(Invited) Pulse Current Currents Transient Curve Study: Hydrogen Discharge and Modeling Attempts

Copper oxide particles were electrodeposited onto indium tin oxide (ITO) coated glass substrates. Electrodeposition was carried out in the electrolyte containing cupric sulphate, boric acid and glucopone. Both continuous and pulse currents methods were used in the process with platinum electrode, saturated calomel electrode (SCE) and ITO electrode as the counter, reference and working electrode respectively. The deposited particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that, using continuous current deposition, the deposited particles were mixture of Cu2O and CuO particles. By adding glucopone in the electrolyte, particles with spherical shapes were produced. Electrodeposition by using pulse current, uniform cubical shaped Cu2O particles were produced

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Multiple Quantum Barrier Nano-avalanche Photodiodes - Part III: Time and Frequency Responses

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666180813122642 ◽

2019 ◽

Vol 9 (2) ◽

pp. 192-197

Author(s):

Somrita Ghosh ◽

Aritra Acharyya

Keyword(s):

Optical Pulse ◽

Pulse Current ◽

Avalanche Photodiodes ◽

Simulation Method ◽

Rectangular Pulse ◽

Operating Conditions ◽

Multiple Quantum ◽

Material System ◽

Frequency Responses ◽

The Fourier Transform

Background: The time and frequency responses of Multiple Quantum Barrier (MQB) nano-scale Avalanche Photodiodes (APDs) based on Si~3C-SiC material system have been investigated in this final part. Methods: A very narrow rectangular pulse of pulse-width of 0.4 ps has been used as the input optical pulse having 850 nm wavelength incidents on the p+-side of the MQB APD structures and corresponding current responses have been calculated by using a simulation method developed by the authors. Results: Finally the frequency responses of the devices are obtained via the Fourier transform of the corresponding pulse current responses in time domain. Conclusion: Simulation results show that MQB nano-APDs possess significantly faster time response and wider frequency response as compared to the flat Si nano-APDs under similar operating conditions.

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Analytical Studies on Shrinkage Stress Distribution In GMA And Pulse Current GMA Welds Of Thick Wall Stainless Steel Pipe Having Narrow And V-Groove Design

Indian Welding Journal ◽

10.22486/iwj.v43i1.178017 ◽

2010 ◽

Vol 43 (1) ◽

pp. 14 ◽

Cited By ~ 2

Author(s):

P. K. Ghosh ◽

Ravi Ranjan Kumar ◽

K. Devakumaran

Keyword(s):

Stainless Steel ◽

Stress Distribution ◽

Pulse Current ◽

Steel Pipe ◽

Thick Wall ◽

Shrinkage Stress ◽

Groove Design ◽

Analytical Studies ◽

Stainless Steel Pipe ◽

Wall Stainless Steel

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Influence of Pulse Current Forward-Reverse Duty Cycle on Structure and Performance of Electroplated W–Cu Composite Coatings

Materials ◽

10.3390/ma14051233 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1233

Author(s):

Yuchao Zhao ◽

Nan Ye ◽

Haiou Zhuo ◽

Chaolong Wei ◽

Weiwei Zhou ◽

...

Keyword(s):

Composite Coating ◽

Duty Cycle ◽

Electrode Materials ◽

Pulse Current ◽

Electrical Discharge Machining ◽

Composite Coatings ◽

Electrical Contact ◽

Pulse Plating ◽

Fusion Welding ◽

Raw Material

Tungsten-copper (W–Cu) composites are widely used as electrical contact materials, resistance welding, electrical discharge machining (EDM), and plasma electrode materials due to their excellent arc erosion resistance, fusion welding resistance, high strength, and superior hardness. However, the traditional preparation methods pay little attention to the compactness and microstructural uniformity of W–Cu composites. Herein, W–Cu composite coatings are prepared by pulse electroplating using nano-W powder as raw material and the influence of forward-reverse duty cycle of pulse current on the structure and mechanical properties is systematically investigated. Moreover, the densification mechanism of the W–Cu composite coating is analyzed from the viewpoints of forward-pulse plating and reverse-pulse plating. At the current density (J) of 2 A/dm2, frequency (f) of 1500 Hz, forward duty cycle (df) of 40% and reverse duty cycle (dr) of 10%, the W–Cu composite coating rendered a uniform microstructure and compact structure, resulting in a hardness of 127 HV and electrical conductivity of 53.7 MS/m.

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CORROSION AND WEAR PROPERTIES OF ELECTRODEPOSITED TERTIARY NANOCOMPOSITE Zn–Ni (ALUMINA–YITTRIA–GERAPHENE) COATING

Surface Review and Letters ◽

10.1142/s0218625x17500664 ◽

2016 ◽

Vol 24 (05) ◽

pp. 1750066 ◽

Cited By ~ 1

Author(s):

HAMED RAHMANI ◽

MAHMOOD ALIOFKHAZRAEI ◽

ABDOSSALAM KARIMZADEH

Keyword(s):

Duty Cycle ◽

Zinc Sulphate ◽

Pulse Current ◽

Corrosion And Wear ◽

Pulsed Current ◽

Passive Current Density ◽

Wear Properties ◽

Nickel Zinc ◽

Pulsed Electrodeposition ◽

Passive Current

Nanocomposite Ni–Zn coatings containing 80 wt.% Al2O3, 5 wt.% Y2O3 and 15 wt.% graphene were fabricated by pulsed electrodeposition method in nickel–zinc sulphate-based electrolyte and effects of pulse current parameters on nickel and other element contents, microstructure, resistance to corrosion and tribological properties of the coatings were investigated. The pulsed current with duty cycle from 10% to 50% was applied to different samples and frequency changed gradually from 500 to 4000[Formula: see text]Hz in five steps during coating process. Increasing the duty cycle led to decrease of absorbed nanoparticles in the surface of the coatings from 4.4 vol% to 3.58 vol% The sample coated with 10% duty cycle had utmost alumina content in the coating surface, 3.5 vol% in first layer up to 4.4 vol% in fifth layer. The sample coated with 30% duty cycle had higher corrosion resistance with passive current density of 2.5[Formula: see text]mA/cm2. Furthermore, the results showed that by increasing the duty cycle, wear rate had been increased up to 1.3[Formula: see text][Formula: see text][Formula: see text]10[Formula: see text][Formula: see text]mm2/N[Formula: see text]m.

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Device for online monitoring of insulation faults in high-voltage switchgears

International Journal of Distributed Sensor Networks ◽

10.1177/1550147721999284 ◽

2021 ◽

Vol 17 (2) ◽

pp. 155014772199928

Author(s):

Jiajia Song ◽

Jinbo Zhang ◽

Xinnan Fan

Keyword(s):

Fourier Transform ◽

High Voltage ◽

Online Monitoring ◽

Pulse Current ◽

Partial Discharge ◽

Current Method ◽

Capacitive Sensor ◽

Accurate Diagnosis ◽

Partial Discharges ◽

Urgent Problem

Partial discharges are the major cause of deterioration in the insulation characteristics of switchgears. Therefore, timely detection of partial discharge in switchgear and potential insulation faults is an urgent problem that needs to be addressed in the power supervision industry. In this study, a device was proposed for online monitoring of high-voltage switchgears based on pulse current method and ozone (O3) detection. The pulse current method obtains the PD signal by monitoring the phase holes on the switch indicator. Occurrence of a partial discharge in a certain phase leads to the production of a discharge pulse, which can be coupled out by a capacitive sensor. The current spectrum and the O3 produced by partial discharge were processed via fast Fourier transform for accurate diagnosis of the occurrence of partial discharge and its severity in switchgears. The proposed method allows for convenient acquisition of the partial discharge signal, simple installation of the device, and realization with inexpensive sensors.

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