Engineering Commons^™

Novel Control And Harmonics Impact Of Pv Solar Farms, Byomakesh Das

Electronic Thesis and Dissertation Repository

This thesis presents a novel application of Photovoltaic (PV) solar system inverter, both during night and day, as a dynamic reactive power compensator STATCOM. This technology, termed PV-STATCOM, is designed and developed for power factor correction in the networks of two utilities: Bluewater Power, Sarnia, and London Hydro. This thesis further describes for the first time, the harmonic impact studies on a utility distribution network in presence of the largest PV solar farm in Canada.

This novel utilization of a PV-STATCOM for power factor correction of induction motor loads is demonstrated with (i) electromagnetic transient simulation in EMTDC/PSCAD software, (ii) …

Dynamic Vulnerability Assessment Of Highway And Railway Bridges, Mehdi Mohseni

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Dynamic loads can cause severe damage to bridges, and lead to malfunction of transportation networks. A comprehensive understanding of the nature of the dynamic loads and the structural response of bridges can prevent undesired failures while keeping the cost-safety balance. Dissimilar to the static behavior, the dynamic response of bridges depends on several structural parameters such as material properties, damping and mode shapes. Furthermore, dynamic load characteristics can significantly change the structural response. In most cases, complexity and involvement of numerous parameters require the designer to investigate the bridge response via a massive numerical study.

This dissertation targets three main …

Investigation Of Auxiliary Winding Harmonic Resonance Phenomena In Single Phase Induction Motors, Gaurav Singh

All Theses

In recent years, the proliferation of single phase power electronics based loads has given rise to a number of power quality issues in the power grid. Harmonics in voltage and current waveforms are one of the biggest problems in this family of power quality issues. Until some years back, power system utilities did not consider harmonics due to small single phase loads to be a big problem. In fact, only large loads were considered as potential hotspots for power quality problems. However, the advent of compact fluorescent lamps (CFLs), personal computers and consumer electronic devices, which utilize rectifier front ends, …

Using Inductance As A Tuning Parameter For Rf Meta-Atoms, Derrick Langley, Ronald Coutu Jr., Peter J. Collins

Faculty Publications

The resonant frequency of metamaterials structured with split ring resonator (SRR) meta-atoms is determined primarily through the capacitance and inductance of the individual meta-atoms. Two designs that vary inductance incrementally were modeled, simulated, fabricated, and tested to investigate the role inductance plays in metamaterial designs. The designs consisted of strategically adding sections to the SRR to increase the inductance, but in a manner that minimized capacitance variations. Each design showed a shift in resonant frequency that was proportional to the length of the added section. As the length of each section was increased, the resonant frequency shifted from 2.78 GHz …

Using Inductance As A Tuning Parameter For Rf Meta-Atoms, Derrick Langley, Ronald A. Coutu Jr., Peter J. Collins

Electrical and Computer Engineering Faculty Research and Publications

The resonant frequency of metamaterials structured with split ring resonator (SRR) meta-atoms is determined primarily through the capacitance and inductance of the individual meta-atoms. Two designs that vary inductance incrementally were modeled, simulated, fabricated, and tested to investigate the role inductance plays in metamaterial designs. The designs consisted of strategically adding sections to the SRR to increase the inductance, but in a manner that minimized capacitance variations. Each design showed a shift in resonant frequency that was proportional to the length of the added section. As the length of each section was increased, the resonant frequency shifted from 2.78 GHz …

Resonance Frequencies Of A Spherical Aluminum Shell Subject To Static Internal Pressure, Andrew A. Piacsek, Sami Abdul-Wahid, Robert Taylor

All Faculty Scholarship for the College of the Sciences

Measurements of the vibrational response of a spherical aluminum shell subject to changes in the interior pressure clearly demonstrate that resonance frequencies shift higher as the pressure is increased. The frequency shift appears to be smaller for longitudinal modes than for bending wave modes. The magnitude of frequency shift is comparable to analytical predictions made for thin cylindrical shells. Changes in the amplitudes of resonance peaks are also observed. A possible application of this result is a method for noninvasively monitoring pressure changes inside sealed containers, including intracranial pressure in humans.

Resonance Damping In Ferromagnets And Ferroelectrics, Allan Widom, Somu Sivasubramanian, Carmine Vittoria, S. Yoon, Yogendra N. Srivastava

Carmine Vittoria

The phenomenological equations of motion for the relaxation of ordered phases of magnetized and polarized crystal phases can be developed in close analogy with one another. For the case of magnetized systems, the driving magnetic field intensity toward relaxation was developed by Gilbert. For the case of polarized systems, the driving electric field intensity toward relaxation was developed by Khalatnikov. The transport times for relaxation into thermal equilibrium can be attributed to viscous sound wave damping via magnetostriction for the magnetic case and electrostriction for the polarization case.

Frequency-Dependence Of The Ferromagnetic-Resonance Linewidth Of Barium Ferrite, M. Elrayess, J. B. Sokoloff, C. Vittoria, W. Spurgeon

Carmine Vittoria

Ferromagnetic resonance was measured in both a swept frequency mode of operation, in which the magnetic field was fixed, and a field swept mode, using field modulation techniques. Single-crystal spheres of 0.381, 0.305, and 0.483 mm in diameter were inserted in the waveguide and transmission was observed in the measurement. The g values for all the spheres averaged to 2.052 ± 0.011 and the uniaxial anisotropy field was 16.4 kOe. Our measurements show that the linewidth of barium ferrite is nearly independent of resonant frequency from 48 to 105 G Hz. This is in disagreement with the Kasuya-LeCraw two-magnon-one-phonon mechanism, …

Simulations Of Ferrite-Dielectric-Wire Composite Negative Index Materials, Frederic J. Rachford, Douglas N. Armstead, Vincent G. Harris, Carmine Vittoria

Carmine Vittoria

We perform extensive finite difference time domain simulations of ferrite based negative index of refraction composites. A wire grid is employed to provide negative permittivity. The ferrite and wire grid interact to provide both negative and positive index of refraction transmission peaks in the vicinity of the ferrite resonance. Notwithstanding the extreme anisotropy in the index of refraction of the composite, negative refraction is seen at the composite air interface allowing the construction of a focusing concave lens with a magnetically tunable focal length.

Selective Laser Excitation Spectroscopy Of Gallium And Phosphorous In Germanium, C. A. Freeth, R. A. Lewis

Carey Freeth

Shallow impurity states of donors and acceptors in Ge have been investigated by far-infrared laser magnetospectroscopy. The Zeeman splitting of the impurity states produces resonant absorption of the laser radiation at certain magnetic fields. The data are compared to measurements made using a conventional spectrometer and good agreement is found.

Effective Permittivity Of Dense Random Particulate Plasmonic Composites, Satvik N. Wani, Ashok Sangani, Radhakrishna Sureshkumar

Biomedical and Chemical Engineering - All Scholarship

No abstract provided.