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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Estimation of wind energy near the earth's surface

Bootman, Steven Randall January 2011 (has links)
Typescript. / Digitized by Kansas Correctional Industries
142

First assessment of the magnetic-hydrostatic main bearing proposed for the duck wave-energy converter

Anderson, Colin George January 1985 (has links)
No description available.
143

Impact of decentralized power on power systems

Morales, Ana A B 28 September 2006 (has links)
Wind generation is one of the most successful sources of renewable energy for the production of electrical energy. Wind power offers relatively high capacities, with generation costs that are becoming competitive with conventional energy sources. However, a major problem to its effective use as a power source is the fact that it is both intermittent and diffuse as wind speed is highly variable and site-specific. This is translated in large voltage and frequency excursions and dynamically unstable situations when fast wind power changes. Very high wind speeds will result in sudden loss of wind generator production. The requirement to ensure that sufficient spinning reserve capacity exists within the system to compensate for sudden loss of generation becomes crucial. From the utilities operators’point of view, the primary objective is the security of the system, followed by the quality of the supplied power. In order to guard the system security and quality of supply and retain acceptable levels, a maximum allowed wind power penetration (wind margin) is normally assumed by the operators. Very conservative methods are used to assess the impact of wind power and the consequences turn to under-exploitation of the wind power potential in a given region. This thesis presents the study of actual methods of wind power assessment, divided into three parts: 1. Part I: Impact on the Security of Power Systems 2. Part II: Impact on the Power Quality 3. Part III: Impact on the Dynamic Security of Power Systems
144

Modelling the response of tides in an estuary to the optimised operation of a tidal power plant

Alderson, S. G. January 1984 (has links)
No description available.
145

The development of a multi-tide tidal energy prediction model and its application to the proposed Mersey Barrage

Austin, Richard Arthur January 1990 (has links)
No description available.
146

An approach to the mathematical modelling of a shoreline wave power station

Linden, Brendan Malachy January 1995 (has links)
No description available.
147

A study of induction generator performance in a wave energy conversion system

Xu, Mingzhou January 1995 (has links)
No description available.
148

Space Vector Modulation of Multi-level and Multi-module Converters for High Power Applications

Saeedifard, Maryam 26 February 2009 (has links)
This thesis presents and investigates Space Vector Modulation (SVM) switching strategies for (i) a multi-level Diode-Clamped Converter (DCC) and (ii) a multi-module Voltage-Sourced Converter (VSC) system in which each module is a conventional two-level VSC. Although the SVM strategies are general and applicable for n-level DCC and n-module VSC systems, this text only concentrates on five-level DCC and four-module VSC systems. For a five-level DCC, a computationally efficient SVM algorithm is proposed. The algorithm, that is based on a classifier Neural Network (NN), reduces the computational time for the SVM realization. Therefore, adequate saving of processor execution time, in each sampling period of SVM, is provided to carry out other functions, e.g. the calculations required for DC-capacitor voltage balancing task. The thesis also proposes a DC-capacitor voltage balancing strategy to counteract the voltage drift phenomenon of (i) a passive-front-end five-level DCC, and (ii) a back-to-back connected five-level DCC system. The proposed balancing strategy, that is based on augmenting the proposed SVM algorithm, takes advantage of the redundant switching states to minimize a quadratic cost function associated with voltage deviations of the DC-capacitors. The salient features of the proposed balancing strategy are (i) online calculation of SVM to select the best switching states, (ii) minimization of switching frequency, (iii) minimization of the THD content of the AC-side voltage, and (iv) no requirement for additional power circuitry. For a four-module VSC system a sequential sampling SVM strategy is proposed. The proposed strategy (i) provides harmonic cancellation/minimization at the net AC-side voltage of the multi-module VSC system, and (ii) offers a low switching frequency for each VSC module. Technical feasibility of the proposed SVM strategies for a five-level DCC and a four-module VSC system, as a STATCOM and a back-to-back HVDC system, are investigated and presented. The studies are conducted in the time-domain, in the PSCAD/EMTDC software environment.
149

Power Profiling of Network Switches

Chilukuri, Megh Phani Dutt January 2017 (has links)
Context In the present world, there is an increase in the usage of the telecommunication networking services, as there is a need of efficient networking services in various fields which can be obtained by using the efficient networking components. For that purpose we have to know about the components parameters. One of the most important parameter is the energy usage of networking components. Therefore, there is a need in power profiling of the network switches. Objectives The objective of this research is to profile the power usage of different network components(Switches) for various load scenarios. Power measurements are done by using the open energy monitoring tool called emonpi. Methods The research method has been carried out by using an experimental test bed. In this research, we are going to conduct the experiments with different configurations to obtain different load conditions for sources and destinations which will be passed through DUT(Device Under Test). For that DUT’s we will measure power usage by monitoring tool called emonpi. Then the experiments are conducted for different load scenarios for different switches and results are discussed. Conclusion From the results obtained, the Power profiles of different DUT’s are tabulated and analyzed. These were done under different ports and load scenarios for Cisco2950, Cisco3560 and Netgear GS-724T. From the results and analysis it can be stated that the power usage of Cisco 2950 is having the maximum power usage in all the considered scenarios with respect to packet rate and also number of active ports. The Netgear-GS724T is having the minimum power usage from the three switches as it having the green switch characteristics in all scenarios. And the Cisco 3560 is in between the above two switches as it is having energy efficient management from Cisco. From this we have proposed a simple model for energy/power measurement.
150

Power line carrier communication

Razani, Mohammad January 2010 (has links)
Digitized by Kansas Correctional Industries

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