Freio de Foucault Aplicado à Medição de Potência em Turbina Eólica Savonius / Eddy Brake Applied to Power Measurement in Wind Turbine Savonius

Charles Rech, Andre Francisco Caldeira, Cristiano Frandalozo Maidana, Carlos Eduardo de Souza, Greice Scherer Ritter, Pericles Nicolau Balafa, Simone Ferigolo Venturini


In this work is proposed the design of a dynamometer based on Foucault's Current Break for the evaluation of torque and power provided by a Savonius wind turbine model in a wind tunnel. The applied measurement system is of the open source type using the Arduino platform. For the reaction force metering a load cell with converter and amplifier H711 was used as well as a photoelectric sensor with resolution of one pulse per turn for the rotation measurement. Equations available in the literature were used to estimate the wind turbine performance parameters for the dynamometer sizing. The wire applied for magnetic flux generation in the coils is AWG24, to support an electrical current rating of 0.5 A and a voltage of 1.0 V. The coils size are 3.1 cm of diameter and 3.0 cm of length. Two coils were applied in order to satisfy the wind turbine demand. As a result, the dimensional characteristics of an eddy current brake able to measure a power of up to 0.5 W, generated by a Savonius wind turbine, were obtained, with uncertainty of measurement about 0.01 W, being adequate for the analyzed turbine.



Savonius turbine, Foucault dynamometer, wind tunnel, torque and power measurement, instrumentation.


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