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The holistic objective of producing 100% renewable generated electricity motivates the development of low-power and efficient domestic wind turbines. The wind turbine’s efficiency can be maximized by operating it in a variable speed configuration, thus harvesting all the wind power. However, the harvesting process requires a two-stage conversion from AC to DC and from DC–DC or DC–AC. The paper aims to analyze the performance of the first stage of AC–DC rectification in terms of output voltage ripple and voltage regulation when the loading conditions vary abruptly. In addition, this work investigates the basic uncontrolled and controlled rectification methods for low-power wind turbines. The role of the output capacitance and its effect on output voltage ripples is illustrated. Finally, the paper highlights the design of a three-phase controlled rectifier using a simple yet effective firing angle control of a silicon-controlled rectifier (SCR) device. The delay caused due to the firing angle variations is reported in the simulations and experimental results to support the conclusion drawn from this study.

[EN] In a previous paper the authors compared the AC-AC converters, useful for the frequency regulation in hydroelectric microplants varying the power dissipated in ballasts loads, with the new proposal consisting in a bridge three-phase rectifier using diodes with a serial switch with the load that is switched with symmetric angle. The paper showed that the aforementioned rectifier accomplishes to improve the power factor at the generator output, except for low power consumed by users, near to its minimal value. A way to solve this problem consists in to use three bridge single-phase rectifier using diodes with a serial switch with the load that is switched with symmetric angle. As a consequence, the objective of this article is to carry out a comparison between the aforementioned single-phase rectifier and the AC-AC converter, regarding the power factor at the output of the electric generator of hydroelectric micro-plants that regulate frequency by means of the ballast-load method. [ES] En un trabajo anterior se compararon los convertidores de corriente alterna/corriente alterna (AC-AC), típicamente utilizados para la regulación de frecuencia en microcentrales hidroeléctricas variando la potencia disipada en cargas lastres, con un rectificador trifásico a diodos tipo puente con un interruptor, en serie con la carga, conmutado con ángulo simétrico. En el mismo, se demostró que, con dicho rectificador, se logra mejorar el factor de potencia a la salida del generador eléctrico, excepto para potencias consumidas por los usuarios cercanas a su valor mínimo. Una vía para solucionar este problema consiste en emplear una terna de rectificadores monofásicos a diodos tipo puente con un interruptor, en serie con la carga, conmutado con ángulo simétrico. Así, el objetivo del presente artículo es comparar al rectificador monofásico mencionado y el convertidor de AC-AC, esquema empleado actualmente, respecto a parámetros de interés como es el factor de potencia a la salida del generador eléctrico de las microcentrales hidroeléctricas que regulan frecuencia por el método de carga lastre.

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Micro-size hydro power plants (µHPPs) are commonly used at remote areas to supply islanded AC microgrids. A typical way to control grid frequency is to manipulate active power dissipated in ballast loads by AC/AC converters. However, these asymmetrically switched thyristor controlled converters consume reactive power degrading the power factor at the generator output. In this paper the operation of a symmetric angle switched, bridged three-phase rectifier and three single-phase rectifiers connected in series with ballast load, are studied to improve the power factor of the system. As a consequence, the objective is to evaluated the use of the three and single-phase rectifiers switched with symmetrical angle to improve the power factor, by reactive power compensation, at the output terminal of the electric generator of µHPPs that use ballast load to regulate frequency.

Micro-size hydro power plants (µHPPs) are commonly used at remote areas to supply islanded AC micro-grids. A typical way to control grid frequency is to manipulate active power dissipated in ballast loads by AC/AC converters. However, these asymmetrically switched thyristor controlled converters consume reactive power degrading the power factor at the generator output. In this paper the operation of a symmetric angle switched, bridged three-phase rectifier and three single-phase rectifiers connected in series with ballast load, are studied to improve the power factor of the system. As a consequence, the objective is to evaluated the use of the three and single-phase rectifiers switched with symmetrical angle to improve the power factor, by reactive power compensation, at the output terminal of the electric generator of µHPPs that use ballast load to regulate frequency.

Micro-size hydro power plants are commonly used at remote areas to supply islanded AC microgrids. A typical way to control grid frequency is to manipulate active power dissipated in ballast loads by AC/AC converters. However, these asymmetrically switched thyristor controlled converters consume reactive power degrading the power factor at the generator output. In this paper the operation of a symmetric angle switched, bridged three-phase rectifier and three single-phase rectifiers connected in series with ballast load, are studied to improve the power factor of the system. As a consequence, the objective is to evaluated the use of the three and single-phase rectifiers switched with symmetrical angle to improve the power factor, by reactive power compensation, at the output terminal of the electric generator of µHPPs that use ballast load to regulate frequency.

Micro-size hydro power plants are commonly used at remote areas to supply islanded AC micro-grids. A typical way to control grid frequency is to manipulate active power dissipated in ballast loads by AC/AC converters. However, these asymmetrically switched thyristor controlled converters consume reactive power degrading the power factor at the generator output. In this paper the operation of a symmetric angle switched, bridged three-phase rectifier and three single-phase rectifiers connected in series with ballast load, are studied to improve the power factor of the system. As a consequence, the objective is to evaluated the use of the three and single-phase rectifiers switched with symmetrical angle to improve the power factor, by reactive power compensation, at the output terminal of the electric generator of µHPPs that use ballast load to regulate frequency.

[EN] In a previous paper the authors compared the AC-AC converters, useful for the frequency regulation in hydroelectric microplants varying the power dissipated in ballasts loads, with the new proposal consisting in a bridge three-phase rectifier using diodes with a serial switch with the load that is switched with symmetric angle. The paper showed that the aforementioned rectifier accomplishes to improve the power factor at the generator output, except for low power consumed by users, near to its minimal value. A way to solve this problem consists in to use three bridge single-phase rectifier using diodes with a serial switch with the load that is switched with symmetric angle. As a consequence, the objective of this article is to carry out a comparison between the aforementioned single-phase rectifier and the AC-AC converter, regarding the power factor at the output of the electric generator of hydroelectric micro-plants that regulate frequency by means of the ballast-load method., [ES] En un trabajo anterior se compararon los convertidores de corriente alterna/corriente alterna (AC-AC), típicamente utilizados para la regulación de frecuencia en microcentrales hidroeléctricas variando la potencia disipada en cargas lastres, con un rectificador trifásico a diodos tipo puente con un interruptor, en serie con la carga, conmutado con ángulo simétrico. En el mismo, se demostró que, con dicho rectificador, se logra mejorar el factor de potencia a la salida del generador eléctrico, excepto para potencias consumidas por los usuarios cercanas a su valor mínimo. Una vía para solucionar este problema consiste en emplear una terna de rectificadores monofásicos a diodos tipo puente con un interruptor, en serie con la carga, conmutado con ángulo simétrico. Así, el objetivo del presente artículo es comparar al rectificador monofásico mencionado y el convertidor de AC-AC, esquema empleado actualmente, respecto a parámetros de interés como es el factor de potencia a la salida del generador eléctrico de las microcentrales hidroeléctricas que regulan frecuencia por el método de carga lastre.

Este trabajo muestra la implementación de controladores no convencionales (Resonadores, Repetitivos, y GPI), para la corrección dinámica del factor de potencia en rectificadores monofásicos y trifásicos conmutados, dichas implementaciones permiten aumentar el desempeño en variables como factor de potencia y THD, aumentando de esta manera la calidad de la energía que estos dispositivos utilizan de la redes eléctricas. Rechazando las perturbaciones inherentes en este sistema como presencia de armónicos, desbalances, SAC, y cambios de carga. Abstract. This work shows the implementation of unconventional controllers (Resonators, repetitive, and GPI), for dynamic power factor correction switched in single and three phase rectifiers, these implementations allow increased performance variables such as power factor and THD, increasing Thus the quality of these devices utilize energy of power grids. Rejecting disturbances inherent in this system as the presence of harmonics, imbalances, SAC, and load changes. Maestría

[ES] Muchas de las microcentrales hidroeléctricas, útiles por la producción de electricidad en regiones de difícil acceso, operan en régimen autónomo, por lo que es necesario realizar la regulación de frecuencia de la tensión generada. Una vía de regular frecuencia es variando la potencia disipada en cargas balastros mediante convertidores AC-AC. Estos convertidores consumen potencia reactiva, empeorando el factor de potencia a la salida del generador. Sin embargo, una alternativa para evitar el empeoramiento del factor de potencia, es el empleo de un rectificador trifásico a diodos tipo puente con interruptor, en serie con la carga, conmutado con ángulo simétrico. El objetivo del presente artículo es comparar dicho rectificador mencionado y el convertidor de AC-AC, esquema más empleado actualmente, respecto a parámetros de interés como es el factor de potencia a la salida del generador eléctrico de las microcentrales hidroeléctricas que regulan frecuencia por el método de carga lastre., [EN] Many of hydroelectric micro-plants, useful for the electricity production at intricate regions, operate in autonomous regimen. Therefore, it is necessary to accomplish the control of frequency. One way to control the frequency is varying the power dissipated in ballast loads employing AC-AC converters. These converters consume reactive power, contributing to aggravate the power factor at the generator output. An alternative in order to avoid the deterioration of the power factor is the use of a bridge three-phase rectifier using diodes with a serial switch with the load that is switched with symmetric angle. As a consequence, the objective of this article is to carry out a comparison between the aforementioned three-phase rectifier and the AC-AC converter, regarding the power factor at the output of the electric generator of hydroelectric micro-plants that regulate frequency by means of the ballast-load method.