Optimal Design of Continuously Variable Power-Split Transmissions for the Wind Energy Conversion System

The aim of this article is to study the possibility of integrating and designing an optimal continuously variable power-split transmission (CVPST) in the drivetrain of a wind system (rotor, gearbox, and generator). The work focused on the research and defining solutions in the preliminary design phase through structural and behavioral analysis of continuously variable power-split transmissions integrated into the driveline of this system. A CVPST is a gearbox whose gear ratio is dynamic; it can be controlled to take any value within its upper and lower limits. Therefore, regulating the rotation frequency of the shaft of the generator via the continuously variable transmission replaces the traditional solution by using the power electronics that connect the generator to the electrical grid. These systems would permit the turbine to operate at its maximum efficiency and the generator to produce power with a regular frequency without using other devices. Previous studies have suggested that continuously variable transmission achieves this purpose using classical or intelligent controllers, such fuzzy logic (FL), artificial neural network (ANN) or a hybrid technique, called adaptive neuro-fuzzy inference system (ANFIS).