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Theory of current-voltage instabilities in superlattices
Physical Review B, 1993The theory of the uniform electric-field distribution instability in superlattices is developed. The instability with respect to high-field domain formation was discovered some time ago by Esaki and Chang but no microscopic theory has been proposed so far.
, Laikhtman, , Miller
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On voltage stability monitoring with voltage instability predictors
2013 IREP Symposium Bulk Power System Dynamics and Control - IX Optimization, Security and Control of the Emerging Power Grid, 2013After 15 years of use, voltage instability identification techniques based on determination of Thevenin-like equivalents have matured, but many issues remain. In this paper, some of them are addressed - computing, as well as some ideas about handling systems with pronounced transmission corridors (flowgates).
Cui Bai +4 more
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Thermal instability of low voltage power-MOSFETs
30th Annual IEEE Power Electronics Specialists Conference. Record. (Cat. No.99CH36321), 2000Anomalous failures which occurred inside the theoretical forward biased safe operating area of the latest generation low voltage power MOS devices are reported and analyzed. The paper outlines how some technology improvements, while increasing the current capability, can induce thermal instability phenomena at low drain currents.
A. CONSOLI +6 more
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Robust Voltage Instability Predictor
IEEE Transactions on Power Systems, 2016This letter presents a robust voltage instability predictor using local noisy PMU measurements. A robust recursive least squares estimation is proposed to mitigate the impacts of gross PMU measurement errors on estimating the bus impedance and the Thevenin equivalent impedance used for voltage stability analysis.
Junbo Zhao +3 more
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The dynamics of system voltage instability
Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95, 2002A method of simulating the post-disturbance dynamics of system voltage instability has been developed in which both the slow and fast phases, reported in incidents, have been replicated by a series of load flows. An analysis of the simulation has shown that changes of voltages and reactive power outputs can not only identify a critical situation but ...
W.R. Lachs, D. Sutanto
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An investigation of voltage instability problems
IEEE Transactions on Power Systems, 1992The authors investigate the voltage stability problem based on singular perturbation theory. Possible voltage instability patterns are classified into four types (I, II-1, II-2S, and II-2D) according to the mechanism causing voltage instability. Several features of each type of instability are studied as well as their analysis methods.
N. Yorino +5 more
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Noise voltage and instability in GaAs devices
Applied Physics Letters, 1988Low-frequency current noise that has a f−3/2 power law noise spectrum is observed in GaAs field-effect devices. We show that this is due to modulation by a thermally activated and bias-independent voltage noise in the gate. We identify this noise with generation recombination associated with the semi-insulating substrate supporting these devices ...
D. J. Day +3 more
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Large Scale Voltage Instability
2012In this chapter, we apply the methods of state-space geometry to the issue of complex power optimization in a non-steady state regime by incorporating the intrinsic state-space geometry. Considering the power flow between two arbitrary points along the chosen transmission line, we compute the stability domains for a large voltage instability problem ...
Stefano Bellucci +2 more
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Voltage instability and reactive planning
IEEE Power Engineering Society General Meeting, 2004., 2004Trading power across transmission systems has become one of the most important activities in the deregulated electric power industry worldwide. In addition to the power trading, serving native loads and power transactions based on reciprocity are still common among utilities in different regions, seeking both economic and reliability benefits.
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A method for local voltage instability assessment
MELECON '98. 9th Mediterranean Electrotechnical Conference. Proceedings (Cat. No.98CH36056), 2002Voltage instability is a nonlinear local phenomenon, which occurs due to insufficient reactive power production or as an inability to transfer it to consumers. In most dangerous cases, it can result in voltage collapse. Therefore early identification of the process is essential. A power system is decomposed into selected radial paths regarding reactive
F. Gubina, D. Grgic, B. Strmcnik
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