142 research outputs found
Photovoltaic and Wind Energy Conversion Systems
In the first decades of the current millennium, the contribution of photovoltaic and wind energy systems to power generation capacity has grown extraordinarily all around the world; in some countries, these systems have become two of the most relevant sources to meet the needs of energy supply. This Special Issue deals with all aspects of the development, implementation, and exploitation of systems and installations that operate with both sources of energy
Marine Predator Algorithm (MPA)-Based MPPT Technique for Solar PV Systems under Partial Shading Conditions
To satisfy global electrical energy requirements, photovoltaic (PV) energy is a promising source that can be obtained from the available alternative sources, but partial shading conditions (PSCs), which trap the local maxima power point instead of the global maxima peak power point (GMPP), are a major problem that needs to be addressed in PV systems to achieve the uninterruptable continuous power supply desired by consumers. To avoid these difficulties, a marine predator algorithm (MPA), which is a bio-inspired meta-heuristic algorithm, is applied in this work. The work is validated and executed using MATLAB/Simulink software along with hardware experimentation. The superiority of the proposed MPA method is validated using four different PSCs on the PV system, and their characteristics are compared to those of existing algorithms. The four different PSC outcomes in terms of GMPP are case 1 at 0.07 s 995.0 Watts; case 2 at 0.06 s 674.5 Watts; case 3 at 0.04 s 654.1 Watts; and case 4 at 0.04 s 364.2 Watts. The software- and hardware-validated results of the proposed MPA method show its supremacy in terms of convergence time, efficiency, accuracy, and extracted power.publishedVersio
A novel mppt technique based on mutual coordination between two pv modules/arrays
A novel maximum power point tracking (MPPT) technique based on mutual coordination of two photovoltaic (PV) modules/arrays has been proposed for distributed PV (DPV) systems. The proposed technique works in two stages. Under non-mismatch conditions between PV modules/arrays, superior performance stage 1 is active, which rectifies the issues inherited by the perturb and observe (P&O) MPPT. In this stage, the technique revolves around the perturb and observe (P&O) algorithm containing an intelligent mechanism of leader and follower between two arrays. In shading conditions, stage 2 is on, and it works like conventional P&O. Graphical analysis of the proposed technique has been presented under different weather conditions. Simulations of different algorithms have been performed in Matlab/Simulink. Simulation results of the proposed technique compliment the graphical analysis and show a superior performance and a fast response as compared to others, thus increasing the efficiency of distributed PV systems
Modeling and control of stand-alone AC microgrids: centralized and distributed storage, energy management and distributed photovoltaic and wind generation
El aumento de la penetración de energías renovables en la red eléctrica es necesario
para el desarrollo de un sistema sostenible. Para hacerlo posible técnicamente, se ha
planteado el uso de microrredes, definidas como una combinación de cargas,
generadores distribuidos y elementos de almacenamiento controlados gracias a una
estrategia global de gestión energética. Además, las microrredes aumentan la fiabilidad
del sistema puesto que pueden funcionar en modo aislado en caso de fallo de red.
Esta tesis se centra en el desarrollo de microrredes AC en funcionamiento aislado. El
objetivo principal es el diseño y la implementación de estrategias de gestión energéticas
sin utilizar cables de comunicación entre los distintos elementos, lo que permite reducir
los costes del sistema y aumentar su fiabilidad. Para ello, se abordan los siguientes
aspectos:
• Gestión energética de una microrred AC con generador diesel, almacenamiento
centralizado y generación renovable distribuida
• Diseño de técnicas de control “droop” para repartir la corriente entre inversores
conectados en paralelo
• Gestión energética de una microrred AC con almacenamiento distribuido y
generación renovable distribuida
• Control de la etapa DC/DC de inversores fotovoltaicos con pequeño condensador
de entrada en el seno de una microrred
• Control de extracción de máxima potencia sin sensores mecánicos para sistemas
minieólicos en el seno de una microrred.The introduction of distributed renewable generators into the electrical grid is
required for a sustainable system. In order to increase the penetration of renewable
energies, microgrids are usually proposed as one of the most promising technologies. A
microgrid is a combination of loads, distributed generators and storage elements which
behaves as a single controllable unit for the grid operator. Furthermore, microgrids
make it possible to improve the system reliability because they are capable of standalone
operation in case of grid failure.
This thesis is focused on the development of AC microgrids under stand-alone
operation. Its main objective is to design and implement overall control strategies which
do not require the use of communication cables, thereby reducing costs and improving
reliability. For this purpose, the following aspects are tackled:
• Energy management of an AC microgrid with diesel generator, centralized
storage and distributed renewable generation
• Design of droop methods so that the current is shared among parallel-connected
inverters
• Energy management of an AC microgrid with distributed storage and distributed
renewable generation
• Control of the DC/DC stage in photovoltaic inverters with small input capacitors
within a microgrid
• Sensorless MPPT control for small wind turbines within a microgrid.Programa Oficial de Doctorado en Energías Renovables (RD 1393/2007)Energia Berriztagarrietako Doktoretza Programa Ofiziala (ED 1393/2007
GWO-super-twisting integral sliding mode control of 60 KW PV system based on interleaved boost converter
The energy provided by the PV system is strongly influenced by climatic conditions such as solar radiation and cell temperature. A suitable DC /DC converter and a robust control strategy combined with the maximum power point tracking (MPPT) algorithm are required to harness the maximum power of the panel. This paper proposes a super-twisting integral sliding mode control (ST-ISMC) for four legs interleaved boost converter (FLIBC) as an interface to the MPPT algorithm for a 60 KW PV system. The FLIBC has been used to overcome the drawbacks of the conventional boost converter (CBC). The ST-ISMC is proposed to maintain the PV voltage track the reference provided by the MPPT algorithm and ensure the equal sharing of input current between legs. The controller gains of the proposed ST-ISMC have been calculated using the grey wolf optimization algorithm for better performance. The simulation results prove the excellent performance of the proposed controller over the conventional controller
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