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In this paper, a new power control system for wind turbines based on a squirrel cage induction generator linked to the mains by means of a back-to-back converter for smart grid applications is proposed. The wireless system employs orthogonal frequency division multiplexing, convolutional coding, and functionally weighted moving average filtering to improve the system performance against the errors due to the propagation channel in the transmitted power references. Hence, the system avoids damages in turbines and converters and also increases the power quality of the power injected into the grid. Hence, the reactive power injection can be helpful in ancillary services. The system was analyzed regarding the total harmonic distortion for SCIGs' currents and the system response to verifying the delivered power quality by the generator to the mains. The simulated results validate the proposed wireless-coded control system. [ABSTRACT FROM AUTHOR]

Smart grids treat energy in a much more efficient manner than it is done currently by conventional power systems. One important aspect in the design and analysis of smart grids is to take into account some real characteristics of the power system and its loads. In this context, we propose a dynamic load model for residential applications based on a non-homogeneous Poisson process, whose parameters depend on the electrical characteristics of the loads and their time-varying power profiles. Some of the advantages of this model are its flexibility to represent any specific energetic scenario found in different regions of the globe and the possibility to independently control individual low-voltage loads of the evaluated system by modifying the activation function of the corresponding load model. This last characteristic is fundamental to represent adequately and analyze the behavior of smart grids. To demonstrate the accuracy and effectiveness of the proposed strategy, several load curves were generated with the aid of the proposed model and compared against real measurements. [ABSTRACT FROM AUTHOR]

In recent years, wind plants have undergone major changes due to new technologies developed for smart grids (SG). For its success, it becomes necessary the use of modern information and telecommunication infrastructure with bidirectional data flow. In Brazil, due to the high penetration of data networks based on GSM technology (Global System Mobile), such as GPRS (General Packet Radio Service) and EGPRS (Enhanced GPRS), it has attracted the interest of energy companies to carry out the tasks of measurement, monitoring, and control in SG. The use of cellular technology enables at first a significant reduction in the SG deployment costs while providing reliability and security of the information. In this context, the use of a cellular network for monitoring and control data sharing in intelligent wind farms has recently aroused great interest. This work proposes the analysis of a wireless control system based on GPRS and EGPRS data services for variable-speed squirrel-cage induction generators (SCIG) connected to the power grid. The wireless communication system is employed to send the reference power signals to the SCIG controller with the necessary reliability to ensure the power quality provided by the wind turbine. The performance of the proposed system is evaluated by several simulations and tests. [ABSTRACT FROM AUTHOR]

The wind energy generation is the huge driver behind the push for supergrids and cross-border infrastructure for renewable energy systems into smart grids. To provide balance supply, demand, and storage of energy over a region in a much more efficient manner than it is done today, smart grids will need to use an advanced communication infrastructure into a robust control system. Towards this objective, this work proposes a wireless coded orthogonal frequency division multiplexing neuro-fuzzy power control employing low density parity-check coding for a doubly fed induction aerogenerator to improve system robustness and reliability. The performance improvements of the proposed system are investigated in a more realistic frequency selective fading propagation condition. [ABSTRACT FROM AUTHOR]