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Energy efficiency for the buildings is vital for the environment and sustainability. Buildings are responsible for significant energy consumption and carbon dioxide emissions in the United States. Using a LEED-gold-certified green office building we built a unique experimental testbed for a multi-disciplinary research project on energy efficiency. We collected the building energy data for almost a...
In this study, we propose two types of approaches to model the uncertainty in customer load demand. The first approach is based on a first order non-stationary Markov chain. A maximum likelihood estimator (MLE) is derived to estimate the time variant transition matrix of the Markov chain. The second approach is based on time series analysis techniques. We present linear prediction models such as standard...
Distributed Generation (DG), Energy Storage (ES), and Demand Response (DR) are among the essential technologies proposed in the future electricity systems (Smart Grid) initiatives. To achieve increased levels of grid penetration by DG, ES, and DR, the current distribution systems in the United States will need to undergo significant changes in both infrastructure and regulatory policy. This paper...
Today micro wind turbines are the most widely used type of wind turbine. The use of rotor tip-fan for enhancing both power conversion as well as low wind speed operation of wind turbines is investigated. It is proposed that tip-fans operating in the tangential directions create a tangential force that enhances the rotor thrust. Experiments were carried out in New Mexico State University wind tunnel...
Technologies such as Plug-in Hybrid Electric Vehicles (PHEV), Photovoltaics (PV), high efficiency electric motor drives, etc. will reduce energy related emissions and US dependency on fossil fuels and foreign oil. However commercial adoption of these technologies is slow to start due to high price and long financial payback. Silicon (Si) based power electronic systems in the above mentioned technologies...
Switched Reluctance Motor (SRM) has significant ripple in the total output torque production. The torque ripple is reflected in the speed through mechanical dynamics of the drive system. In this paper the ripple in the speed signal is used in closed loop control, to minimize the torque ripple during commutation. The speed signal can be obtained through speed sensor or estimator, which is less complicated...
Battery Energy Storage Systems play a vital role in assisting high penetration photovoltaic (PV) connections to the power grid. The development of PV, has led to concern about related reliability issues and due to inherent characteristics of PV intermittency. It has also led to investigation of using storage systems to better control renewable resources. A Smart Grid demonstration project is currently...
This paper presents modeling of interruptible loads (ILs) in an unbalanced distribution system. These ILs are then incorporated in the local distribution company's (LDC's) operational framework so as to optimally select the location (node and phase) and amount of IL for a given incentive rate offered by the LDC. The ILs are selected from the contracted customers from the LDC's perspective of minimizing...
Network development planning is a central task during the next decades due to the extension of renewable energy generation all over the world. In most countries, the geographic locations of renewable energy systems are not planned by any authority - the process is decentralized. The following analysis shows the effects of regional distribution of smaller power generation units on network development...
Forced Commutated Controlled Series Capacitor (FCSC) converters have been proposed for stand-alone wave energy conversion buoys to increase the system's power transfer capacity by preventing power factor degradation. In this paper, the effects of load changes on the operating characteristics of an FCSC circuit employed in a stand-alone wave energy conversion system are investigated, including a discussion...
In the future, a large increase in load, principally in the developing countries, is expected. This growth will force the expansion of the generation and transmission infrastructure. At the same time, many countries have set ambitious targets to increase the renewable energy generation. Furthermore, since unbundling, generation expansion planning and transmission expansion planning are carried out...
The objective of this paper is to demonstrate the sharing of demanded power in a single-phase hybrid micro grid operating in autonomous island mode. We assume that we have DC power sources such as a photovoltaic array and wind turbine in the DC sub-grid that are tied to the AC sub-grid consisting of two uninterruptible power sources (UPS) through a bi-directional single phase inverter. Demand-droop...
The capacity of installed photovoltaic (PV) generation in Japan is the world's 3rd largest and has been increasing rapidly due to the governmental subsidy and feed-in tariff programs. The rapid increase in PV installations drives electric utilities to various problems on how to operate the electric power systems stably. Then the utilities have to invest heavily in the systems. Under the circumstances,...
Materials properties of nitride semiconductors make them superior candidates for power electronics applications. Materials quality, strongly non-uniform field distribution, variations of parameters from device to device, and reliability problems have to be improved or resolved. New designs, especially suitable to nitride devices, include the use of Low Conducting Layers, “composite channel structures,...
We report on measurement and modeling of dynamic energy harvesters based on oscillating piezoelectric cantilevers, along with careful calibration of energy conversion properties of such devices in their dynamic responses. We employ thin-film lead zirconate titanate (PZT)-based cantilevers fabricated by laser micromachining, with efficient proof masses enabled by a heavy alloy with a low melting temperature...
Magna Electronics, an automotive Tier 1 Supplier, has been actively involved in the application and production of EV and Hybrid electric drive motors, inverters, electronic, and powertrain controllers. The Ford Focus Electric vehicle program includes all of these products and stand-alone inverters for the Fisker Karma, plus assorted components for other global customers. Incorporating advanced technologies...
With power conversion losses endemic in all areas of electricity consumption, broadly categorized into motion control (accounting for around 50% of total electrical energy use), lighting, air conditioning, and information technology, consumers, governments and utilities are finding ways to achieve higher efficiency. Manufacturers of data servers, telecom systems, solar power inverters and drives for...
The benefits of taking solar radiation data measurements over extended periods of months or years include 1. predicting the expected daily harvest at potential solar farm sites, and 2. determining if existing PV installations are working properly for the given solar conditions. If radiation measurements are separated into two components, i.e., sky without the beam of the sun, and the beam of the sun,...
A smart grid can be considered as an unstructured network of distributed interacting nodes represented by renewable energy sources, storage and loads. The nodes emerge or disappear in a stochastic manner due to the intermittent nature of natural sources such as wind speed and solar irradiation. Prediction and stochastic modelling of electrical energy flow is a critical characteristic in such a network...
Planning for recovery from exogenous or endogenous failures or outages of complex networks, including communications networks, power stations and entire grids as well as physical-transport networks such as pipelines, trucking, airways and railroads—for the purpose of smartly executing recovery—present planning difficulties because of the combinations of events which can occur, whether random, weather-induced,...
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