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Trico Electric Cooperative Inc (Trico) is a nonprofit cooperative serving more than 38,000 rural customers in southern Arizona. Trico is challenged with managing a distribution system with a wide geographical dispersion. Trico required a system to centralize, control and manage access to all of its substation devices and related data. Trico sought to diversify available substation information and...
Reliability assessments of electrical power substations have been traditionally performed assuming that the failure and repair processes are stationary and making a great simplification on the protective systems modeling. Thus, in order to improve the level of detail of these assessments, this paper presents a method that combines the modeling of failures and repairs as stochastic point processes...
Pioneering efforts in showing how electricity energy storage can be a valuable asset in a Smart Grid Distribution System have been in process for the last few years. Several demonstration projects were completed to show how substation loading could be controlled and managed to delay upgrades. The next step was to show how the load deferral benefit could be combined with distribution circuit automation...
Advances in the development of electric vehicles, along with policy incentives will see a wider uptake of this technology in the transport sector in future years. However, the widespread implementation of electric vehicles could lead to adverse effects on power system networks, especially existing distribution networks. This work investigates some of the potential impacts from various levels of uncontrolled...
Distribution Systems traditionally have a tree-like structure with several branches. They supply loads that vary through the day and as a result, some branches are loaded more than others are. By reconfiguring the system, loads from the overloaded branches may be moved to under-loaded branches. Consequently, loads in the branches can be balanced so that the real power losses are reduced and the voltage...
The failure of several transmission capacitor banks prompted The United Illuminating Company to perform an engineering study to evaluate the transient recovery voltage capabilities of existing 123-kV, oil-filled capacitor bank circuit breakers at the East Shore 115-kV substation. The study determined if the transient recovery voltage capability of existing bus and capacitor bank circuit breakers is...
Notwithstanding the positive environmental impact, the increasing penetration of Distributed Generation (DG) units connected to the distribution network raises new topics concerning the expected response of these during outages. Grid disturbances especially at the transmission level can cause the unwanted disconnection of large amounts of DG, leading to undesired power imbalances causing line overloadings...
Calculating the reliability of the power grid is difficult because it is made up of thousands of components and even though the failure mode of each component may be known, they are not independent of each other. Thus the models required to conduct reliability analysis are difficult to develop and are often complex enough to make the techniques for analysis very cumbersome. Usually controllers like...
Currently, the New England power system is highly dependent on fossil fueled generating units. The region has a significant potential for developing renewable sources of energy, including substantial inland and offshore wind resources within the region as well as in neighboring areas. ISO New England (ISO-NE) has identified the potential for up to 12,000 megawatts of wind resources within New England...
This article discusses the impact that communication will have on the electric power grid in the future. Recent efforts, such as UCA 2.0 and IEC 61850, are establishing a standard way for electric power substations, intelligent electronic devices, and other apparatus to communicate over data networks. These efforts pave the way to a future where protection and control of the electric power grid will...
This paper presents a comprehensive optimization method for the diagnosis of large substation steel grounding grid integrity status, and the detection and location of any corrosion spot before digging out the grounding grid. A grounding grid is modeled as a circuit network, and fault diagnosis equations are derived by applying Tellegen's theorem, optimization theory and fault diagnosis theory for...
Improvements in transmission and distribution networks can be noticed in most countries that had their system architecture changed by the deregulation process. In this new environment one of the biggest challenges is the transmission and distribution open access. In Brazil, the National Electricity Regulatory Agency has established that the monthly amount of transmission system usage contracted by...
Cyber threats for critical infrastructures is an area of growing concern. Data integrity attacks (e.g., manipulating sensor or control signals) on the power system through the SCADA network could have severe effects as it misleads operators into making wrong decisions. However, for an integrity attack to be successful, the malicious data should be within an acceptable range. Hence, only an attacker...
We discuss the evolving role of communication and control for automatic load management in electric distribution systems. We start by reprising a description of the Athens project - one of the earliest deployed examples of automatic load management at consumers enabled by communication signals. We observe that the use of communication for such systems has gone through distinct phases in its evolution...
Smart grid technologies for the high voltage power grid usually refer to (1) the new sensors that can sample voltages and currents at very fast rates and calculate their phase relationships by coordinating with aGPS time signal, (2) the high bandwidth communications that can move this voluminous measurement data to monitoring and control stations, and (3) fast controllers like breakers and power electronic...
Reliability of distribution systems is an important issue in power engineering for both utilities and customers. Power distribution reliability is closely related to individual component reliability. In this paper, the reliability as measured by certain count indices, mainly the System Average Interruption Duration Index (SAIDI) and the System Average Interruption Frequency Index (SAIFI), is quantified...
The interest in the integration of distributed generation into distribution systems has been increased in different countries all over the world as economic and environmental factors drive new technologies to be more efficient and less polluting than their earlier counterparts. As the penetration level of DG increases, the distribution system performance has to be analyzed in details. This work investigates...
In this paper we report on the preliminary results of a collaborative investigation effort between researchers in North America and Europe aiming to baseline the electromechanical modes and mode shapes of the Nordic system from synchronized phasor measurement data. We provide an overview on the Danish power grid and its interconnections, and describe the features of an experimental phasor measurement...
This paper describes an adaptive filtering to reduce noise in the analog input circuits of microprocessor-based protection relay (digital relay) systems. Considering that digital relays tend to have multiple functions, it is important to raise signal to noise ratios (SNR) in analog input circuits to a level that will satisfy the requirements of these functions. We have realized a noise reduction method...
We propose here a cost-effective, realistic method for testing the continuity of the grounding grid and for identifying its weak points or discontinuities. The proposed method involves injecting an ac current of ~200 A frequency not 60 Hz or 60 Hz harmonic into a grounding grid. The purpose of the frequency setting is to be able to distinguish the magnetic field produced by the injected current when...
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