Abstract

Airborne wind energy (AWE) systems possess theoretically a strong potential as an efficient cost-effective replacement for conventional wind turbines (CWTs). However, several highly correlated design, operational and engineering aspects; hinder the commercialization of such technology. One of those challenges, from an electrical perspective, is the selection of an efficient fault-tolerant electrical drive. The ongoing trend of employing three-phase drives as those for CWTs is non-optimal; since statistics revealed that failure rates of power electronic converters, their connections to the machine terminal and stator windings represent the highest failure rates among the CWT components. When safety measures are embraced, the faulty part is disconnected leading to a single phase operation, which jeopardizes the airborne membrane and eventually a complete failure of the AWE system. A suitable alternative is power-segmentation of the machine by rewinding to a dual three-phase (DT) machine, ensuring reliable continuous operation owing to their inherent fault-tolerant capability. This thesis proposes the utilization of DT interior permanent magnet synchronous machines. Compared to the available body of literature, the main contributions of the carried-out work are: (i) identifying the machine non-linearities; (ii) modeling and simulating the machine dynamics; (iii) efficient operation coupled with a zero steady-state error current regulator; and (iv) deriving a post-fault optimization without exceeding the machine ratings (i.e. currents and voltages). Experimental results are provided for the sake of validation.