Impacto do Controle de Alinhamento com o Vento na Eficiência de Aerogeradores

Abstract

Wind aligment control systems on wind turbines are mechanisms used to increase the efficiency of those machines. For small wind generator the direction adjust is done just by wind force (passive control). However from a certain size, the wind generators start to use a eletromechanical control system (active control). On this last type, control eletronic systems with eletromechanical actuators can partially replace the wind as a motion agent and execute the task in a continuous and realiable way. The lack in literature of the viable minimum generation power to implementation of active control systems in windgenerators was one of the justifications for accomplishment of this work. Therefore we aim to compare the effect of employment of active (discrete) and passive control systems on a windgenerator model. To compare the systems on essays we built a hibrid direct system and implemented on the small wind turbine. In other words, with little changes of parts, the direction system could be changed from passive to active. Thus the both systems could be tested separately on the same plant increasing the comparison crediblity. To verify the systems’ capability to allign, it was applied the air propulsion by fans in a controlled environment out of wind turbine allignment. Also different wind speeds were applied to verify the impact of those on direction control. Thus effort data, turbine rotation speed, voltage and eletric current on load were collected. The results showed in same wind speeds to both systems and when the difference of power became significant, that the power generation was on average 16,5% greater when using the active system. The model with active direction system showed greater performance than the passive system from speed of 4,9 to 5,3m/s. The greater efficience of the machine is demonstrated with obtained data on graphs and tables. For smaller than 4,9m/s wind speeds, the passive system showed to be superior, but the difference in absolute power values were not expressive as the they were on speeds from 4,9 to 5,3m/s. The worse performance of active system on small velocities is due the smaller area used on the birute of this system. Continuous improvements are being accomplished on model windgenerator that will remain on laboratory so will be possible to obtain more data for other articles and future studies.