Transient analysis of a 22.9 kV/2 kA HTS cable under short circuit using equivalent circuit model considering different fault parameters

With the development of technology, the power system of offshore facilities (for short: power system) is increasingly complex, short-circuit current calculation process also becomes more complex. The simple recursive algorithm can not meet the requirements of short-circuit current calculation in complex power system. The paper, basing on the principle of short-circuit current calculation, taking modeling ideas, created an equivalent circuit model of power system for short-circuit current calculation. The equivalent circuit model can be used to simplify the progress of calculation and meet the needs of the power system development.

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Discharge by Short Circuit Currents of Parallel-Connected Lithium-Ion Cells in Thermal Propagation

Batteries ◽

10.3390/batteries5010018 ◽

2019 ◽

Vol 5 (1) ◽

pp. 18 ◽

Cited By ~ 3

Author(s):

Sascha Koch ◽

Alexander Fill ◽

Katerina Kelesiadou ◽

Kai Birke

Keyword(s):

Equivalent Circuit ◽

Short Circuit ◽

Equivalent Circuit Model ◽

Lithium Ion ◽

Thermal Runaway ◽

Circuit Model ◽

Test Series ◽

Lithium Ion Cells ◽

Short Circuit Currents ◽

Thermal Propagation

The increasing need for high capacity batteries in plug-in hybrids and all-electric vehicles gives rise to the question of whether these batteries should be equipped with a few large capacity cells or rather many low capacity cells in parallel. This article demonstrates the possible benefits of smaller cells connected in parallel because of discharge effects. Measurements have been conducted proving the beneficial influence of a lower SoC on the thermal runaway behaviour of lithium-ion cells. A second test series examines the short circuit currents during an ongoing thermal propagation in parallel-connected cells. With the help of a developed equivalent circuit model and the results of the test series two major system parameters, the ohmic resistance of a cell during thermal runaway R tr and the resistance post thermal runaway R ptr are extracted for the test set-up. A further developed equivalent circuit model and its analytical description are presented and illustrate the great impact of R ptr on the overall discharged capacity. According to the model, cells with a capacity of no more than C cell = 10–15 Ah and a parallel-connection of 24 cells show the most potential to discharge a significant amount.

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Transient Analysis of Asymmetric Multi Quantum Well Laser using Equivalent Circuit Model

2007 IEEE International Conference on Signal Processing and Communications ◽

10.1109/icspc.2007.4728310 ◽

2007 ◽

Author(s):

Abbas Zarifkar ◽

Sasan Seifollahpour

Keyword(s):

Quantum Well ◽

Equivalent Circuit ◽

Transient Analysis ◽

Equivalent Circuit Model ◽

Circuit Model ◽

Quantum Well Laser ◽

Multi Quantum Well

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Highly Efficient Dye-sensitized Solar Cells

MRS Proceedings ◽

10.1557/opl.2011.1121 ◽

2011 ◽

Vol 1327 ◽

Cited By ~ 1

Author(s):

Liyuan Han ◽

Ashraful Islam

Keyword(s):

Solar Cells ◽

Equivalent Circuit ◽

Electrochemical Impedance ◽

Short Circuit ◽

Dye Sensitized Solar Cells ◽

Equivalent Circuit Model ◽

Alkyl Substituent ◽

Circuit Model ◽

Dye Sensitized ◽

Sensitized Solar Cells

ABSTRACTThe present paper discusses the principle of dye-sensitized solar cells (DSCs) in terms of equivalent circuit model and the key issues to improve the device efficiency. Equivalent circuit model is proposed following analysis by electrochemical impedance spectroscopy of the voltage dependence of the internal resistance elements of DSCs. The influence of these elements upon cell performance in areas such as short circuit current density (Jsc), open circuit voltage (Voc), and fill factor (FF) was examined based on the equivalent circuit. Efficient sensitization of nanocrystalline TiO2 film was observed across the whole visible range and into the near-IR region as far as 1000 nm with a new panchromatic substituted β-diketonato Ru(II)-terpyridine dye (HIG1). Introduction of bulky alkyl substituent group in a β-diketonato Ru(II)-terpyridine dye (A3) suppress aggregate formation result in an improved performance of DSCs and the performance is independent of the additive added during the dye adsorption process. The haze factor of TiO2 electrodes is a useful index when fabricating light-confined TiO2 electrodes to improve Jsc. It was demonstrated that blocking of bare TiO2 surface with small molecules is an effective way of suppress interfacial charge recombination at the TiO2-dye/electrolyte interface and of improving shunt resistance and Voc. FF was also improved by reduction of the internal series resistance, which is composed of the following three elements: the redox reaction resistance at the platinum counter electrode, the resistance of carrier transport by ions in the electrolyte, and resistance due to the sheet resistance of the transparent conducting oxide. Finally, the highest efficiency scores of 10.4% and 11.1% (aperture illumination area 1.004cm2 and 0.219cm2, respectively) were confirmed by a public test center.

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