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A pedagogical and performance edition of J. S. Bach's Violin sonata I in G minor, BWV 1001, transcribed for guitar: transcription, analysis, performance guide, pedagogical practice guide, and recording

Description

Johann Sebastian Bach's violin Sonata I in G minor, BWV 1001, is a significant and widely performed work that exists in numerous editions and also as transcriptions or arrangements for various other instruments, including the guitar. A pedagogical guitar performance

Johann Sebastian Bach's violin Sonata I in G minor, BWV 1001, is a significant and widely performed work that exists in numerous editions and also as transcriptions or arrangements for various other instruments, including the guitar. A pedagogical guitar performance edition of this sonata, however, has yet to be published. Therefore, the core of my project is a transcription and pedagogical edition of this work for guitar. The transcription is supported by an analysis, performance and pedagogical practice guide, and a recording. The analysis and graphing of phrase structures illuminate Bach's use of compositional devices and the architectural function of the work's harmonic gravities. They are intended to guide performers in their assessment of the surface ornamentation and suggest a reduction toward its fundamental purpose. The end result is a clarification of the piece through the organization of phrase structures and the prioritization of harmonic tensions and resolutions. The compiling process is intended to assist the performer in "seeing the forest from the trees." Based on markings from Bach's original autograph score, the transcription considers fingering ease on the guitar that is critical to render the music to a functional and practical level. The goal is to preserve the composer's indications to the highest degree possible while still adhering to the technical confines that allow for actual execution on the guitar. The performance guide provides suggestions for articulation, phrasing, ornamentation, and other interpretive decisions. Considering the limitations of the guitar, the author's suggestions are grounded in various concepts of historically informed performance, and also relate to today's early-music sensibilities. The pedagogical practice guide demonstrates procedures to break down and assimilate the musical material as applied toward the various elements of guitar technique and practice. The CD recording is intended to demonstrate the transcription and the connection to the concepts discussed. It is hoped that this pedagogical edition will provide a rational that serves to support technical decisions within the transcription and generate meaningful interpretive realizations based on principles of historically informed performance.

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2013

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Transmission expansion planning for large power systems

Description

Transmission expansion planning (TEP) is a complex decision making process that requires comprehensive analysis to determine the time, location, and number of electric power transmission facilities that are needed in the future power grid. This dissertation investigates the topic of

Transmission expansion planning (TEP) is a complex decision making process that requires comprehensive analysis to determine the time, location, and number of electric power transmission facilities that are needed in the future power grid. This dissertation investigates the topic of solving TEP problems for large power systems. The dissertation can be divided into two parts. The first part of this dissertation focuses on developing a more accurate network model for TEP study. First, a mixed-integer linear programming (MILP) based TEP model is proposed for solving multi-stage TEP problems. Compared with previous work, the proposed approach reduces the number of variables and constraints needed and improves the computational efficiency significantly. Second, the AC power flow model is applied to TEP models. Relaxations and reformulations are proposed to make the AC model based TEP problem solvable. Third, a convexified AC network model is proposed for TEP studies with reactive power and off-nominal bus voltage magnitudes included in the model. A MILP-based loss model and its relaxations are also investigated. The second part of this dissertation investigates the uncertainty modeling issues in the TEP problem. A two-stage stochastic TEP model is proposed and decomposition algorithms based on the L-shaped method and progressive hedging (PH) are developed to solve the stochastic model. Results indicate that the stochastic TEP model can give a more accurate estimation of the annual operating cost as compared to the deterministic TEP model which focuses only on the peak load.

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Date Created
2013

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Error detection and error correction for PMU data as applied to power system state estimators

Description

In modern electric power systems, energy management systems (EMSs) are responsi-ble for monitoring and controlling the generation system and transmission networks. State estimation (SE) is a critical `must run successful' component within the EMS software. This is dictated by the

In modern electric power systems, energy management systems (EMSs) are responsi-ble for monitoring and controlling the generation system and transmission networks. State estimation (SE) is a critical `must run successful' component within the EMS software. This is dictated by the high reliability requirements and need to represent the closest real time model for market operations and other critical analysis functions in the EMS. Tradi-tionally, SE is run with data obtained only from supervisory control and data acquisition (SCADA) devices and systems. However, more emphasis on improving the performance of SE drives the inclusion of phasor measurement units (PMUs) into SE input data. PMU measurements are claimed to be more accurate than conventional measurements and PMUs `time stamp' measurements accurately. These widely distributed devices meas-ure the voltage phasors directly. That is, phase information for measured voltages and currents are available. PMUs provide data time stamps to synchronize measurements. Con-sidering the relatively small number of PMUs installed in contemporary power systems in North America, performing SE with only phasor measurements is not feasible. Thus a hy-brid SE, including both SCADA and PMU measurements, is the reality for contemporary power system SE. The hybrid approach is the focus of a number of research papers. There are many practical challenges in incorporating PMUs into SE input data. The higher reporting rates of PMUs as compared with SCADA measurements is one of the salient problems. The disparity of reporting rates raises a question whether buffering the phasor measurements helps to give better estimates of the states. The research presented in this thesis addresses the design of data buffers for PMU data as used in SE applications in electric power systems. The system theoretic analysis is illustrated using an operating electric power system in the southwest part of the USA. Var-ious instances of state estimation data have been used for analysis purposes. The details of the research, results obtained and conclusions drawn are presented in this document.

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2013

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Analysis of synchronization and accuracy of synchrophasor measurements

Description

In electric power systems, phasor measurement units (PMUs) are capable of providing synchronized voltage and current phasor measurements which are superior to conventional measurements collected by the supervisory control and data acquisition (SCADA) system in terms of resolution and accuracy.

In electric power systems, phasor measurement units (PMUs) are capable of providing synchronized voltage and current phasor measurements which are superior to conventional measurements collected by the supervisory control and data acquisition (SCADA) system in terms of resolution and accuracy. These measurements are known as synchrophasor measurements. Considerable research work has been done on the applications of PMU measurements based on the as-sumption that a high level of accuracy is obtained in the field. The study in this dissertation is conducted to address the basic issue concerning the accuracy of actual PMU measurements in the field. Synchronization is one of the important features of PMU measurements. However, the study presented in this dissertation reveals that the problem of faulty synchronization between measurements with the same time stamps from different PMUs exists. A Kalman filter model is proposed to analyze and calcu-late the time skew error caused by faulty synchronization. In order to achieve a high level of accuracy of PMU measurements, inno-vative methods are proposed to detect and identify system state changes or bad data which are reflected by changes in the measurements. This procedure is ap-plied as a key step in adaptive Kalman filtering of PMU measurements to over-come the insensitivity of a conventional Kalman filter. Calibration of PMU measurements is implemented in specific PMU instal-lation scenarios using transmission line (TL) parameters from operation planning data. The voltage and current correction factors calculated from the calibration procedure indicate the possible errors in PMU measurements. Correction factors can be applied in on-line calibration of PMU measurements. A study is conducted to address an important issue when integrating PMU measurements into state estimation. The reporting rate of PMU measurements is much higher than that of the measurements collected by the SCADA. The ques-tion of how to buffer PMU measurements is raised. The impact of PMU meas-urement buffer length on state estimation is discussed. A method based on hy-pothesis testing is proposed to determine the optimal buffer length of PMU meas-urements considering the two conflicting features of PMU measurements, i. e. un-certainty and variability. Results are presented for actual PMU synchrophasor measurements.

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2012

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Solving for the low-voltage/large-angle power-flow solutions by using the holomorphic embedding method

Description

For a (N+1)-bus power system, possibly 2N solutions exists. One of these solutions

is known as the high-voltage (HV) solution or operable solution. The rest of the solutions

are the low-voltage (LV), or large-angle, solutions.

In this report, a recently developed non-iterative algorithm

For a (N+1)-bus power system, possibly 2N solutions exists. One of these solutions

is known as the high-voltage (HV) solution or operable solution. The rest of the solutions

are the low-voltage (LV), or large-angle, solutions.

In this report, a recently developed non-iterative algorithm for solving the power-

flow (PF) problem using the holomorphic embedding (HE) method is shown as

being capable of finding the HV solution, while avoiding converging to LV solutions

nearby which is a drawback to all other iterative solutions. The HE method provides a

novel non-iterative procedure to solve the PF problems by eliminating the

non-convergence and initial-estimate dependency issues appeared in the traditional

iterative methods. The detailed implementation of the HE method is discussed in the

report.

While published work focuses mainly on finding the HV PF solution, modified

holomorphically embedded formulations are proposed in this report to find the

LV/large-angle solutions of the PF problem. It is theoretically proven that the proposed

method is guaranteed to find a total number of 2N solutions to the PF problem

and if no solution exists, the algorithm is guaranteed to indicate such by the oscillations

in the maximal analytic continuation of the coefficients of the voltage power series

obtained.

After presenting the derivation of the LV/large-angle formulations for both PQ

and PV buses, numerical tests on the five-, seven- and 14-bus systems are conducted

to find all the solutions of the system of nonlinear PF equations for those systems using

the proposed HE method.

After completing the derivation to find all the PF solutions using the HE method, it

is shown that the proposed HE method can be used to find only the of interest PF solutions

(i.e. type-1 PF solutions with one positive real-part eigenvalue in the Jacobian

matrix), with a proper algorithm developed. The closet unstable equilibrium point

(UEP), one of the type-1 UEP’s, can be obtained by the proposed HE method with

limited dynamic models included.

The numerical performance as well as the robustness of the proposed HE method is

investigated and presented by implementing the algorithm on the problematic cases and

large-scale power system.

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Date Created
2015

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Impact of distributed photovoltaic generation and customer loads on power quality of a distribution system

Description

There has been a considerable growth in distributed photovoltaic (PV) genera-tion and its integration in electric power distribution systems. This has led to a change in the distribution system infrastructure. Properly planned distributed gen-eration can offer a variety of benefits

There has been a considerable growth in distributed photovoltaic (PV) genera-tion and its integration in electric power distribution systems. This has led to a change in the distribution system infrastructure. Properly planned distributed gen-eration can offer a variety of benefits for system operations and enhance opera-tional performance of the distribution system. However, high penetration of PV resources can give rise to operating conditions which do not arise in traditional systems and one of the potential issues that needs to be addressed involves impact on power quality of the system with respect to the spectral distortion in voltages and currents.

The test bed feeder model representing a real operational distribution feeder is developed in OpenDSS and the feeder modeling takes into consideration the ob-jective of analysis and frequency of interest. Extensive metering infrastructure and measurements are utilized for validation of the model at harmonic frequencies. The harmonic study performed is divided into two sections: study of impact of non-linear loads on total harmonic voltage and current distortions and study of impact of PV resources on high frequency spectral distortion in voltages and cur-rents. The research work incorporates different harmonic study methodologies such as harmonic and high frequency power flow, and frequency scan study. The general conclusions are presented based on the simulation results and in addition, scope for future work is discussed.

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Date Created
2014

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Development of improved dc network model for contingency analysis

Description

The development of new policies favoring integration of renewable energy into the grid has created a need to relook at our existing infrastructure resources and at the way the power system is currently operated. Also, the needs of electric energy

The development of new policies favoring integration of renewable energy into the grid has created a need to relook at our existing infrastructure resources and at the way the power system is currently operated. Also, the needs of electric energy markets and transmission/generation expansion planning has created a niche for development of new computationally efficient and yet reliable, simple and robust power flow tools for such studies. The so called dc power flow algorithm is an important power flow tool currently in use. However, the accuracy and performance of dc power flow results is highly variable due to the various formulations which are in use. This has thus intensified the interest of researchers in coming up with better equivalent dc models that can closely match the performance of ac power flow solution.

This thesis involves the development of novel hot start dc model using a power transfer distribution factors (PTDFs) approach. This document also discusses the problems of ill-conditioning / rank deficiency encountered while deriving this model. This model is then compared to several dc power flow models using the IEEE 118-bus system and ERCOT interconnection both as the base case ac solution and during single-line outage contingency analysis. The proposed model matches the base case ac solution better than contemporary dc power flow models used in the industry.

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Date Created
2014

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Distribution system modeling, analysis and design with high penetration of photovoltaic generation

Description

Present distribution infrastructure is designed mainly for uni-directional power flow with well-controlled generation. An increase in the inverter-interfaced photovoltaic (PV) systems requires a thorough re-examination of the design, operation, protection and control of distribution systems. In order to understand the

Present distribution infrastructure is designed mainly for uni-directional power flow with well-controlled generation. An increase in the inverter-interfaced photovoltaic (PV) systems requires a thorough re-examination of the design, operation, protection and control of distribution systems. In order to understand the impact of high penetration of PV generation, this work conducts an automated and detailed modeling of a power distribution system. The simulation results of the modeled distribution feeder have been verified with the field measurements.

Based on the feeder model, this work studies the impact of the PV systems on voltage profiles under various scenarios, including reallocation of the PV systems, reactive power support from the PV inverters, and settings of the load-tap changing transformers in coordination with the PV penetration. Design recommendations have been made based on the simulation results to improve the voltage profiles in the feeder studied.

To carry out dynamic studies related to high penetration of PV systems, this work proposes a differential algebraic equation (DAE) based dynamic modeling and analysis method. Different controllers including inverter current controllers, anti-islanding controllers and droop controllers, are designed and tested in large systems. The method extends the capability of the distribution system analysis tools, to help conduct dynamic analyses in large unbalanced distribution systems.

Another main contribution of this work is related to the investigation of the PV impacts on the feeder protection coordination. Various protection coordination types, including fuse-fuse, recloser-fuse, relay-fuse and relay-recloser have been studied. The analyses provide a better understanding of the relay and recloser settings under different configurations of the PV interconnection transformers, PV penetration levels, and fault types.

A decision tree and fuzzy logic based fault location identification process has also been proposed in this work. The process is composed of the off-line training of the decision tree, and the on-line analysis of the fault events. Fault current contribution from the PV systems, as well as the variation of the fault resistance have been taken into consideration. Two actual fault cases with the event data recorded were used to examine the effectiveness of the fault identification process.

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Date Created
2016

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Cluster-and-connect: an algorithmic approach to generating synthetic electric power network graphs

Description

Understanding the graphical structure of the electric power system is important

in assessing reliability, robustness, and the risk of failure of operations of this criti-

cal infrastructure network. Statistical graph models of complex networks yield much

insight into the underlying processes that are

Understanding the graphical structure of the electric power system is important

in assessing reliability, robustness, and the risk of failure of operations of this criti-

cal infrastructure network. Statistical graph models of complex networks yield much

insight into the underlying processes that are supported by the network. Such gen-

erative graph models are also capable of generating synthetic graphs representative

of the real network. This is particularly important since the smaller number of tradi-

tionally available test systems, such as the IEEE systems, have been largely deemed

to be insucient for supporting large-scale simulation studies and commercial-grade

algorithm development. Thus, there is a need for statistical generative models of

electric power network that capture both topological and electrical properties of the

network and are scalable.

Generating synthetic network graphs that capture key topological and electrical

characteristics of real-world electric power systems is important in aiding widespread

and accurate analysis of these systems. Classical statistical models of graphs, such as

small-world networks or Erd}os-Renyi graphs, are unable to generate synthetic graphs

that accurately represent the topology of real electric power networks { networks

characterized by highly dense local connectivity and clustering and sparse long-haul

links.

This thesis presents a parametrized model that captures the above-mentioned

unique topological properties of electric power networks. Specically, a new Cluster-

and-Connect model is introduced to generate synthetic graphs using these parameters.

Using a uniform set of metrics proposed in the literature, the accuracy of the proposed

model is evaluated by comparing the synthetic models generated for specic real

electric network graphs. In addition to topological properties, the electrical properties

are captured via line impedances that have been shown to be modeled reliably by well-studied heavy tailed distributions. The details of the research, results obtained and

conclusions drawn are presented in this document.

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Date Created
2015

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Energy market transparency: analyzing the impacts of constraint relaxation and out-of-market correction practices in electric energy markets

Description

This work presents research on practices in the day-ahead electric energy market, including replication practices and reliability coordinators used by some market operators to demonstrate the impact these practices have on market outcomes. The practice of constraint relaxations similar to

This work presents research on practices in the day-ahead electric energy market, including replication practices and reliability coordinators used by some market operators to demonstrate the impact these practices have on market outcomes. The practice of constraint relaxations similar to those an Independent System Operator (ISO) might perform in day-ahead market models is implemented. The benefits of these practices are well understood by the industry; however, the implications these practices have on market outcomes and system security have not been thoroughly investigated. By solving a day-ahead market model with and without select constraint relaxations and comparing the resulting market outcomes and possible effects on system security, the effect of these constraint relaxation practices is demonstrated.

Proposed market solutions are often infeasible because constraint relaxation practices and approximations that are incorporated into market models. Therefore, the dispatch solution must be corrected to ensure its feasibility. The practice of correcting the proposed dispatch solution after the market is solved is known as out-of-market corrections (OMCs), defined as any action an operator takes that modifies a proposed day-ahead dispatch solution to ensure operating and reliability requirements. The way in which OMCs affect market outcomes is illustrated through the use of different corrective procedures. The objective of the work presented is to demonstrate the implications of these industry practices and assess the impact these practices have on market outcomes.

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Date Created
2016