Power and Energy Commons^™

Unbalanced Current Static Compensator, Manuel Antonio Sanchez Tejada

Graduate Theses and Dissertations

The objective of this thesis is to present and evaluate a solution to the unbalanced current issue that can be found in three-phase electrical power grids. The solution is named unbalanced current static compensator (UCSC) and has the goal of balancing the currents at the source in order to mitigate adverse issues such as of negative- and zero-sequence currents that are generated by three-phase current unbalances.

The solution topology consists of three single-phase H-bridge converters that are controlled through an algorithm working in the d-q frame of reference. The algorithm is divided in three different stages: the phase synchronization and …

Smart Wall Outlet Design And Implementation For The Dc House Project, Kevin Roy Mendoza

Master's Theses

Most everyday AC appliances are designed to operate off of 120V coming from the wall outlet in our homes. This voltage is a standard set from our established infrastructure. Unlike AC devices, DC devices do not have any set standard of voltage they all will run off of. This presents a problem for the DC house as the various loads that will be used will have different required input voltages. One set voltage for a wall outlet will not suffice for the DC House. This Smart Wall Outlet is designed with a DC-DC converter that will have its output voltage …

Human-Powered Swing Generator, Danny Cai, Timothy Lai, Brandon Wong

Electrical Engineering

Many developing countries lack sufficient resources to provide enough electricity for every family to live with a satisfying level of comfort and convenience. Our project proposes a solution that provides families with an alternative access to electricity using a playground swing. This project addresses the design and construction of the Human-Powered Swing Generator, which converts mechanical energy to electrical energy for charging a battery. The charged battery serves as a source of DC energy for potential DC purposes, such as charging a cell phone.

Local Digital Control Of Power Electronic Converters In A Dc Microgrid Based On A-Priori Derivation Of Switching Surfaces, Bibaswan Banerjee

Dissertations, Master's Theses and Master's Reports - Open

In power electronic basedmicrogrids, the computational requirements needed to implement an optimized online control strategy can be prohibitive. The work presented in this dissertation proposes a generalized method of derivation of geometric manifolds in a dc microgrid that is based on the a-priori computation of the optimal reactions and trajectories for classes of events in a dc microgrid. The proposed states are the stored energies in all the energy storage elements of the dc microgrid and power flowing into them. It is anticipated that calculating a large enough set of dissimilar transient scenarios will also span many scenarios not specifically …

Optimization Of Nonlinear Switch Cells For Switching Converters, Bradley Alan Reese

Graduate Theses and Dissertations

Switch cells consist of an array of power switches and passive components which can replace the main switches alone in many power topologies, allowing reduced switching loss without altering the power topology directly. This thesis discusses the development of a switch cell topology that utilizes a saturable resonant inductor to reduce the size and power loss of the cell. Additionally, the cell transfers energy stored in the inductor into a capacitor for efficient energy storage during the cell's conduction region. This energy is then transferred back to the system when the cell turns off, thus reducing the total switching energy.

Efficiency Performance Improvement Using Parallel Dc-Dc Converters With A Digital Controller, Daniel Forbes

Master's Theses

A system to improve efficiency performance of a DC-DC converter is simulated and built. The proposed system combines multiple DC-DC converters in parallel and implements a digital control scheme and load-share controller. A model of the system is developed in MATLAB Simulink and the model demonstrates the improved converter’s efficiency particularly at low load conditions. This simulation is then designed into a hardware system running three DC-DC converters in parallel, controlled by a microcontroller and a load-share controller. The hardware also confirms the simulation results, although some hardware refinements are evident as simulation results are superior. The system is designed …

Imu Integration To The Cal Poly Spacecraft Attitude Dynamics Simulator Power System, Wayland Chan

Electrical Engineering

The Cal Poly Spacecraft Attitude Dynamics Simulator mimics the rotation dynamics of a spacecraft in orbit and acts as a test bed for spacecraft attitude control system development and demonstration. Prior to this project, the simulator measured its attitude dynamics from a total of seven sensors mounted on to the platform, including three micro-electromechanical system (MEMs) gyroscopes, and four motor encoders. This project entails the installation of an LN-200 high performance gyroscope, which will provide a greater measure of accuracy. The goal of this project is to design a power circuit that will integrate the LN-200 inertial measurement unit onto …

Design And Analysis Of A Wind Energy Harvesting Circuit Using Piezoelectric Polymers, Jameson J. Thornton

Master's Theses

This thesis investigates a relatively new method for harvesting wind energy by using flexible piezoelectric polymers with additional sails to increase their ability to harvest wind energy. This paper also introduces a new topology deemed the “stacked buck” that allows for multiple inputs to a system with a single output. Derivations and analysis detail the workings of the “stacked buck” with a laboratory test to show a working model. This paper also reports another experiment done in a wind tunnel to analyze the capability of the piezoelectric polymers as sources to the “stacked buck” topology with measurements of the power …

Modular Electronic Load, Jason March

Electrical Engineering

This project entails the design and development of a modular electronic load. The cost and simplicity of the design are considered such that it can be reproduced in-house to replace whenever possible resistor box for load testing of any analog circuits but more specifically power electronic circuits.

The design process as well as the hardware development is explained in details in this report. Results from hardware testing are also provided.

An Expandable Micromotor Dc Drive System, Michael Ruelan, Justin Gragg

Electrical Engineering

This report documents the design phases and fabrication of an expandable micro-motor DC drive system. This project illustrates that a flexible range of output power demands can be met from a small DC micro-motor drive unit with the use of power electronics.

In this project miniature DC micromotor drives, each capable of drawing up to 5.5 amps rated current (5 amps due to the utilization of a 5 amp fuse), were designed as card inserts that can be conveniently inserted in parallel in to a cardholder within the console. The “insert” feature allowed our console to successfully draw up to …

High Voltage Resonant Self-Tracking Current-Fed Converter, Scott Logan Mcclusky

Master's Theses

High voltage power supply design presents unique requirements, combining safety, controllability, high performance, and high efficiencies. A new Resonant Self-Tracking Current-Fed Converter (RST-CFC) is investigated as a proof-of-concept of a high voltage power supply particularly for an X-ray system. These systems require fast voltage rise times and low ripple to yield a clear image.

The proposed converter implements high-frequency resonance among discrete components and transformer parasitics to achieve high voltage gain, and the self-tracking nature ensures operation at maximum gain while power switches achieve zero-voltage switching across the full load range. This converter exhibits an inherent indefinite short-circuit capability. Theoretical …

Harmonic Analysis Of A Static Var Compensated Mixed Load System, James David Ruckdaschel

Master's Theses

As power electronic based controllers and loads become more prevalent in power systems, there is a growing concern about how the harmonics generated by these controllers and loads affect the power quality of the system. One widely used power electronic based load is the Variable Frequency Drive (VFDs) used to vary the speed of an induction motor; whereas a common example of a power electronic based controller used in power systems is the Static VAR Compensator (SVC) for improving a system’s power factor. In this thesis, the harmonic content and overall performance of a system including both a VFD and …