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This thesis proposes a theoretical and experimental framework for the modeling, analysis and design of a complete energy and data transfer system, which provides constant performances independently of the receiver position. The energy transfer is considered for industrial scenarios, which require high powers and efficiencies, as well as for biomedical implants, which have high distances but do not require necessarily high efficiency. In the former, the method provides a constant received voltage, independent of the load and position in one direction of the receiver and without any feedback loop. It is based on a geometrical optimization of an inductive link composed of three coils and on resonant inverters and rectifier, respectively in class EF and E, operating at 6.78MHz. Furthermore, it enables to passively localize the receiver, without requiring its involvement. In the latter, the proposed solution enables to power small implants without knowing their orientation. The high throughput data transfer is intended for the industrial scenario, where it integrates in a single system with the power link and enables every part to connect and cooperate with each other. It employs consumer hardware and provides bandwidths of over 100Mb/s, independently of the position and with high resistance to interference., Questa tesi propone un quadro teorico e pratico per la modellazione, l'analisi e il progetto di un sistema completo per il trasferimento di energia e dati indipendente dalla posizione del ricevitore. Il trasferimento di energia è trattato sia per scenari industriali, che richiedono alte potenze ed efficienze, sia per quelli di impianti biomedicali, che presentano distanze significative ma non necessitano di particolari efficienze. Nel primo caso, il metodo proposto consente una tensione al ricevitore costante, indipendente dalla posizione, in una direzione, e dal carico del ricevitore, senza nessuna necessità di controllo in retroazione. Si basa sulla ottimizzazione geometrica di un link induttivo composto da tre spire e su inverter e rettificatore risonanti, in classe EF ed E, rispettivamente, funzionanti a 6.78MHz. Consente inoltre di localizzare il ricevitore in maniera passiva e indipendente dal ricevitore. Nel secondo caso, la soluzione proposta consente di alimentare dispositivi impiantabili indipendentemente dalla loro rotazione. Il trasferimento dei dati a banda larga si inserisce nello scenario industriale, integrandosi in un unico sistema di potenza e dati, con la possibilità anche di interagire tra loro. Attraverso l'uso di hardware di consumo, consente bande superiori a 100Mb/s, indipendentemente dalla posizione, con ottima resistenza alle interferenze.

In this paper we describe a geometry design solution to minimize performance variations of a wireless power transfer system “on the move” (WPT-Mob). A sequence of switchable couples of coils, connected in series or in parallel, is adopted at the fixed transmitting link side; the geometry of the moving receiver is optimized to keep the coupling factor, and thus the power transfer, constant during the movement. First the analytical formulation of the link coupling factor is derived as a function of its circuit-equivalent parameters computed by full-wave simulation. Then selected geometry parameters of the receiver side are optimized to keep the coupling factor constant while the link is moving. A set of TX-RX arrangements are simultaneously analysed to emulate the sliding movement of the WPT-Mob. The final optimized geometry demonstrates that a constant power transfer on-the-move is enabled, even for variable TX-to-RX link distances. Design and experimental verification are carried out for a geometry suitable for medium power transfer (tens of Watts) at 6.78 MHz, but the method is formulated in such a way that the system can be scaled up and down to accomplish different application needs.

The idea of this paper is to develop a moving resonant wireless power transfer (WPT) system capable of keeping the coupling factor, and thus the power transfer, invariable with respect to the reciprocal system sides positions. A typical scenario is the WPT to moving objects on a platform equipped with a sequence of coils underneath. If a single TX coil is active at a time, the receiver movement would cause the coupling coefficient, and consequently the transmitted power, to oscillate. To cope with this problem, in this work we propose to make use of two active Tx coils. Different coil geometries and coil connections have been investigated, trying to get an insight into the coupling mechanism. This have been done by full-wave simulations and measurements of the selected structures and by varying some key parameters of the geometry itself. The connections between coils have been done in post-processing and the results have been plotted for comparison. Future work has been proposed.