Engineering Commons^™

Application Of Survival Analysis Techniques To Probabilistic Assessment Of Fatigue In Steel Bridges, Azam Nabizadehdarabi

Theses and Dissertations

The fatigue of engineering materials under repetitive loading is a significant issue affecting the design and durability of components and systems in a variety of engineering-related applications including civil, mechanical, aerospace, automotive, and electronics. Many factors can affect the service life of a component or system under repetitive loading, such as the type of structure, loading, connection details, stress state, peak stress or stress range, surface condition, temperature, and environmental exposure. Currently, there is no comprehensive probabilistic approach that can systematically address all the factors that contribute to fatigue on a single mathematical platform. However, advanced analysis techniques developed for …

Optimization For Integration Of Plug-In Hybrid Electric Vehicles Into Distribution Grid, Shuaiyu Bu

Theses and Dissertations

Plug-in hybrid electric vehicles (PHEVs) feature combined electric and gasoline powertrains with internal combustion engine and electric motors powered by battery packs. The battery packs of PHEVs are mostly charged during off-peaks hours at lower prices and meanwhile absorb the excess power from the grid. Similarly, the power stored in the batteries can also flow back to the electric grid in response to ease the peak load demands.

With the increasing penetration and integration of PHEVs, the reliability of PHEVs is essential to overall power system reliability since the charging mechanisms of PHEVs can influence the reliability of power system. …

Large Scale Integration Of Electric Vehicles Into The Power Grid And Its Potential Effects On Power System Reliability, Mingzhi Zhang

Theses and Dissertations

In this thesis, the potential effects of large scale integration of electric vehicles into the power grid are discussed in both the beneficial and detrimental aspects. The literature review gives a comprehensive introduction about the existing smart charging algorithms. According to the system structure and market mechanism, the smart charging algorithms can be divided into centralized and distributed method. With the knowledge of driving patterns and charging characteristics of electric vehicles, both the centralized and decentralized smart charging algorithms are studied in this research.

Based on the smart charging pricing and sequential price update mechanism, a multi-agent based distributed smart …

Hvdc Transmission System Reliability Evaluation Based On Condition-Dependent Failure Models Of Converters And Transformers, Zibo Wang

Theses and Dissertations

Wind energy, especially offshore wind energy, is the focus of policy for countries that want to make significant use of renewable energy. With the development of semiconductor technology, high voltage direct current (HVDC) technology is being widely used for the transmission of wind power from offshore windfarms to onshore power grids. The application of HVDC technology can benefit the power system in many ways, such as operation security, reliability performance and economy. With the increasing number of applications of HVDC, the reliability performance of HVDC plays an important role in the overall power system reliability. Although the reliability of HVDC …

Reliability Of Bridge Superstructures In Wisconsin, Azam Nabizadehdarabi

Theses and Dissertations

ABSTRACT

RELIABILITY OF BRIDGE SUPERSTRUCTURES IN WISCONSIN

by

Azam Nabizadehdarabi

The University of Wisconsin-Milwaukee, 2015

Under the Supervision of Professor Habib Tabatabai

Bridge reliability analyses form the basis of modern bridge design provisions. Such analyses are also used to evaluate bridge condition and assess future maintenance needs. The majority of these reliability assessments are based on evaluating risks associated with the various load effects exceeding their corresponding resistance. However, bridge components such as decks and superstructures typically do not reach the end of their service lives by exceeding the strength limit states (structural failure). Survival analyses, which are commonly used …