Experimental investigation on anthracite coal fragmentation by high-voltage electrical pulses in the air condition: Effect of breakdown voltage

The low gas permeability of coal formations with limited coal pores and fractures leads to difficulty in coalbed methane exploration. High-voltage electrical pulse has a potential application in enhanced coalbed methane recovery. In this study, we discuss the microscopic characteristics of anthracite coals treated by high-voltage electrical pulse. We find that C, O, and other coal elements constituting oxygenic groups, which mainly account for gas adsorption, decreased slightly after high-voltage electrical pulse treatment, indicating that elemental variation may have little influence on gas adsorption. The scanning electron microscopy and low-pressure nitrogen gas adsorption (LP-N2GA) results show that the cumulative micropore volumes of high-voltage electrical pulse-treated coals were much larger than those of original coals. The mercury intrusion porosimetry results show that the cumulative macropore volumes, which act as gas migration channels in coal increased. Additionally, high-voltage electrical pulse-treated coals were found to have smaller entrapment areas, indicating that gas migration was enhanced.

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Experimental Investigation of Insulating Properties of Vegetable Oil under High Voltage

European Journal of Engineering Research and Science ◽

10.24018/ejers.2019.4.1.1047 ◽

2019 ◽

Vol 4 (1) ◽

pp. 17-23 ◽

Cited By ~ 4

Author(s):

Sanjida Islam ◽

Md. Selim Hossain ◽

Md. Farhamdur Reza ◽

Md. Mamunur Rashid

Keyword(s):

Experimental Investigation ◽

Breakdown Voltage ◽

Palm Oil ◽

High Voltage ◽

Coconut Oil ◽

Cost Effective ◽

Transformer Oil ◽

Insulating Oil ◽

High Breakdown Voltage ◽

Mixed Oil

Due to concerns over the world’s energy necessity and environmental impact of mineral oil, these conditions induce many researchers to search for substitute sources for insulating oil. Alternatives insulating oil with biodegradable characteristics, environment friendly and presented in different countries including Bangladesh such as vegetable oils have been proposed for high voltage applications. In this paper, a relative measurement of breakdown voltage through experimental investigation of coconut, mustard, soybean, and palm oil and their blend (which is available in Bangladesh and cost effective) is presented. Break down voltage was measure with different electrode configuration by changing gap distance. The results show that the blend of (50% coconut oil + 50% palm oil) got high breakdown voltage in mushroom-mushroom electrode, and other side in plane-plane type pure soybean oil got high breakdown voltage, compared with transformer oil. The presented result illustrate that the proposed mixed oil provides better performance than the rise husk oil.

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On the Breakdown Voltage Temperature Dependence of High-Voltage Power Diode Passivated with Diamond-Like Carbon

10.1109/eurosoi-ulis53016.2021.9560184 ◽

2021 ◽

Author(s):

Luigi Balestra ◽

Susanna Reggiani ◽

Antonio Gnudi ◽

Elena Gnani ◽

Jagoda Dobrzynska ◽

...

Keyword(s):

Temperature Dependence ◽

Breakdown Voltage ◽

High Voltage ◽

Diamond Like Carbon ◽

Power Diode

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Design of a Low on Resistance High Voltage (120V) Novel 3D NLDMOS with Side Isolation Based on 0.35um BCD Process Technology

MATEC Web of Conferences ◽

10.1051/matecconf/201820102004 ◽

2018 ◽

Vol 201 ◽

pp. 02004

Author(s):

Shao-Ming Yang ◽

Gene Sheu ◽

Tzu Chieh Lee ◽

Ting Yao Chien ◽

Chieh Chih Wu ◽

...

Keyword(s):

Breakdown Voltage ◽

High Voltage ◽

High Performance ◽

Power Device ◽

Simulation Tool ◽

Process Technology ◽

Surface Field ◽

Kirk Effect ◽

Tcad Simulation ◽

Reduced Surface

High performance power device is necessary for BCD power device. In this paper, we used 3D Synopsis TCAD simulation tool Sentaurus to develop 120V device and successfully simulated. We implemented in a conventional 0.35um BCDMOS process to present of a novel high side 120V LDMOS have reduced surface field (RESURF) and Liner p-top structure with side isolation technology. The device has been research to achieve a benchmark specific on-resistance of 189 mΩ-mm2 while maintaining horizontal breakdown voltage and vertical isolation voltage both to target breakdown voltage of 120V. In ESOA, we also proposed a better performance of both device without kirk effect.

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New Experimental Investigation of Magnetic and Electric Fields in the Vicinity of High-Voltage Power Lines

Journal of Magnetics ◽

10.4283/jmag.2016.21.1.102 ◽

2016 ◽

Vol 21 (1) ◽

pp. 102-109 ◽

Cited By ~ 1

Author(s):

Said Ghnimi ◽

Adnen Rajhi ◽

Ali Gharsallah

Keyword(s):

Experimental Investigation ◽

Electric Fields ◽

High Voltage ◽

Power Lines ◽

High Voltage Power Lines

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Investigation on the Breakdown Characteristics of Different Types of Lightning Rods

ELEKTRIKA- Journal of Electrical Engineering ◽

10.11113/elektrika.v17n2.30 ◽

2018 ◽

Vol 17 (2) ◽

pp. 1-5

Author(s):

Noor Azlinda Ahmad ◽

Rosniza Zainal ◽

Zuraimy Adzis

Keyword(s):

Breakdown Voltage ◽

High Voltage ◽

Horizontal Distance ◽

Different Types ◽

Series Of Experiments ◽

Voltage Breakdown

This paper investigates the voltage breakdown characteristics of three types of lightning rods - blunt, sharp and flat. The objectives of this study are to determine the voltage breakdown characteristics of various types of lightning rods and to obtain the striking distance of each rod. A series of experiments were conducted in the high voltage laboratory consisting of individual testing rod, competitive testing rod and also horizontal distance changing. All three types of rods have been tested in each experiment in order to obtain a comprehensive result. The blunt rod has been proven as the best strike receptor in comparison to sharp and flat rod. This is because breakdown voltage for blunt rod is much lower (199 kV) than that of flat and sharp rod. Therefore, replacement of widely used sharp rod with the blunt one should be considered in order to provide better protection for buildings from lightning activities.

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The research on breakdown voltage of high voltage SOI LDMOS devices with shielding trench

2001 6th International Conference on Solid-State and Integrated Circuit Technology. Proceedings (Cat. No.01EX443) ◽

10.1109/icsict.2001.981446 ◽

2002 ◽

Cited By ~ 1

Author(s):

Qiyu Liu ◽

Zhaoji Li ◽

Bo Zhang ◽

Jian Fang

Keyword(s):

Breakdown Voltage ◽

High Voltage

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Thermal breakdown in high voltage direct current cable insulations due to space charges

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-12-2017-0531 ◽

2018 ◽

Vol 37 (5) ◽

pp. 1689-1697 ◽

Cited By ~ 2

Author(s):

Christoph Jörgens ◽

Markus Clemens

Keyword(s):

Electric Field ◽

Breakdown Voltage ◽

High Voltage ◽

Direct Current ◽

Aging Effect ◽

Radial Symmetry ◽

Thermal Breakdown ◽

Content Type ◽

High Voltage Direct Current ◽

Space Charges

Purpose In high voltage direct current (HVDC), power cables heat is generated inside the conductor and the insulation during operation. A higher amount of the generated heat in comparison to the dissipated one, results in a possible thermal breakdown. The accumulation of space charges inside the insulation results in an electric field that contributes to the geometric electric field, which comes from the applied voltage. The total electric field decreases in the vicinity of the conductor, while it increases near the sheath, causing a possible change of the breakdown voltage. Design/methodology/approach Here, the thermal breakdown is studied, also incorporating the presence of space charges. For a developed electro-thermal HVDC cable model, at different temperatures, the breakdown voltage is computed through numerical simulations. Findings The simulation results show a dependence of the breakdown voltage on the temperature at the location of the sheath. The results also show only limited influence of the space charges on the breakdown voltage. Research limitations/implications The study is restricted to one-dimensional problems, using radial symmetry of the cable, and does not include any aging or long-term effect of space charges. Such aging effect can locally increase the electric field, resulting in a reduced breakdown voltage. Originality/value A comparison of the breakdown voltage with and without space charges is novel. The chosen approach allows for the first time to assess the influence of space charges and field inversion on the thermal breakdown.

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