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The growing worldwide energy demand requires the design and construction of increasingly efficient generation systems. In satisfying this need, control schemes play an essential role. Having a system that allows experimental evaluation of their performance is key. In the case of wind energy, one possible control strategy is pitch regulation, which is used in variable pitch wind turbine systems. This paper presents the results of the design and construction of a testing bench for carrying out the experimental evaluation of control strategies for pitch regulated small wind turbines. Rotor operation and pitch regulation were ascertained through wind tunnel testing. Rotors start moving with winds of 3.5 m/s. PI and fuzzy controllers were implemented and tested. [ABSTRACT FROM AUTHOR]

In Cuba, one of the prioritized regions in terms of water erosion is "Cuyaguateje" river basin, where more than 85% of its soil shows a high erosion risk subjected to intensive farming practices. High pluviometric values registered together with the non-uniform topography necessitate spatially characterised rain erosivity in this area, as it constitutes an essential factor of soil erosion. The objectives of this paper were: (a) to compare expressions that predict kinetic energy from rainfall intensity in our basin of interest, (b) to develop and validate the relationship between cumulative rainfall and R factor from RUSLE (Revised Universal Soil Loss Equation) (EI30), (c) to compare results and trends between R and the Modified Fournier Index MFI, as well as with Lal's index AIm (EI7.5), (d) to present rainfall erosivity maps, according to each index calculated. Data from two pluviographic stations were used to calculate R (by Brown and Foster's also Kinnell's kinetic energy equations) and AIm, besides data from 26 pluviometric stations located along the basin of interest. Thus, R values ranged between 8284 and 22044 MJ mm ha-1 h-1yr-1 through both kinetic energy equations, with the highest erosivity values at the top or mountainous part and the lowest values at the basin bottom. Around 96% of the basin area is affected by rainfall with high erosive potential. Correlations between R factor from RUSLE and the other indexes calculated (MFI and AIm) were higher than 0,9. [ABSTRACT FROM AUTHOR]