Anti-Islanding Detector based on a Robust PLL

As required by international standards, the distributed energy generators, connected to the grid by an inverter, have to detect an islanding condition within a suitable time interval. In this paper, a phase-locked loop (PLL), based on a third-order prediction-correction filter, is proposed to implement an islanding detector with reduced detection time. Such a feature is obtained using the estimation of the grid angular frequency and acceleration provided by the PLL with a negligible time delay. The proposed approach is implemented on an industrial grade DSP and validated through the experimental comparison among different detection methods, such as rate of change of frequency (ROCOF) and Slip Mode frequency Shift (SMS). The combined use of ROCOF and SMS is also illustrated and discussed

Cascaded multilevel inverter for vertical stabilization and radial control power supplies

This paper presents the analysis and topology selection for the power supplies of the two DTT equatorial in-vessel coils for plasma vertical stabilization and fast radial control. The physics requirements and assumptions are analyzed in order to identify the system specifications. Since the basic configuration with two independent power supply circuits is too vulnerable to fast plasma events as disruptions, a circuit configuration including both coils is introduced. Two successive solutions, with three or two power converters, are proposed to supply such a common circuit. The adopted topology, based on cascaded H-bridge converters with IGBTs, is simulated by means of a simplified circuital model, that also consider the plasma disruptions. The simulation results show that vertical stabilization and fast radial control functions can be simultaneously achieved with two identical power converters and a passive imbalance branch by using a specific current control scheme

Grid-connected Microgrids to Support Renewable Energy Sources Penetration

Abstract Distributed generation systems and microgrids are instrumental for a greater penetration of renewables to achieve a substantial reduction on carbon emissions. However, microgrids performances and reliability strongly depend on the continuous interaction between power generation, storage and load requirements, highlighting the importance in developing a proper energy management strategy and the relative control system. In this work a Model predictive Control (MPC) strategy, based on a Mixed Linear Integer Programming framework, has been applied to a residential microgrid case. Theoretical results obtained confirm that grid connected microgrids have potential capabilities in grid balancing allowing for a larger penetration of fluctuating renewable energy sources and thus producing economic benefits for both end-user and grid operators. A microgrid test bench to reproduce previous microgrid model is also presented in the paper. The experimental setup has been used to validate results obtained from simulation. Results obtained confirm the potential of this solution and its real applicability

E-kayak: A Wireless DAQ System for Real Time Performance Analysis

Abstract The use of microelectronic measurement systems properly designed for sport performance monitoring is, in recent years, increasingly common to give helpful feedback in training of professional athletes. Different are the systems today available, some of them make use of video analysis while others are based on the measure of specific kinematic or dynamic parameters. In this paper, we present a study on a new portable data acquisition system (E-kayak – ApLab Rome Italy) for real time monitoring of the boat and paddling dynamics. The system gives real time feedback to the athlete during the training session. Moreover, the training data can then be downloaded to a PC for further analysis from the coach. The acquired data can help evaluating the paddling technique and spotting technical flaws, to improve performance. A first prototype of the system has been manufactured and at the moment is still in the testing phase. Some results of the preliminary tests are presented in this paper

Modulated model predictive control for active split DC-bus 4-leg power supply

This paper proposes a constant switching frequency Finite Control Set Model Predictive Control (FCS-MPC), formally Modulated FCS-MPC or M2PC, for a 4-leg inverter having an Active Split DC-bus on the fourth leg. The great advantage of MPC over linear control schemes is the very fast transient response it is capable to produce; it also can handle general constrained nonlinear systems with multiple inputs and outputs in a unified and clear manner. These features are highly valuable in power electronic converters used to supply the electrical utility loads in micro-grids. However, one of the main drawback of the MPC is its variable switching frequency, above all in system with accurately tuned output power filters (i.e. switching traps), which is the case when stable voltage waveforms with very low harmonic content are required. The proposed investigation relates with the application of a constant switching frequency variant of the MPC to a 4-leg inverter with a specifically tuned filter to assure high quality voltage supply even in case of non-linear and unbalanced loads

Predictive control for active split DC-bus 4-leg inverters

This paper proposes a Predictive Control, formally Dead-Beat (DBC), for a four-leg inverter having an Active Split DC-bus on the fourth leg and LC filters on phase-to-neutral outputs. Such a configuration permits to reduce the voltage ripple on the neutral point connected to inverter grounding. As only few control techniques have been investigated for Active Split DC-bus, the paper proposes to investigate the performance of DBC, which has been widely used for other power electronics applications. The main advantage of DBC over the classical PI or Resonant controller is that no tuning is required for control loop, while obtaining very fast transient response as well it can handle general constrained nonlinear systems with multiple inputs and outputs in a unified and clear manner. These features are highly valuable in power electronic converters used to supply the electrical utility loads in micro-grids. However, one of the main drawback of the DBC is the limited capabilities on harmonics compensations required when supplying unbalanced and non-linear loads. The paper presents continuous-time and discrete-time models of DBC applied to a four-leg VSI with Active Split DC-bus, highlighting the performance through simulation results as well as experimental tests

La Doctrina Contable y los marcos conceptuales para la normativa contable: aportes para un consenso generalizado de conceptos y definiciones clave necesarios para las Memorias de Sostenibilidad GRI G4

En el presente estudio se rescata que desde el año 2017 ha de ser aplicada la nueva Directiva 2014/95/UE en la Unión Europea, sobre divulgación de información no financiera y diversidad, informes también conocidos como de responsabilidad corporativa o de sostenibilidad, para organizaciones con más de 500 empleados, recomendándose directrices internacionales como la versión G4 de la Global Reporting Initiative (GRI), entre otras. Para Argentina se considera un estudio realizado sobre la opinión de los CEO, de las cien empresas más grandes, referida a la Sustentabilidad y que, desde el ámbito profesional contable, la Federación Argentina de Consejos Profesionales de Ciencias Económicas (FACPCE), aprueba en 2012 la Resolución Técnica (RT) Nº 36: Normas contables profesionales: Balance Social. El Mencionado Balance Social se compone por la memoria de sostenibilidad de la Global Reporting Initiative (GRI) y el Estado de Valor Económico Generado y Distribuido (EVEGyD). En 2015 GRI brinda su más reciente versión G4 que incluye una fe de erratas para corregir algunos problemas terminológicos y ambigüedades textuales, y FACPCE en 2016 aprueba la RT Nº 44, que actualiza la anterior RT Nº 36.In the present study it is recalled that since 2017 the new Directive 2014/95 / EU has to be applied in the European Union, on disclosure of non-financial information and diversity, reports also known as corporate responsibility or sustainability, for organizations with more than 500 employees, recommending international guidelines such as the G4 version of the Global Reporting Initiative (GRI), among others. For Argentina it is considered a study carried out on the opinion of the CEOs, of the hundred largest companies, referred to the Sustainability and that, from the professional accounting scope, the Argentine Federation of Professional Councils of Economic Sciences (FACPCE), approves in 2012 Technical Resolution (RT) No. 36: Professional Accounting Standards: Social Balance. The aforementioned Social Balance is made up of the sustainability report of the Global Reporting Initiative (GRI) and the State of Economic Value Generated and Distributed (EVEGyD). In 2015, GRI provides its most recent G4 version, which includes an erratum to correct some terminological problems and textual ambiguities, and FACPCE in 2016 approves RT No. 44, which updates the previous RT No. 36.Facultad de Ciencias Económica

La Doctrina Contable y los marcos conceptuales para la normativa contable: aportes para un consenso generalizado de conceptos y definiciones clave necesarios para las Memorias de Sostenibilidad GRI G4

En el presente estudio se rescata que desde el año 2017 ha de ser aplicada la nueva Directiva 2014/95/UE en la Unión Europea, sobre divulgación de información no financiera y diversidad, informes también conocidos como de responsabilidad corporativa o de sostenibilidad, para organizaciones con más de 500 empleados, recomendándose directrices internacionales como la versión G4 de la Global Reporting Initiative (GRI), entre otras. Para Argentina se considera un estudio realizado sobre la opinión de los CEO, de las cien empresas más grandes, referida a la Sustentabilidad y que, desde el ámbito profesional contable, la Federación Argentina de Consejos Profesionales de Ciencias Económicas (FACPCE), aprueba en 2012 la Resolución Técnica (RT) Nº 36: Normas contables profesionales: Balance Social. El Mencionado Balance Social se compone por la memoria de sostenibilidad de la Global Reporting Initiative (GRI) y el Estado de Valor Económico Generado y Distribuido (EVEGyD). En 2015 GRI brinda su más reciente versión G4 que incluye una fe de erratas para corregir algunos problemas terminológicos y ambigüedades textuales, y FACPCE en 2016 aprueba la RT Nº 44, que actualiza la anterior RT Nº 36.In the present study it is recalled that since 2017 the new Directive 2014/95 / EU has to be applied in the European Union, on disclosure of non-financial information and diversity, reports also known as corporate responsibility or sustainability, for organizations with more than 500 employees, recommending international guidelines such as the G4 version of the Global Reporting Initiative (GRI), among others. For Argentina it is considered a study carried out on the opinion of the CEOs, of the hundred largest companies, referred to the Sustainability and that, from the professional accounting scope, the Argentine Federation of Professional Councils of Economic Sciences (FACPCE), approves in 2012 Technical Resolution (RT) No. 36: Professional Accounting Standards: Social Balance. The aforementioned Social Balance is made up of the sustainability report of the Global Reporting Initiative (GRI) and the State of Economic Value Generated and Distributed (EVEGyD). In 2015, GRI provides its most recent G4 version, which includes an erratum to correct some terminological problems and textual ambiguities, and FACPCE in 2016 approves RT No. 44, which updates the previous RT No. 36.Facultad de Ciencias Económica

La Doctrina Contable y los marcos conceptuales para la normativa contable: aportes para un consenso generalizado de conceptos y definiciones clave necesarios para las Memorias de Sostenibilidad GRI G4

En el presente estudio se rescata que desde el año 2017 ha de ser aplicada la nueva Directiva 2014/95/UE en la Unión Europea, sobre divulgación de información no financiera y diversidad, informes también conocidos como de responsabilidad corporativa o de sostenibilidad, para organizaciones con más de 500 empleados, recomendándose directrices internacionales como la versión G4 de la Global Reporting Initiative (GRI), entre otras. Para Argentina se considera un estudio realizado sobre la opinión de los CEO, de las cien empresas más grandes, referida a la Sustentabilidad y que, desde el ámbito profesional contable, la Federación Argentina de Consejos Profesionales de Ciencias Económicas (FACPCE), aprueba en 2012 la Resolución Técnica (RT) Nº 36: Normas contables profesionales: Balance Social. El Mencionado Balance Social se compone por la memoria de sostenibilidad de la Global Reporting Initiative (GRI) y el Estado de Valor Económico Generado y Distribuido (EVEGyD). En 2015 GRI brinda su más reciente versión G4 que incluye una fe de erratas para corregir algunos problemas terminológicos y ambigüedades textuales, y FACPCE en 2016 aprueba la RT Nº 44, que actualiza la anterior RT Nº 36.In the present study it is recalled that since 2017 the new Directive 2014/95 / EU has to be applied in the European Union, on disclosure of non-financial information and diversity, reports also known as corporate responsibility or sustainability, for organizations with more than 500 employees, recommending international guidelines such as the G4 version of the Global Reporting Initiative (GRI), among others. For Argentina it is considered a study carried out on the opinion of the CEOs, of the hundred largest companies, referred to the Sustainability and that, from the professional accounting scope, the Argentine Federation of Professional Councils of Economic Sciences (FACPCE), approves in 2012 Technical Resolution (RT) No. 36: Professional Accounting Standards: Social Balance. The aforementioned Social Balance is made up of the sustainability report of the Global Reporting Initiative (GRI) and the State of Economic Value Generated and Distributed (EVEGyD). In 2015, GRI provides its most recent G4 version, which includes an erratum to correct some terminological problems and textual ambiguities, and FACPCE in 2016 approves RT No. 44, which updates the previous RT No. 36.Facultad de Ciencias Económica