Fast Adaptive Robust Differentiator Based Robust-Adaptive Control of Grid-Tied Inverters with a New L Filter Design Method

In this research, a new nonlinear and adaptive state feedback controller with a fast-adaptive robust differentiator is presented for grid-tied inverters. All parameters and external disturbances are taken as uncertain in the design of the proposed controller without the disadvantages of singularity and over-parameterization. A robust differentiator based on the second order sliding mode is also developed with a fast-adaptive structure to be able to consider the time derivative of the virtual control input. Unlike the conventional backstepping, the proposed differentiator overcomes the problem of explosion of complexity. In the closed-loop control system, the three phase source currents and direct current (DC) bus voltage are assumed to be available for feedback. Using the Lyapunov stability theory, it is proven that the overall control system has the global asymptotic stability. In addition, a new simple L filter design method based on the total harmonic distortion approach is also proposed. Simulations and experimental results show that the proposed controller assurances drive the tracking errors to zero with better performance, and it is robust against all uncertainties. Moreover, the proposed L filter design method matches the total harmonic distortion (THD) aim in the design with the experimental result

Optimal Size of a Smart Ultra-Fast Charging Station

An ever-increasing penetration of electric vehicles (EVs) on the roads inevitably leads to an ever-stringent need for an adequate charging infrastructure. The emerging ultra-fast charging (UFC) technology has the potential to provide a refueling experience similar to that of gasoline vehicles; hence, it has a key role in enabling the adoption of EVs for medium-long distance travels. From the perspective of the UFC station, the differences existing in the EVs currently on the market make the sizing problem more challenging. A suitably conceived charging strategy can help to address these concerns. In this paper, we present a smart charging station concept that, through a modular DC/DC stage design, allows the split of the output power among the different charging ports. We model the issue of finding the optimal charging station as a single-objective optimization problem, where the goal is to find the number of modular shared DC/DC converters, and where the power rate of each module ensures the minimum charging time and charging cost. Simulation results show that the proposed solution could significantly reduce the required installed power. In particular, they prove that with an installed power of 800 kW it is possible to satisfy the needs of a UFC station composed of 10 charging spots

Robust 24 Hours ahead Forecast in a Microgrid: A Real Case Study

Forecasting the power production from renewable energy sources (RESs) has become fundamental in microgrid applications to optimize scheduling and dispatching of the available assets. In this article, a methodology to provide the 24 h ahead Photovoltaic (PV) power forecast based on a Physical Hybrid Artificial Neural Network (PHANN) for microgrids is presented. The goal of this paper is to provide a robust methodology to forecast 24 h in advance the PV power production in a microgrid, addressing the specific criticalities of this environment. The proposed approach has to validate measured data properly, through an effective algorithm and further refine the power forecast when newer data are available. The procedure is fully implemented in a facility of the Multi-Good Microgrid Laboratory (MG(Lab)(2)) of the Politecnico di Milano, Milan, Italy, where new Energy Management Systems (EMSs) are studied. Reported results validate the proposed approach as a robust and accurate procedure for microgrid applications

El paradigma de la calidad normativa en el diseño de cursos en línea masivos y abiertos

Los cursos Massive Open On Line Courses (en adelante MOOC) se han considerado en la literatura divulgativa y científica como una revolución con un gran potencial en el mundo educativo y formativo. En este sentido, existe un consenso en la comunidad científica sobre la importancia y popularidad del movimiento, principalmente, por su alcance internacional y la oportunidad de ofrecer una formación de calidad a través de prestigiosas instituciones a cualquier estudiante, lo que hace muy poco parecía estar destinado a las élites.Sin embargo, al mismo tiempo, aparecen discrepancias y cuestionamientos sobre el valor pedagógico y el alcance que tendrá el movimiento en la Educación Superior. Las dudas se centran principalmente en el valor que la comunidad científica otorga al movimiento desde su incidencia en el panorama socio-formativo y que polarizan posturas desde posicionamientos que lo consideran un movimiento destructivo hacia otras que lo tildan de profundamente renovador y creativo. Así pues, el universo de los MOOC es objeto de reflexión didáctica y formativa entre diferentes autores y por instituciones de Educación Superior en el mundo globalizado, pero todavía es necesaria unas dimensiones e implicaciones de la visión evaluadora de los mismos que deben ser valoradas y analizadas desde diferentes puntos de vista. En este artículo se presenta un panorama descriptivo del diseño pedagógico de los cursos MOOC y la posible evaluación de su calidad a través del ajuste de los estándares de la Norma UNE (acrónimo de Una Norma Española) 66181:2012 sobre la Gestión de la Calidad de la Formación Virtual. En esta adaptación de la norma, no se ha tomado la información de los niveles de calidad de acuerdo a un sistema de representación de estrellas acumulativas. Es decir, se introducen indicadores de distintas rúbricas de niveles de calidad sin ser acumulativos, de tal forma que cada estándar de calidad se podría valorar de forma independiente y no tendría que contener la suma de los indicadores de los niveles anteriores. Por tanto, manteniendo los términos de la Norma UNE, se diseña un modelo de valoración de la calidad normativa, tanto cualitativa como cuantitativa, en el diseño de cursos MOOCmanteniendo las dimensiones que abarcan los factores de satisfacción de la formación virtual: empleabilidad, metodología de aprendizaje y accesibilidad.In the scientific and informative literature Massive Open On Line Courseshave been considered as a revolution with great potential in the education and training world. In this sense, this movement has been of interest worldwide due to its great potential to offer a free training, quality and accessible to all users regardless of their country of origin, prior training and without the need to pay for registration. Since early 2010, the arrival of these courses began to be viewed from a more academic perspective when different prestigious universities began their mass activities, among others, Stanford, Harvard, Massachusetts Institute of Technology, the University of Pennsylvania and the Toronto University. It there is agreement in the scientific community about the importance and popularity of this movement, mainly by its international scope and the opportunity to provide a quality education through prestigious institutions, which recently was destined to elite organizations. However, there are discrepancies and questions about the pedagogical value and scope will move in Higher Education. Doubts are mainly focused on the value that the scientific community gives the movement from its impact on the socio-educational field and facing positions from authors who consider a destructive movement toward others define it as refreshing and creative action. In this sense, the universe of Massive Open On Line Courses is the subject of educational and training reflection among different authors and institutions of higher education in the globalized world, but the dimensions and implications of the evaluative view of these courses is necessary since different views. This article provides a descriptive overview of the instructional design of the Massive Open On Line Courses and the possible assessment of their quality is presented through setting standards on UNE 66181:2012 Quality Management of Virtual Training

The paradigm of normative quality in the design of massive open online courses

Los cursos Massive Open On Line Courses (en adelante MOOC) se han considerado en la literatura divulgativa y científica como una revolución con un gran potencial en el mundo educativo y formativo. En este sentido, existe un consenso en la comunidad científica sobre la importancia y popularidad del movimiento, principalmente, por su alcance internacional y la oportunidad de ofrecer una formación de calidad a través de prestigiosas instituciones a cualquier estudiante, lo que hace muy poco parecía estar destinado a las élites.Sin embargo, al mismo tiempo, aparecen discrepancias y cuestionamientos sobre el valor pedagógico y el alcance que tendrá el movimiento en la Educación Superior. Las dudas se centran principalmente en el valor que la comunidad científica otorga al movimiento desde su incidencia en el panorama socio-formativo y que polarizan posturas desde posicionamientos que lo consideran un movimiento destructivo hacia otras que lo tildan de profundamente renovador y creativo. Así pues, el universo de los MOOC es objeto de reflexión didáctica y formativa entre diferentes autores y por instituciones de Educación Superior en el mundo globalizado, pero todavía es necesaria unas dimensiones e implicaciones de la visión evaluadora de los mismos que deben ser valoradas y analizadas desde diferentes puntos de vista. En este artículo se presenta un panorama descriptivo del diseño pedagógico de los cursos MOOC y la posible evaluación de su calidad a través del ajuste de los estándares de la Norma UNE (acrónimo de Una Norma Española) 66181:2012 sobre la Gestión de la Calidad de la Formación Virtual. En esta adaptación de la norma, no se ha tomado la información de los niveles de calidad de acuerdo a un sistema de representación de estrellas acumulativas. Es decir, se introducen indicadores de distintas rúbricas de niveles de calidad sin ser acumulativos, de tal forma que cada estándar de calidad se podría valorar de forma independiente y no tendría que contener la suma de los indicadores de los niveles anteriores. Por tanto, manteniendo los términos de la Norma UNE, se diseña un modelo de valoración de la calidad normativa, tanto cualitativa como cuantitativa, en el diseño de cursos MOOCmanteniendo las dimensiones que abarcan los factores de satisfacción de la formación virtual: empleabilidad, metodología de aprendizaje y accesibilidad.In the scientific and informative literature Massive Open On Line Courseshave been considered as a revolution with great potential in the education and training world. In this sense, this movement has been of interest worldwide due to its great potential to offer a free training, quality and accessible to all users regardless of their country of origin, prior training and without the need to pay for registration. Since early 2010, the arrival of these courses began to be viewed from a more academic perspective when different prestigious universities began their mass activities, among others, Stanford, Harvard, Massachusetts Institute of Technology, the University of Pennsylvania and the Toronto University. It there is agreement in the scientific community about the importance and popularity of this movement, mainly by its international scope and the opportunity to provide a quality education through prestigious institutions, which recently was destined to elite organizations. However, there are discrepancies and questions about the pedagogical value and scope will move in Higher Education. Doubts are mainly focused on the value that the scientific community gives the movement from its impact on the socio-educational field and facing positions from authors who consider a destructive movement toward others define it as refreshing and creative action. In this sense, the universe of Massive Open On Line Courses is the subject of educational and training reflection among different authors and institutions of higher education in the globalized world, but the dimensions and implications of the evaluative view of these courses is necessary since different views. This article provides a descriptive overview of the instructional design of the Massive Open On Line Courses and the possible assessment of their quality is presented through setting standards on UNE 66181:2012 Quality Management of Virtual Training

Multi-Objective Optimization of PV and Energy Storage Systems for Ultra-Fast Charging Stations

The installation of ultra-fast charging stations (UFCSs) is essential to push the adoption of electric vehicles (EVs). Given the high amount of power required by this charging technology, the integration of renewable energy sources (RESs) and energy storage systems (ESSs) in the design of the station represents a valuable option to decrease its impact on the grid and the environment. Therefore, this paper proposes a multi-objective optimization problem for the optimal sizing of photovoltaic (PV) system and battery ESS (BESS) in a UFCS of EVs. The proposed multi-objective function aims to minimize, on one side, the annualized cost of the station, and on the other side, the produced pollutant emissions. The decision variables are the number of PV panels and the capacity of the ESS to be installed. The optimization problem is reduced to a single-objective problem by applying the linear scalarization method. Then the equivalent single-objective function is optimized through a genetic algorithm (GA). The proposed optimization framework is applied to a study case and the results prove that PV and ESS could lead to a significant reduction of both the annualized cost and the pollutant emissions. Finally, a sensitivity analysis is also presented to validate the effectiveness of the proposed solution

Evaluating the inertia of the Jordanian power grid

The increasing penetration of renewable energy sources in power grids has resulted in the need for a comprehensive evaluation of their impact on the dynamic behavior of the power system, including its inertia. This study aimed to evaluate the inertia of the current Jordanian power system at different penetration levels of renewable energy sources using DIgSILENT PowerFactory simulation software. In this study, the value of the constant inertia was calculated to be 8.755 s. The results were analyzed to determine the effect of renewable energy penetration on the inertia of the power system. The findings provide valuable information for the development of control strategies for integrating renewable energy sources into the Jordanian power system, ensuring stability and reliability in the power system operation. This study contributes to the understanding of the impact of renewable energy sources on power system inertia and supports the development of renewable energy integration strategies.13 página

Real-Time Implementation of qZSC for MVDC to Microgrids Link

Nowadays, power systems require new solutions to integrate renewable energies. In this paper, microgrids linked to MVDC are proposed through quasi-impedance-source converters to improve system reliability. Several prototypes are implemented using real-time platforms to analyze the system behavior, but the real-time implementation of the shoot-through state of the qZSC requires a very low time-step and sample time, which is not easy to achieve. The results obtained with these prototypes are included. Finally, a satisfactory solution is presented, implementing the power system in Typhoon HIL-402, the qZSC control in dSPACE MicroLabBox, and generating the gate signals in the FPGA included in the MicroLabBox platform. © 2022, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved

Diseño IoT y validación de sistema de medida para generación fotovoltaica

The use of photovoltaic (PV) systems for electricity generation is constantly growing in Brazil. With the reduction in the price of PV modules and the implementation of the electric power compensation system by the power distributor, the consumer is investing in PV microgeneration to reduce the electricity bill. This article aims to develop an embedded system in the context of the Internet of Things (IoT). Having an IoT monitoring system applied to a grid-connected PV system in an educational institution helps teach concepts such as IoT and PV generation. The system is based on the ESP32 development board for acquiring DC voltage and current generated by a 1.35 kWp PV system connected to the grid and installed at the IFCE. This proposal offers a low-cost educational solution using open source and programmable hardware, which sends the data to a database in the cloud, enabling remote access worldwide. Then, using the data analysis methodology, it was possible to validate the values measured with the inverter installed with an error below 1% for the voltage and current acquired during one day. With this result, it is concluded that the designed IoT system can be used for measurement in PV systems.El uso de sistemas fotovoltaicos (FV) para la generación de electricidad está en constante crecimiento en Brasil. Con la reducción del precio de los módulos FV y la implementación del sistema de compensación de energía eléctrica por parte del distribuidor de energía, el consumidor está invirtiendo en microgeneración FV para reducir la factura de energía. El objetivo del presente artículo es desarrollar un sistema embebido en el contexto de Internet de las cosas (IoT). Tener un sistema de monitoreo IoT aplicado a un sistema FV conectado a la red en una institución educativa ayuda a enseñar conceptos tanto de IoT como de generación FV. El sistema se basa en la placa de desarrollo ESP32 para la adquisición de tensión y corriente continua generada por un sistema FV de 1,35 kWp conectado a la red e instalado en el IFCE. Esta propuesta ofrece una solución educativa de bajo costo, con código abierto y hardware programable, que envían los datos a una base de datos en la nube, lo que permite el acceso remoto desde cualquier parte del mundo. Posteriormente, con una metodología de análisis de datos fue posible validar los valores medidos con el inversor instalado con un error inferior al 1 % para la tensión y la corriente adquiridas durante un día. Con este resultado se concluye que el sistema IoT diseñado puede ser utilizado para la medición en sistemas FV

Foreign Object Detection for Electric Vehicle Wireless Charging

Wireless power transfer technology is being widely used in electric vehicle wireless-charging applications, and foreign object detection (FOD) is an important module that is needed to satisfy the transmission and safety requirements. FOD mostly includes two key parts: metal object detection (MOD) and living object detection (LOD), which should be implemented during the charging process. In this paper, equivalent circuit models of a metal object and a living object are proposed, and the FOD methods are reviewed and analyzed within a unified framework based on the proposed FOD models. A comparison of these detection methods and future challenges is also discussed. Based on these analyses, detection methods that employ an additional circuit for detection are recommended for FOD in electric vehicle wireless-charging applications