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The most severe failures in power grids are often characterized as cascading failures where an initial event triggers consequent failures all along the grid often leading to blackouts. Upon identifying a failure and its cascade potential, timely control actions should be performed by the grid operators to mitigate the effect of the cascade. These actions have to be delivered to one or more control devices, creating a dependency between the power grid and its control network. This paper examines the dependency of the operation of the power grid on the control network. Different from literature studies on failure control, our dependency model captures the impact of networking parameters. We formulate an algorithmic model that describes the impact of this dependency on cascade control. Based on this model, we propose an efficient cascade control algorithm using load shedding with consideration of delays in the communication network for power grids. Finally, we evaluate the impact of the power-communication network dependency with uncontrolled grids, ideal/simple control grids and our proposed control scheme. The results demonstrate that the proposed algorithm can significantly reduce the failure of power lines while sustaining larger power demand for users.

This research presents a 100% renewable energy (RE) scenario by 2050 with a high share of electric vehicles on the grid (V2G) developed in Ecuador with the support of the EnergyPLAN analysis tool. Hour-by-hour data iterations were performed to determine solutions among various features, including energy storage, V2G connections that spanned the distribution system, and long-term evaluation. The high participation in V2G connections keeps the electrical system available; meanwhile, the high proportions of variable renewable energy are the pillar of the joint electrical system. The layout of the sustainable mobility scenario and the high V2G participation maintain the balance of the electrical system during most of the day, simplifying the storage equipment requirements. Consequently, the influence of V2G systems on storage is a significant result that must be considered in the energy transition that Ecuador is developing in the long term. The stored electricity will not only serve as storage for future grid use. Additionally, the V2G batteries serve as a buffer between generation from diversified renewable sources and the end-use stage.

AbstractNumerical study of the influence of Prandtl number on free convection flow phenomena in a solar collector having glass cover plate and sinusoidal absorber is done. The working fluid is water-Al2O3 nanofluid. The cover plate has initially constant temperature Th, while bottom absorber is at temperature Tc, with Th > Tc. The remaining walls are considered adiabatic. By Penalty Finite Element Method the governing differential equations with boundary conditions are solved. The effect of the Prandtl number on the flow pattern and heat transfer has been depicted. Comprehensive average Nusselt number, average temperature and mean velocity inside the collector are presented as a function of the governing parameter mentioned above. The highest Pr causes the greatest heat transfer. The enhancing performance of heat transfer rate is more effective for the water-Al2O3 nanofluid than the base fluid.

The use of renewable energy in Latin America has increased significantly in recent years as a result of social pressure due to the negative effects generated by the use of polluting energy. However, there is still limited empirical evidence on the effect of clean energy on the output. The objective of this research is to examine the causal link among the growth rates of sustainable energy consumption, non-sustainable energy and the real per capita output in Latin America, a region with a high potential to generate clean energy. We used Pedroni (1999) and Westerlund (2007) cointegration techniques, and Dumitrescu and Hurlin (2012) causality test to evaluate the relationship among the variables. In order to evaluate the strength of the cointegration vector, we applied the dynamic ordinary least squares for individual countries and the panel dynamic ordinary least squares model for country groups. We find robust empirical evidence that suggests that the growth rate of renewable energy consumption, non-renewable energy and the rate of growth of real per capita output have a short-term and long-term equilibrium relationship. The force of the cointegration vector among the output and the renewable energy is more forceful in the countries of medium-high and medium-low incomes. The cointegration vector among the output and non-renewable energy is stronger in high-income countries. The results of the causality test suggest that renewable energy and the real per capita output have a bidirectional relationship in low-middle income countries. The output causes renewable energy in all groups of countries. Likewise, there is a unidirectional causality from the real per capita output towards non-renewable energy. One possible policy implication derived from this research is that high-income countries in the region should look for alternative sources of energy to achieve sustainable growth, and medium-high and medium-low income countries should encourage the use of energy clean, which does not limit the economic growth. Keywords: Energy. output. Cointegration. Causality. Panel data. Latin America, JEL classification: F43, P28, C23

En este trabajo, se ha investigado el impacto de seis capas diferentes de recubrimiento antirreflectante (ARC) utilizando el software de simulación PC1D. La simulación muestra que el rango de 500–700 nm sería adecuado para diseñar un ARCO. Diseñando un ARCO de nitruro de silicio de una sola capa (Si3N4) para una longitud de onda de 600 nm y con un espesor de 74.257 nm, se ha simulado una célula solar de silicio con una eficiencia del 20.35%. Le sigue muy de cerca una célula solar de silicio con una eficiencia del 20,34% con una capa de ARCO de óxido de zinc (ZnO) de 74,87 nm de espesor. Se ha observado un aumento significativo en la eficiencia al aplicar ARC con respecto a no aplicar ningún tipo de ARC. Después de un modelado eficiente de las células solares, se está logrando una eficiencia óptima del 20,67% mediante el uso de la pasivación superficial de SiO2 y la capa de ARCO de Si3N4. Los efectos sobre la tensión, la corriente, la eficiencia fotovoltaica, la reflectividad y la eficiencia cuántica externa debidos a los ARC también están representados en este trabajo. Dans ce travail, l'impact de six couches différentes de revêtement antireflet (ARC) a été étudié à l'aide du logiciel de simulation PC1D. La simulation montre que la plage de 500–700 nm serait appropriée pour concevoir un ARC. En concevant un ARC de nitrure de silicium monocouche (Si3N4) pour une longueur d'onde de 600 nm et une épaisseur de 74,257 nm, une cellule solaire en silicium avec une efficacité de 20,35% a été simulée. Très étroitement suivie par une cellule solaire en silicium à 20,34 % d'efficacité avec une couche d'ARC en oxyde de zinc (ZnO) de 74,87 nm d'épaisseur. Une augmentation significative de l'efficacité a été observée en appliquant L'ARC par rapport à l'absence d'application de tout type d'ARC. Après une modélisation efficace des cellules solaires, une efficacité optimale de 20,67 % est obtenue en utilisant la passivation de surface SiO2 et la couche D'ARC Si3N4. Les effets sur la tension, le courant, l'efficacité photovoltaïque, la réflectivité et l'efficacité quantique externe dus aux ARC sont également représentés dans ce travail. In this work, the impact of six different anti-reflection coating (ARC) layers has been investigated using PC1D simulation software. Simulation shows that the range of 500–700 nm would be suitable for designing an ARC. Designing a single-layer silicon nitride (Si3N4) ARC for 600 nm wavelength and with a thickness of 74.257 nm, a silicon solar cell with 20.35% efficiency has been simulated. Very closely followed by a 20.34% efficient silicon solar cell with 74.87 nm thick zinc oxide (ZnO) ARC layer. Significant increase in efficiency has been observed by applying ARC in respect to not applying any kind of ARC. After efficient solar cell modeling, optimum efficiency of 20.67% is being achieved by using SiO2 surface passivation and Si3N4 ARC layer. The effects on voltage, current, photovoltaic efficiency, reflectivity and external quantum efficiency due to ARCs are also represented in this work. في هذا العمل، تم التحقيق في تأثير ست طبقات مختلفة من الطلاء المضاد للانعكاس (ARC) باستخدام برنامج محاكاة PC1D. تظهر المحاكاة أن النطاق من 500–700 نانومتر سيكون مناسبًا لتصميم القوس. تصميم قوس نيتريد السيليكون أحادي الطبقة (Si3N4) بطول موجي 600 نانومتر وبسمك 74.257 نانومتر، تمت محاكاة خلية شمسية من السيليكون بكفاءة 20.35 ٪. تليها عن كثب خلية شمسية من السيليكون فعالة بنسبة 20.34 ٪ مع طبقة قوسية من أكسيد الزنك بسماكة 74.87 نانومتر (ZnO). لوحظت زيادة كبيرة في الكفاءة من خلال تطبيق القوس فيما يتعلق بعدم تطبيق أي نوع من القوس. بعد نمذجة الخلايا الشمسية بكفاءة، يتم تحقيق الكفاءة المثلى بنسبة 20.67 ٪ باستخدام تخميل سطح SiO2 وطبقة Si3N4 القوسية. يتم تمثيل التأثيرات على الجهد والتيار والكفاءة الكهروضوئية والانعكاسية والكفاءة الكمية الخارجية بسبب ARCs أيضًا في هذا العمل.

More and more renewable energy sources are integrated into power grids, leading to a power electronic-based low-inertia power system. The grid-forming (GFM) inverter is an effective method for improving the inertia of the system. However, with the increased GFM inverters in the system, how the multiple control parameters affect the frequency response is still not clear. In this study, first, the power-phase model of the power grid is established; then, a small-signal distributed frequency model of the GFM inverter-based power system is established associating with the power-phase model of the power grid and the power-frequency model of the GFM inverter. Based on the proposed model, the influence of the multiple parameters to the frequency response is analyzed. It is concluded that both the inertia and damping coefficient affect the settling time, overshoot, and oscillation of the frequency. Finally, the simulation results verify the proposed model and the conclusion.

This paper presents a finite control-set model predictive control (FCS-MPC) based technique to reduce the switching loss and frequency of the on-grid PV inverter by incorporating a switching frequency term in the cost function of the model predictive control (MPC). In the proposed MPC, the control objectives (current and switching frequency) select an optimal switching state for the inverter by minimizing a predefined cost function. The two control objectives are combined with a weighting factor. A trade-off between the switching frequency (average) and total harmonic distortion (THD) of the current was utilized to determine the value of the weighting factor. The switching, conduction, and harmonic losses were determined at the selected value of the weighting factor for both the proposed and conventional FCS-MPC and compared. The system was simulated in MATLAB/Simulink, and a small-scale hardware prototype was built to realize the system and verify the proposal. Considering only 0.25% more current THD, the switching frequency and loss per phase were reduced by 20.62% and 19.78%, respectively. The instantaneous overall power loss was also reduced by 2% due to the addition of a switching frequency term in the cost function which ensures a satisfactory empirical result for an on-grid PV inverter.