Pub Date : 2010-11-18DOI: 10.1109/ICHVE.2010.5640856
H. Kojima, Hideaki Yasukawa, R. Nishimura, H. Okubo, H. Sato, H. Saito, Y. Noda
As vacuum attracts attention from a viewpoint of high insulation performance and environmental-friendliness, vacuum circuit breakers (VCBs) are expected to develop into higher voltage level. In this paper, we discuss the relations between the surface state and the conditioning mechanism of Cu-Cr electrode during impulse voltage application process in vacuum. The experimental results showed that the deposited layer at the cathode surface was formed by the anode material due to the impulse voltage application process. We finally clarified and concluded that under impulse voltage application process, characteristics of the cathode surface are changing to those of the anode material, and anode material could determine the final states of conditioning process.
{"title":"Improvement of Cu-Cr electrode surface under impulse voltage conditioning in vacuum","authors":"H. Kojima, Hideaki Yasukawa, R. Nishimura, H. Okubo, H. Sato, H. Saito, Y. Noda","doi":"10.1109/ICHVE.2010.5640856","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640856","url":null,"abstract":"As vacuum attracts attention from a viewpoint of high insulation performance and environmental-friendliness, vacuum circuit breakers (VCBs) are expected to develop into higher voltage level. In this paper, we discuss the relations between the surface state and the conditioning mechanism of Cu-Cr electrode during impulse voltage application process in vacuum. The experimental results showed that the deposited layer at the cathode surface was formed by the anode material due to the impulse voltage application process. We finally clarified and concluded that under impulse voltage application process, characteristics of the cathode surface are changing to those of the anode material, and anode material could determine the final states of conditioning process.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127983432","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640812
Jeongtae Kim, Jaecheol Jeong, Jihong Kim
In order to find out the propagation characteristics of partial discharge signals when 3 phase power cables are connected to other electric equipments such as transformers, GIS, etc., simulated experiments have been performed. Two type of connection methods in the transformer, that is Δ-Δ and Y-Y, were adopted in the modeling. As a result, it is founded that the propagation characteristics of partial discharge signals depend on the connection methods, which would be effective in the on-site partial discharge measurement.
{"title":"Partial discharge identification in 3-phase simultaneous detection for power cables","authors":"Jeongtae Kim, Jaecheol Jeong, Jihong Kim","doi":"10.1109/ICHVE.2010.5640812","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640812","url":null,"abstract":"In order to find out the propagation characteristics of partial discharge signals when 3 phase power cables are connected to other electric equipments such as transformers, GIS, etc., simulated experiments have been performed. Two type of connection methods in the transformer, that is Δ-Δ and Y-Y, were adopted in the modeling. As a result, it is founded that the propagation characteristics of partial discharge signals depend on the connection methods, which would be effective in the on-site partial discharge measurement.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"2 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129959808","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640863
Jinliang He
Switching over-voltage level plays a decisive role on the UHV equipments selection and equipment costs. This paper discussed the suppress effects of different methods. Two novel surge arresters under developing are introduced. Presently, the closing resistors are added to suppress the switching overvoltage, if low-residual arresters can be put into operation, the closing resistors need not be added.
{"title":"Deeply suppressing switching overvoltage of 1000kV ac ultra-high voltage system (invited)","authors":"Jinliang He","doi":"10.1109/ICHVE.2010.5640863","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640863","url":null,"abstract":"Switching over-voltage level plays a decisive role on the UHV equipments selection and equipment costs. This paper discussed the suppress effects of different methods. Two novel surge arresters under developing are introduced. Presently, the closing resistors are added to suppress the switching overvoltage, if low-residual arresters can be put into operation, the closing resistors need not be added.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129608686","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640846
L. Chmura, P. Cichecki, E. Gulski, J. Smit
This contribution focuses on evaluation and monitoring for the performance of the high voltage (HV) power cables. This becomes important due to two main aspects. 1) For newly installed circuits, the on-site testing is intended to reveal defects that might be produced during shipping or installation of the cable circuit. Moreover the test confirms that the whole circuit can withstand the operational voltage and prove start of defect free life-time of the power cable system by excluding any problems that may limit operation of the cable. 2) Maintenance tests represented by condition assessment tests. This kind of non-destructive tests becomes important when determining and monitoring actual condition of the cable circuit and its ability for future performances. This is done by measuring and evaluating diagnostic parameters such as dielectric loss (tand) and partial discharge.
{"title":"On-site testing and diagnosis of new and serviced aged HV power cables - evaluation based on diagnostic parameters","authors":"L. Chmura, P. Cichecki, E. Gulski, J. Smit","doi":"10.1109/ICHVE.2010.5640846","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640846","url":null,"abstract":"This contribution focuses on evaluation and monitoring for the performance of the high voltage (HV) power cables. This becomes important due to two main aspects. 1) For newly installed circuits, the on-site testing is intended to reveal defects that might be produced during shipping or installation of the cable circuit. Moreover the test confirms that the whole circuit can withstand the operational voltage and prove start of defect free life-time of the power cable system by excluding any problems that may limit operation of the cable. 2) Maintenance tests represented by condition assessment tests. This kind of non-destructive tests becomes important when determining and monitoring actual condition of the cable circuit and its ability for future performances. This is done by measuring and evaluating diagnostic parameters such as dielectric loss (tand) and partial discharge.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128990577","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640798
T. Ferreira, A. D. Germano, E. G. Costa
This work studies the feasibility of implementing a system for diagnosis in the field of electrical insulation based on ultrasonic noise and artificial neural networks. Such system, proved functional under laboratory conditions, extracts spectral information from the ultrasonic noise emitted by the corona discharges that occur in electric equipment and correlates it with degrees of pollution previously defined. To achieve this classification, artificial neural networks are employed. The results show the viability of the method in the field, but they also show that its reliability is proportional to the size and diversity of the available database.
{"title":"Ultra-sound and artificial intelligence applied to the diagnostic of insulations in the field","authors":"T. Ferreira, A. D. Germano, E. G. Costa","doi":"10.1109/ICHVE.2010.5640798","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640798","url":null,"abstract":"This work studies the feasibility of implementing a system for diagnosis in the field of electrical insulation based on ultrasonic noise and artificial neural networks. Such system, proved functional under laboratory conditions, extracts spectral information from the ultrasonic noise emitted by the corona discharges that occur in electric equipment and correlates it with degrees of pollution previously defined. To achieve this classification, artificial neural networks are employed. The results show the viability of the method in the field, but they also show that its reliability is proportional to the size and diversity of the available database.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127859113","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640781
M. Al-Suhaily, S. Meijer, J. Smit, P. Sibbald, J. Kanters, T. Tso
To ensure the high voltage gas insulated substations (GIS) reliability while maintaining maintenance costs, it is important to determine the criticality of GIS components and planning maintenance work based on the estimated criticality level. In this paper, the GIS primary system is broken down into indenture levels and subjected to the Failure Mode, Effect, and Criticality Analysis (FMECA) to estimate failures criticality for GIS components. The method is applied to one of the 380kV GIS installation in the Netherlands. The results have shown that circuit breakers have very high criticality level. Busducts and interconnecting parts, disconnectors, and SF6 bushings have high criticality level. And surge arresters have medium criticality.
{"title":"Criticality assessment of GIS components","authors":"M. Al-Suhaily, S. Meijer, J. Smit, P. Sibbald, J. Kanters, T. Tso","doi":"10.1109/ICHVE.2010.5640781","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640781","url":null,"abstract":"To ensure the high voltage gas insulated substations (GIS) reliability while maintaining maintenance costs, it is important to determine the criticality of GIS components and planning maintenance work based on the estimated criticality level. In this paper, the GIS primary system is broken down into indenture levels and subjected to the Failure Mode, Effect, and Criticality Analysis (FMECA) to estimate failures criticality for GIS components. The method is applied to one of the 380kV GIS installation in the Netherlands. The results have shown that circuit breakers have very high criticality level. Busducts and interconnecting parts, disconnectors, and SF6 bushings have high criticality level. And surge arresters have medium criticality.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121353174","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640828
B. Qi, Chengrong Li, Bibo Geng, Zhen Hao, Jinxiang Chen, Hao You, Yihong Lin
A major cause of insulation failure in GIS equipments is due to the high-voltage electrode defect, which usually occurs at the interface formed by metallic conductor, insulator and SF6. The present research is designed to diagnose and assess the severity levels of the partial discharge (PD) provoked by high-voltage electrode defect on GIS insulator surface. With the application of gradually increased voltage, long term tests were conducted on a well-established 252 kV GIS experiment platform to observe the entire evolution process of partial discharge from its very initiation till the eventual flashover. Real time measurement was also undertaken during the tests to capture the trend curve of partial discharge as a result of test time, the scatter plot, histogram, grey-scale map, and the time-frequency map of the partial discharge. The test results indicate that 1) partial discharge initiated by high-voltage electrode defects undergoes three elocutionary phases, namely, the inception phase, the developing phase and the threatening phase; 2) as partial discharge exacerbates, the phase distribution is widening and corresponding shape changes occur in the scatter plot, histogram, grey-scale map, the time-frequency map and the ultraviolet images. It is suggested that the features of phase distribution and the corresponding spectrums be used as important criterion in diagnosing and assessing the severity levels of the partial discharge triggered by high-voltage electrode defect on GIS insulator surface.
{"title":"Partial discharge severity diagnosis and assessment: a case of high-voltage electrode defect in GIS","authors":"B. Qi, Chengrong Li, Bibo Geng, Zhen Hao, Jinxiang Chen, Hao You, Yihong Lin","doi":"10.1109/ICHVE.2010.5640828","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640828","url":null,"abstract":"A major cause of insulation failure in GIS equipments is due to the high-voltage electrode defect, which usually occurs at the interface formed by metallic conductor, insulator and SF6. The present research is designed to diagnose and assess the severity levels of the partial discharge (PD) provoked by high-voltage electrode defect on GIS insulator surface. With the application of gradually increased voltage, long term tests were conducted on a well-established 252 kV GIS experiment platform to observe the entire evolution process of partial discharge from its very initiation till the eventual flashover. Real time measurement was also undertaken during the tests to capture the trend curve of partial discharge as a result of test time, the scatter plot, histogram, grey-scale map, and the time-frequency map of the partial discharge. The test results indicate that 1) partial discharge initiated by high-voltage electrode defects undergoes three elocutionary phases, namely, the inception phase, the developing phase and the threatening phase; 2) as partial discharge exacerbates, the phase distribution is widening and corresponding shape changes occur in the scatter plot, histogram, grey-scale map, the time-frequency map and the ultraviolet images. It is suggested that the features of phase distribution and the corresponding spectrums be used as important criterion in diagnosing and assessing the severity levels of the partial discharge triggered by high-voltage electrode defect on GIS insulator surface.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132413133","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640765
V. Dang, A. Beroual, C. Perrier
This paper presents the experimental results of a comparative study of mineral oils, synthetic ester oil and natural ester oils (vegetable oils) issued from different origins through the analyse of the initiation threshold voltage of streamers, their pattern and their stopping length (final length) Lf as well as the associated current and electrical charge, in a point - plane electrode arrangement submitted to a lightning impulse voltage (1.2/50 µs). It's shown that the streamers are filamentary in the different tested oils whatever the polarity of voltage. Lf is longer when the point is positive than when it's negative whatever the oil. It's is generally longer in ester oils (natural and synthetic) than in some mineral oils. When the point is negative, Lf can be ten times higher in ester oils than in mineral ones. Basing on the stopping length of streamers, the positive polarity appears as the most unfavorable one for industrial applications and the dielectric strength of mineral oils we tested are generally better (in the considered experimental conditions) than that of ester oils.
{"title":"Comparative study of streamer phenomena in mineral, synthetic and natural ester oils under lightning impulse voltage","authors":"V. Dang, A. Beroual, C. Perrier","doi":"10.1109/ICHVE.2010.5640765","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640765","url":null,"abstract":"This paper presents the experimental results of a comparative study of mineral oils, synthetic ester oil and natural ester oils (vegetable oils) issued from different origins through the analyse of the initiation threshold voltage of streamers, their pattern and their stopping length (final length) Lf as well as the associated current and electrical charge, in a point - plane electrode arrangement submitted to a lightning impulse voltage (1.2/50 µs). It's shown that the streamers are filamentary in the different tested oils whatever the polarity of voltage. Lf is longer when the point is positive than when it's negative whatever the oil. It's is generally longer in ester oils (natural and synthetic) than in some mineral oils. When the point is negative, Lf can be ten times higher in ester oils than in mineral ones. Basing on the stopping length of streamers, the positive polarity appears as the most unfavorable one for industrial applications and the dielectric strength of mineral oils we tested are generally better (in the considered experimental conditions) than that of ester oils.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131440481","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640783
T. Jiang, Jian Li, Mingying Chen, S. Grzybowski
This paper presented a novel approach to recognize ultra-high-frequency (UHF) signals of partial discharges (PDs). Four artificial insulation defect models were designed to generate PD UHF signals, which were detected by a Peano fractal antenna in experiments. Wavelet packet (WP) decomposition was used to decompose PD UHF signals into multiple scales. A group of energy parameters and fractal dimensions of PD UHF signals were computed and used as the input parameters of a support vector machine (SVM), which was used as the PD pattern classifier. For verifying the results of this approach, a back-propagation neural network (BPNN) was also used for pattern recognition of PD UHF signals. The recognition results showed that the SVM and the proposed parameters were qualified for PD pattern recognition and the SVM had advantages over the BPNN for the purpose.
{"title":"Recognition on ultra-high-frequency signals of partial discharge by support vector machine","authors":"T. Jiang, Jian Li, Mingying Chen, S. Grzybowski","doi":"10.1109/ICHVE.2010.5640783","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640783","url":null,"abstract":"This paper presented a novel approach to recognize ultra-high-frequency (UHF) signals of partial discharges (PDs). Four artificial insulation defect models were designed to generate PD UHF signals, which were detected by a Peano fractal antenna in experiments. Wavelet packet (WP) decomposition was used to decompose PD UHF signals into multiple scales. A group of energy parameters and fractal dimensions of PD UHF signals were computed and used as the input parameters of a support vector machine (SVM), which was used as the PD pattern classifier. For verifying the results of this approach, a back-propagation neural network (BPNN) was also used for pattern recognition of PD UHF signals. The recognition results showed that the SVM and the proposed parameters were qualified for PD pattern recognition and the SVM had advantages over the BPNN for the purpose.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126889728","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 : 2010-11-18DOI: 10.1109/ICHVE.2010.5640857
A. Beroual, M. Coulibaly, O. Aitken, A. Girodet
This work shows that the discharges pattern and final length, Lf, of creeping discharges depend on the amplitude and polarity of the voltage, the type of gas (mixture) and pressure similarly as in the case of the materials we investigated previously. Lf is longer when the point is positive than when it's negative; this is likely due to the influence of space charge on the electric field. Lf increases quasi-linearly with the voltage; it's reduced when the pressure is increased. Lf is shorter in SF6 than in CO2 or N2. On the other hand, the increase of SF6 content in SF6-CO2 mixture leads to a significant decrease of Lf. Therefore the addition of small concentration of SF6 in a given gas mixture improve the dielectric strength of insulating structure.
{"title":"Study of creeping discharges propagating over epoxy resin insulators in presence of different gases and mixtures","authors":"A. Beroual, M. Coulibaly, O. Aitken, A. Girodet","doi":"10.1109/ICHVE.2010.5640857","DOIUrl":"https://doi.org/10.1109/ICHVE.2010.5640857","url":null,"abstract":"This work shows that the discharges pattern and final length, L<inf>f</inf>, of creeping discharges depend on the amplitude and polarity of the voltage, the type of gas (mixture) and pressure similarly as in the case of the materials we investigated previously. L<inf>f</inf> is longer when the point is positive than when it's negative; this is likely due to the influence of space charge on the electric field. L<inf>f</inf> increases quasi-linearly with the voltage; it's reduced when the pressure is increased. L<inf>f</inf> is shorter in SF<inf>6</inf> than in CO<inf>2</inf> or N<inf>2</inf>. On the other hand, the increase of SF<inf>6</inf> content in SF<inf>6</inf>-CO<inf>2</inf> mixture leads to a significant decrease of L<inf>f</inf>. Therefore the addition of small concentration of SF<inf>6</inf> in a given gas mixture improve the dielectric strength of insulating structure.","PeriodicalId":287425,"journal":{"name":"2010 International Conference on High Voltage Engineering and Application","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116910844","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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