Engineering Commons^™

Improvements Of Hybrid Ac/Dc House Prototype, Arden Abude

Electrical Engineering

This is an iteration from previous designs of the Hybrid AC/DC House with a systematic addition of a portable AC power supply unit. This iteration for the Hybrid AC/DC House is an innovation of independence for sustainable housing solutions. It will serve as an alternative for rural communities needing power to rely on self-sustainable microgrids rather than large-scale AC electric grids. The addition of a portable AC power supply would allow the microgrid to remove its reliance on AC power from the larger grid and would elevate the system to complete energy independence. The microgrid has DC power generated from …

Hybrid Wall Outlet For Ac Or Dc Power Delivery, Garrett Knoller, Kerr Allan, Greg Perini

Electrical Engineering

The goal of this project is to develop hybrid DC and AC wall outlets for an efficient, flexible power interface. A DC plug standard is also proposed to allow DC devices to be safely powered by the outlet with the correct DC voltage for each device. The primary objective is to create a power outlet compatible with the proposed DC plug as well as NEMA 5-15 AC plugs, enabling the same outlet to power both types of load as needed. The outlet is intended for buildings and systems transitioning to an isolated DC grid to encourage DC development and adoption. …

Design Of Hybrid Inverters Using Wideband Gap Semiconductors For Microgrid Application, Luca Gacy

Electronic Theses and Dissertations

As the world becomes more reliant on renewable energy sources such as solar and wind power, the need for high efficiency high power inverters connected to homes is more relevant than ever. Connecting these renewable energy sources (RES) coupled with an energy storage system (ESS) to the grid through a hybrid inverter, with the highest efficiency and grid stability, is quickly becoming a necessity for the near future. This thesis explores the integration of wide band gap semiconductors for the power stage in these systems, along with the analysis of hybrid inverter topologies and structures. The goal of this thesis …

Microgrid Energy Storage Branch, Evan Luu, Jeffrey Shieh

Electrical Engineering

The microgrid is the future for the electrical utility system. Because of this, future power engineers need to be well-versed in this topic when they go into industry. Cal Poly has created a microgrid laboratory for this very purpose. However, it is missing its battery based energy storage branch. Due to safety concerns, a traditional chemical battery is not suitable for student use. In order to maintain Cal Poly’s learn-by-doing approach, an alternative solution must be implemented. A regenerative power supply meets the criteria for student use. It is capable of simulating the sinking and sourcing capabilities of a battery …

Dc Microgrid Fault Detection Using Multiresolution Analysis Of Traveling Waves, Rudy Montoya

Mechanical Engineering ETDs

Fast detection and isolation of faults in a DC microgrid is of particular importance. Fast tripping protection (i) increases the lifetime of power electronics (PE) switches by avoiding high fault current magnitudes and (ii) enhances the controllability of PE converters. This thesis proposes a traveling wave (TW) based scheme for fast tripping protection of DC microgrids. The proposed scheme utilizes a discrete wavelet transform (DWT) to calculate the high-frequency components of DC fault currents. Multiresolution analysis (MRA) using DWT is utilized to detect TW components for different frequency ranges. The Parseval energy calculated from the MRA coefficients are then used …

Modeling Of Inverter-Based Microgrid For Small-Signal And Large-Signal Stability Analysis, Vishal Verma

Graduate Theses, Dissertations, and Problem Reports

Integration of inverter-based resources (IBRs) such as solar photovoltaic, wind, and battery storage, is both a boon and a bane for electric power systems. On one hand, IBRs have helped in making electrical energy a clean (carbon-free) source of energy. On other hand, the dynamics of IBRs have changed the way power system studies have been carried out. With the advantages IBRs offer over conventional resources, it is assumed that a small distribution power system (microgrid) will have a 100% IBRs penetration in the future. Such a microgrid can operate in grid-connected mode or in an islanded mode. Both modes …

Split-Horizon Dual-Stage Dispatch Scheme For A Standalone Microgrid, Aslam Amir

Theses

The advent of microgrids has prompted plenty of studies into its design, control, protection, and implementation, with several operational as well as pilot systems being commissioned worldwide. This necessitates the development of hardware and software for the Energy Management System, the supervisory controller in a microgrid. Hence, this thesis provides a novel dual-stage dispatch scheme for the Energy Management System of a Standalone microgrid by “splitting” the dispatch time horizon into four equal quarters to facilitate better usage of power forecast accuracies. The two stages include Unit Commitment/Scheduling and Economic Dispatch for the dispatchable Distributed Energy Resources based on renewable …

Development Of A Converter-Based Testing Platform And Battery Energy Storage System (Bess) Emulator For Microgrid Controller Function Evaluation, Dingrui Li

Masters Theses

The microgrid has attracted increasing research attention in the last two decades. Due to the development of renewable energy resources and power electronics technologies, the future microgrid will trend to be smarter and more complicated. The microgrid controller performs a critical role in the microgrid operation, which will also become more and more sophisticated to support the future microgrid. Before final field deployment and test, the evaluation and testing of the controller is an indispensable step in the controller development, which requires a proper testing platform.

However, existing simulation-based platforms have issues with potential numerical oscillation and may require huge …

Energy Management And Control Of Smart Power Distribution Systems, Eric Galvan

Open Access Theses & Dissertations

With the development of distributed energy resources (DERs) and advancements in technology, microgrids (MGs) appear primed to become an even more integral part of the future distribution grid. In this transition to the smart power grid of the future, MGs must be properly managed and controlled to allow efficient integration of DERs. Over the past years, there has been rapid adoption of roof-top solar photovoltaic (PV) and battery electric vehicles (BEVs). Although roof-top solar PV and BEVs can provide environmental benefits (e.g., reduction of emissions), they also create various challenges for power system operators. For example, roof-top solar PV generation …

Control Strategy For A Small-Scale Microgrid Based On Battery Energy Storage System-Virtual Synchronous Generator (Bess-Vsg), Wei Gao

Electronic Theses and Dissertations

As one of widely deployed renewable energy resources, PV power is playing a very important role in microgrids today. It has advantages such as making the best of natural solar energy and being friendly to our environment. In this thesis, solar PV based microgrid is studied using modeling and simulation. Microgrid can run in either grid-connected-mode or islanded-mode. However, there are also some disadvantages for solar power. For solar panel, its output is influenced by weather conditions such as illumination intensity and temperature. In addition, during the control process of grid-connected mode, it is hard to guarantee its output power …

Microgrid Reliability Evaluation Based On Condition-Dependent Failure Models Of Power Electronic Devices, Qi Li

Theses and Dissertations

Microgrid, a distributed energy system consisting of distributed energy and loads, aims to ensure reliable and affordable energy security in urban and rural communities. With the growing global energy need and the emerging threat of climate change, green renewable energy is becoming a new favorite in the field of power generation. Microgrids have received wide spread attention and application for their minimizing carbon dioxide and greenhouse gas emissions. Microgrids do so by maximizing clean local energy generation as well

as reducing the stress of the transmission and distribution system.

With the use of renewable energy, the reliability performance of microgrids …

Realization Of A High Power Microgrid Based On Voltage Source Converters, Yusi Liu

Graduate Theses and Dissertations

Microgrid concepts are gradually becoming more popular because they are expected to interface with renewable energies, increase end users’ reliability and resiliency, and promote seamless integration of distributed generators (DG) and energy storage units [1]. Most units are connected through power electronics interfaces, such as ac-dc, dc-dc, and dc-ac converters. The converter design and control are critical to the stability and efficiency of a microgrid.

A microgrid may operate in either gird connected mode or islanded mode [1]. In terms of stability, the grid connected mode is less challenging compared to the islanded mode of operation due to the nearly …

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 …

Virtual Droop Control Framework And Stability Analyses For Microgrids With High Penetration Of Renewables, Ashishkumar Kanubhai Solanki

Theses and Dissertations

Microgrids can provide the most promising means of integrating large amounts of distributed sources into the power grid and can supply reliable power to critical loads. However, managing distributed sources and loads within a microgrid during island and grid-tie modes and during transitions is a challenge. Stable operation of a microgrid is a concern specifically during the starting of motor loads, switching of large loads, and in presence of high penetration of renewable resources. Hence, a generalized control framework is required to regulate microgrid voltage and frequency, maintain power quality, manage Distributed Generations (DG) and ensure microgrid stability. Several control …

Microgrid Modeling And Grid Interconnection Studies, Hira Amna Saleem

Masters Theses

The demand for renewable energies and their integration to the grid has become more pressing than ever before due to the various reasons including increasing population energy demand, depleting fossil fuels, increasing atmospheric population, etc. Thus the vision of a sustainable future requires easy and reliable integration of renewable distributed generators to the grid. This master’s thesis studies the dynamics of distributed generators when they are connected with the main grid. Simulink MATLAB is used for the design and simulations of this system. Three distributed generators are used in this system: Photo-voltaic converter, Fuel cell and diesel generator. The control …

Modeling, Analyses And Assessment Of Microgrids Considering High Renewable Energy Penetration, Qiang Fu

Theses and Dissertations

Microgrids are receiving attention due to the increasing need to integrate distributed generations and to ensure power quality and provide energy surety to the customers. Since renewables need to be in the mix for energy surety, a high renewable-energy penetrated microgrid is analyzed in this paper. The standard IEEE 34 bus distribution feeder is adapted and managed as a microgrid by adding distributed generation and load profiles. The 25kV system parameters are scaled down to 12kV and renewable sources including solar PV and wind turbines, an energy storage system, and a natural gas generator have been added to the 34-bus …

Neural Network Based Microgrid Voltage Control, Chun-Ju Huang

Theses and Dissertations

The primary purpose of this study is to improve the voltage profile of Microgrid using the neural network algorithm. Neural networks have been successfully used for character recognition, image compression, and stock market prediction, but there is no directly application related to controlling distributed generations of Microgrid. For this reason the author decided to investigate further applications, with the aim of controlling diesel generator outputs.

Firstly, this thesis examines the neural network algorithm that can be utilized for alleviating voltage issues of Microgrid and presents the results. MATLAT and PSCAD are used for training neural network and simulating the Microgrid …

Cooperative Control And Advanced Management Of Distributed Generators In A Smart Grid, Ali Maknouninejad

Electronic Theses and Dissertations

Smart grid is more than just the smart meters. The future smart grids are expected to include a high penetration of distributed generations (DGs), most of which will consist of renewable energy sources, such as solar or wind energy. It is believed that the high penetration of DGs will result in the reduction of power losses, voltage profile improvement, meeting future load demand, and optimizing the use of non-conventional energy sources. However, more serious problems will arise if a decent control mechanism is not exploited. An improperly managed high PV penetration may cause voltage profile disturbance, conflict with conventional network …

Fault Protection In Dc Distribution Systems Via Coordinated Control Of Power Supply Converters And Bus Tie Switches, Pietro Cairoli

Theses and Dissertations

A new fault protection method responds to the current needs of emerging dc power distribution systems by coordinating electronic power converters and mechanical contactors to rapidly isolate short circuit faults while maintaining continuity of power to loads. This work is important because the increasing performance, higher efficiency, and decreasing cost of electronic power converters have spurred a rediscovery and proliferation of dc power distribution systems. Although dc distribution offers advantages such as higher transmission efficiency, higher power density, higher reliability, and ease of interfacing asynchronous sources, enthusiasm for adopting dc technologies suffers from widespread concern over the means to protect …

Coordinated Control Of Power Electronic Converters In An Autonomous Microgrid, Gholamreza Dehnavi

Theses and Dissertations

Advances in power electronics and generation technologies have increased the viability of distributed generation systems. A microgrid is a special category of distributed generation systems that is distinguished by its size and the ability to operate independently as an islanded system. As long as a microgrid is connected to a large grid, quality of the voltage is supported by the main grid and each power source connected to the microgrid generates independently. In contrast, in the islanded operation of microgrids and in electrical islands such as shipboard distribution systems, dynamics are strongly dependent on the connected sources and on the …