On-line Method for High-sensitivity Leakage Current Measurement of Converter-connected Transformers in Microgrids

Abstract Leakage current measurement plays an important role in determining the healthiness of high voltage insulation of a power apparatus. High voltage (HV) insulation degrades due to electrical, thermal and mechanical ageing and their cumulative effects, and thus the leakage current of the insulation increase over a period of time. The accurate and real time measurement of leakage current enables the utilities to on-line access the healthiness of the insulation. This paper describes about the design, development, calibration and testing of a novel non-contact type passive leakage current sensor which can be used for monitoring of various electrical devices based on the analysis of the leakage current captured by the sensor. The developed sensor has been successfully used for measurement of leakage current in oil-filled HV bushings as well as in gas insulated surge arresters. The sensitivity of the developed sensor as per its design can be in the order of few milli amperes in case of bushing and in the order few micro amperes for surge arrester monitoring. The paper also reported a novel design of bushing adapter-sensor assembly for on-line measuring the leakage current in HV bushings without using the conventional capacitive or resistive tapping based measurements. Further, results covering experimental leakage current measurement on a 420 kV bushing using the developed adapter sensor assembly have also been presented. To establish capabilities of the developed sensor with optimized design parameters, laboratory measurements of leakage current on 420 kV and 145 kV GIS surge arresters have also been carried out and reported in the paper. Third harmonic content of surge arrester leakage current has also been estimated in-line with IEC requirement to assess the healthiness of the surge arrester. Finally, suitability of the developed sensor for leakage current measurement of above power apparatus equipment has also been analyzed and discussed.

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DC Leakage Current Measurement Comparison between SF6 and Fluoronitrile/CO2 Gas Mixture

2020 IEEE 3rd International Conference on Dielectrics (ICD) ◽

10.1109/icd46958.2020.9341823 ◽

2020 ◽

Author(s):

C. Toigo ◽

T. Vu-Cong ◽

F. Jacquier ◽

A. Girodet

Keyword(s):

Leakage Current ◽

Current Measurement ◽

Gas Mixture ◽

Co2 Gas

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A rapid on-line method for mass spectrometric confirmation of a cysteine-conjugated antibody-drug-conjugate structure using multidimensional chromatography

mAbs ◽

10.1080/19420862.2015.1083665 ◽

2015 ◽

Vol 7 (6) ◽

pp. 1036-1044 ◽

Cited By ~ 47

Author(s):

Robert E Birdsall ◽

Henry Shion ◽

Frank W Kotch ◽

April Xu ◽

Thomas J Porter ◽

...

Keyword(s):

Mass Spectrometric ◽

Antibody Drug Conjugate ◽

Multidimensional Chromatography ◽

Drug Conjugate ◽

Line Method ◽

On Line ◽

Antibody Drug

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High-Resolution Laser Spectroscopy of theDLines of On-Line ProducedNa21,22,24,25Using a New High-Sensitivity Method of Detection of Optical Resonances

Physical Review Letters ◽

10.1103/physrevlett.34.1209 ◽

1975 ◽

Vol 34 (19) ◽

pp. 1209-1211 ◽

Cited By ~ 72

Author(s):

G. Huber ◽

C. Thibault ◽

R. Klapisch ◽

H. T. Duong ◽

J. L. Vialle ◽

...

Keyword(s):

High Resolution ◽

Laser Spectroscopy ◽

High Sensitivity ◽

Optical Resonances ◽

On Line ◽

Sensitivity Method

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Research on Compressed Sensing Matrix Based on Data Compressing of Insulator Leakage Current

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.475-476.451 ◽

2013 ◽

Vol 475-476 ◽

pp. 451-454

Author(s):

Xue Ming Zhai ◽

Xiao Bo You ◽

Ruo Chen Li ◽

Yu Jia Zhai ◽

De Wen Wang

Keyword(s):

Compressed Sensing ◽

Data Compression ◽

Leakage Current ◽

Sparse Matrix ◽

Circulant Matrix ◽

Measurement Matrix ◽

Sensing Matrix ◽

Significant Step ◽

On Line

Insulator fault may lead to the accident of power network,thus the on-line monitoring of insulator is very significant. Low rates wireless network is used for data transmission of leakage current. Making data compression and reconstruction of leakage current with the compressed sensing theory can achieve pretty good results. Determination of measurement matrix is the significant step for realizing the compressed sensing theory. This paper compares multiple measurement matrix of their effect via experiments, putting forward to make data compression and reconstruction of leakage current using Toeplitz matrix, circulant matrix and sparse matrix as measurement matrix, of which the reconstitution effect is almost the same as classical measurement matrix and depletes computational complexity and workload.

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Progress In Design and Applications Of CCD Cameras For Electron Microscopy

Microscopy Today ◽

10.1017/s1551929500065652 ◽

1995 ◽

Vol 3 (10) ◽

pp. 12-13 ◽

Cited By ~ 1

Author(s):

Kenneth H. Downing

Keyword(s):

High Sensitivity ◽

Ccd Cameras ◽

Video Cameras ◽

Quantum Leap ◽

Fluorescent Screen ◽

Lower Beam ◽

Video Systems ◽

On Line ◽

Specimen Quality ◽

Electron Microscopes

Over the last several years the long-awaited revolution in direct-digital readout systems has begun, with the introduction of efficient slow-scan CCD cameras. Earlier, the introduction of video cameras to electron microscopes had brought a quantum leap in the speed and efficiency of carrying out a host of operations. The high sensitivity of the video cameras provided the ability to see the image in much more detail and at a lower beam intensity than had been previously possible by viewing the fluorescent screen. The ability to assess, on line, characteristics such as specimen quality and image focus, even qualitatively, gave feedback to the operator that previously took hours to obtain. Due to the low resolution of these video systems, however, they were rarely useful for data recording.

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