Engineering Commons^™

Data-Driven Approaches For Enhancing Power Grid Reliability, Behrouz Sohrabi

Electronic Theses and Dissertations

This thesis explores the transformative potential of data-driven approaches in addressing key operational and reliability issues in power systems. The first part of this thesis addresses a prevalent problem in power distribution networks: the accurate identification of load phases. This study develops a data-driven model leveraging consumption measurements from smart meters and corresponding substation data to reconstruct topology information in low-voltage distribution networks. The proposed model is extensively tested using a dataset with more than 5,000 real load profiles, demonstrating satisfactory performance for large-scale networks. The second part of the thesis pivots to a crucial safety concern: the risk and …

Measurement-Based Monitoring And Control In Power Systems With High Renewable Penetrations, Chengwen Zhang

Doctoral Dissertations

Power systems are experiencing rapid changes in their generation mixes because of the increasing integration of inverter-based resources (IBRs) and the retirement of traditional generations. This opens opportunities for a cleaner energy outlook but also poses challenges to the safe operation of the power networks. Enhanced monitoring and control based on the increasingly available measurements are essential in assisting stable operation and effective planning for these evolving systems.

First, awareness of the evolving dynamic characteristics is quintessential for secure operation and corrective planning. A quantified monitoring study that keeps track of the inertial response and primary frequency response is conducted …

Examining Direct Load Control Within Demand Response Programs, Maria Bonina Zimath

Honors Undergraduate Theses

The power system is a complex entity with unique plant designs, control systems, and market strategies. For many years, engineers have developed advanced technology to keep the grid efficient and balanced. With the rise of renewable sources, some new technology and programs must be developed to keep the quality of the power system. Unlike traditional power plants, renewable energy is highly dependent on environmental factors, such as sunlight and wind, meaning the generation depends on an unpredictable source of fuel. As the grid moves to more sustainable sources, the power market faces a growing challenge of less control over the …

An Efficient Ar Model-Based Method For The Detection Of Forced Oscillations In Power Networks: Implementation And Analysis, Maria Waleska Suarez

Graduate Theses, Dissertations, and Problem Reports

An active research topic is the detection of various oscillations that may lead to instability and potential disruption in the operation of a power network. Forced Oscillations (FOs) play a unique role in power system stability among various oscillations. They are perturbances that change the system’s state and are caused for many reasons, including but not limited to persistent load changes and oscillatory load or generation, fault, triplane, and other mechanical anomalies. These factors can hugely affect the power grid by either increasing or decreasing the amplitude, causing corrupt modes leading to blackouts, affecting the equipment involved, delivering poor power …

Power System Stability Assessment With Supervised Machine Learning, Mirka Mandich

Masters Theses

Power system stability assessment has become an important area of research due to the increased penetration of photovoltaics (PV) in modern power systems. This work explores how supervised machine learning can be used to assess power system stability for the Western Electricity Coordinating Council (WECC) service region as part of the Data-driven Security Assessment for the Multi-Timescale Integrated Dynamics and Scheduling for Solar (MIDAS) project. Data-driven methods offer to improve power flow scheduling through machine learning prediction, enabling better energy resource management and reducing demand on real-time time-domain simulations. Frequency, transient, and small signal stability datasets were created using the …

Impact Of Wind Generation On Transmission Voltage Support During Weak Grid, Yugo Isogai

Electrical Engineering Undergraduate Honors Theses

Today, there are concerns about the effects of high wind penetration on electric power system operations. This is due to the more distributed nature of wind turbine generation and the corresponding multi-path power flows on the electric power transmission grid. In particular, the higher line impendences associated with inverter-based wind generation results in larger voltage fluctuation under varying load. This may results in conditions where even after a fault condition has been cleared, the transmission system voltages may not recover. Therefore, this paper concentrates on the impact of weak grid condition for voltage instability. To approach it, a 6-bus system …

Voltage Security Optimization For Power Transmission Systems, Tamer Ibrahim

Dissertations and Theses

This project proposes an optimization approach for day-ahead reactive power planning to ensure voltage security in transmission networks. The problem is formulated as a voltage-secure multi-period optimal reactive power dispatch (MP-ORPD) problem. The optimization approach searches for optimal set-points of dynamic and static reactive power (var) resources. Specifically, the output includes set-points for switching shunts, transformer taps, and voltage magnitudes at the regulated buses. The primary goal is to maximize the dynamic reactive power reserve of the system, by minimizing the reactive power supplied by synchronous generators. The secondary goal is to minimize changes in the settings of switching shunts …

Aggregated Der Management In Advanced Distribution Grids, Mohsen Mahoor

Electronic Theses and Dissertations

Evolution of modern power systems are more distinct in distribution grids, where the growing integration of microgrids as well as distributed energy resources (DERs), including renewable energy resources, electric vehicles (EVs), and energy storage, poses new challenges and opportunities to grid management and operation. Rapid growth of distribution automation as well as equipment monitoring technologies in the distribution grids further offer new opportunities for distribution asset management. The idea of aggregated DERs is proposed as a remedy to streamline management and operation of advanced distribution grids, as discussed under three subjects in this dissertation. The first subject matter focuses on …

Matlab Gui Based Educational Simulation Tool Box For Power Analysis, Tharuka Senevirathne

All Graduate Theses, Dissertations, and Other Capstone Projects

One of the most important and complex tasks in power engineering is the analysis of power systems under fault conditions. The detection and analysis of these faults are important to guarantee that the dependability and stability of the power system does not decline as a result of a critical event such as a fault. This thesis will conduct research on how a power system under fault conditions behaves and will examine the various scenarios of faults such as three-phase, single line-to-ground, line-to-line, and double line-to-ground faults. A simplified method based on symmetrical components is used to construct the mathematical models …

Application Of Droop Control And Synchronization For Single-Phase Inverters In Ac Microgrid Integration, Shuai Yang

All Graduate Theses, Dissertations, and Other Capstone Projects

With the increasing requirements on environment-friendly and sustainable clean energy [1], people have paid more attention to renewable energy around the world in the past few decades. As a result, power systems have undergone a paradigm shift from centralized generation to distributed generation. Smart grids, which are a combination of power systems and communication networks, were proposed to allow power systems to meet future challenges. In smart grids, especially in AC microgrids, converters play an important role in many areas including microgrid integration, uninterrupted power supply, and flexible alternating current transmission systems. The inverter is a power conversion device [2] …

Advanced Fault Area Identification And Fault Location For Transmission And Distribution Systems, Wen Fan

Theses and Dissertations--Electrical and Computer Engineering

Fault location reveals the exact information needed for utility crews to timely and promptly perform maintenance and system restoration. Therefore, accurate fault location is a key function in reducing outage time and enhancing power system reliability.

Modern power systems are witnessing a trend of integrating more distributed generations (DG) into the grid. DG power outputs may be intermittent and can no longer be treated as constants in fault location method development. DG modeling is also difficult for fault location purpose. Moreover, most existing fault location methods are not applicable to simultaneous faults. To solve the challenges, this dissertation proposes three …

Grid-Tied Solar System, Virginia Yan

Electrical Engineering

Distribution level solar energy generation has gained importance and popularity, because it helps create a sustainable electricity system while reducing the harmful environmental impacts our current power systems have. This project proposes an alternative energy source, a laboratory-scale grid-connected photovoltaic system. A KC120-1 solar panel produces 120 Watts maximum. A grid-tied solar power inverter does DC-to-AC conversion and minimizes energy transfer losses. The inverter also has an anti-islanding feature, which senses a power outage and prevents back-feeding through isolating the circuit. The circuit breakers isolate electrical components and protect the circuit. Schweitzer Engineering Laboratories SEL-751 feeder protection relay and SEL-735 …

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 …

Wide-Area Control Schemes To Improve Small Signal Stability In Power Systems, Meimanat Mahmoudi

Doctoral Dissertations

One of the main concerns for the secure and reliable operation of power systems is the small signal stability problem. In the complex and highly interconnected structure of future power systems, relying solely on operator responses and conventional controls cannot assure reliability. Therefore, there is a need for advanced Wide-Area Control Schemes (WACS) that can automatically respond to degradation of reliability in the system.

The main objective of this dissertation is to address two key challenges regarding the design and implementation of wide-area control schemes for damping inter-area oscillations. First is the high communication cost associated with optimal centralized control …

Microgrid Protection Student Laboratory, Ian Hellman-Wylie, Joey Navarro

Electrical Engineering

To better prepare students for careers in the electric power industry, specifically in the discipline of power system protection, the Electrical Engineering Department at Cal Poly San Luis Obispo proposed an initiative calling for the creation of new laboratory curriculum that uses microprocessor-based relays to give students hands-on experience in the application of protection theory. This report describes the creation of a system that meets this need by providing a laboratory-scale power system that demonstrates the use of common protective relays and protection schemes. This system provides a platform for laboratory coursework using protective relays for transmission line, transformer, and …

Bi-Level Optimization Considering Uncertainties Of Wind Power And Demand Response, Xin Fang

Doctoral Dissertations

Recently, world-wide power systems have been undergone a paradigm change with increasing penetration of renewable energy. The renewable energy is clean with low operation cost while subject to significant variability and uncertainty. Therefore, integration of renewables presents various challenges in power systems. Meanwhile, to offset the uncertainty from renewables, demand response (DR) has gained considerable research interests because of DR’s flexibility to mitigate the uncertainty from renewables. In this dissertation, various power system problems using bi-level optimization are investigated considering the uncertainties from wind power and demand response.

In power system planning, reactive power planning (RPP) under high-penetration wind power …

Model Development And Validation For Wind Generation Transmission Systems, Mahmood Shihadeh Saadeh

Graduate Theses and Dissertations

In this research a new benchmark system is proposed for wind energy transmission systems. New model development, validation, and calibration methods for power transmission systems are proposed and implemented as well. First, a model reduction criteria is chosen based on electrical interconnection and geographical information. Model development is then done using reduction techniques on an operation model provided by a transmission operator based on the chosen criteria. Then model validation is performed using actual PMU synchrophasor measurements provided by a utility company. The model development and validation process ensures the accuracy of the developed model and makes for a realistic …

Saturable Reactor For Power Flow Control In Electric Transmission Systems: Modeling And System Impact Study, Marcus Aaron Young Ii

Doctoral Dissertations

A Saturable Reactor for Power Flow Control (SRPFC) is a novel application of a concept well known to electronics and power electronics engineers that provides continuous modulation of line reactance by controlling the magnetization in a ferromagnetic core. The novelty of the SRPFC is the target application, which is power flow control in meshed electric power networks. Modulation of the line impedance occurs by altering the current in a DC winding to control the magnetization of the ferromagnetic core, thereby varying the reactance of the AC winding. The deployment of power system equipment, like SRPFC, requires careful planning and study …

Motor Protection Lab Experiment Using Sel-710, Ozro Corulli

Electrical Engineering

Advancements in microprocessor based relay technology for power protection applications provide quicker response times and new methods of mitigation. This project develops a lab experiment for Cal Poly class EE444 - Power Systems Laboratory based on the Schweitzer SEL-710 motor protection relay. Learning objectives for this lab include relay setup, programming, and protection schemes for the following conditions: undervoltage, loss of phase, fault, locked rotor, and thermal overload. Today, utility companies across the globe use SEL relays for primary system protection, putting engineers familiar with their operation in high demand.

High Order Contingency Selection Using Particle Swarm Optimization And Tabu Search, Ashwini Chegu

Masters Theses

There is a growing interest in investigating the high order contingency events that may result in large blackouts, which have been a great concern for power grid secure operation. The actual number of high order contingency is too huge for operators and planner to apply a brute-force enumerative analysis. This thesis presents a heuristic searching method based on particle swarm optimization (PSO) and tabu search to select severe high order contingencies. The original PSO algorithm gives an intelligent strategy to search the feasible solution space, but tends to find the best solution only. The proposed method combines the original PSO …