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Department of Engineering, ICT and Technologies for Energy and Transport Patent Title Method and related system for the conversion of mechanical energy, coming from a turbine-generator set, to electrical energy. Ref. CNR 10253 Assignee(s): CNR CNR Institute: ISSIA Main Inventor: Gianpaolo Vitale Countries: IT, EP, US Priority date: 08/05/2013 Abstract The present invention refers to a Micro Wind Energy Conversion System (μWECS). It allows energy coming from a synchronous generator, supplied by a vertical-axis Darrieus wind turbine, to be injected into the national single-phase low-voltage grid. Among those known from the literature, the simplest architecture has been chosen for the power stage, which implies the best compromise between cost and performance. As the wind speed varies and transfers power to the turbine, the system is able to compute and to reach the angular speed that allows to extract the maximum available power (MPPT, maximum power point tracking). The system has been conceived for performing such task without using mechanical sensors for the measurement of wind speed and angular speed. This implies an increased reliability and a lower cost. Background The device belongs to the class of Micro Wind Energy Conversion System (μWECS), to be connected to the national single-phase low-voltage grid. It covers a power range from 1 kW to 10 kW. Currently, few devices on the market belong to this class and range. Anyway, those devices are derived from systems, whose hardware architecture and control system have been devised for the Photovoltaic segment and, thus, their performance is quite poor. Technology The system tracks the maximum power exploiting a neural network, which operates as a virtual anemometer, and using an electronic circuit that acts as a virtual encoder. Therefore, mechanical sensors are not needed, enabling to achieve a higher reliability and a lower cost. The control logic has been implemented on a FPGA platform. This architecture implies a higher working frequency and the true parallel execution of several tasks. Advantages and Applications The invention solves the problem of dead times in the MPPT transients within μWECS employing permanent magnet synchronous machines, without using mechanical sensors (encoder/anemometer). Therefore, the yielded energy is higher, compared to a traditional system, especially at low wind speed, and an increase of reliability and robustness is obtained. Development stage The invention has already been experimentally tested by building a prototype with rated power of 1 kW. A technology transfer agreement has been signed with a Sicilian consortium for assigning an exclusive license for commercialization; now, it collaborates with CNR ISSIA - UOS of Palermo in building a pre-production 77 prototype.