Construction Of A Low Cost Wind Turbine For Rural Areas in Paraguay
by Raúl Vázquez, Paraguay (PPRE2015-17)
My team and I carried out the project in the Automation and Control Innovation Center - CIAC - of the Itaipu Technology Park Paraguay (where I work), with the objective of building and monitoring a prototype of a low-cost wind generator to be used in rural areas, using as a reference one of the models proposed by Hugh Piggott. It was adapted according to the materials and components available in the region, with the purpose of carrying out theoretical courses or technical workshops with didactic purposes to be offered to all those interested in learning the operating principles of a small wind turbine (or micro wind turbine) and its construction process.
The construction of the wind turbine was carried out completely by hand and consisted of the following: wooden blade (hand-carving), stator (hand winding) and magnet rotor construction, structure development and assembly the components. Both the stator and the magnet rotor are covered with polyester resin to add structural strength and weather resistance. The windings were oversized in order to compensate for any loss due to imperfections and thus achieving an adequate voltage output to be used with a voltage regulator and charge a 12 V battery.
Extensive tests and calibrations, both electrical and mechanical, were carried out; the DC voltage measured at the output of the rectifier gave an average value between 12 V and 15 V, these values are within the expected voltage range and it is suitable for the charge regulator of the battery to supply a continuous and safe voltage during the charging process.
The aerodynamic tests were carried out on the shores of the Itaipu Lake in Hernandarias, where winds greater than 5 m / s were recorded. The wind turbine needs an average of 3.5 m / s to start rotating and the design supports up to approximately 10 m / s (where it reaches the maximum output power), at higher speeds, the tail of the wind turbine will fold itself and adopt a “flag position”, positioning the rotor parallel to the wind direction and thus preventing it from turning, to avoid dangerous overspeed.
This initiative contains an element of knowledge transfer, since it will take advantage of the skills acquired by CIAC technicians to carry out workshops and technical training aimed at students of universities, technicians and the general public. In this way, it is intended to disseminate the importance and understanding of the various techniques used to generate energy in a clean and renewable manner, such as the use of wind energy.