Frequency support characteristics of grid-interactive power converters based on the synchronous power controller

Grid-interactive converters with primary frequency control and inertia emulation have emerged and are promising for future renewable generation plants because of the contribution in power system stabilization. This paper gives a synchronous active power control solution for gridinteractive converters , as a way to emulate synchronous generators for inerita characteristics and load sharing. As design considerations, the virtual angle stability and transient response are both analyzed, and the detailed implementation structure is also given without entailing any difficulty in practice. The analytical and experimental validation of frequency support characteristics differentiates the work from other publications on generator emulation control. The 10 kW simulation and experimental frequency sweep tests on a regenerative source test bed present good performance of the proposed control in showing inertia and droop characteristics, as well as the controllable transient response.Peer ReviewedPostprint (author's final draft

Dynamics estimation and generalized tuning of stationary frame current controller for grid-tied power converters

The integration of AC-DC power converters to manage the connection of generation to the grid has increased exponentially over the last years. PV or wind generation plants are one of the main applications showing this trend. High power converters are increasingly installed for integrating the renewables in a larger scale. The control design for these converters becomes more challenging due to the reduced control bandwidth and increased complexity in the grid connection filter. A generalized and optimized control tuning approach for converters becomes more favored. This paper proposes an algorithm for estimating the dynamic performance of the stationary frame current controllers, and based on it a generalized and optimized tuning approach is developed. The experience-based specifications of the tuning inputs are not necessary through the tuning approach. Simulation and experimental results in different scenarios are shown to evaluate the proposal.Peer ReviewedPostprint (published version

Caracterización de un sistema fotovoltaico con convertidor multinivel

Este proyecto se desarrolla en el ambito de las energias renovables y la electrónica de potencia. En concreto, se centra en el estudio de un sistema de generación de energía eléctrica mediante paneles fotovoltaicos que cuenta con un convertidor est atico trabajando como inversor para proporcionar una tensi on alterna trif asica. El convertidor empleado cuenta con una topolog a multinivel y el objetivo principal del estudio es comprobar que este tipo de convertidores permite obtener m as potencia que los tradicionales de dos niveles cuando no todos los paneles trabajan en las mismas condiciones ambientales. A tal n, se lleva a cabo un an alisis del control empleado y se realizan unas simulaciones. Los resultados del an alisis y las simulaciones permiten dise~nar un nuevo esquema de control. Tras las simulaciones se construye un prototipo y se validan los resultados experimentalmente. Los resultados obtenidos en simulaci on dan una ventaja a este tipo de convertidores frente a los tradicionales en un amplio rango de operaci on, una ventaja que se incrementa y extiende a un mayor rango con el nuevo esquema de control dise~nado. Las pruebas experimentales realizadas con rman la tendencia observada en simulaci on y demuestran que en un conjunto amplio de condiciones los convertidores multinivel consiguen extraer m as potencia que los convertidores de dos niveles y que las prestaciones mejoran al emplear el nuevo control

Impact of 100-MW-scale PV plants with synchronous power controllers on power system stability in northern Chile

© 2017, The Institution of Engineering and Technology. The impact that renewable energy sources interfaced by power electronics have on power systems becomes more important as their share in the generation mix increases, thus requiring detailed analyses that take into account their dynamics and controllers. In this study, the impact of photovoltaic (PV) power plants on the power system of northern Chile is analysed. The studied plants employ a controller that allows power converters to interact with the grid like virtual synchronous generators, and their model includes the dynamics of the plant and converter controllers, as well as the dc and PV system. The presented analysis, which comprises modal analysis and time-domain simulations of large disturbances, evaluates the impact of these plants with respect to PV plants based on a conventional converter controller. Tests and validations of the proposed models and controllers are carried out for an actual PV plant connected to the power system of northern Chile, and for a higher PV penetration case. The results show the ability of PV plants formed by virtually synchronous power converters to limit frequency excursions induced by large power imbalances, and to mitigate power oscillations of the synchronous machines in the system.Peer ReviewedPostprint (author's final draft

Adaptive vector control based wave-to-wire model of wave energy converters

This study presents a complete wave-to-wire model in which a novel wave energy converter control approach based on adaptive vector control is introduced. The proposed control for maximum power absorption of the primary resource is included, as well as the grid interconnection topology and required controllers, needed for processing the power over the entire wave energy conversion chain. Thanks to the adaptive performance of the proposed controller, maximum energy extraction can be instantaneously achieved regardless of the current irregular wave characteristics of the resource. Finally, the proposed electrical configuration arises as a suitable grid interconnection solution, as it not only provides maximum power supply from the wave energy resource, but it also contributes towards further reducing its output power oscillations.Peer ReviewedPostprint (author's final draft

Power system stability analysis under increasing penetration of photovoltaic power plants with synchronous power controllers

The utilisation of renewable sources brings many benefits to electric power systems, but also some challenges such as the impact that renewable power plants employing power electronics have on the grid, which is gaining importance as the penetration of this type of generating stations increases, driven by the construction of large wind or solar photovoltaic (PV) power plants. This study analyses the impact of large-scale PV power plants on a transmission grid for different penetration levels. The analysis considers power plants formed by a number of power converters employing synchronous power controllers (SPCs), that allow them to have a harmonious interaction with the grid, and compares their performance with that of conventional power converter controllers, assuming in both cases that the power plants participate in frequency and voltage regulation. The study addresses both the small-signal stability of the system and its response to large disturbances that alter the active power balance and frequency stability. The results of the analysis show that PV power plants using SPCs are able to limit frequency deviations, improve the oscillation damping, and reduce the stress of other generating units, thus having a beneficial impact on the power system.Peer ReviewedPostprint (author's final draft

Frequency support properties of the synchronous power control for grid-connected converters

Grid-connected converters with primary frequency control and inertia emulation have emerged and are promising for future renewable generation plants because of the contribution in power system stabilization. This paper gives a synchronous active power control solution for grid-connected converters. As design considerations, the virtual angle stability and transient response are both analyzed, and the detailed implementation structure is also given without entailing any difficulty in practice. The analysis and validation of frequency support characteristics are particularly addressed. The 10 kW simulation and experimental frequency sweep tests on a regenerative source test bed present good performance of the proposed control in terms of showing inertia and droop characteristics, and the controllable transient response is also demonstrated.Peer ReviewedPostprint (author's final draft

Grid-connected converters with virtual electromechanical characteristics: experimental verification

Grid-connected power converters, which are frequently used to link renewable generation plants with the grid, are required to provide a better functionality for large scale integration of renewables. They are expected to be gridfriendly, or even grid-supportive, instead of simply grid-feeding or grid-demanding. This paper designs a synchronous power controller for grid-connected converters in detail, emulating the electromechanical characteristics of synchronous machines and improving even its actual performance, as it is based on a virtual approach. Based on this design, the grid-interfacing units are capable of showing inertia, damping, and droop characteristics as synchronous machines and presenting thus a grid-supporting behavior. The detailed control design and experimental validation on a 10 kW laboratory setup acts as the main contribution of this paper, compared with the existing studies on generator emulation controls.Peer ReviewedPostprint (author's final draft

Objetivos de desarrollo sostenible y Derechos Humanos: paz, justicia e instituciones sólidas / Derechos Humanos y empresas

Nota previa / Cástor Miguel Díaz Barrado (pp. 7-9). -- Unión Europea: Derechos Humanos y desarrollo sostenible / Araceli Mangas Martín (pp. 13 - 26). -- Paz, seguridad y gobernanza: el ODS 16 y la Agenda 2030 de desarrollo sostenible / José Antonio Sanahuja (pp. 27 - 54). -- La aplicación extraterritorial de los Derechos Humanos por acciones de empresas / Pablo Antonio Fernández Sánchez (pp. 57 - 60). -- Hacia un futuro tratado internacional sobre las empresas y los Derechos Humanos / Eugenia López-Jacoiste (pp. 61 - 73). -- La importancia del enfoque de los Derechos Humanos en los objetivos de desarrollo del sostenible / Diana M. Verdiales López (pp. 75 - 90). -- La perspectiva de género en la resolución de conflictos armados: las mujeres como agentes de paz / Cristina del Prado Higuera (pp. 93 - 106). -- La mutilación genital femenina desde una perspectiva integral y multidisciplinar / Cristina Hermida del Llano (pp. 107 - 120). -- Poner fin al maltrato, la explotación, la trata y todas las formas de violencia y tortura contra los niños: la trata de niños / María Ángeles Cano Linares (pp. 123 - 136). -- Participación juvenil en el fortalecimiento de las instituciones y el establecimiento de la paz: programas de participación juvenil del sistema de Naciones Unidas / Enrique Hernández Díez (pp. 137 - 160). -- Estado de la violencia criminal en la sociedad internacional: respuestas de la comunidad internacional para avanzar hacia el objetivo 16, Agenda 2030 / Sagrario Morán Blanco (pp. 163 - 178). -- Fortalecer la recuperación y devolución de bienes robados: justicia y reparación del daño causado a las víctimas y la sociedad como metas del objetivo 16 de los objetivos de desarrollo sostenible / Francisco Jiménez García (pp. 179 - 192). -- El derecho internacional, los ODS y la lucha contra el crimen transnacional / Juan Manuel Rodríguez Barrigón (pp. 193 - 216). -- El derecho internacional frente a la criminalidad financiera transnacional: la prevención y sanción del blanqueo de capitales / Jorge Urbaneja Cillán (pp. 217 - 232). -- Acceso a la justicia y objetivos del desarrollo sostenible / Florabel Quispe Remón (pp. 235 - 248). -- Paz y objetivos de desarrollo sostenible: la contribución del objetivo 16 / Elena C. Díaz Galán (pp. 249 - 262). -- Seguridad sanitaria y empresas / Ana Cristina Gallego Hernández (pp. 265 - 272). -- El acaparamiento de tierras por empresas multinacionales y la seguridad alimentaria / Adriana Fillol Mazo (pp. 273 - 288). -- Importancia y características de los planes nacionales de empresas y Derechos Humanos en relación con el desarrollo sostenible / Alberto Jiménez-Piernas García (pp. 289 - 301). -- Objetivo de desarrollo sostenible 16. Principios rectores y espacio iberoamericano: el caso Berta Cáceres / Ana Manero Salvador (pp. 305 - 315). -- Derechos de los pueblos indígenas: marcos de protección en la Agenda 2030 y en los principios rectores sobre empresas y Derechos Humanos / Juan Daniel Oliva Martínez y Adriana Sánchez Lizama (pp. 317 - 331