Pub Date : 2018-09-01DOI: 10.1109/CMD.2018.8535857
Toshihiro Takahashi
Partial discharge (PD) measurement is a powerful technique for the insulation diagnosis and precise asset management of electric power apparatus. However, PD occurs sometimes not continuously, rather with very low repetition rate in its inception stage. In that case, it is difficult in on-site PD measurement and diagnosis, because the pulses of very low repetition rate are difficult to produce any finger print such as phase resolved PD pattern (PRPD pattern). On the contrary, the continuously generated pulse signals obtained at the on-site PD measurement sometimes do not come from PD generated at the internal electrical insulation layer but outside of the apparatus such as a surface of the bushing, an edge of a metallic part of the apparatus which is installed near the objective apparatus. These signals coming not from the intended apparatus sometimes leads incorrect diagnostic results. Thus, the discrimination methodology of PD signals occurring in the intended apparatus is important for the accurate PD measurement and diagnosis. This paper discusses the discrimination methodology for the PD measurement at cable terminations and joints.
{"title":"Methodology of on-site Precise Partial Discharge Measurement for Cable Terminations and Joints","authors":"Toshihiro Takahashi","doi":"10.1109/CMD.2018.8535857","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535857","url":null,"abstract":"Partial discharge (PD) measurement is a powerful technique for the insulation diagnosis and precise asset management of electric power apparatus. However, PD occurs sometimes not continuously, rather with very low repetition rate in its inception stage. In that case, it is difficult in on-site PD measurement and diagnosis, because the pulses of very low repetition rate are difficult to produce any finger print such as phase resolved PD pattern (PRPD pattern). On the contrary, the continuously generated pulse signals obtained at the on-site PD measurement sometimes do not come from PD generated at the internal electrical insulation layer but outside of the apparatus such as a surface of the bushing, an edge of a metallic part of the apparatus which is installed near the objective apparatus. These signals coming not from the intended apparatus sometimes leads incorrect diagnostic results. Thus, the discrimination methodology of PD signals occurring in the intended apparatus is important for the accurate PD measurement and diagnosis. This paper discusses the discrimination methodology for the PD measurement at cable terminations and joints.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"26 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75425923","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}
The space charges accumulation between HVDC cable and accessory insulation will accelerate degradation and breakdown of the cable system, endanger the safety of the power grid. As is known that conductivity mismatch of cross-linked polyethylene (XLPE) and ethylene-propylene-diene terpolymer (EPDM) is the main reason for the charges accumulation in the interface. To investigate the influence of EPDM conductivity on the interface behaviors of XLPE/EPDM, In this paper, high field conductivity of two kind of EPDM and XLPE were tested at −5 kV/mm, −10 kV/mm, −20 kV/mm, −30 kV/mm, −40 kV/mm, −50 kV/mm and −60 kV/mm, and the space charges distribution of XLPE/EPDM interface was tested by pressure wave propagation (PWP) at −10kV/mm, −20kV/mm and −30kV/mm. It is shown that, when the conductivity of XLPE is lower than EPDM, the interface charge is positive; On the contrary, when the conductivity of XLPE is higher than EPDM, the interface charge is negative, and the interface charges density increases as the electric field rise. The experimental results are consistent with the interface charge density calculated based on the Maxwell-Wagner theory.
{"title":"Interface Charge Behaviors between XLPE and EPDM with Different Conductivity","authors":"Dong Li, Zhien Zhu, Liming Yang, Hao Zeng, K. Gao, Lixin Xu","doi":"10.1109/CMD.2018.8535642","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535642","url":null,"abstract":"The space charges accumulation between HVDC cable and accessory insulation will accelerate degradation and breakdown of the cable system, endanger the safety of the power grid. As is known that conductivity mismatch of cross-linked polyethylene (XLPE) and ethylene-propylene-diene terpolymer (EPDM) is the main reason for the charges accumulation in the interface. To investigate the influence of EPDM conductivity on the interface behaviors of XLPE/EPDM, In this paper, high field conductivity of two kind of EPDM and XLPE were tested at −5 kV/mm, −10 kV/mm, −20 kV/mm, −30 kV/mm, −40 kV/mm, −50 kV/mm and −60 kV/mm, and the space charges distribution of XLPE/EPDM interface was tested by pressure wave propagation (PWP) at −10kV/mm, −20kV/mm and −30kV/mm. It is shown that, when the conductivity of XLPE is lower than EPDM, the interface charge is positive; On the contrary, when the conductivity of XLPE is higher than EPDM, the interface charge is negative, and the interface charges density increases as the electric field rise. The experimental results are consistent with the interface charge density calculated based on the Maxwell-Wagner theory.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"13 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75570468","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535848
Hongmei Wang, Jiangrong Cheng, Dengwei Ding, Weidong Liu, Liang He
the paper proposes a new detection method for partial discharge in transformer. Different from conventional UHF method, which mainly detects electromagnetic wave motivated by discharge, the proposed method detects current pulse signal excited by discharge in UHF band from bushing tap grounding wire. An experiment is performed to study feasibility of the proposed method and to make a contrast with conventional UHF method. It is concluded that, though the sensitivity of proposed method is a little lower compared to internal antenna UHF method, it is still enough to detect partial discharge effectively, and the proposed method is easy to operate and out of problems such as seal which internal UHF method owns. The proposed method offers a relatively practical solution to on-site detection for partial discharge in transformer.
{"title":"A feasibility study on bushing tap UHF sensing method for partial discharge in transformer","authors":"Hongmei Wang, Jiangrong Cheng, Dengwei Ding, Weidong Liu, Liang He","doi":"10.1109/CMD.2018.8535848","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535848","url":null,"abstract":"the paper proposes a new detection method for partial discharge in transformer. Different from conventional UHF method, which mainly detects electromagnetic wave motivated by discharge, the proposed method detects current pulse signal excited by discharge in UHF band from bushing tap grounding wire. An experiment is performed to study feasibility of the proposed method and to make a contrast with conventional UHF method. It is concluded that, though the sensitivity of proposed method is a little lower compared to internal antenna UHF method, it is still enough to detect partial discharge effectively, and the proposed method is easy to operate and out of problems such as seal which internal UHF method owns. The proposed method offers a relatively practical solution to on-site detection for partial discharge in transformer.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"35 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73800344","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535704
H. Morooka, A. Yamagishi, K. Kawamura, H. Kojima, N. Hayakawa
The surface chemical properties of aged pressboards (PBs) were evaluated to investigate the mechanism behind the increasing tendency of electrostatic charges for diagnosing power transformers. The PBs were taken from several aged transformers, and their surface elemental composition and chemical structures were measured by X-ray photoelectron spectroscopy. The PBs properties were measured after being washed by an organic solvent to remove impregnated mineral oil. Carbon (C) and oxygen (O) atoms were mostly observed on virgin PBs surfaces; these are the atoms that compose cellulose polymer, the main component of kraft pulp. In contrast, sulfur (S) and calcium (Ca) atoms were observed on the surfaces of aged PBs in addition to the C and O atoms. Moreover, the surface densities of the Ca atoms had a good correlation with those of the S atoms. While we detected no S atoms inside the aged PBs, we observed almost the same amount of Ca atoms as in the virgin PBs. Mineral oils mainly consist of hydrocarbons, with very small amounts of components such as sulfur compounds derived from crude oil. Heat stress degrades these sulfur compounds. On the other hand, PBs made of kraft pulp contain a very small amount of metal ions, such as Ca ions. We conclude that S atoms observed on aged PB surfaces are a part of the aged sulfur compounds adsorbed from the mineral oil. The adsorption of aged sulfur compounds induced the migration of Ca ions from the inside of the PBs to the surface, which caused the surface density of the Ca ions to increase. This suggests that the accumulation of Ca ions along with the sulfur compounds led to the increasing tendency of electrostatic charges in aged PBs.
{"title":"Mechanism behind Increasing Electrostatic Charging Tendency in Aged Mineral-Oil-Immersed Pressboards","authors":"H. Morooka, A. Yamagishi, K. Kawamura, H. Kojima, N. Hayakawa","doi":"10.1109/CMD.2018.8535704","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535704","url":null,"abstract":"The surface chemical properties of aged pressboards (PBs) were evaluated to investigate the mechanism behind the increasing tendency of electrostatic charges for diagnosing power transformers. The PBs were taken from several aged transformers, and their surface elemental composition and chemical structures were measured by X-ray photoelectron spectroscopy. The PBs properties were measured after being washed by an organic solvent to remove impregnated mineral oil. Carbon (C) and oxygen (O) atoms were mostly observed on virgin PBs surfaces; these are the atoms that compose cellulose polymer, the main component of kraft pulp. In contrast, sulfur (S) and calcium (Ca) atoms were observed on the surfaces of aged PBs in addition to the C and O atoms. Moreover, the surface densities of the Ca atoms had a good correlation with those of the S atoms. While we detected no S atoms inside the aged PBs, we observed almost the same amount of Ca atoms as in the virgin PBs. Mineral oils mainly consist of hydrocarbons, with very small amounts of components such as sulfur compounds derived from crude oil. Heat stress degrades these sulfur compounds. On the other hand, PBs made of kraft pulp contain a very small amount of metal ions, such as Ca ions. We conclude that S atoms observed on aged PB surfaces are a part of the aged sulfur compounds adsorbed from the mineral oil. The adsorption of aged sulfur compounds induced the migration of Ca ions from the inside of the PBs to the surface, which caused the surface density of the Ca ions to increase. This suggests that the accumulation of Ca ions along with the sulfur compounds led to the increasing tendency of electrostatic charges in aged PBs.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"1 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91225617","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535602
Guanglei Huang, W. Cao, Xiaolei Xie, Zilong Li, Zhe Li, G. Sheng
The classification of partial discharge is of significance to diagnose the defects in high voltage cable systems. To improve the insulation defect classification accuracy at DC cross linked polyethylene(XLPE) cables, a new method used for PD images classification based on convolutional deep belief network (CDBN) is proposed in this paper. Firstly, four kinds of defects in XLPE cables are designed and tested under DC voltage. The q-Δt-n image is constructed based on PD signal collected by HFCT. Then the diagnostic CDBN model is constructed to extract the high-level detailed feature of q-Δt-n images with Gaussian visible units. Finally, classification experiments with CDBN, deep belief network(DBN), support vector machine(SVM) and backpropagation neural network(BPNN) is conducted. The experiment results show that the proposed method has higher classification accuracy of insulation defect diagnosis.
{"title":"Classification of Partial Discharge Images within DC XLPE Cables Based on Convolutional Deep Belief Network","authors":"Guanglei Huang, W. Cao, Xiaolei Xie, Zilong Li, Zhe Li, G. Sheng","doi":"10.1109/CMD.2018.8535602","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535602","url":null,"abstract":"The classification of partial discharge is of significance to diagnose the defects in high voltage cable systems. To improve the insulation defect classification accuracy at DC cross linked polyethylene(XLPE) cables, a new method used for PD images classification based on convolutional deep belief network (CDBN) is proposed in this paper. Firstly, four kinds of defects in XLPE cables are designed and tested under DC voltage. The q-Δt-n image is constructed based on PD signal collected by HFCT. Then the diagnostic CDBN model is constructed to extract the high-level detailed feature of q-Δt-n images with Gaussian visible units. Finally, classification experiments with CDBN, deep belief network(DBN), support vector machine(SVM) and backpropagation neural network(BPNN) is conducted. The experiment results show that the proposed method has higher classification accuracy of insulation defect diagnosis.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"40 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90299715","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535655
Charbel Antoun
This paper aims to explore the various failure modes associated with High Voltage Circuit Breakers and Power Transformers within transmission and subtransmission electricity networks and identify the online monitoring requirements to ensure effective early detection of issues. This would enable system operators to act appropriately to prevent unexpected failures. These requirements in the context of the capabilities and limitations in currently available Online Monitoring Technologies will also be discussed.
{"title":"High Voltage Circuit Breaker and Power Transformer Failure Modes and Their Detection","authors":"Charbel Antoun","doi":"10.1109/CMD.2018.8535655","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535655","url":null,"abstract":"This paper aims to explore the various failure modes associated with High Voltage Circuit Breakers and Power Transformers within transmission and subtransmission electricity networks and identify the online monitoring requirements to ensure effective early detection of issues. This would enable system operators to act appropriately to prevent unexpected failures. These requirements in the context of the capabilities and limitations in currently available Online Monitoring Technologies will also be discussed.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"10 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88863079","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535828
Feng Ji, Qing Xu, Zhengqi Tian, Jin Bao
Considering the problems that Black box testing method for watt-hour meter cannot implement branch path traversal of the watt-hour meter software, and can't provide EEPROM data error tolerance evaluation of the watt-hour meter, also including the fact that watt-hour meter data storage unit EEPROM preserves running parameters of watt-hour meters, this paper proposes a new type of watt-hour meter white-box testing method based on EEPROM read and write. The new test method rewrites the parameters in EEPROM, which can implement branch path traversal of the watt-hour meter software, and avoid the branches path missing of the black box test. At the same time, the new test method can realize the fault tolerance evaluation of watt-hour meter software. Through the construction and integration of the new test platform, the watt-hour meter software can be tested automatically by the white-box test method, thus the test efficiency is greatly improved. As this method is applicable to the reliability test of the watt-hour meter, it can obtain better economic benefits compared with the black box testing method. The implementation of the new method in this paper have a certain reference value as to improve the reliability and fault tolerance of the watt-hour meter.
{"title":"A New White Box Test Method Applying to Watt-hour Meter Based on EEPROM Read and Write Data","authors":"Feng Ji, Qing Xu, Zhengqi Tian, Jin Bao","doi":"10.1109/CMD.2018.8535828","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535828","url":null,"abstract":"Considering the problems that Black box testing method for watt-hour meter cannot implement branch path traversal of the watt-hour meter software, and can't provide EEPROM data error tolerance evaluation of the watt-hour meter, also including the fact that watt-hour meter data storage unit EEPROM preserves running parameters of watt-hour meters, this paper proposes a new type of watt-hour meter white-box testing method based on EEPROM read and write. The new test method rewrites the parameters in EEPROM, which can implement branch path traversal of the watt-hour meter software, and avoid the branches path missing of the black box test. At the same time, the new test method can realize the fault tolerance evaluation of watt-hour meter software. Through the construction and integration of the new test platform, the watt-hour meter software can be tested automatically by the white-box test method, thus the test efficiency is greatly improved. As this method is applicable to the reliability test of the watt-hour meter, it can obtain better economic benefits compared with the black box testing method. The implementation of the new method in this paper have a certain reference value as to improve the reliability and fault tolerance of the watt-hour meter.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"35 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78742178","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535666
N. Phloymuk, P. Nimsanong, N. Phumipunepon, S. Potivejkul, T. Wiangtong, N. Pattanadech
the aim of this paper is to describe the dielectric loss tangent (tan δ) behaviors of the stator winding insulation of the 14.5 MVA 11kV synchronous machine from 2014–2017. This machine is still operated up to now. The tan δ values at different test voltages was measured and recorded. It was found that the sharp increase in tan δ values gave the sign of a significant degree of contamination and damage on the insulation surface which was proved by inspection. From the investigation the tan δ measurements is one of the effective ways to monitor and evaluate the insulation conditions of the stator insulation. The analysis and discussion of the existed problem of the synchronous machine are also included in this paper.
{"title":"The Dissipation Factor (tan δ) Monitoring of A Stator Winding Insulation of A Synchronous Machine","authors":"N. Phloymuk, P. Nimsanong, N. Phumipunepon, S. Potivejkul, T. Wiangtong, N. Pattanadech","doi":"10.1109/CMD.2018.8535666","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535666","url":null,"abstract":"the aim of this paper is to describe the dielectric loss tangent (tan δ) behaviors of the stator winding insulation of the 14.5 MVA 11kV synchronous machine from 2014–2017. This machine is still operated up to now. The tan δ values at different test voltages was measured and recorded. It was found that the sharp increase in tan δ values gave the sign of a significant degree of contamination and damage on the insulation surface which was proved by inspection. From the investigation the tan δ measurements is one of the effective ways to monitor and evaluate the insulation conditions of the stator insulation. The analysis and discussion of the existed problem of the synchronous machine are also included in this paper.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"127 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85724572","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535906
Kyu-Hoon Park, Ho-Yun Lee, M. Asif, Bang-wook Lee
As the multi-terminal HVDC systems are expanding, the needs for a HVDC circuit breaker is being enhanced to eliminate the adverse effects of a single pole fault on the whole system. However, there are challenges of dc interrupting that is due to the absence of the natural current zero point and the large rate of fault current (di / dt), which results in enormous interrupting energy. Therefore, the suitable circuit breaker topology that satisfy dc interrupting requirements have been widely studied. The passive resonance circuit breaker (PRCB) is one of the circuit breaker topologies that have been considered for HVDC system, and it is necessary to investigate the arc characteristics occurring in the main circuit breaker during opening operation. In this paper, a dc current source that generates a current pulse using semiconductor device IGBT switch and pre-charged capacitor was modeled, and Mayr black box model was used for analysis of arc characteristics. Unlike the conventional current source that generates the dc arc current using the L and C, the new current source can be arbitrarily selected for the current shape and the current slope without hardware modification and was used for measuring the steady state and transient state voltage-current characteristics of the switching arc. The black box Mayr model parameter values were calculated elaborately through the enhanced current source and the Levenberg-Marquardt Algorithm (LMA) widely used in the optimization technique was applied to the Mayr model to optimize the parameter values.
{"title":"Investigation of Arc Behavior in HVDC LC Resonance Circuit Breaker Using Flexible Pulsed DC-Source","authors":"Kyu-Hoon Park, Ho-Yun Lee, M. Asif, Bang-wook Lee","doi":"10.1109/CMD.2018.8535906","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535906","url":null,"abstract":"As the multi-terminal HVDC systems are expanding, the needs for a HVDC circuit breaker is being enhanced to eliminate the adverse effects of a single pole fault on the whole system. However, there are challenges of dc interrupting that is due to the absence of the natural current zero point and the large rate of fault current (di / dt), which results in enormous interrupting energy. Therefore, the suitable circuit breaker topology that satisfy dc interrupting requirements have been widely studied. The passive resonance circuit breaker (PRCB) is one of the circuit breaker topologies that have been considered for HVDC system, and it is necessary to investigate the arc characteristics occurring in the main circuit breaker during opening operation. In this paper, a dc current source that generates a current pulse using semiconductor device IGBT switch and pre-charged capacitor was modeled, and Mayr black box model was used for analysis of arc characteristics. Unlike the conventional current source that generates the dc arc current using the L and C, the new current source can be arbitrarily selected for the current shape and the current slope without hardware modification and was used for measuring the steady state and transient state voltage-current characteristics of the switching arc. The black box Mayr model parameter values were calculated elaborately through the enhanced current source and the Levenberg-Marquardt Algorithm (LMA) widely used in the optimization technique was applied to the Mayr model to optimize the parameter values.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"93 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85792651","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 : 2018-09-01DOI: 10.1109/CMD.2018.8535625
Natsumi Sato, Kotaro Suzuki, Ushio Chiba, H. Miyake, Y. Tanaka, T. Okumura, S. Kawakita, M. Takahashi, K. Koga
The dielectric characteristics of the surface material of the spacecraft, such as secondary electron emission (SEE) and photoelectron emission (PE), are required for high reliability of spacecraft generation. Those materials are deteriorated due to radioactive rays irradiation on orbit. Those values may be changed from the situation. When we want to estimate surface changing at the end of life (EOL) of satellite with accuracy, we need to give values of PE and SEE at EOL situation. In this report, we irradiated the proton beam to insulating materials and measured PE on the aged sample. We examined the relationship between the irradiation dose and PE.
{"title":"Photoelectron Emission on Polyimide Films Irradiated by Proton","authors":"Natsumi Sato, Kotaro Suzuki, Ushio Chiba, H. Miyake, Y. Tanaka, T. Okumura, S. Kawakita, M. Takahashi, K. Koga","doi":"10.1109/CMD.2018.8535625","DOIUrl":"https://doi.org/10.1109/CMD.2018.8535625","url":null,"abstract":"The dielectric characteristics of the surface material of the spacecraft, such as secondary electron emission (SEE) and photoelectron emission (PE), are required for high reliability of spacecraft generation. Those materials are deteriorated due to radioactive rays irradiation on orbit. Those values may be changed from the situation. When we want to estimate surface changing at the end of life (EOL) of satellite with accuracy, we need to give values of PE and SEE at EOL situation. In this report, we irradiated the proton beam to insulating materials and measured PE on the aged sample. We examined the relationship between the irradiation dose and PE.","PeriodicalId":6529,"journal":{"name":"2018 Condition Monitoring and Diagnosis (CMD)","volume":"19 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88618819","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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