Controls and Control Theory Commons^™

Control Design Of A Single-Phase Dc/Ac Inverter For Pv Applications, Haoyan Liu

Graduate Theses and Dissertations

This thesis presents controller designs of a 2 kVA single-phase inverter for photovoltaic (PV) applications. The demand for better controller designs is constantly rising as the renewable energy market continues to rapidly grow. Some background research has been done on solar energy, PV inverter configurations, inverter control design, and hardware component selection. Controllers are designed both for stand-alone and grid-connected modes of operation. For stand-alone inverter control, the outer control loop regulates the filter capacitor voltage. Combining the synchronous frame outer control loop with the capacitor current feedback inner control loop, the system can achieve both zero steady-state error and …

Impact Of Clustering Microgrids On Their Stability And Resilience During Blackouts, Mahmoud S. Saleh, Ammar Althaibani, Yusef Esa, Yassine Mhandi, Ahmed Mohamed

Publications and Research

In this paper, the impact of clustering multiple microgrids during blackouts, on their stability and supply availability, will be investigated. Microgrids have the capability of satisfying their emergency loads during blackouts. However, distributed energy resources (DERs)-dominated microgrids are affected by the uncertainty of their input energy supply, e.g. impact of solar irradiance on photovoltaic (PV) output. Moreover, an individual islanded microgrid is prone to instability issues due to large sudden load/generation changes. In order to increase the supply security, and enhance system stability, we propose to use the existing distribution grid infrastructure, if applicable, during blackouts to form microgrid clusters. …

Predictive Control Of Power Grid-Connected Energy Systems Based On Energy And Exergy Metrics, Meysam Razmara

Dissertations, Master's Theses and Master's Reports

Building and transportation sectors account for 41% and 27% of total energy consumption in the US, respectively. Designing smart controllers for Heating, Ventilation and Air-Conditioning (HVAC) systems and Internal Combustion Engines (ICEs) can play a key role in reducing energy consumption. Exergy or availability is based on the First and Second Laws of Thermodynamics and is a more precise metric to evaluate energy systems including HVAC and ICE systems. This dissertation centers on development of exergy models and design of model-based controllers based on exergy and energy metrics for grid-connected energy systems including HVAC and ICEs.

In this PhD dissertation, …

Electromechanics Of An Ocean Current Turbine, Vasileios Tzelepis

LSU New Orleans Theses and Dissertations

The development of a numeric simulation for predicting the performance of an Ocean Current Energy Conversion System is presented in this thesis along with a control system development using a PID controller for the achievement of specified rotational velocity set-points. In the beginning, this numeric model is implemented in MATLAB/Simulink® and it is used to predict the performance of a three phase squirrel single-cage type induction motor/generator in two different cases. The first case is a small 3 meter rotor diameter, 20 kW ocean current turbine with fixed pitch blades, and the second case a 20 …

Design And Control Of A Bidirectional Dual Active Bridge Dc-Dc Converter To Interface Solar, Battery Storage, And Grid-Tied Inverters, Kenny George

Electrical Engineering Undergraduate Honors Theses

In order to further reduce the size of today’s power converters, wide bandgap semiconductor technologies are being explored. These devices, such as silicon carbide (SiC), have been shown to outperform their silicon counterparts when used in high frequency switching, high temperature, and high voltage applications. These properties make them highly desirable in the bidirectional dual active bridge power converter. Being an isolated converter topology, the dual active bridge employs a transformer to provide step-up/step-down functionality and galvanic isolation for the converter. Transformers, as well as other passive components such as inductors and capacitors may be reduced in size when higher …

Fast Sequence Component Analysis For Attack Detection In Synchrophasor Networks, Jordan Landford, Rich Meier, Richard Barella, Xinghui Zhao, Robert B. Bass, Scott Wallace

Electrical and Computer Engineering Faculty Publications and Presentations

Modern power systems have begun integrating synchrophasor technologies into part of daily operations. Given the amount of solutions offered and the maturity rate of application development it is not a matter of "if" but a matter of "when" in regards to these technologies becoming ubiquitous in control centers around the world. While the benefits are numerous, the functionality of operator-level applications can easily be nullified by injection of deceptive data signals disguised as genuine measurements. Such deceptive action is a common precursor to nefarious, often malicious activity. A correlation coefficient characterization and machine learning methodology are proposed to detect and …

The Electric Reel For Soccer Fields, Stephen Taylor

Electrical Engineering

Painting a soccer field consumes too much time. The process of reeling the string after laying out string along the field needs to improve. As a result, my project addresses improvements in how the workers retrieve the string through the production of an electric reel. This electric reel allows the worker to have control of the speed, direction, and on/off state of the device. Direction control allows the user ability to reel and unwind the string. Variable speed allows the user to control how fast the reel unwinds and reels the string. The device gathers string in an orderly manner …

Universal Programmable Battery Charger With Optional Battery Management System, Michael Duke Desando

Master's Theses

This report demonstrates improvements made in battery charging and battery management technology through the design of a universal programmable battery charger with optional battery management system attachment. This charger offers improvements in charge efficiency and unique battery charging algorithms to charge a variety of battery chemistries with variety of power requirements. Improvements in efficiency result from a synchronous Buck Controller topology as compared to previous universal chargers that use asynchronous Buck-Boost Converter topologies. This battery charger also surpasses current universal battery chargers by offering different charge modes for different battery chemistries. Charge modes provide the user an option between extending …

Design Of Energy Storage Controls Using Genetic Algorithms For Stochastic Problems, Si Chen

Theses and Dissertations--Electrical and Computer Engineering

A successful power system in military applications (warship, aircraft, armored vehicle etc.) must operate acceptably under a wide range of conditions involving different loading configurations; it must maintain war fighting ability and recover quickly and stably after being damaged. The introduction of energy storage for the power system of an electric warship integrated engineering plant (IEP) may increase the availability and survivability of the electrical power under these conditions. Herein, the problem of energy storage control is addressed in terms of maximizing the average performance. A notional medium-voltage dc system is used as the system model in the study. A …

Average-Value Modeling Of Hysteresis Current Control In Power Electronics, Hanling Chen

Theses and Dissertations--Electrical and Computer Engineering

Hysteresis current control has been widely used in power electronics with the advantages of fast dynamic response under parameter, line and load variation and ensured stability. However, a main disadvantage of hysteresis current control is the uncertain and varying switching frequency which makes it difficult to form an average-value model. The changing switching frequency and unspecified switching duty cycle make conventional average-value models based on PWM control difficult to apply directly to converters that are controlled by hysteresis current control.

In this work, a new method for average-value modeling of hysteresis current control in boost converters, three-phase inverters, and brushless …

Design Of System Level Control For A Residential Power Router, Fahad Hossain

Graduate Theses and Dissertations

This thesis presents the overall power flow and load management system for a 2 kW residential power router. The objective is to satisfy the residential load demand with cost savings by managing the energy sources including PV, battery, generator, and grid. The power flow management system algorithm is developed both for grid-connected mode and island mode. This algorithm involves the battery state of charge estimation, available PV power, load demand and electricity grid pricing. The residential load management algorithm is also developed using PV power prediction and load power prediction acquired for a day.¬ A Labview GUI is also developed …

A Prototype Microwave Cavity Control Circuit For Use In Next Generation Free Electron Laser, Josh Thompson, Peter Neal Barrina, Jiayi Jiang, Joe Frisch, Steve Smith, Daniel Van Winkle

STAR Program Research Presentations

One of the current programs at SLAC National Accelerator Laboratory is the Linac Coherent Light Source, or LCLS. Using the existing hardware of the last third of their linear accelerator (or “linac”), SLAC has created one of the most energetic X-ray free electron lasers (or “FEL”). Since 2009, LCLS has used this FEL to perform a wide range of experiments across all sciences, most notably ultrafast filming at the molecular scale. As requests for beam-time with this laser increases, SLAC is purposing a linac upgrade to better match this demand. This upgrade, named LCLS-II, will replace existing copper radio frequency …

An Adaptive Kalman Filter For Voltage Sag Detection In Power Systems, Hisham Odeh Alrawashdeh

Dissertations

The exact values of the noise covariance matrix of the Kalman filter state vector Q and the measured signal noise covariance matrix R must be obtained in order to achieve the optimal performance of the Kalman filter. There have been many techniques and assumptions made to evaluate and compute Q and R. The effects of Q and R are investigated in detail in this dissertation. Based on these investigations, the Kalman filter has been modeled to detect the fundamental signal amplitude variations of power system signals. This technique helps in evaluating voltage sags in power systems.

Two algorithms are …

Multifrequency Averaging In Power Electronic Systems, Fei Pan

Theses and Dissertations--Electrical and Computer Engineering

Power electronic systems have been widely used in the electrical power processing for applications with power levels ranging from less than one watt in battery-operated portable devices to more than megawatts in the converters, inverters and rectifiers of the utility power systems. These systems typically involve the passive elements such as inductors, capacitors, and resistors, the switching electronic components such as IGBTs, MOSFETS, and diodes, and other electronic circuits. Multifrequency averaging is one of the widely used modeling and simulation techniques today for the analysis and design of power electronic systems. This technique is capable of providing the average behavior …

Understanding Vehicular Traffic Behavior From Video: A Survey Of Unsupervised Approaches, Brendan Tran Morris, Mohan Manubhai Trivedi

Electrical & Computer Engineering Faculty Research

Recent emerging trends for automatic behavior analysis and understanding from infrastructure video are reviewed. Research has shifted from high-resolution estimation of vehicle state and instead, pushed machine learning approaches to extract meaningful patterns in aggregates in an unsupervised fashion. These patterns represent priors on observable motion, which can be utilized to describe a scene, answer behavior questions such as where is a vehicle going, how many vehicles are performing the same action, and to detect an abnormal event. The review focuses on two main methods for scene description, trajectory clustering and topic modeling. Example applications that utilize the behavioral modeling …

Design Of An Energy Efficient Virtual End Node Client Using Openadr2.0a And Smap, Kevin Navero

BioResource and Agricultural Engineering

Demand Response (DR) describes the set of actions taken to impose a reduction in electrical loads to stabilize the power grid and decrease costs. It is used when power grid emergencies or extremely high demand and congestion, threaten the electricity supply-demand balance. Automated Demand Response (ADR) describes a web-based control system that triggers DR events automatically by signaling other pre-programmed control systems. This project intends to use the OpenADR2.0 specifications provided by the OpenADR Alliance to construct an open source Virtual End Node (VEN) client to retrieve DR signals. The Simple Measurement and Actuation Profile (sMAP) software is also used …

Voltage Stability Analysis Using Simulated Synchrophasor Measurements, Allan Agatep

Master's Theses

An increase in demand for electric power has forced utility transmission systems to continuously operate under stressed conditions, which are close to instability limits. Operating power systems under such conditions along with inadequate reactive power reserves initiates a sequence of voltage instability points and can ultimately lead to a system voltage collapse. Significant research have been focused on time-synchronized measurements of power systems which can be used to frequently determine the state of a power system and can lead to a more robust protection, control and operation performance. This thesis discusses the applicability of two voltage stability synchrophasor-based indices from …

Modeling And Analysis Of A Dynamic Voltage Regulator, Timothy David Haskell

Master's Theses

Increased government funding and incentives in recent years has led to an increase in the number of grid-tied renewable energy sources as their economic benefits become more renowned. Unfortunately, the outputs of these renewable resources are often highly variable, resulting in undesirable voltage disruptions that are harmful to sensitive loads. In addition to the energy variability of renewable energy sources, random voltage sags, swells and disruptions are already a major issue in power systems. Recent advances in power electronic devices have provided a platform for new solutions to the voltage support problem in power systems. One promising solution is the …

Active Optimal Control Strategies For Increasing The Efficiency Of Photovoltaic Cells, Sharif Aljoaba

Theses and Dissertations--Electrical and Computer Engineering

Energy consumption has increased drastically during the last century. Currently, the worldwide energy consumption is about 17.4 TW and is predicted to reach 25 TW by 2035. Solar energy has emerged as one of the potential renewable energy sources. Since its first physical recognition in 1887 by Adams and Day till nowadays, research in solar energy is continuously developing. This has lead to many achievements and milestones that introduced it as one of the most reliable and sustainable energy sources. Recently, the International Energy Agency declared that solar energy is predicted to be one of the major electricity production energy …

Power Control Of Single-Stage Pv Inverter For Distribution System Volt-Var Optimization, Xiao Liu

Theses and Dissertations--Electrical and Computer Engineering

The output power variability of intermittent renewable sources can cause significant fluctuations in distribution system voltages. A local linear controller that exploits the capability of a photovoltaic inverter to provide both real and reactive power is described. This controller substitutes reactive power for real power when fluctuations in the output of the photovoltaic source are experienced. In this way, the inverter can help mitigate distribution system voltage fluctuations. In order to provide real and reactive to the grid, a three-phase grid-connected single-stage photovoltaic system with maximum power point tracking and power control is described. A method of reducing the current …

Geothermal Injection Well Monitoring, Timothy Rempher

Electrical Engineering

People depend on electricity all over the world. They depend on it for anything from drying their hair to global communications to heating up food. Many methods of power generation exist, each using a different fuel such as nuclear power, natural gas, coal, wind or the sun. This project focuses on a power plant which uses the naturally hot water in the ground to generate electricity. This process of generating power is called “Geothermal.” This project consists of two parts. The first and major part is the design logic of a PLC program that monitors the flow rate of an …

Wireless Sensor Networks And The Internet Of Things, Yingtao Jiang, Lei Zhang, Ling Wang

Electrical & Computer Engineering Faculty Research

It is estimated that mobile internet devices that can act as sensors will outnumber humans this year (2013), and by 2015, there will be about 15 billion internet-connected devices. Related applications are thriving in commercial, civic, and scientific operations that involve sensors, web, and services, leading by both academic societies and industry companies. It is commonly accepted that the next generation of internet is becoming the “Internet of Things (IoT)” which is a worldwide network of interconnected objects and their virtual representations uniquely addressable based on standard communication protocols. Identified by a unique address, any object including computers, mobile phones, …

Tunable Fano Resonances Based On Two-Beam Interference In Microring Resonator, Ting Hu, Ping Yu, Chen Qui, Huiye Qui, Fan Wang, Mei Yang, Xiaoqing Jiang, Hui Yu, Jianyi Yang

Electrical & Computer Engineering Faculty Research

In this paper, a resonant system is demonstrated on silicon-on-insulator wafer to achieve tunable Fano resonances. In this system, the Fano resonance originates from the interference of two beams resonant in the microring resonator. The shapes of the Fano resonances are tunable through controlling the phase difference of the two beams. Both large slope and high extinctionratio (ER) are obtained when the phase difference is 0.5π or 1.5π. Experimental results show that Fano resonances with steep slope and ER over 20 dB are achieved in the whole free spectral range by controlling the microheaters to meet the phase condition.

Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Alexander Paz, Pankaj Maheshwari

Electrical & Computer Engineering Faculty Research

In the context of sustainable transportation systems, previous studies have either focused only on the transportation systemor have not used a methodology that enables the treatment of incomplete, vague, and qualitative information associated with the available data. This study proposes a system of systems (SOS) and a fuzzy logic modeling approach. The SOS includes the Transportation, Activity, and Environment systems. The fuzzy logic modeling approach enables the treatment of the vagueness associated with some of the relevant data. Performance Indices (PIs) are computed for each system using a number of performance measures. The PIs illustrate the aggregated performance of each …

Neural Network Based Control Of Integrated Recycle Heat Exchanger Superheaters In Circulating Fluidized Bed Boilers, David D. Biruk

UNF Graduate Theses and Dissertations

The focus of this thesis is the development and implementation of a neural network model predictive controller to be used for controlling the integrated recycle heat exchanger (Intrex) in a 300MW circulating fluidized bed (CFB) boiler. Discussion of the development of the controller will include data collection and preprocessing, controller design and controller tuning. The controller will be programmed directly into the plant distributed control system (DCS) and does not require the continuous use of any third party software.

The intrexes serve as the loop seal in the CFB as well as intermediate and finishing superheaters. Heat is transferred to …

Smart Wall Plug Design For The Dc House Project, Edward Constant Sibal

Master's Theses

The DC House project at Cal Poly State University faces a challenge of supplying DC voltage to household appliances. Each appliance in the DC House constitutes a DC load that has a unique voltage and power rating, hence the need to develop a smart DC wall plug that will automatically adjust to the operating voltage required by any DC load. This thesis entails a proof of concept design of the smart DC wall plug which can automatically detect an appliance’s voltage rating. The design employs a dc-dc converter in conjunction with a microcontroller to sense load current to properly adjust …

Fault Detection System For Solar Tracking Applications, Hareen Sekhar Illa

Electrical & Computer Engineering Theses & Dissertations

Oil, coal and natural gas reserves are being depleted faster than forecasted due to continued increase in demand for energy sources. We need, therefore, to develop renewable energy sources, such as solar, wind, biomass, geothermal, hydro power and tidal energy. In spite of having very high potential, harvesting solar energy has been a challenge because of the relatively low efficiency of solar cells. In the past few years different methods have been developed to increase the efficiency of the photovoltaic (PV) system: (I) improve the efficiency of solar cells (ill use a solar tracking system to increase the received solar …

A Proposed Control Solution For The Cal Poly Wind Energy Capture System, Kent R. Burnett

Master's Theses

The focus of this thesis is to research, analyze, and design a reliable and economical control system for the Cal Poly Wind Energy Capture System (WECS). A dynamic permanent magnet generator model is adopted from [1] and [2] and combined with an existing wind turbine model to create a non-linear time varying model in MATLAB. The model is then used to analyze potentially harmful electrical disturbances, and to define safe operating limits for the WECS. An optimal operating point controller utilizing a PID speed loop is designed with combined optimization criteria and the final controller design …

Monitoring And Regression Based Modelling Of End Winding Vibration In Large Synchronous Generators., David Shally

Masters

This research project was set up to monitor, on an ongoing basis, the condition of the end windings and their support structures of a 288 MVA 2-pole synchronous generator with a known end winding vibration problem Excessive vibration at the end windings was caused by the natural frequencies of individual end bars (local) and of the entire end winding structure (global) being at or close to the magnetic forcing frequency of 100 Hz. Resonant vibration such as this has been a cause of major failures in machines of the same type in the past, resulting in significant down time ranging …

A Robust Decentralized Load Frequency Controller For Interconnected Power Systems, Lili Dong, Yao Zhang, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

A novel design of a robust decentralized load frequency control (LFC) algorithm is proposed for an inter-connected three-area power system, for the purpose of regulating area control error (ACE) in the presence of system uncertainties and external disturbances. The design is based on the concept of active disturbance rejection control (ADRC). Estimating and mitigating the total effect of various uncertainties in real time, ADRC is particularly effective against a wide range of parameter variations, model uncertainties, and large disturbances. Furthermore, with only two tuning parameters, the controller provides a simple and easy-to-use solution to complex engineering problems in practice. Here, …