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This project is the continuation of two previous projects carried out by UPC colleagues that studied the insecticidal effect of natural products against aphids and red spider, with the aim of being able to advise efficiently on the use of these products in agricultural areas in process of development, where there's a need to produce natural, effective and cheap insecticides. One of these areas is Cassamance (Senegal, Africa), where UPC has been developing agricultural cooperation projects for years. For this reason, the study has been carried out in conditions as similar as possible to those of Cassamance, using cheap and easily accessible materials with simple application techniques against aphids and red spider, pests with a great degree of affection in the area. The purpose of this project is to study the effectiveness of different natural insecticide products of own elaboration in the control of aphids and red spider in fruit and vegetables, and compare it with the effectiveness of various products used in conventional agriculture. Four natural products were prepared and applied: soap, garlic+soap, onion+soap and neem+soap, and were compared with three conventional products (potassium soap, Oberon and Decis Protech) depending on the pest treated. The insecticide effectiveness of these products has been evaluated in two trials on aphids (Hyalopterus amygdali) on peach trees and one trial on red spider (Tetranychus urticae) on eggplant. The second test against aphids was carried out under laboratory conditions to obtain more accurate results, without the effects of external alterations, so the results could be compared with those of the first test. All natural products produced had, to a greater or lesser extent, an insecticidal effect on populations of aphids and red spiders. In the first trial on aphids in the field, the most effective treatments were garlic+soap and onion+soap, followed by soap. In the second trial against red spider in greenhouse, the most effective treatment was neem+soap. In the third trial against aphids in laboratory conditions, the most effective treatments were soap, garlic+soap and onion+soap, causing a shock effect on the population of aphids in 12 hours. Este proyecto es la continuación de dos trabajos anteriores elaborados por compañeros de la UPC que estudiaban el efecto insecticida de productos naturales contra pulgón y araña roja, con el objetivo de poder asesorar eficazmente en el uso de estos productos en zonas agrícolas en vía de desarrollo, donde hay una necesidad de producir insecticidas naturales, efectivos y baratos. Una de estas zonas es Cassamance (Senegal, África), donde la UPC lleva años desarrollando proyectos de cooperación agrícola. Por estos motivos, el estudio se ha desarrollado en condiciones lo más parecidas posibles a las de Cassamance, usando materiales baratos y de fácil acceso, con técnicas de aplicación simples, contra pulgón y araña roja, plagas con gran grado de afección en la zona. El objetivo de este trabajo es estudiar la eficacia de diferentes productos insecticidas naturales de elaboración propia en el control de pulgón y araña roja, en frutales y hortícolas, comparando con la eficacia de diferentes productos usados en agricultura convencional. Se elaboraron y aplicaron cuatro productos naturales que son jabón, ajo+jabón, cebolla+jabón y neem+jabón y se compararon con tres productos convencionales (jabón potásico, Oberon y Decis Protech) dependiendo de la plaga tratada. Se ha evaluado la eficacia insecticida de estos productos mediante dos ensayos sobre pulgón (Hyalopterus amygdali) en melocotoneros y un ensayo sobre araña roja (Tetranychus urticae) en berenjenas. El segundo ensayo contra pulgón se realizó en condiciones de laboratorio para obtener unos resultados más ajustados, sin efectos de alteraciones externas, y así contrastar los resultados con los del primer ensayo. Todos los productos naturales elaborados tienen un efecto insecticida sobre las poblaciones de pulgón y araña roja, en menor o mayor medida. En el primer ensayo sobre pulgón en campo, los tratamientos más eficaces han sido el de ajo+jabón y cebolla+jabón, seguido de jabón. En el segundo ensayo contra araña roja en invernadero, el tratamiento más eficaz ha sido el de neem+jabón. En el tercer ensayo contra pulgón en laboratorio, los tratamientos más eficaces han sido el de jabón, ajo+jabón y cebolla+jabón, provocando un efecto de choque sobre la población de pulgones a las 12 horas. Aquest projecte és la continuació de dos treballs anteriors elaborats per companys de la UPC que estudiaven l'efecte insecticida de productes naturals contra pugó i aranya roja, amb l'objectiu de poder assessorar eficaçment en l'ús d'aquests productes en zones agrícoles en via de desenvolupament, on hi ha una necessitat de produir insecticides naturals, efectius i barats. Una d'aquestes zones és Cassamance (Senegal, Àfrica), on la UPC porta anys desenvolupant projectes de cooperació agrícola. Per aquests motius, l'estudi s'ha desenvolupat en condicions els més semblants possibles a les de Cassamance, usant materials assequibles i de fàcil accés, amb tècniques d'aplicació simples, contra pugó i aranya roja, plagues amb gran afecció en la zona. L'objectiu d'aquest treball és estudiar l'eficàcia de diferents productes insecticides naturals d'elaboració pròpia en el control de pugó i aranya roja, en fruiteres i hortícoles, comparant amb l'eficàcia de diferents productes usats en agricultura convencional. Es van elaborar i van aplicar quatre productes naturals que són sabó, all+sabó, ceba+sabó i neem+sabó i es van comparar amb tres productes convencionals (sabó potàssic, Oberon i Decis Protech) depenent de la plaga tractada. S'ha avaluat l'eficàcia insecticida d'aquests productes mitjançant dos assajos sobre pugó (Hyalopterus amygdali) en presseguers i un assaig sobre aranya roja (Tetranychus urticae) en albergínies. El segon assaig contra pugó es va realitzar en condicions de laboratori per a obtenir uns resultats més ajustats, sense efectes d'alteracions externes, i així contrastar els resultats amb els del primer assaig. Tots els productes naturals elaborats tenen un efecte insecticida sobre les poblacions de pugó i aranya roja, en menor o major mesura. En el primer assaig sobre pugó en camp, els tractaments més eficaços han estat el d'all+sabó i ceba+sabó, seguit de sabó. En el segon assaig contra aranya roja en hivernacle, el tractament més eficaç ha estat el de neem+sabó. En el tercer assaig contra pugó en laboratori, els tractaments més eficaços han estat el de sabó, all+sabó i ceba+sabó, provocant un efecte de xoc sobre la població de pugons a les 12 hores. Objectius de Desenvolupament Sostenible::1 - Fi de la Pobresa Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables

This paper presents a new calculation method to obtain the reference currents for a selective shunt active power compensator (APC) with the capability of distinguishing between selective and global operating modes. This selective compensation operation is done through an identification of the current terms related to the physical phenomena that exist in electrical systems following a new equivalent conductance concept. Through this identification, this paper proposes the adequate set of reference currents that, used by a shunt APC (SAPC), achieve the selective cancellation of a desired nonefficient phenomenon. Furthermore, by combining the different current terms, it is possible to derive the sets of reference currents that allow the cancellation of a desired combination of nonefficient phenomena. By using these reference currents, a selective compensation feature is added to the SAPC control. An SAPC based on a three-phase three-leg inverter with a split dc bus has been implemented. The neutral wire of the electrical installation is connected to the midpoint of the dc bus, so the selective SAPC is able to work in four-wire electrical systems. The experimental results obtained demonstrate that the proposed selective compensation properly works in three-phase electrical systems with load-current unbalances, voltage asymmetries, and harmonic components. The electric quality is improved with the use of the proposed selective control based on this new equivalent conductance approach.

This paper proposes a method to obtain the reference currents of a shunt active power compensator based on the nonactive power magnitudes defined in IEEE Standard 1459-2000. These reference currents are used to control a shunt active power compensator that features new selective compensating capabilities. Fundamental positive-sequence reactive power, unbalance power, and nonfundamental effective apparent power present in electric systems can be cancelled individually or combined with each other. Experimental results are obtained using a three-branch four-wire shunt active compensator. These results demonstrate that the proposed selective compensator works well in three-phase electrical systems with load currents, including phase shifts, unbalance,s and distortion, and with voltages, including asymmetries and harmonic components. The electric quality is improved with the use of the proposed selective control.

This paper presents the simulated and experimental results of an improved shunt active power compensator (SAPC). The proposed power compensator achieves IEEE Standard 1459 compliance by using moving-window discrete Fourier transform (DFT) calculations to obtain reference currents, and a time-efficient current regulator. The current regulator is based on the analysis of the per-phase electrical model of the (APC). The main feature of the proposed current regulator is the good compromise between current control behavior and time execution efficiency. This compromise results in a low computational cost current regulator with suitable control features, which allows for the implementation of a high-frequency acquisition current control loop, including an extensive computation method based on the use of moving-window DFTs to obtain the proper reference currents with every new sample. The reference current calculations follow the power decomposition proposed by IEEE Standard 1459 for maximum efficiency in supply currents. Simulated and experimental results demonstrate that the proposed SAPC operates correctly under unbalanced and nonsinusoidal conditions. A timing performance comparison is done between the proposed current control and the dq0 technique.