Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995909
S. Ryder
This paper presents and evaluates a number of methods for comparing the results of frequency response analysis (FRA) measurements on power and distribution transformers. It begins with a short description of FRA and its uses. This includes a short review of the literature. Existing methods for comparing the results of FRA measurements are presented and discussed. A case is made for the increased use of statistical indicators. Two different statistical indicators are presented: the correlation coefficient and the spectrum deviation. The mathematical definition of each is given. The two indicators are applied to case studies, based on actual applications of FRA to power and distribution transformers. The performance of the indicators in these case studies is evaluated, considering the importance of avoiding both false positive and false negative results. It is concluded that the correlation coefficient is a useful statistical indicator in most circumstances. It is further concluded that the spectrum deviation is an unsuitable indicator, as it is particularly prone to give false negative results in some circumstances. Recommendations are made concerning the evaluation of other statistical indicators which may be proposed in the future.
{"title":"Methods for comparing frequency response analysis measurements","authors":"S. Ryder","doi":"10.1109/ELINSL.2002.995909","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995909","url":null,"abstract":"This paper presents and evaluates a number of methods for comparing the results of frequency response analysis (FRA) measurements on power and distribution transformers. It begins with a short description of FRA and its uses. This includes a short review of the literature. Existing methods for comparing the results of FRA measurements are presented and discussed. A case is made for the increased use of statistical indicators. Two different statistical indicators are presented: the correlation coefficient and the spectrum deviation. The mathematical definition of each is given. The two indicators are applied to case studies, based on actual applications of FRA to power and distribution transformers. The performance of the indicators in these case studies is evaluated, considering the importance of avoiding both false positive and false negative results. It is concluded that the correlation coefficient is a useful statistical indicator in most circumstances. It is further concluded that the spectrum deviation is an unsuitable indicator, as it is particularly prone to give false negative results in some circumstances. Recommendations are made concerning the evaluation of other statistical indicators which may be proposed in the future.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"13 1","pages":"187-190"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80282879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995946
B. Pahlavanpour, M. Martins, A. de Pablo
The state of insulating oil in a transformer can be directly evaluated because it is easily accessible for sampling. The same is not true for insulating paper for which the condition must be evaluated using an indirect method. International experience indicates ageing of insulating paper leads to furanic compound formation;. mainly furfuraldehyde, also named furfural, or 2FAL. These compounds are soluble in the insulating oil and may be measured using a standard IEC method. However, interpretation of the results and their relation to transformer ageing is not clear. A dynamic heating experiment was conducted to examine the influence of temperature on the ageing and degradation of insulating paper in transformer oil. The furfural and gases generated were measured and their relation to paper ageing investigated. The results allow concentration of furfural in oil and furfural absorbed by paper, to be related to degree of polymerisation of the paper and to paper ageing.
{"title":"Experimental investigation into the thermal-ageing of Kraft paper and mineral insulating oil","authors":"B. Pahlavanpour, M. Martins, A. de Pablo","doi":"10.1109/ELINSL.2002.995946","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995946","url":null,"abstract":"The state of insulating oil in a transformer can be directly evaluated because it is easily accessible for sampling. The same is not true for insulating paper for which the condition must be evaluated using an indirect method. International experience indicates ageing of insulating paper leads to furanic compound formation;. mainly furfuraldehyde, also named furfural, or 2FAL. These compounds are soluble in the insulating oil and may be measured using a standard IEC method. However, interpretation of the results and their relation to transformer ageing is not clear. A dynamic heating experiment was conducted to examine the influence of temperature on the ageing and degradation of insulating paper in transformer oil. The furfural and gases generated were measured and their relation to paper ageing investigated. The results allow concentration of furfural in oil and furfural absorbed by paper, to be related to degree of polymerisation of the paper and to paper ageing.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"1 1","pages":"341-345"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72860956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995994
P. van der Wielen, P. Wouters, E. Steennis
Measuring partial discharges online in three-phase power cable systems has a number of implications on the signal interpretation as compared to offline measurements with only one phase energized. The induced currents and charges in the phase conductors and earth screen upon a PD not only depend on the discharge site, but also become phase angle dependent. Furthermore, simulations show that the PD distribution itself varies with the amount of eccentricity of the rotating field and may differ from the offline distributions obtained with a linear field. Finally, the PD propagation in a multi-conductor cable also alters the signals measured at the cable terminals. In this paper, these implications are studied by means of computer simulation.
{"title":"Signal interpretation of partial discharges in three-phase medium voltage cable systems measured on-line","authors":"P. van der Wielen, P. Wouters, E. Steennis","doi":"10.1109/ELINSL.2002.995994","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995994","url":null,"abstract":"Measuring partial discharges online in three-phase power cable systems has a number of implications on the signal interpretation as compared to offline measurements with only one phase energized. The induced currents and charges in the phase conductors and earth screen upon a PD not only depend on the discharge site, but also become phase angle dependent. Furthermore, simulations show that the PD distribution itself varies with the amount of eccentricity of the rotating field and may differ from the offline distributions obtained with a linear field. Finally, the PD propagation in a multi-conductor cable also alters the signals measured at the cable terminals. In this paper, these implications are studied by means of computer simulation.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"46 1","pages":"542-545"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73425688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995969
Y. L. Sam, P. Lewin, A. Davies, J. S. Wilkinson, S. Sutton, S. Swingler
The measurement of surface charge is important in determining the electrical performance of high voltage insulation materials. This paper is concerned with surface charge measurements utilising Pockels effect. The method proposed allows on-line measurement of charge and can generate two-dimensional images that represent the charge behaviour on a material surface. The system has been used to investigate the influence of local environment on surface charge distribution.
{"title":"The influence of local environmental conditions on surface discharge behaviour","authors":"Y. L. Sam, P. Lewin, A. Davies, J. S. Wilkinson, S. Sutton, S. Swingler","doi":"10.1109/ELINSL.2002.995969","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995969","url":null,"abstract":"The measurement of surface charge is important in determining the electrical performance of high voltage insulation materials. This paper is concerned with surface charge measurements utilising Pockels effect. The method proposed allows on-line measurement of charge and can generate two-dimensional images that represent the charge behaviour on a material surface. The system has been used to investigate the influence of local environment on surface charge distribution.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"30 1","pages":"439-443"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76395645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995962
M. Judd, P. Coventry, J. Blackett
A novel test cell is described, which is capable of providing a consistent level of partial discharge (PD) for generating UHF signals in GIS. The cell can be used to determine the sensitivity of UHF PD detection equipment. SF/sub 6/ gas is not required and the device can operate from a low-current DC supply at less than 1 kV. Its use is demonstrated in the testing of a new method for coupling UHF signals using a sensor designed to fit the test injection loop terminals of current transformers. The experiments demonstrate that contact discharges in the cell generate suitably broadband signals and show that the coupler is capable of achieving a PD detection sensitivity of <5 pC.
{"title":"Contact discharge test cell: a means of generating signals for sensitivity verification of UHF PD detection in GIS","authors":"M. Judd, P. Coventry, J. Blackett","doi":"10.1109/ELINSL.2002.995962","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995962","url":null,"abstract":"A novel test cell is described, which is capable of providing a consistent level of partial discharge (PD) for generating UHF signals in GIS. The cell can be used to determine the sensitivity of UHF PD detection equipment. SF/sub 6/ gas is not required and the device can operate from a low-current DC supply at less than 1 kV. Its use is demonstrated in the testing of a new method for coupling UHF signals using a sensor designed to fit the test injection loop terminals of current transformers. The experiments demonstrate that contact discharges in the cell generate suitably broadband signals and show that the coupler is capable of achieving a PD detection sensitivity of <5 pC.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"27 1","pages":"407-410"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82074340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995967
M. Finkel, W. Boeck, E. Kynast
The breakdown distribution functions are presented for arrangements with quasi-homogeneous field distribution and the maximum reduction of the electrical strength due to the area effect is determined. Furthermore, the influence of critical defects is discussed with respect to the on-site tests and the operation reliability. It is shown that the operation reliability of GIL can be verified with the test procedures approved for GIS.
{"title":"Verification of the operation reliability by suitable test procedures for GIL","authors":"M. Finkel, W. Boeck, E. Kynast","doi":"10.1109/ELINSL.2002.995967","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995967","url":null,"abstract":"The breakdown distribution functions are presented for arrangements with quasi-homogeneous field distribution and the maximum reduction of the electrical strength due to the area effect is determined. Furthermore, the influence of critical defects is discussed with respect to the on-site tests and the operation reliability. It is shown that the operation reliability of GIL can be verified with the test procedures approved for GIS.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"64 1","pages":"430-434"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85275753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995906
Hongyan Cao, S. Birlasekaran
Relaxation studies in oil-filled power transformers are very important to evaluate the ageing characteristics of the oil-paper insulation. The polarization processes at the interfaces can be understood by making measurements at different operating temperatures. A laboratory study is carried out using both frequency and time domain techniques. In the frequency domain technique, a dielectrometer is used and the linear response characteristics with energizing voltage magnitude up to 200 V peak are studied. In the time domain method, the recovery voltage method (RVM) up to 300 V DC is used to study the linearity in response. The obtained response is fitted to an extended Debye model and the interrelation of the model with each measuring technique is established. Then, the temperature dependence of these parameters is studied by keeping the oil-paper insulated transformer in a humidity/temperature controller for 10 hours at a certain setting. The ambient temperature is changed from 20/spl deg/C to 50/spl deg/C. The responses at high temperatures differ from the measurement at room temperature. The conductance property of the transformer insulation between two windings changes significantly. Three types of analysis are done to correlate the measurements. The first analysis is to fit the frequency and time domain responses to the extended Debye model. The determined parameters are compared to evaluate the validity. of model. In the second method of analysis with RVM, RV spectra are evaluated in term of peak magnitude variation and time shift of peak occurrence with temperature. In the third method of analysis with low frequency response, it is found that the variation of admittance and loss angle has a unique bandwidth variation with temperature. It is found that the relaxation processes of oil and oil-paper are distinctive and their dependence on temperature is different.
{"title":"Temperature dependent relaxation studies on oil-filled transformer","authors":"Hongyan Cao, S. Birlasekaran","doi":"10.1109/ELINSL.2002.995906","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995906","url":null,"abstract":"Relaxation studies in oil-filled power transformers are very important to evaluate the ageing characteristics of the oil-paper insulation. The polarization processes at the interfaces can be understood by making measurements at different operating temperatures. A laboratory study is carried out using both frequency and time domain techniques. In the frequency domain technique, a dielectrometer is used and the linear response characteristics with energizing voltage magnitude up to 200 V peak are studied. In the time domain method, the recovery voltage method (RVM) up to 300 V DC is used to study the linearity in response. The obtained response is fitted to an extended Debye model and the interrelation of the model with each measuring technique is established. Then, the temperature dependence of these parameters is studied by keeping the oil-paper insulated transformer in a humidity/temperature controller for 10 hours at a certain setting. The ambient temperature is changed from 20/spl deg/C to 50/spl deg/C. The responses at high temperatures differ from the measurement at room temperature. The conductance property of the transformer insulation between two windings changes significantly. Three types of analysis are done to correlate the measurements. The first analysis is to fit the frequency and time domain responses to the extended Debye model. The determined parameters are compared to evaluate the validity. of model. In the second method of analysis with RVM, RV spectra are evaluated in term of peak magnitude variation and time shift of peak occurrence with temperature. In the third method of analysis with low frequency response, it is found that the variation of admittance and loss angle has a unique bandwidth variation with temperature. It is found that the relaxation processes of oil and oil-paper are distinctive and their dependence on temperature is different.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"91 1","pages":"174-178"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80412651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995942
J. Reboul, M. Rouff, R. Carin
For the last ten years, space charge measurements are used to value the electrical quality of insulating materials. However, the various measurement methods are not adapted to the polymer films employed for the manufacture of power capacitors. The present work is concerned with the development of the new alternative thermal wave method based on the processing of the current response of film samples submitted to alternative thermal stimulations. A thermo-electrical module is used to generate the alternative thermal stimulations. The current response is processed as arising from an equivalent pattern of discrete charged planes parallel to the film faces. Some results obtained with this method on 100 /spl mu/m thick and 20 /spl mu/m thick polypropylene films are given. The resolving power of the method and its ability for thinner films are discussed.
{"title":"Characterization of dielectric films for power capacitors by space charge technique","authors":"J. Reboul, M. Rouff, R. Carin","doi":"10.1109/ELINSL.2002.995942","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995942","url":null,"abstract":"For the last ten years, space charge measurements are used to value the electrical quality of insulating materials. However, the various measurement methods are not adapted to the polymer films employed for the manufacture of power capacitors. The present work is concerned with the development of the new alternative thermal wave method based on the processing of the current response of film samples submitted to alternative thermal stimulations. A thermo-electrical module is used to generate the alternative thermal stimulations. The current response is processed as arising from an equivalent pattern of discrete charged planes parallel to the film faces. Some results obtained with this method on 100 /spl mu/m thick and 20 /spl mu/m thick polypropylene films are given. The resolving power of the method and its ability for thinner films are discussed.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"48 1","pages":"323-326"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90989480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995913
N. Gao, Zhan-hong Yan
Insulation diagnosis of a power transformer is a comprehensive research project that relates theories and knowledge in many different areas. With the development of computer science, the application of expert system, fuzzy logic and artificial neural network on faults diagnosis are possible. However, accomplishing the accurate and comprehensive conclusions is a problem yet unsolved. In this paper, new comprehensive diagnostic scheme is proposed. It enhances the evaluation of diagnostic results as justify by case studies.
{"title":"New approach on comprehensive diagnosis of insulation faults in power transformer","authors":"N. Gao, Zhan-hong Yan","doi":"10.1109/ELINSL.2002.995913","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995913","url":null,"abstract":"Insulation diagnosis of a power transformer is a comprehensive research project that relates theories and knowledge in many different areas. With the development of computer science, the application of expert system, fuzzy logic and artificial neural network on faults diagnosis are possible. However, accomplishing the accurate and comprehensive conclusions is a problem yet unsolved. In this paper, new comprehensive diagnostic scheme is proposed. It enhances the evaluation of diagnostic results as justify by case studies.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"6 1","pages":"203-206"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85414705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995894
Junhua Luo, Haigang Zhu, Jiang Feng, Jian Yuan
Fractals have been very successfully used to provide a description and to model mathematically many of the naturally occurring complex phenomena and shapes. Partial discharge (PD) occurring in XLPE-power cables is a cryptic phenomenon, with detectable features differing in a thousand ways. In this paper, the authors have investigated and presented preliminary results on the use of fractal features for recognition of 3-D PD patterns. This work is based on the assumption that the random 3-D PD pattern surface qualifies as a fractal surface and it was found that two fractal features, fractal. dimension and self-similar characteristic, possess reasonably good pattern recognition capabilities. According to fractal surface shapes of 3-D partial discharge patterns, correlative function and fractal dimension of the fractal surface are established in this paper. Recognition of PD signal is put forwards based on fractal features of 3-D PD patterns.
{"title":"Analysis of 3-D partial discharge patterns in XLPE power cable based on fractal theory","authors":"Junhua Luo, Haigang Zhu, Jiang Feng, Jian Yuan","doi":"10.1109/ELINSL.2002.995894","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995894","url":null,"abstract":"Fractals have been very successfully used to provide a description and to model mathematically many of the naturally occurring complex phenomena and shapes. Partial discharge (PD) occurring in XLPE-power cables is a cryptic phenomenon, with detectable features differing in a thousand ways. In this paper, the authors have investigated and presented preliminary results on the use of fractal features for recognition of 3-D PD patterns. This work is based on the assumption that the random 3-D PD pattern surface qualifies as a fractal surface and it was found that two fractal features, fractal. dimension and self-similar characteristic, possess reasonably good pattern recognition capabilities. According to fractal surface shapes of 3-D partial discharge patterns, correlative function and fractal dimension of the fractal surface are established in this paper. Recognition of PD signal is put forwards based on fractal features of 3-D PD patterns.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"6 1","pages":"116-118"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78997888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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