Generating abundant, renewable energy from Earth’s oceans is an attractive option for meeting increasing energy demand. Marine renewable energy also comes with the variability of renewable sources, which impact the reliability and power quality of the electrical grid. On a transmission-level, this dissertation looks at ensuring reliability of the power...
This work addresses the application of Nonlinear Model Predictive Control (NMPC) to a class of ocean wave energy conversion systems in which the cost functional is not in a standard quadratic form, and the WEC model includes the nonlinear effects, such as the hydrodynamic viscous drag. The NMPC implementation is...
Ocean Wave Energy Converters (WECs) are of interest around the globe as global economies begin to shift their interest to renewable forms of energy. However, the devices are costly to construct–a quality that can be relieved through proper modeling, control, and implementation. This paper presents the numerical and hybrid simulation...
The electrical grid of the Western Interconnection is vulnerable to earthquake damage, especially large-magnitude megathrust events, due to the unique seismic profile of the region. However, the size of the Western Interconnection makes it difficult to model seismic failure in electrical substations to the level of detail necessary to improve...
In a power system, operators maintain voltage stability through adequate reactive reserves. Maintaining and accessing an efficient allocation of reactive reserves is prohibitively complex because of reactive line losses, the variety of reactive resources, and either limited or variable reactive outputs from renewable sources. By clustering the system into smaller...
Data acquisition (DAQ) systems are a necessary component for products whose outcomes depend on collected information throughout its operation. Current systems are directed towards users utilizing custom hardware, software, and requiring its user to have high-level skills in coding and system setup; but with the increasing interest in renewable energy,...
As the sources of our electricity shift from centralized and carbon emitting, to a portfolio of distributed, clean-energy sources, the wave energy converter (WEC) has become a topic of exploration and development for providing coastal communities electric power. Part of this trend has included an effort to create open source...
The Pacific Northwest is part of the "Ring of Fire," which is well-known for heavy seismic activity. Numerous active faults in the area have encouraged electric grid managers in the region to more deeply contemplate and proactively intervene to support grid resilience. This research introduces Monte Carlo (MC) based power...
Ocean waves provide a promising source of renewable energy for the North American electric grid. However, ideal control of wave energy converters (WECs) requires perfect forecasting of future wave conditions, and waves can be unpredictable. This paper presents a comparison of three different prediction methods and analyzes their performance in...
This design of a Grid Friendly Electric Hot Water Heater Thermostat was built for the Electrical and Computer Engineering Senior Design course, ECE44x. The design enables hot water heaters to respond to imbalances in the grid seen through deviations from standard grid frequency by varying the power output to the...
Electricity is at the center of attention as today many essential systems (water, gas, communications, and the internet for example) and infrastructures depend on its continuity for their smooth functioning. On the other hand, electricity power networks have developed and became large, and highly complex technical systems, geographically extended, requiring...
Model Predictive Control (MPC) has previously been investigated on ocean waveenergy converters (WEC) to improve the amount of power captured, while respectingthe system constraints. Previous research done in the same area, focused onbuilding a control scheme by using the knowledge of the past & current statesof the system and predicting...
When the term renewable energy is mentioned in a conversation, wind, solar, and hydro energy typically come to mind. However, there is one major resource that has remained mostly untapped: wave energy. Wind and solar power technologies are well established around the world but they cannot generate electricity all the...
Load modeling that can accurately represent the dynamic behavior of generators and loads is important in the operation and planning of transmission and distribution systems. Yet, it is a complex subject in power system research communities and electric utilities. The composition of the end-use loads is changing continually based on...
Wave energy converters (WECs) are a broad class of emerging technology that converts hydrokinetic energy into some other useful form, such as electricity. The last stage in this transformation, the power take-off (PTO) subsystem, is often not experimentally evaluated until half-way through the recommended development process. This delay in evaluation...
Hydropower is the one of the oldest renewable energy technologies and is wrongly thought of today as having little room to grow. The opportunity for new hydropower capacity is immense through both technology advancement and run-of-river new stream reach projects. Despite the age of hydropower, a divide in opinion is...
Recently, there has been peaked interest in developing high energy producing and optimized power take-off topologies for Wave Energy Converters (WEC). As large as the potential of the oceans may seem, harnessing that energy and effectively converting it to electricity in significant amounts is a challenge. Currently, there are no...
The National Conference of State Legislatures NCSL declares that 29 states have
been active in adopting and increasing renewable portfolio standards. Present
renewable portfolio standards require utilities to increase integration of renewable
energy sources such as photovoltaic (PV). The increased penetration of PV systems
is expected to destabilize the power...
Recent opportunities for new hydropower generation in the United States have often been in non-powered dams and run-of-river type flows occurring in low-impact natural areas and unregulated conduits. At the same time, a changing water resource paradigm is challenging some existing generation in drought stricken areas where supply reservoirs behind...
Synchrophasor technology has gained great momentum with the widely adopted concept of smart grids in power systems at transmission and generation level. This has led to an improved state estimation of a power system with the advent of Phasor Measurement Units (PMU). PMUs contribute in providing real-time information about the...
The objective of the work presented herein is the development of the extended Kalman filter for nonlinear system modeling. A standard Kalman filter is a well-known filter for estimating the state of a system, assuming the system is linear and it has a Gaussian distribution in its noise. In reality,...
Recent blackout events consistently show that a variety of mechanisms are involved in cascading outages. These cascading mechanisms are irregularly modeled and validated within the existing literature and industry practices. Understanding the relative significance of these different mechanisms is important for choosing which one(s) needs to be modeled for specific...
Permanent magnet synchronous machines (PMSMs) are widely used in electric vehicles and hybrid electric vehicles to propel the wheels. Various control strategies have been developed for PMSM drive systems to achieve both high efficiency and safe operation. In a PMSM drive system, generally the high voltage battery and the power...
The primary objective of a grid is to maintain a balance between generation and load. If these quantities are not in balance with each other, severe damages such as voltage fluctuations, low power quality, power outages or even cascaded blackouts may occur. Hence one of the primary factors that holds...
Renewable energy, particularly wind power, has increased dramatically over the past two decades. In the Pacific Northwest, the power system has accommodated a large amount of new wind power. The variability of wind power has introduced many challenges, requiring additional reserve generation to be available to maintain system stability. The...
Ocean wave energy converter technology continues to advance and new developers continue to emerge, leading to the need for a general design, modeling, and testing methodology. This work presents a development of the process of taking a wave energy converter from a concept to the prototype stage. A two body...
With the ever-increasing demand and competition for global energy resources among nations, it is essential to explore and tap into various energy sources to reduce dependency on global markets. Renewable energy sources offer a significant opportunity to create localized and stable energy supplies. Ocean wave energy can be a promising...
This research introduces an energy storage system to deliver microgrid frequency response. A doubly-fed induction generator (DFIG) and a squirrel cage induction machine (SCIM) are coupled together as a motor/generator set to deliver an immediate inertial response to a change of frequency, and an inverter and supercapacitors deliver short term...
Over the last 20 years, there has been rapid growth in the amount of installed wind power in the Pacific Northwest, specifically in the Columbia River Gorge. The variable and non-dispatchable nature of this resource requires that it be balanced in some form by other sources on the grid. In...
As the growth of renewable energy sources, such as wind, solar, and ocean wave, increases, their impact on the electrical grid has been rapidly escalating. Although renewable resources have been able to offset some traditional generation, they have also brought a need for increasing reserve capacity due to their non-dispatchable,...
Variable electrical generation (VG) sources such as wind farms are an increasing percentage of total electrical generation in the Bonneville Power Administration (BPA) balancing area and are starting to impact the ability of the regional balancing authority to control the electric grid. Wind farms are not dispatchable and challenge historical...
Over the last decade, wind penetration in the Pacific Northwest has increased rapidly. The variable nature of this massive new resource has increased stress on the hydropower resource to the point where system limits are currently being reached. In order to cultivate continued growth of the wind energy industry both...
Over the last decade the increase in penetration of wind power and its variable nature has begun to add considerable stress to and threatened the stability of the nation's grid. In order to continue growth wind farms will need to have the ability to participate in the same grid frequency...
The performance of the power take-off (PTO) system for a wave energy converter (WEC) depends largely on its control algorithm. This paper presents an adaptive damping control algorithm that improves power capture across a range of sea states. Validation for the numerical model was performed using data from two sources;...
The number of wind turbines and wind farms in the Pacific Northwest has increased dramatically in the past six years, which represents a significant amount of electrical generation capacity connected to the public electric grid. However, the variable nature of wind sometimes introduces excessive power, or conversely shortages, in power...
Renewable energy is a topic of significant interest and importance in the world today. Ocean wave energy, particularly in areas such as the Oregon Coast, has considerable potential as a renewable resource. However, to rightly evaluate the overall cost of energy for wave energy converters, survivability and maintenance issues must...
This work presents a residential load simulation framework that allows the user to test the effectiveness of peak reduction, peak shifting, and valley filling load management strategies on a representative residential load prior to physical smart sensor and load control deployment. The simulation methodology uses household occupancy, appliance time-of-use, and...
Ocean wave energy shows great potential as a developing form of renewable energy. However, challenges arise in maturing this technology to achieve cost-effective energy conversion. Development and testing of wave energy converters can be problematic due to the harsh environment in which they are operated. To promote development of this...
With the recent interest in increasing the penetration of renewable energy sources onto the power grid, there has been an unprecedented rapid deployment of wind generation, especially in the US Pacific Northwest. While wind farm developers have continued to expand their operations, power system operators are left to deal with...
Continual growth of the world's energy consumption and the demand for long-term clean renewable energy resources has led to the development of ocean-based wave energy technologies. Emerging technologies are advancing potential solutions to the complex problem of energy generation in the harsh and corrosive ocean environment. To develop these technologies,...
As more wind farms are connected to the grid, the variable nature of wind energy begins to influence grid stability. Energy storage could help smooth the variable nature of wind energy. Laboratory demonstration and exploration of the interaction between different energy storage devices and wind energy could help improve and...
Researchers at Oregon State University, focusing on the development of ocean wave energy converters, have designed and installed a unique linear test bed to aid in the characterization of these converters. Under the original control scheme, the linear test bed follows a position profile and is limited in its ability...
Modern wind energy is the technology of choice with a short payback period for increasing renewable energy portfolios. Bonneville Power Administration (BPA), a United States power authority in the Pacific Northwest expects to increase their wind energy capacity from 2,000 megawatts to 6,000 megawatts within the next five years. Currently...
In the year 2007, the worldwide energy consumption accumulated to a total of 16.5 billion MWh. While the resources of conventional energy production cause environmental damage, renewable energy sources like solar or wind power offer a solution to substitute for coal or nuclear generated power. Countries like Denmark and Spain...
With the increasing effort to identify alternative methods of energy generation, extraction of ocean energy has gathered a large interest. Research and industry have begun considering wave energy as the next new alternative energy. The unique challenges of ocean energy requires a wave energy converter to be both robust and...
A DC distribution system targeted for residential settings has been designed and
simulated. The system features the ability to draw power from both the utility and
photovoltaic arrays. In times of surplus solar energy, the system is able to supply power
back to the utility to facilitate net metering. The...
Ocean wave energy is rapidly becoming a field of great interest in the world of renewable energy. Significant advancements in design and technology are being made to make wave energy a viable alternative for our growing energy demands. The two major hurdles for ocean wave energy to make a significant...
Wave energy conversion devices are a rapidly growing interest worldwide for the potential to harness a sustainable and renewable energy source. Due to the oscillatory nature of ocean waves, the power generated from a permanent magnet linear generator (PMLG) for ocean wave energy conversion is pulsed. Focusing on direct drive...
Determining the performance characteristics of various ocean wave energy converters (OWEC) has proven to be difficult due to problems replicating a baseline motion profile in the ocean or wave tank to compare these devices. The linear test bed seeks to mechanically simulate the relative linear motion between the active components...