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Joint Optimization Of Power Allocation And Training Duration For Uplink Multiuser Mimo Communications, Songtao Lu, Zhengdao Wang 2018 Iowa State University

Joint Optimization Of Power Allocation And Training Duration For Uplink Multiuser Mimo Communications, Songtao Lu, Zhengdao Wang

Zhengdao Wang

In this paper, we consider a multiuser multiple-input multiple-output (MU-MIMO) communication system between a base station equipped with multiple antennas and multiple mobile users each equipped with a single antenna. The uplink scenario is considered. The uplink channels are acquired by the base station through a training phase. Two linear processing schemes are considered, namely maximum-ratio combining (MRC) and zero-forcing (ZF). We optimize the training period and optimal training energy under the average and peak power constraint so that an achievable sum rate is maximized.


A Fault Location Algorithm For Unbalanced Distribution System Without Fault Type Information, Yizhe Li 2018 University of Kentucky

A Fault Location Algorithm For Unbalanced Distribution System Without Fault Type Information, Yizhe Li

Theses and Dissertations--Electrical and Computer Engineering

Power system faults normally result in system damage, profit loss and consumer dissatisfaction. Consequently, there is a strong demand on precise and fast fault location estimation for power system to minimize the system restoration time.

This paper examines a method to locate short-circuit faults on a distribution system with unbalanced loads without fault type information. Bus impedance matrix technique was harnessed in the fault location estimation algorithm. The system data including line impedances, source impedance and distribution system layout was assumed to be known factors, hence pre-fault bus impedance can be calculated and implemented into the algorithm. Corresponding methods to ...


Harmonics Elimination In Three Phase Cascade H-Bridge Multilevel Inverter Using Virtual Stage Pwm, Amro Quedan 2017 University of Nebraska-Lincoln

Harmonics Elimination In Three Phase Cascade H-Bridge Multilevel Inverter Using Virtual Stage Pwm, Amro Quedan

Architectural Engineering -- Dissertations and Student Research

The multilevel inverters are one of the great solutions that are proposed to satisfy the demand for high-power application and the significant integration of renewable energy. The conversion process from DC to AC must be done at high efficiency to decrease the energy loss and to ensure the electric grid power quality. The Total Harmonic Distortion (THD) is the most important feature that indicates the efficiency of the conversion process. In this research, due to the advantages of the cascade H-bridge inverter over other topologies, it has been used with the virtual stage PWM technique to investigate two different methods ...


Swing Contracts With Dynamic Reserves For Flexible Service Management, Shanshan Ma, Zhaoyu Wang, Leigh Tesfatsion 2017 Iowa State University

Swing Contracts With Dynamic Reserves For Flexible Service Management, Shanshan Ma, Zhaoyu Wang, Leigh Tesfatsion

Leigh Tesfatsion

The increasing penetration of variable energy resources in modern electric power systems requires additional flexibility in ancillary service provision to maintain reliable and efficient grid operations. However, full recognition and appropriate compensation of this flexibility is difficult to ensure within current power market designs due to rigidities in service definitions and requirements. For example, reserve requirements (RRs) are typically set in advance at administratively determined levels. If RRs are too large, wasteful expenditures result; and, if RRs are too small, high real-time costs are incurred for peak generation and/or load curtailment. To address these problems, this paper proposes a ...


A New Single-Phase Single-Stage Ac-Dc Stacked Flyback Converter With Active Clamp Zvs, Yuntong Li 2017 The University of Western Ontario

A New Single-Phase Single-Stage Ac-Dc Stacked Flyback Converter With Active Clamp Zvs, Yuntong Li

Electronic Thesis and Dissertation Repository

Single-stage AC-DC converters integrate an AC-DC front-end converter with a DC-DC back-end converter. Compared with conventional two-stage AC-DC converters, single-stage AC-DC converters use less components and only one controller, which is used to regulate the output voltage. As a result, the cost, size and complexity of AC-DC converters can be reduced, but single-stage converters do not perform as well as two-stage converters, and most have drawbacks that are related to the fact that the DC bus voltage is not controlled an can become excessive.

A new single-phase single-stage AC-DC converter that uses stacked flyback converters is proposed in this thesis ...


A Novel Ac-Dc Interleaved Zcs-Pwm Boost Converter, Ramtin Rasoulinezhad 2017 The University of Western Ontario

A Novel Ac-Dc Interleaved Zcs-Pwm Boost Converter, Ramtin Rasoulinezhad

Electronic Thesis and Dissertation Repository

AC-DC converters with input power factor correction (PFC) that consist of two or more interleaved boost converter modules are popular in industry. PFC is a must in today’s AC-DC converters as their input current must meet harmonic standards set by regulatory agencies. With interleaving, the input current of each module can make to be discontinuous and the size of their input inductors since interleaving can reduce the high ripple in each module and produce a net input current with a ripple that is comparable to that achieved with a single boost converter module with a large input inductor.

In ...


Impacts Of Power System-Tied Distributed Generation On The Performance Of Protection Systems, Terver T. Maor 2017 University of Texas at Tyler

Impacts Of Power System-Tied Distributed Generation On The Performance Of Protection Systems, Terver T. Maor

Electrical Engineering Theses

The dispersed integration of smaller power units in the existing utility grid is the new trend. This is largely due to changes in the power generation and distribution markets. The combination of rising cost of new construction, deregulations and improved newer power equipment technologies suitable for deferred expansions make the new trend very attractive to power companies and independent investors. Until recently, other contributions to power distribution systems from such sources as standby units were considered negligible and therefore unaccounted for during the design and operation of power systems. This view has drastically changed, largely due to the increasing penetration ...


A Comparison Between Different Snubbers For Flyback Converters, Adel Alganidi 2017 The University of Western Ontario

A Comparison Between Different Snubbers For Flyback Converters, Adel Alganidi

Electronic Thesis and Dissertation Repository

The DC-DC flyback power converter is widely used in low power commercial and industrial applications ( > 150 W) such as in computers, telecom, consumer electronics because it is one of the simplest and least expensive converter topologies with transformer isolation. Its main power circuit consists of just a semiconductor device like a MOSFET operating as a switch, a transformer, an output diode and an output filter capacitor. The converter switch, however, is susceptible to high voltage spikes due to the interaction between its output capacitance and the leakage inductance of the transformer. These spikes can exceed the ratings of the switch ...


A Silicon Carbide Power Management Solution For High Temperature Applications, Robert Murphree 2017 University of Arkansas, Fayetteville

A Silicon Carbide Power Management Solution For High Temperature Applications, Robert Murphree

Theses and Dissertations

The increasing demand for discrete power devices capable of operating in high temperature and high voltage applications has spurred on the research of semiconductor materials with the potential of breaking through the limitations of traditional silicon. Gallium nitride (GaN) and silicon carbide (SiC), both of which are wide bandgap materials, have garnered the attention of researchers and gradually gained market share. Although these wide bandgap power devices enable more ambitious commercial applications compared to their silicon-based counterparts, reaching their potential is contingent upon developing integrated circuits (ICs) capable of operating in similar environments.

The foundation of any electrical system is ...


Mppt Control For Solar Splash Photovoltaic Array, Kelsey Zenko 2017 University of Arkansas, Fayetteville

Mppt Control For Solar Splash Photovoltaic Array, Kelsey Zenko

Mechanical Engineering Undergraduate Honors Theses

This thesis demonstrates the ability to model and simulate the operation of Maximum Power Point Tracking, MPPT. Moreover, the MPPT technology is contextualized within the confines of the Solar Splash competition to provide the foundation for future model development and simulation for optimal competition performance. MatLab Simulink was used to model the solar panel's operation. A MPPT algorithm was written using the perturb and observe method and was implemented in the model using a buck DC to DC converter. The performance of the model with hardware in the loop using Typhoon and dSPACE, which demonstrated how the actual hardware ...


Dc-To-Dc Buck Converter, Kyle Christopher Roman 2017 California Polytechnic State University, San Luis Obispo

Dc-To-Dc Buck Converter, Kyle Christopher Roman

Electrical Engineering

The growth of sustainable energy requires many components to work in harmony creating one efficient and effective system. Sustainable energy generation that produces a DC current varying in voltage requires a subsystem to convert voltage to a practical and usable value. The DC to DC Buck converter converts high DC solar generated voltage to a 12V output. This Modular -Level power electronic (MLPE) device performs as a solar charge controller for small lithium ion batteries. Fluctuating voltage levels generated by Photovoltaic cells makes the solar controller a critical part of the solar system. Regulating the DC voltage allows safe and ...


Energy Shaping Control For Stabilization Of Interconnected Voltage Source Converters In Weakly-Connected Ac Microgrid Systems, Nadia Lenora Carmita Smith 2017 University of Arkansas, Fayetteville

Energy Shaping Control For Stabilization Of Interconnected Voltage Source Converters In Weakly-Connected Ac Microgrid Systems, Nadia Lenora Carmita Smith

Theses and Dissertations

With the ubiquitous installations of renewable energy resources such as solar and wind, for decentralized power applications across the United States, microgrids are being viewed as an avenue for achieving this goal. Various independent system operators and regional transmission operators such as Southwest Power Pool (SPP), Midcontinent System Operator (MISO), PJM Interconnection and Electric Reliability Council of Texas (ERCOT) manage the transmission and generation systems that host the distributed energy resources (DERs). Voltage source converters typically interconnect the DERs to the utility system and used in High voltage dc (HVDC) systems for transmitting power throughout the United States. A microgrid ...


A Case Study: An Economic Evaluation Of Liqufied Natural Gas (Lng) Fuel For New Ships Of Korean Ship Owners, Hyuntae Kim 2017 World Maritime University

A Case Study: An Economic Evaluation Of Liqufied Natural Gas (Lng) Fuel For New Ships Of Korean Ship Owners, Hyuntae Kim

World Maritime University Dissertations

No abstract provided.


Lng As A Marine Fuel In Malta: Case Study : Regulatory Analysis And Potential Scenarios For Lng Bunkering Infrastructure, Mark Philip Cassar 2017 World Maritime University

Lng As A Marine Fuel In Malta: Case Study : Regulatory Analysis And Potential Scenarios For Lng Bunkering Infrastructure, Mark Philip Cassar

World Maritime University Dissertations

No abstract provided.


Investigation Of Auxiliary Power Potentials Of Solar Photovoltaic Applications On Dry Bulk Carrier Ships, Wandifa Saidyleigh 2017 World Maritime University

Investigation Of Auxiliary Power Potentials Of Solar Photovoltaic Applications On Dry Bulk Carrier Ships, Wandifa Saidyleigh

World Maritime University Dissertations

No abstract provided.


Performance And Mitigation Strategy Of Distributed Ac-Stacked Pv Inverter Architecture Under Grid Background Harmonics, Namwon Kim, Hamidreza Jafarian, Babak Parkhideh, Johan Enslin 2017 University of North Carolina at Charlotte

Performance And Mitigation Strategy Of Distributed Ac-Stacked Pv Inverter Architecture Under Grid Background Harmonics, Namwon Kim, Hamidreza Jafarian, Babak Parkhideh, Johan Enslin

Hamidreza Jafarian

Grid-tied Photovoltaic (PV) inverters are required to have harmonics mitigation control to reduce harmonics distortion on the output current caused by the impact of grid background harmonics. In this paper, a decentralized control strategy for reduction of the impact of distorted grid voltage on the AC-stacked PV inverter architecture is proposed. Two control schemes with the selective harmonics mitigation strategy and without any handshaking among the inverters are proposed for this architecture and analyzed to present the improvement of the power quality as well as the operating margin of the architecture. The proposed methods are analyzed by impedance analysis and ...


A Distributed Active And Reactive Power Control For Grid-Tied Cascaded H-Bridge Pv Inverter System Using Relative Gain Array Approach, Hamidreza Jafarian, Namwon Kim, Babak Parkhideh 2017 University of North Carolina at Charlotte

A Distributed Active And Reactive Power Control For Grid-Tied Cascaded H-Bridge Pv Inverter System Using Relative Gain Array Approach, Hamidreza Jafarian, Namwon Kim, Babak Parkhideh

Hamidreza Jafarian

The main objective of this paper is to propose a decentralized control approach for active and reactive power control of grid-tied cascaded H-bridge PV inverter architecture. The decentralized controller allows fully distributed architecture both in terms of control and physical implementation of a PV system, resulting in higher reliability and potentially lower cost. The proposed control approach not only maintaining the balance of the system but also by sending supervisory commands to only one inverter minimizes the required communications for controlling active and reactive power. Detailed modeling and analysis are provided to show the feasibility of the proposed decentralized approach ...


Quantifying Forecast Uncertainty In The Energy Domain, Mohammad Saber 2017 Marquette University

Quantifying Forecast Uncertainty In The Energy Domain, Mohammad Saber

Dissertations (2009 -)

This dissertation focuses on quantifying forecast uncertainties in the energy domain, especially for the electricity and natural gas industry. Accurate forecasts help the energy industry minimize their production costs. However, inaccurate weather forecasts, unusual human behavior, sudden changes in economic conditions, unpredictable availability of renewable sources (wind and solar), etc., represent uncertainties in the energy demand-supply chain. In the current smart grid era, total electricity demand from non-renewable sources influences by the uncertainty of the renewable sources. Thus, quantifying forecast uncertainty has become important to improve the quality of forecasts and decision making. In the natural gas industry, the task ...


Leveraging Mapreduce And Synchrophasors For Real-Time Anomaly Detection In The Smart Grid, Suzanne J. Matthews, Aaron St. Leger 2017 United States Military Academy

Leveraging Mapreduce And Synchrophasors For Real-Time Anomaly Detection In The Smart Grid, Suzanne J. Matthews, Aaron St. Leger

Research Papers

The rapid detection of anomalous behavior in SCADA systems such as the U.S. power grid is critical for system resiliency and operator response in cases of power fluctuations due to hazardous weather conditions or other events. Phasor measurement units are time synchronized devices that provide accurate synchrophasor measurements in power grids. The rapid deployment of PMUs enable improved real-time situational awareness to grid operators through wide area measurement systems. However, the quantity and rate of measurements obtained from PMUs is significantly higher than traditional devices, and continues to grow as more are deployed. Efficient algorithms for processing large-scale PMU ...


Optimizing Distributed Energy Resources On A Distribution Feeder, Bill Henry, Stephen MacDonald, Nicole Wehner, Gabe McBride, Tyler Groth 2017 Portland State University

Optimizing Distributed Energy Resources On A Distribution Feeder, Bill Henry, Stephen Macdonald, Nicole Wehner, Gabe Mcbride, Tyler Groth

Engineering and Technology Management Student Projects

The purpose of this study is to optimize a set of distributed energy resources (DERs) on an electric utility distribution level feeder. A DER is a decentralized resource, usually located at end-use electric utility customer sites, that stores or generates electricity – such as batteries and rooftop photovoltaic solar, or in the case of demand response, in which the utility has the ability to manage electricity consumption to the benefit of distribution grid operation. The aggregation and optimization of a set of DERs of disparate operating characteristics, over a period of three years is performed and the methods employed explained.

This ...


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