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Showing 1 to 20 of 32 for “"Voltage collapse"”.
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Voltage collapse modes in power networks
Voltage Collapse is instability of a heavily loaded electric power system, which leads to declining voltages and blackout, and it is typically associated with reactive power limitations of the power system. Therefore, knowledge of the critical loading point is vital to ensure a secure mode of …
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Voltage collapse prediction for interconnected power systems
A steady state analysis is applied to study the voltage collapse problem. The modal analysis method is used to investigate the stability of the power system. Q-V curves are used to confirm the obtained results by modal analysis method and to predict the stability margin or distance to voltage …
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Study of methods to predict voltage collapse
… for a secure power system operation is the voltage collapse problem. The ever increasing size and connectivity of the power grid have lead to making the problem more multifarious. Widespread blackouts, similar to the one that occurred in the northeast in August 2003, could result from …
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The application of fuzzy decision tree for voltage collapse analysis
… As a result, the power system will be at risk to voltage collapse. Voltage collapse phenomenon is known to be complex and localised in nature but with a widespread effect. The ultimate effect of voltage collapse would be total system collapse which would incur high losses to utility companies. …
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A two step predictor-corrector method for voltage collapse point estimation
Voltage Collapse is the system failure to obtain acceptable voltage levels in significant part of the power system, and it is often due to system failure to satisfy reactive power demand. Voltage Collapse can lead to blackout like the one occurred in 2003 in North America. Methods for on-line …
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Improved computations of the voltage collapse point using the P-index
Online voltage stability assessment of power system is important to ensure reliability and security. Over the years, many voltage monitoring indices have been documented in the literature. These indices are designed to quantify proximity to voltage collapse. However, they all have inaccuracies when …
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A novel optimization formulation for the direct computation of the voltage collapse point
… of a power system is essential to assess its voltage stability condition. This point is traditionally obtained through continuation power flows which are relatively accurate but requires a considerable amount of processing time. In this work, the search for the critical loading point of a …
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An investigation into the effects of load modeling of transient stability and analysis of voltage collapse
… studies and to analyze the phenomenon of voltage collapse. In addition, the different generator models are compared and the effects of voltage dips on induction motor performance are investigated. The modeling of loads dates back to the late forties when network analyzers were still in …
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Optimal voltage stability assessment based on voltage stability indices and artificial neural network
The evaluation of voltage stability assessment experiences sizeable anxiety in the safe operation of power systems, due to the complications of a strain power system. With the snowballing of power demand by the consumers and also the restricted amount of power sources, therefore, the system has to …
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Voltage stability analysis and control in power systems
Under the title of Voltage Stability Analysis and Control, three major subjects have been examined in this PhD project: the fundamental study of voltage stability, the on-line prediction method for voltage collapse, and secondary voltage control systems. The fundamental study was aimed to lay a …
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Development and application of a new voltage stability index for on-line monitoring and shedding
During the past decades, voltage instability was the reason behind several major blackouts worldwide. Continuous assessment of the system voltage stability is vital to ensure a secured operation of the system. Several voltage stability indicators have been proposed and used in an attempt to …
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Pattern Recognition of Power Systems Voltage Stability Using Real Time Simulations
The basic idea deals with detecting the voltage collapse ahead of time to provide the operators a lead time for remedial actions and for possible prevention of blackouts. To detect cases of voltage collapse, we shall create methods using pattern recognition in conjunction with real time simulation …
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Computational Framework for Assessing Voltage Security Using Energy Methods
… set of tools for assessing and quantifying the voltage security of a power system in terms of an intuitive measure. This measure, called the maximum loading percentage (MLP), expresses the proximity of a system to serving the maximum amount of load it can furnish without experiencing a voltage …
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Voltage Stability Analysis Using Simulated Synchrophasor Measurements
… reactive power reserves initiates a sequence of voltage instability points and can ultimately lead to a system voltage collapse. Significant research have been focused on time-synchronized measurements of power systems which can be used to frequently determine the state of a power system and can …
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Hierarchical Fuzzy Control of the UPFC and SVC located in AEP's Inez Area
… controllers in the system include the Automatic Voltage Regulators (AVRs) of the generators, the controllers of the SVC, and UPFC. To coordinate the control actions of these controllers and prevent voltage instability resulting from their fighting against each other, a two level hierarchical …
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Autonomous Local Control in Distributed DC Power Systems
… interruption is shown to be useful to prevent voltage collapse, when demand exceeds supply, and to be capable of automatic load restoration upon system stabilization. In a multibus system, autonomous local controls can ensure reliable system operation by reconfiguring how the load is supplied …
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Analysis, monitoring and control of voltage stability in electric power systems
… in this text concentrates on three aspects of voltage stability studies: analysis and determination of suitable proximity indicators, design of an effective real-time monitoring system, and determination of appropriate emergency control techniques. A simulation model of voltage collapse was …
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The impact of wind generation on power system voltage stability
… power system operation and planning in terms of voltage stability. Also, power flow pattern and system's dynamic characteristics change when large percentages of wind generation are connected to the grid. Wind generation is characterised by its variability and intermittency, and as such present …
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Hoeffding-Tree-Based Learning from Data Streams and Its Application in Online Voltage Security Assessment
… addressed by IEEE and CIGRE Task Force, voltage stability refers to the stability of maintaining the steady voltage magnitudes at all buses in a power system when the system is subjected to a disturbance from a given operating condition (OC). Cascading outage due to voltage collapse is a …
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