PROPUESTA DE UN SISTEMA DE CONTROL PARA UN CONVERTIDOR BIDIRECCIONAL CD-CA EMPLEADO PARA TRANSFERIR ENERGÍA ENTRE UN SISTEMA FOTOVOLTAICO Y LA RED ELÉCTRICA DE CORRIENTE ALTERNA (PROPOSAL FOR A CONTROL SYSTEM FOR AN EMPLOYED CD-CA BIDIRECTIONAL CONVERTER TO TRANSFER ENERGY BETWEEN A PHOTOVOLTAIC SYSTEM AND THE ALTERNATE CURRENT ELECTRICAL NETWORK)

ResumenUno de los principales retos en las Micro-Redes de Corriente Directa (µR-CDs) es el diseño e implementación de los sistemas de control encargados de la manipulación de los convertidores electrónicos de potencia. En este trabajo se presenta una propuesta para el diseño e implementación de un sistema de control embebido capaz de manipular la transferencia de energía entre un sistema fotovoltaico y la red eléctrica principal de corriente alterna. Este sistema de control se aplica sobre el convertidor bidireccional CD-CA que forma parte de un prototipo experimental de una µR-CD conformada por un par de Arreglos Fotovoltaicos (AFs) de 500W cada uno, interconexión a la Red Eléctrica Principal (REP) de Corriente Alterna (CA) con una capacidad de 1kW y cargas de CD y CA (cargas resistivas y cargas no lineales como luminarias LED, luminarias fluorescentes y equipo de cómputo) que trabajara en corriente directa.Palabra(s) Clave: Convertidor electrónico de potencia, corriente alterna, corriente directa, micro-red, transferencia de energía. AbstractA main concern in DC Micro-Grids (µR-CDs) is the design and implementation of control systems which are in charge of manipulation of power converters. In this paper, an embedded control system design and implementation is proposed in order to transfer energy from a photovoltaic system to the main grid. This control system is applied over a bidirectional DC-AC converter which is part of a µR-CD comprised by two 500 W PV arrays (AFs), a 1 kW point of common coupling (REP) with the AC main grid, as well as AC and DC loads (resistive and non-linear loads such as LED and fluorescent lamps and computer equipment) which operates in DC.Keywords: AC, DC, power converters, transfer energy

Understanding the impact of depressive symptoms in older-adults functionality Comprendiendo el impacto de los síntomas depresivos en la funcionalidad de las personas mayores

Introduction: Depression is the health conditions that generate a higher disease burden, where the older adults show a great impact related to this disease. The article describes the impact of depressive symptoms in the functional performance of older adults and seeks to understand the existing relationship between functional impairment and depressive symptoms. Method: a literature review was conducted of articles published between years 1990 to 2016. A narrative analysis was conducted with the finding literature. 40 articles were included. Results: One of the main repercussions is the functional impairment and the reduction in the daily life activities participation, related to a progressive dependency, higher fall risk and fear to falls, restriction and reduction of participation in meaningful activities, and worst rehabilitation and health care outcomes. Considering these elements, it is necessary to understand depressive symptoms in older adults in conjunction with functional impa