Producción de H2 Basada en GDR y Asistida por Red Débil. Topología, Operación y Control del Sistema

Renewable Distributed Generation (RDG), as a production of electrical power near to the load, is particularly beneficial when the grid is “weak” compared to specific demands, as in the case of hydrogen production systems connected to rural electrification networks. In this situation, the wind resource may be suitable for this type of generation.This paper proposes the topology, operation strategy and control for a hydrogen production station, “assisted” by a weak AC network and “fed” by a variable speed wind turbine based on a three-phase induction machine with double stator. The wind energy conversion is optimized by proper control of the generator, the electrolyser current is regulated to take maximum advantage of the generated power, the rapid fluctuations in power, due to turbulences, are compensated by a controlled energy storage system with flywheel.System configuration, mode of operation and control, and validation by simulation are presentedLa Generación Distribuida Renovable (GDR), como producción de energía eléctrica en proximidades de la carga, resulta particularmente beneficiosa cuando la red de distribución es “débil” frente a demandas puntuales, como sucede en los sistemas de producción de hidrógeno conectados a redes de electrificación rural. En este ámbito, el recurso eólico puede ser adecuado para este tipo de generación. En el trabajo se propone la topología y la estrategia de operación y control para una estación de producción de hidrógeno, “asistida” por una red débil de CA y “alimentada” por un aerogenerador de velocidad variable, basado en una máquina de inducción trifásica de doble estator. La conversión eólica es optimizada mediante un adecuado control del generador; la corriente del electrolizador es regulada para el máximo aprovechamiento de la potencia generada; las fluctuaciones rápidas de potencia, por turbulencias, son compensadas mediante un sistema controlado de almacenamiento de energía con volante de inercia. Se presenta la configuración del sistema, su modo de operación y control, y la validación por simulació

Linear Frequency Domain Method for Load Control by Fluidic Actuation

Simulations of periodic fluidic excitations in the context of active flow control are per- formed using a frequency domain solver for the efficient prediction of global air loads. Frequency domain methods have become a viable choice whenever the disturbance of the flow is small and periodic, and can reduce the computational effort substantially in compar- ison to time-accurate unsteady simulations. Although time-accurate unsteady simulations resolve the entire spectrum of the flow, they suffer from a long transient phase and thus require an extensive use of computational resources. The goal is to extend the time- linearized frequency domain method of the DLR TAU-code toward load control by blowing fluidic actuators. This paper presents the set of discretized unsteady equations and as- sociated boundary conditions for both the time accurate and frequency domain method. The applied time-linearized frequency method decouples each harmonic, forming a linear approach, which renders the sequential calculation of the individual harmonics to evaluate the time response of air loads. At first, blowing actuation for a two-dimensional airfoil with a single slot is considered for which constant as well as periodic excitations are used for validation and investigation purposes of air loads between the time-accurate and nonlinear frequency domain method. In addition, a 2-element high-lift wing with a flow separation on the trailing edge flap is simulated that demonstrates the good prediction quality of air load derivatives with the frequency domain method

Light electric vehicle enabled by smart systems integration

For the first time in history, the majority of people live now in urban areas. What is more, in the next four decades, the number of people living in the world's urban areas is expected to grow from 3.5 billion to 5.2 billion. At the same time, populations around the world are rapidly ageing. By 2050, the global population of people aged 60 years and over is expected to reach almost 2 billion, with the proportion of older people doubling between 2006 and 2050. This growth and ageing of the population will pose great challenges for urban mobility, which will be addressed within the SilverStream project. In particular, it will develop and demonstrate a radically new light and affordable Light Electric Vehicle concept for the ageing population in congested European cities with scarce parking space