1 |
Optimization of Near Field Coupling for Efficient Power Transfer Utilizing Multiple Coupling StructuresWilliams, Devin Wells 23 June 2011 (has links)
A rise in the need for dynamic energy allocation has been associated with the saturation of available portable wireless electronic devices. Currently, the methods for transmitting this energy efficiently have been limited to a number of options, including near field resonant magnetic coupling. Previous research with mid-range (dâ 4r) wireless power transfer has resulted in coupling efficiencies of close to 40%. In order to increase efficiency in transfer a more directive transmission system was developed using a phased array. Coupling networks were used to shift the resonance of the coupling device, leading to a tightly coupled network by array phasing. Coupling networks for the phased array were optimized using a hybrid combination of a full wave Method of Moments simulation with circuit simulation. Results were validated in a full wave simulator, and field results were shown during resonance. S-parameter results show simulated transfer efficiencies of 70% (-1.5dB) for a phased array structure and 62.3% (-2.4dB) for a single feed structure. Single feed prototyping S-parameter results show coupling efficiencies of 25% (-5.9dB). All coupling measurements are at a distance 4r with reference to the largest transmitting coupler. / Master of Science
|
2 |
Textile Integrated Induction : Investigation of Textile Inductors for Wireless Power TransferYring, Malin January 2016 (has links)
This research has its basis in developments within the field of inductive powering and wireless power transfer, WPT, and more specifically one the branch within this field, which is called magnetic resonance coupling. This principle enables efficient power transfer from a transmitting unit to a receiving unit at a distance of some times the unit diameter. The developments within magnetic resonant coupling are together with the possibilities and challenges of today’s smart textile industry the starting point to investigate a novel textile-based product concept for WPT by combining both technologies. Multiple textile samples, consisting of cotton and electrically conductive copper yarns, were produced by weaving technique, additional assembling of electronic components were performed manually and several measurements were carried out to investigate the sample characteristics and the sample performance in terms of power transfer. The produced samples showed to behave similarly to conventional inductors and were able to transfer power over some distance.
|
3 |
Wave-Cavity Resonator: Experimental Investigation of an Alternative Energy DeviceReaume, Jonathan Daniel 21 December 2015 (has links)
A wave cavity resonator (WCR) is investigated to determine the suitability of the
device as an energy harvester in rivers or tidal flows. The WCR consists of coupling
between self-excited oscillations of turbulent flow of water in an open channel along the
opening of a rectangular cavity and the standing gravity wave in the cavity. The device
was investigated experimentally for a range of inflow velocities, cavity opening lengths,
and characteristic depths of the water. Determining appropriate models and empirical
relations for the system over a range of depths allows for accuracy when designing
prototypes and tools for determining the suitability of a particular river or tidal flow as a
potential WCR site. The performance of the system when coupled with a wave
absorber/generator is also evaluated for a range piston strokes in reference to cavity wave
height. Video recording of the oscillating free-surface inside the resonator cavity in
conjunction with free-surface elevation measurements using a capacitive wave gauge
provides representation of the resonant wave modes of the cavity as well as the degree of
the flow-wave coupling in terms of the amplitude and the quality factor of the associated
spectral peak. Moreover, application of digital particle image velocimetry (PIV) provides
insight into the evolution of the vortical structures that form across the cavity opening.
Coherent oscillations were attainable for a wide range of water depths. Variation of the
water depth affected the degree of coupling between the shear layer oscillations and the
gravity wave as well as the three-dimensionality of the flow structure. In terms of the
power investigation, conducted with the addition of a load cell and linear table-driven
piston, the device is likely limited to running low power instrumentation unless it can be
up-scaled. Up-scaling of the system, while requiring additional design considerations, is
not unreasonable; large-scale systems of resonant water waves and the generation of large
scale vortical structures due to tidal or river flows are even observed naturally. / Graduate / 0547 / 0548 / reaumejd@uvic.ca
|
Page generated in 0.1018 seconds