DYNA ENERGIA Y SOSTENIBILIDAD

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EISSN : 2254-2833
Published by: Publicaciones DYNA (10.6036)
Total articles ≅ 116
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Rosalia Belen Revelo Sarango,
Published: 4 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10264

Abstract:
This article describes an algorithm for an adaptive distance protection in a sub-transmission system considering operating conditions with changes in the topology due to an abnormal condition, electrical failure or a natural disaster, includes the effect of adjacent generation in the distance relay protection zones, with the incorporation of renewable energies in mixed participation. Two scenarios are proposed, in the first case occurred a contingency, and the transmission systems changes the initial topology. Protections are automatically reparametrized. The second case includes the income of renewable energy generation in a specific point of power electrical Systems. Protections are automatically recalculated. The objective of an automatic coordination permit to operator to restore the sensitivity, selectivity and reliability the electrical protection system in the lowest time. Keywords: Adaptive distance relay, renewable energy, distance protection, infeed effect..)
Published: 4 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10293

Abstract:
This work presents an application of the Risk-Sensitive (R-S) control with tracking applied to a stochastic nonlinear system which models the operation of an electronic expansion valve (EEV) in a conventional evaporator. A novel dynamical stochastic equation represents the mathematical model of the evaporator system. The R-S stochastic optimal problem consists of the design of an optimal control u(t) such that the state reaches setpoint values (SP) and minimizes the exponential quadratic cost function. The presence of disturbances and errors in the sensor measurements is represented by Gauss white noise in the state equation, with the coefficient v(e/(2?^2 )) . One novel characteristic in this proposal is that the coefficient of the control into the state equation contains the state term. The error and exponential quadratic cost function show that the R-S control has a better performance versus the classical PID (Proportional, Integral Derivative) control. Key Words: Optimal Risk-Sensitive control with tracking, modelling of the evaporator.
Luis Cisneros Villalobos, , Alina Martinez Oropeza, ,
Published: 1 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10379

Abstract:
This article shows the analysis for load transfer without interruption between two 23 kV distribution feeders. This procedure is not common in this type of system and requires paying primary attention to the characteristics of the electrical network for its application. The distribution circuits discussed here have their own power substation with different voltage levels. The information obtained from a state estimator, the contingency conditions, the electrical parameters of impedances and network configuration allow to carry out the simulation of the load transfer with the Alternative Transients Program software. From the simulation it is shown that load transfer without interruption is possible as long as certain operating conditions are met in the power and distribution networks. The dependence of the transfer on the voltage levels, angular phase shift of voltages and strength of the electrical network is shown, represented by its thevenin impedance at the interconnection point. The results found from the simulation indicate that the success of the interconnection is mainly a function of the electrical strength of the power substations and the phase sequence of the power transformer at the load transfer point. Certain percentages of variation of voltage and currents of the feeders are defined that must not be exceeded. The operational aspects proposed here serve as a basis to have a general interconnection procedure between distribution feeders where special attention is required in the continuity of the service due to the high expectation in the satisfaction of the user of the electrical network. Keywords: feeder, state estimator, medium voltage, power system, load transferring.
Adriana Mercedes Marquez Romance, Edilberto Guevara Perez, Abel Mejia Marcacuzco
Published: 1 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10470

Abstract:
This paper describes the global situation of water resources and the need to propose a prospective on integrated water management. An analysis of the water crisis, the development of the administration and experiences on the application of management models is carried out. General guidelines are proposed to establish an integrated management plan. Finally, the water management model developed for Peru is summarized. Keywords: Water crisis; Water management; integrated water management model; integrated water management plan; water resources
Juan Franquelo Soler, , , , Francisco Javier Soto Villaran
Published: 1 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10341

Abstract:
Natural ventilation has become one of the most effective and sustainable strategies to address COVID-19 in confined spaces. Air intake through windows and other openings improves the Indoor Air Quality (IAQ) of a classroom, decreases the likelihood of respiratory disease transmission with an adequate social distance of about 1.5 m and is affordable in terms of energy consumption. In this study, a comparison of CO2 concentration, wind speed, number of people, type of ventilation and window surfaces of a school in a Mediterranean climate is carried out for 4 different cases of opening. For this purpose, CO2 levels were measured in different classrooms with different window openings (33%, 67%, 81%, 81%). (33%, 67%, 81% and 100% respectively). In addition, three types of ventilation (cross ventilation, partial cross ventilation and multidirectional ventilation) were analyzed in a time period between February and March 2021. The results show an interaction between CO2 levels and the type of ventilation. Thus, the fact that the window surface is a critical factor in reducing CO2 concentrations was determined, considering that the distance between students was approximately 1.5 m. Therefore, the orientation of buildings towards the predominant wind direction and the Window to Floor Ratio (WFR) should be reconsidered in new constructions. Keywords: natural ventilation, indoor air quality, carbon dioxide (CO2) concentration, school, WFR.
, Fernando Garcia Jimenez
Published: 1 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10572

Abstract:
Disaster risk is a social process characterized by the coincidence, at the same time and place, of potentially dangerous physical phenomena and socioeconomic elements exposed to these phenomena in a condition of vulnerability. Therefore, forces derived from society and nature are at work in determining the existence of risk and its levels. Neither of these two elements are stable or permanent over time. They undergo continuous changes and variations. In this sense, this work presents a system dynamics simulation model of the degree of preparedness in the disaster risk management process at the level of an autonomous community. All this with the aim of raising awareness of the problematic of the social and economic impact of this type of physical phenomena. This model is applied to the context of the Filomena storm (natural disaster that took place in Spain on January 7, 2021) in order to validate its usefulness in a real case study. The model is implemented in two simulations and results are compared. In the first simulation, actual data associated with the policies, reports and descriptions of the community of Madrid during the 120 days prior to the event are introduced according to certain variables within the Sendai risk reduction framework (forecast errors, available information, CO2 emissions, recycling and commodity index prices). With that, the value " of the "Degree of Preparedness" achieved by the capital before the storm is obtained. In the second simulation, these input variables of the model are modified to analyze the effect it would have had on the "Degree of Preparedness". Key Words: Simulation, Vensim, Risk Management, Storm Filomena, Natural Disasters.
Juan Franquelo Soler, , , , Francisco Javier Soto Villaran
Published: 1 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10448

Abstract:
In 1979, the Spanish government implemented the standard “Basic Building on Thermal Conditions in Buildings NBE-CT-79”. It was then that the first requirements regarding insulation and thermal properties of materials were established to reduce energy consumption. The Mediterranean climate has influenced that insufficient attention has been paid to building insulation. In dwellings before 1979, it was detected that there is a feeling of lack of comfort. However, it is not so well known that there is a lack of airtightness in these dwellings, which may contribute to discomfort. The aim of the article is to find out if the air that enters spontaneously by infiltration produces effects similar to those of a displacement diffuser and how it affects thermal comfort. Thus, cold air would flow down the walls and be evenly distributed on the floor in winter, creating a homogeneous layer and feeling discomfort. Air infiltration measurements were carried out in 5 dwellings with an anemometer and infrared thermography to support the initial hypothesis. The Fanger Method, provided by the Polytechnic University of Valencia, was used to determine the thermal sensation produced. It was found that the cold air descended slowly and continuously to the ground in a similar way to a displacement diffuser, remaining for hours and being influential in the thermal conditions of the rooms and the lack of comfort of its occupants. Keywords: air infiltration, discomfort, thermography, displacement difusión, energy efficiency.
, Sait Omar Cristerna Sosa,
Published: 1 January 2022
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 11; https://doi.org/10.6036/es10400

Abstract:
In Sinaloa, agricultural and livestock practices are extensive but proportionally generate organic wastes that subsequently produce greenhouse gases and negatively impact water bodies. In this research, a laboratory-scale up-flow anaerobic reactor was configured and evaluated to treat combined agricultural and livestock wastes. Subsequently, the quality and yield of the biogas were used to make an energetic and economic comparison with Liquefied Petroleum Gas (LPG). The results were also projected for the energy needs of the pilot community from which the waste was obtained. The reactor used was a 2.4 L reactor operated continuously at 45±2 °C and HRT of 7.2 d, with an organic load of 15000 mg/L. Carbon/nitrogen ratios of 25:1 and 32:1 were evaluated. With the 25:1 ratio, 1650 mL/d of biogas were obtained. With this ratio, greater stability was observed, and a higher proportion of methane. On average, 70% was methane (once stabilization was reached), converting it into biofuel. The projection made for Sinaloa is that 59.65 m3 of methane could be obtained per year, which is equivalent to $2.25 million per year. All the information generated serves as a precedent for large-scale technical and economic feasibility studies. All these studies will allow the integral use of agricultural industry waste, mainly in rural communities, which will also improve the population's quality of life. Keywords: methane yield, biofuel, agricultural wastes management, methane, Upflow Anaerobic Sludge Blanket, carbon/nitrogen ratio
Published: 1 January 2021
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 10; https://doi.org/10.6036/es10113

Abstract:
This article analyses the effect of the closure of the Spanish coal-fired power stations on the price and quantity of energy sold in the daily electricity market. The comparative statics analysis is based on the hourly data of energy offer and demand bids published by the OMIE (Operator of the Iberian Energy Market) and made by the participants in the daily electricity market during the year 2018. Our analysis does not require any simulation of the market supply and demand curves, since they are obtained by aggregation using real data from the wholesale market. The main conclusion of our analysis is that, after the closure of the coal-fired stations, the hourly price of energy would increase 12,06% on average while the average amount of energy would decrease 2,57%. Keywords: Price of electricity; coal plants; ecological transition; supply and demand surpluses; renewable energy.
Ignacio Muguruza Velilla, Eneko Mola Sanz, Marlon Gallo Torres, Aitzol Ugartemendia Iturrizar, , David Cabezuelo Romero
Published: 1 January 2021
DYNA ENERGIA Y SOSTENIBILIDAD, Volume 10; https://doi.org/10.6036/es10295

Abstract:
This study focuses on a comparison between different maximum power extraction controls for a small wind turbine application. In this case, a vertical axis wind turbine (VAWT) coupled to a permanent magnet synchronous generator (PMSG) is used. The analysis is performed for variable winds, so that a real small wind turbine application is simulated. An experimental platform and a wind tunnel are used to recreate the different wind profiles. Diverse controls are compared, a "classical" MPPT, a hybrid Perturb & Observe control and a fuzzy control. Artificial intelligence allows the creation of control algorithms that are not bound by the mechanical parameters of the wind turbine, thus avoiding the need to characterize the wind turbine and define the maximum power curve. It is determined that, for almost constant wind profiles, the hybrid Perturb & Observe extracts more energy. However, for the same profile with greater variability, the fuzzy controller extracts more energy.
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