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Copyright of Revista Entramado is the property of Universidad Libre Seccional Cali and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the "Plan for the Development and Efficient Use of Energy until 2030" in Cuba, the use of autonomous photovoltaic systems (APVS) for the supply of electric energy is included. In the present work, an analysis of the topologies of the electronic power converters that make up the 300 W APVS is carried out. Both the charge regulator with maximum power point tracking and the inverter stage are studied from simulation and measurements at points of interest of the installation. The results obtained experimentally allow us to affirm that the charge regulator is composed in all cases by a synchronous step-down converter that manages the control of the maximum power point in the battery charging process. A push-pull DC-DC converter, together with a single-phase full-bridge converter with sinusoidal modulation, is in charge of supplying the alternating current at the output. [ABSTRACT FROM AUTHOR]

The use of renewable energy sources has increased exponentially worldwide. Cuba has implemented a program until 2030 where renewable sources play a fundamental role within the national energy matrix. The policy regarding the installation of solar plants has been to connect small plants of up to 5 MW, mainly in distribution networks. In this work an optimization algorithm is developed to identify the best connection points of small solar plants in distribution networks. The algorithm solves the problem through a power flow combined with a full N-P allocation model. The goal of the algorithm is obtaining the best points to connect solar plants in buses of a radial distribution network at to minimize total active power losses or the deviation of voltage profile. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The research belongs to a project approved by the National Energy Program. The objective of the work is to evaluate the protection effect that windbreak curtains can provide to a photovoltaic field located in a rural area, in the face of hurricane force winds, applying Computational Fluid Dynamics (CFD) tools. A windbreaker of Bugambilia (Bougainvillea spectabilis) of 2 and 3 m in height and porosities of 0.56 and 0.79 is simulated. The distribution of wind speeds in the environment of a photovoltaic field sector composed of ten batteries, made up of 10 photovoltaic modules each with an arrangement of 5x2 panels, are determined for different intensities and direction of the winds. Likewise, the aerodynamic loads and the Von Mises stresses acting on the panels are determined. As a result, it is obtained that the curtain provides effective protection to the entire photovoltaic field, preserving the integrity of the solar panels, due to the fact that the maximum dynamic tensions reached do not exceed the permissible loads for winds of up to 56 m / s (200 km / h) coinciding with the upper limits of the wind speed in category III hurricanes of the Saffir Simpson scale. [ABSTRACT FROM AUTHOR]

Currently, multiple studies are trying to establish alternatives that will allow for the reduction of the consequences of energy consumption and greenhouse gases. In this sense, photovoltaic solar energy has become a feasible option to alleviate this problem, also, new technologies have been sought to reduce the energy consumption of cooling devices, because they consume too much energy and use harmful refrigerants to accomplish their task. For this reason, Peltier cells can be a viable option to lower the temperature in closed spaces without generating waste or harmful emissions. In the present work, we propose to combine these initiatives in a unified system to take advantage of both technologies, implementing a cooling system that uses the thermoelectric effect to reduce the temperature inside, which is fed by an autonomous photovoltaic system using maximum power point tracking algorithms to improve its performance. The results show that the device is capable of lowering the temperature inside, allowing the conservation of elements at low and constant temperatures, without the disadvantages of common refrigerators. Finally, it is concluded that this system is a plausible possibility to replace cooling technologies where access to electrical energy is limited. [ABSTRACT FROM AUTHOR]

A mathematical model is proposed for stochastic estimation of the number of the SARS-COv-2 virus infected person in places where there is a high concentration of population, such as shopping centers or other closed spaces. The aim is to obtain a mathematical model of virus propagation in closed spaces calculating the number of infected depending on compliance or violation of safe distances and compliance with protection standards, as well as a heuristic algorithm for their solution. Mathematical modeling was used to research the virus transmission situation and to develop a heuristic algorithm for the solution of the obtained mathematical model. The programming, the numerical experiments and the figures were constrained in MATLAB. The numerical experiments obtained for some cases show the dependence between the number of new infected with non-compliance of the recommendations for social distancing and the use of personal protection elements. The model is open to additions and improvements and may be of interest to support the decisions making process of the health and administrative authorities. The algorithm solves the proposed mathematical model to track virus transmission when the recommended safe and secure distances are not fulfilled. The application of the algorithm allows to propose controls in complex and unpredictable situations of epidemic development in population concentrations, so it can be used to improve the quality of proactive medical measures and other related decisions. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)