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Polarity-reversed voltage pulse propagation analysis for power cable insulation diagnosis
Proceedings of 2014 International Symposium on Electrical Insulating Materials, 2014Water tree degradation is major problem for power transmission cables. Water treeing is typical of the processes involved in the aging of XLPE cables, and it is known that it causes degradation of insulation performance. To avoid catastrophic failure, a method for localization of this water-treed section is required.
Ryotaro Ozaki +4 more
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Analysis of transient electric fields under two different polarity reversal voltages
2011 IEEE Power Engineering and Automation Conference, 2011A typical model of converter transformer is adopted to study the linear and nonlinear electric fields of PR (Polarity Reversal) under the step voltage and ramp voltage, and the results show that the short duration of changing polarity should not be neglected when analyze the nonlinear electric fields of the actual converter transformer or bushing, on ...
null Gang Liu +5 more
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Space charge behavior in oil-paper insulation under polarity reversed voltage
2012 IEEE International Conference on Condition Monitoring and Diagnosis, 2012Converter transformers are suffered from DC voltage, DC voltage with AC voltage and polarity reversed voltage additionally, compared with common power transformers. Under DC voltage it is easy to form space charge in oil-paper insulation. The formation, distribution and mobility of space charge will affect its dielectric performance.
Da Wang +4 more
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2010 Design, Automation & Test in Europe Conference & Exhibition (DATE 2010), 2010
This paper presents an innovative and effective approach to design and test a regulator for an automotive alternator with programmable functionalities. The prototype system consists of two different parts: an integrated circuit (IC) and a FPGA. The IC, implemented in austriamicrosystems HVCMOS 0.35 μm technology, includes all the high voltage parts and
FANUCCI, LUCA +7 more
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This paper presents an innovative and effective approach to design and test a regulator for an automotive alternator with programmable functionalities. The prototype system consists of two different parts: an integrated circuit (IC) and a FPGA. The IC, implemented in austriamicrosystems HVCMOS 0.35 μm technology, includes all the high voltage parts and
FANUCCI, LUCA +7 more
openaire +3 more sources
Electrical tree initiation in silicone rubber under DC and polarity reversal voltages
Journal of Electrostatics, 2017Abstract With the fast development of high voltage DC (HVDC) cable, cable insulation under DC conditions has got more attention. In this paper, tests were conducted to study the electrical tree initiation in silicone rubber (SIR) under DC and polarity reversal voltages.
Yunxiao Zhang +5 more
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Calculation of transient electric field of converter transformer under polarity reversal voltage
Digests of the 2010 14th Biennial IEEE Conference on Electromagnetic Field Computation, 2010A state space finite element method is presented for the calculation of transient electric field in oil-immersed insulation system of converter transformer. Firstly, the state equation is derived based on the quasi-static electric field theory, combined with the given boundary value using the penalty method, which has a clear physical meaning. Secondly,
null Lin Li +3 more
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Polarization reversal and capacitance-voltage characteristic of epitaxial Pb(Zr,Ti)O3 layers
Applied Physics Letters, 2005Capacitance-voltage (C–V) measurements were performed on epitaxial layers of Pb(Zr0.2Ti0.8)O3 (PZT) with top and bottom SrRuO3 (SRO) electrodes. It is shown that the sharp capacitance peak∕discontinuity which is present in the C–V characteristics at different frequencies is directly associated with the polarization reversal.
L. Pintilie, M. Lisca, M. Alexe
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A Deeper Insight in Predicting the Effect of Voltage Polarity Reversal on HVDC Cables
2019 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP), 2019The reversal of voltage polarity is essential in HVDC cable systems with Current Source Converters (CSC), since it enables to revert the direction of the power flow. In a previous paper by the authors a life model for HVDC cables subjected to voltage polarity reversal was developed and applied for predicting the life of HVDC cables subjected to a ...
A. Battaglia, M. Marzinotto, G. Mazzanti
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Allan Variances and Spectral Densities for DC Voltage Measurements With Polarity Reversals
IEEE Transactions on Instrumentation and Measurement, 2005Using a polarity reversal technique, precise dc voltage measurements were made with both digital and analog voltmeters. The results were analyzed by calculating Allan variances and spectral densities for polarity-reversed measurements and comparing them with similar analyses of unreversed or unipolar measurements of the same processes.
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Analytical Chemistry, 2017
Continuous efforts have been made to further improve the performance of nano-ESI. In this work, we made use of a polarity-reversing high-voltage strategy for the generation of nano-ESI (PR-nESI). Typically, a negative high voltage of -3.0 kV was first applied to the electrode and maintained for 6 s.
Xiaoyun Gong +4 more
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Continuous efforts have been made to further improve the performance of nano-ESI. In this work, we made use of a polarity-reversing high-voltage strategy for the generation of nano-ESI (PR-nESI). Typically, a negative high voltage of -3.0 kV was first applied to the electrode and maintained for 6 s.
Xiaoyun Gong +4 more
openaire +2 more sources