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Observability analysis and estimation of transformer tap settings.
2003 IEEE Bologna Power Tech Conference Proceedings,, 2004This paper presents a numerical algorithm for observability analysis in a state estimation model which treats transformer tap settings as state variables and provides for turns ratio and phase-shift angle measurements. The proposed model is (transformed to a conventional node frame of reference formulation, by introducing two fictitious buses and ...
P.J. Katsikas +2 more
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Observability and estimation of transformer tap setting with minimal PMU placement
2008 IEEE Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century, 2008One of the most important applications of phasor measurement units (PMUs) is power system state estimation. Some models have been proposed for including phasor measurements in the state estimation. But, all of these models have treated transformer tap settings (voltage transformer turns ratio and phase-shift transformer angle) as fixed parameters of ...
M. Shiroie, S. H. Hosseini
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Optimal Tap Setting of Voltage Regulation Transformers in Unbalanced Distribution Systems
IEEE Transactions on Power Systems, 2016In this paper, we propose a method to optimally set the tap position of voltage regulation transformers in distribution systems. We cast the problem as a rank-constrained semidefinite program (SDP), in which the transformer tap ratios are captured by 1) introducing a secondary-side “virtual” bus per transformer, and 2) constraining the values that ...
Brett A. Robbins +2 more
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Can Personal Goal Setting Tap the Potential of the Gifted Underachiever?
Roeper Review, 2010Although underachieving gifted students have been largely ignored in empirical research, there has been a modest surge of interest in describing and “treating” this population in recent years. It is estimated that nearly half of gifted youth achieve significantly below their potential.
Dominique Morisano, Bruce M. Shore
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State estimation of voltage and phase-shift transformer tap settings
IEEE Transactions on Power Systems, 1992A transformer tap estimation technique is presented that overcomes earlier limitations because of a direct algorithmic approach. The procedure provides for turn ratio and phase angle measurements, and treats each transformer tap setting as an independent state variable.
P.A. Teixeira +4 more
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Variable voltage set point control of tap changers in distribution grids
IEEE PES Innovative Smart Grid Technologies, Europe, 2014This paper discusses changing requirements for tap changer controllers in distribution grids with high penetration of renewable generation. Furthermore, a new tap changer controller approach based on a power flow dependent voltage set point curve using hysteresis is introduced.
E.-M. Baerthlein +2 more
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Optimization of fixed tap transformer setting in bulk electric systems
IEEE Transactions on Power Systems, 1991A novel technique was developed to determine fixed tap transformer settings that are optimal for several load patterns representing, for example, winter peak, summer peak, and off-peak loading patterns. The solution algorithm is based on the Newton approach and employs a recently developed technique to identify binding inequality constraints. A special
W. Kellerman +3 more
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Use of Tap Water and Disinfection Practices in Outpatient Settings: A Survey of Otolaryngologists
Archives of Otolaryngology - Head and Neck Surgery, 1991A survey of otolaryngologists belonging to the American Academy of Otolaryngology-Head and Neck Surgery was conducted to estimate the frequency of tap water use during otologic examinations and to assess methods used for disinfection of otologic instruments in outpatient settings. Questionnaires were returned by 516 persons residing in 49 states.
P W, Lowry, W R, Jarvis
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Journal of Applied Physics, 2010
There is great interest in using proximal probe techniques to simultaneously image and measure physical properties of surfaces with nanoscale spatial resolution. In this regard, there have been recent innovations in generating time-resolved force interaction between the tip and surface during regular operation of tapping mode atomic force microscopy ...
Bharath Kumar +3 more
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There is great interest in using proximal probe techniques to simultaneously image and measure physical properties of surfaces with nanoscale spatial resolution. In this regard, there have been recent innovations in generating time-resolved force interaction between the tip and surface during regular operation of tapping mode atomic force microscopy ...
Bharath Kumar +3 more
openaire +1 more source