resistance is used for modelling. The serie8s resistance of the solar module is calculated by Newton's iterative method using the data of its technical specifications. It ensures high precision of simulation. Model validity was evaluated by the well-known technical characteristics of the module Solarex MSX 60. The calculation results of the experiment showed that the obtained current-voltage and current-watt characteristics of the model are compatible with those of the manufacturer.

The intervalley scattering time in n-type germanium from thevalley to the L, � ,a ndX valleys, has been computed ab initio with a method based on the density functional perturbation theory. We demonstrate that the pressure dependence of the lifetime of the exciton limited by the electron-phonon interaction is well described. Moreover, we discuss relaxation times measured by various pump-probe experiments at low and ambient temperatures. The contributions of the various phonons to the scattering are computed. Relaxation times due to the electron-phonon coupling are provided for each intervalley transition, as well as their behavior under pressure.

We have combined the Boltzmann transport equation with an {\it ab initio} approach to compute the thermoelectric coefficients of semiconductors. Electron-phonon, ionized impurity, and electron-plasmon scattering rates have been taken into account. The electronic band structure and average intervalley deformation potentials for the electron-phonon coupling are obtained from the density functional theory. The linearized Boltzmann equation has then been solved numerically beyond the relaxation time approximation. Our approach has been applied to crystalline silicon. We present results for the mobility, Seebeck coefficient, and electronic contribution to the thermal conductivity, as a function of the carrier concentration and temperature. The calculated coefficients are in good quantitative agreement with experimental results., 4 figures, 15 pages