Modeling and control of a microgrid connected to the INTEC university campus

Producción CientíficaA smart microgrid is a bidirectional electricity generation system—a type of system that is becoming more prevalent in energy production at the distribution level. Usually, these systems have intermittent renewable energy sources, e.g., solar and wind energy. These low voltage networks contribute to decongestion through the efficient use of resources within the microgrid. In this investigation, an energy management strategy and a control scheme for DG units are proposed for DC/AC microgrids. The objective is to implement these strategies in an experimental microgrid that will be developed on the INTEC university campus. After presenting the microgrid topology, the modeling and control of each subsystem and their respective converters are described. All possible operation scenarios, such as islanded or interconnected microgrids, different generation-load possibilities, and state-of-charge conditions of the battery, are verified, and a seamless transition between different operation modes is ensured. The simulation results in Matlab Simulink show how the proposed control system allows transitions between the different scenarios without severe transients in the power transfer between the microgrid and the low voltage network elements.República Dominicana (FONDOCYT Grant 2018-2019-3C1-160 (055-2019 INTEC

Conversión sigma-delta aplicada al control de inversores resonantes; Sigma-Delta Conversion Applied to the Control of the Resonant Inverters

<p>Se realiza un estudio sobre la conversi&oacute;n sigma-delta aplicada al control de inversores de enlace de<br />continua resonantes. Este tipo de configuraci&oacute;n inversora (inversor resonante con enlace CD) es factible<br />de utilizar como parte integrante de un sistema fotovoltaico de energ&iacute;a porque presenta la ventaja de que<br />todos los elementos conmutan a tensi&oacute;n o corriente cero, tanto los elementos de alta frecuencia como los<br />que act&uacute;an de inversor, sin necesidad de modular la tensi&oacute;n de continua, lo cual simplifica considerablemente<br />el lazo de control. La conversi&oacute;n an&aacute;loga digital es una etapa clave en la mayor&iacute;a de los sistemas<br />electr&oacute;nicos modernos. Una vez, en formato digital, las se&ntilde;ales pueden ser f&aacute;cilmente almacenadas y<br />procesadas para obtener la informaci&oacute;n deseada.</p><p>&nbsp;</p><p>&nbsp;</p><p>This paper presents an analysis of the sigma-delta conversion applied to the control of the DC link<br />resonant inverters. This inverter configuration is often employed as a part of photovoltaic system because<br />it presents the advantage that the semiconductors elements commute at zero tension or zero current. It<br />happen on the high frequency elements and the inverter elements, and it is not necessary to modulate the<br />DC tension, condition that simplified the control loop. Conversion analog-digital is an important step of the<br />almost every modern electronics systems. After the signal is translated to the digital format, it can be<br />processed easily in order to obtain the required information.</p

Análisis y modelado del generador de inducción doblemente alimentado. Analysis and Modeling of Doubly Fed Induction Generators.

Uno de los generadores eólicos de velocidad variable más utilizados en la actualidad es el generador de inducción doblemente alimentado (DFIG). En el presente trabajo se presenta un esquema de control del DFIG. El convertidor de potencia del lado de la red es modelado y controlado usando el vector de tensión orientado a los ejes dq, lo que garantiza que con la componente del eje d de la corriente se pueda controlar la potencia activa y, por consiguiente, la tensión del bus DC. La componente del eje q es forzada a cero para mantener un factor de potencia unitario. En el convertidor del lado del rotor se utiliza un control orientado al flujo del estator. Para la sincronización con la red se utiliza un método novedoso basado en el método GDSC-PLL (Generalizad delayed signal cancellation). Además, se presenta un análisis del comportamiento del DFIG, ante huecos de tensión.  One of the variable speed wind turbines most commonly used today is the doubly feed induction generator(DFIG).A control scheme of DFIG is discussed in this paper. The power converter connected to the grid side (bus) is modeled and controlled using voltage vectororiented dq reference frame, whichguarantees that the active power can be controlled by the daxiscurrent component and consequently the DC bus voltage. The qaxis component is forced to be zero in order to ensurethe unitary power factor. Astator flux oriented control in the rotor circuit converter is used.A novel GDSC-PLL method is used in order to achieve an efficient synchronization with the grid.Onthe order hand, this paper presents an analysis about the DFIG (Double Feed Induction Generator) behavior during voltages sags.</p

Modeling and Control of a Microgrid Connected to the INTEC University Campus

A smart microgrid is a bidirectional electricity generation system&mdash;a type of system that is becoming more prevalent in energy production at the distribution level. Usually, these systems have intermittent renewable energy sources, e.g., solar and wind energy. These low voltage networks contribute to decongestion through the efficient use of resources within the microgrid. In this investigation, an energy management strategy and a control scheme for DG units are proposed for DC/AC microgrids. The objective is to implement these strategies in an experimental microgrid that will be developed on the INTEC university campus. After presenting the microgrid topology, the modeling and control of each subsystem and their respective converters are described. All possible operation scenarios, such as islanded or interconnected microgrids, different generation-load possibilities, and state-of-charge conditions of the battery, are verified, and a seamless transition between different operation modes is ensured. The simulation results in Matlab Simulink show how the proposed control system allows transitions between the different scenarios without severe transients in the power transfer between the microgrid and the low voltage network elements