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Network reconfiguration is a useful method to reduce power loss in the distribution system and to also restore loads in out-of-service areas when a fault occurs. This paper presents a simple heuristic method for smart distribution system reconfiguration based on the branch-exchange method and single-loop optimization that are widely used in traditional distribution systems. The effect of switching...
In this paper, a mathematical model is developed for the steady state behavior of thyristor controlled series capacitor (TCSC). The TCSC mathematical model is developed by using firing angles of the thyristors as the modeling input. Based on the model developed and the effective TCSC reactance model presented in the literature, the steady state behavior of TCSC under varying capacitance and inductance...
Field measurements show that rapid cloud movement on solar panels ramps their maximum power output from full power to about one-third of full power in approximately five seconds, and vice-versa. When combined with high-penetration PV, this ramping may introduce the old problem of voltage flicker on distribution feeders. To study the potential flicker problem, this paper presents 1. a cloud shadow...
Gallium Nitride power devices are poised to replace silicon-based MOSFETs and IGBTs in automotive power switching applications. With its projected 100× performance advantage over silicon, GaN is a game changing technology for power electronics. This paper reviews the advantages of GaN material and devices, the performance of these devices in power circuits, and the remaining challenges facing the...
Wind energy has been widely investigated as a promising environmental friendly and economic energy resource these years worldwide. However, high volatility and non-dispatchability make it difficult to control comparing to the traditional energy. Imbalance penalty is one of the major methods to regulate wind farm owners and enhance the benefits of renewables bid into the electricity market, so as to...
A methodology to model renewable energy inverter based microgrids is developed in this paper. Most of the renewable energy sources either produce DC directly (solar photovoltaics or fuel cells) or create DC before inversion to the utility (wind or hydroelectric turbines). The DC electric energy is first conditioned and then converted into the AC grid through an inverter. The proposed method models...
In this paper goal, the comparison certainty and uncertainty information to determine the optimal place and capacity distributed generation resources in distribution network. Load uncertainty and desired voltage range has been modeled using fuzzy data theory. The objective function includes loss reduction, improvement of profile index and voltage stability index with their relevant constraints, voltage...
The structure of both electricity supply and demand is evolving rapidly. Dispersed building-scale generation is becoming an increasingly familiar generation source and electronics based loads are ubiquitous. Given this landscape, the historic advantages of AC electricity delivery, while still strong in the high voltage realm of meshed grids and medium voltage distribution, is seeming less attractive...
The world is highly dependent on an energy infrastructure that produces electricity and fuels; delivering these to customers for a wide variety of end-use applications. There is a renewed push to integrate larger quantities of variable renewable generation, advanced energy storage, and smart communications and controls to allow for increased use of sustainable generation technologies. There is also...
U.S. utilities are in the process of deploying approximately one thousand phase monitoring units, with many sites using the latest approach in virtual private network, in anticipation of applications for wide-area situational awareness and, eventually, control. The objective of the combined projects is to improve upon SCADA by including phasor data and demonstrate that better operation can be achieved...
This paper presents a dynamic analysis of a micro grid including Photovoltaic units. A four-bus system including an infinite bus is considered for the simulations. The system is modeled using MATLAB Simulink software package. Different combinations of synchronous generators and PV units are simulated and their dynamic performances during different disturbances are studied in the paper. From these...
The paper presents steady-state and transient studies to assess the impact of a 200 MW Photovoltaic Power plant (PVPP) connection on the Main Interconnected Transmission System (MITS) of Oman. The PVPP consists mainly of a large number of solar arrays, DC/DC converters, DC/AC inverters, filters, and step-up transformers. Two proposed locations are considered to connect the PVPP plant to MITS: Manah...
This paper describes progress made towards the installation of a hydrogen fueling station in Northeast Ohio. In collaboration with several entities in the Northeast Ohio area, the NASA Glenn Research Center is installing a hydrogen fueling station that uses electrolysis to generate hydrogen on-site. The installation of this station is scheduled for the spring of 2012 at the Greater Cleveland Regional...
Today's technology in data center power is moving toward the perspective of the load's need for VDC (Volts Direct Current) Power and away from a focus on how to convert VAC (Alternating Current) Grid Power to something usable. BUT, converting to Data Center VDC Power Systems is not enough. This is not VAC verses VDC, not analog verses digital, not Westinghouse verses Edison. Simply put, it is the...
This paper looks at the significance of bi-directional communication in the Smart Grid and the customer driven microgrid, a basic building block of the smart grid. It presents a classification model of communication requirements from the top down and bottom up perspective. Ultimately this paper presents future areas of work for microgrid operation that can be facilitated by a protocol specifically...
Advanced electrode materials with increased specific capacity and voltage performance are critical to the development of Li-ion batteries with increased specific energy and energy density. Although performance metrics for individual electrodes are critically important, a fundamental understanding of the interactions of electrodes in a full cell is essential to achieving the desired performance, and...
MVDC infrastructure serves as a platform for interconnecting many forms of renewable electric power generation, including wind and solar. Forthcoming abundant loads such as industrial facilities, data centers, and electric vehicle charging stations can be powered using MVDC technology. MVDC networks are expected to improve efficiency by serving as an additional layer between the transmission and distribution...
Bidirectional dc-dc converters (BDCs) are used in many applications when bidirectional energy transfer between two DC buses is needed. They are used as an interface circuit between ultra-capacitor and DC bus in a Hybrid Electric Vehicle (HEV). Since the voltage levels of the ultra-capacitor and DC bus are different, the interface circuitry must be able to increase or decrease the voltage level in...
Trend of reconfiguration of power system is leading to smart grids which are absolutely best possible solution for future power systems. Future smart grids, including Distributed Generation (DG) units, encounter a broad range of challenges like metering, management, and control. In this paper, architecture for fuzzy multi-agent based control for voltage regulation in smart grid is proposed. To investigate...
This paper proposes a dynamic output feedback decentralized pitch controller for flexible wind turbines. Both collective and cyclic (individual) pitch controllers are considered. The collective pitch controller aims at improving the rotor speed regulation and maximizing the harvested electrical power, without violating the pitch actuator limits. On the other hand, the cyclic (individual) pitch controller...
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