2019 IEEE Electrical Insulation Conference (EIC)最新文献_第3页

Modelling Transformer Core with Appropriate Boundary Conditions for Partial Discharge Studies 局部放电研究中变压器铁心适当边界条件的建模

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046571

Santosh Janaki Raman, P. Mukherjee, S. K. Panda

{"title":"Modelling Transformer Core with Appropriate Boundary Conditions for Partial Discharge Studies","authors":"Santosh Janaki Raman, P. Mukherjee, S. K. Panda","doi":"10.1109/EIC43217.2019.9046571","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046571","url":null,"abstract":"It is known that the ladder network and the distributed circuit models that are extensively employed for modelling the transformer windings for propagation of lightning and switching impulses are not valid for Partial Discharge (PD) excitation. The frequency contents of the PD necessitates a finer discretization of the winding which is offered by the multi-conductor transmission line (MTL) model. It has also been pointed out in recent literature concerning the analytical modelling of transformer windings for PD induced currents that the effect for core could be ignored. While this assumption is valid for the upper frequency content of the PD pulse where the flux is localized, the core still needs to be modelled in the lower frequencies. In this paper, the MTL model will be adopted for modelling the transformer winding, and a combination of current and charge simulation methods will be adopted to model the core. The accuracy of the charge simulation method for the core modelling will be shown in terms of the scalar potential of the grounded core. The difference between the responses of the transformer winding obtained with and without modelling the core will be elucidated in time and frequency domains.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122640611","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}

引用次数: 0

Effect of Nanofibrillated Cellulose Doping on Properties of Oil Immersed Insulating Paper during Thermal Aging 纳米纤化纤维素掺杂对油浸绝缘纸热老化性能的影响

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046636

Yang Mo, R. Liao, Lijun Yang, Yuan Yuan

引用次数: 0

Transformer Insulation Degree of Polymerization Estimation through Adaptive Neuro Fuzzy Inference System Approach 基于自适应神经模糊推理系统的变压器绝缘聚合度估计

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046632

Edwell T. Mharakurwa, G. Nyakoe, A. Akumu

{"title":"Transformer Insulation Degree of Polymerization Estimation through Adaptive Neuro Fuzzy Inference System Approach","authors":"Edwell T. Mharakurwa, G. Nyakoe, A. Akumu","doi":"10.1109/EIC43217.2019.9046632","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046632","url":null,"abstract":"The useful life of a power transformer is linked to the integrity of its solid (cellulosic) insulation. The insulation deterioration is time dependent and is influenced by varying temperatures, moisture, oxygen, oil conditions and loading profiles. Accordingly, once the solid insulation state is compromised, its dielectric and mechanical properties are not recoverable. Thus, longevity in service of a power transformer can only be achieved by incessant monitoring and assessing the credibility of its insulation system. The tensile strength of the solid insulation can be indicated by determining the degree of polymerization of the paper. Consequently, the degree of polymerization is a key indicator of the insulation status that correlates well with the transformer remnant life. Since degree of polymerization measurement is an intrusive test involving transformer disassembling, utilities have opted to the use of furans concentration in the oil as a way of determining the degree of polymerization of transformer solid insulation. However, these furans and degree of polymerization correlations are based on mathematical models. This paper introduces an adaptive neuro fuzzy model to estimate the degree of polymerization of a mineral oil-immersed power transformer based on furan content and CO2/CO gas concentration ratio in the insulation system. Practical data from numerous power transformers of different lifespans subjected to different operating regimes have been used to validate the accuracy and credibility of the established adaptive neuro fuzzy model. Compared to the conventional models, the results show that the proposed model is effective in estimating the degree of polymerization of transformer solid insulation.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121886186","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}

引用次数: 2

A Novel Nonlinearly Equivalent Circuit Model for Calculating Electric Fields Along the Stator End-winding of HV Rotating Machine 一种计算高压旋转电机定子端部电场的非线性等效电路模型

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046598

Ping Liu, Xuezhong Liu, Yue Zhang, Zhiming Liang, Bo Hu

{"title":"A Novel Nonlinearly Equivalent Circuit Model for Calculating Electric Fields Along the Stator End-winding of HV Rotating Machine","authors":"Ping Liu, Xuezhong Liu, Yue Zhang, Zhiming Liang, Bo Hu","doi":"10.1109/EIC43217.2019.9046598","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046598","url":null,"abstract":"In order to study the performances of electric potential or electric field distribution along the stator bar end-winding, a novel equivalent circuit model was proposed to calculate the electric field distribution along the surface of stress grading system in this paper. Compared with the conventional equivalent circuit which just described the stress grading tape (SGT) and groundwall insulation, this model was more complex and also took the air gap into account. Based on the proposed equivalent circuit, the transient potential and electric field distributions along the three-segment SGTs, usually named as medium, medium-high and high resistance coating respectively, of a rated 24 kV class hydro-generator stator bar end-winding were simulated. The simulation results show that the transient potential or electric field at each point along the three-segment SGTs has a significant phase or time difference (or delay) with any other location at a moment. This novel proposed equivalent circuit model should be adequate to optimize SG system of stator end-winding for the high voltage rotating machines.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116209331","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}

引用次数: 1

Transformer Remnant Life Estimation and Asset Management model based on Insulation Stress Assessment 基于绝缘应力评估的变压器剩余寿命估算及资产管理模型

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046526

Edwell T. Mharakurwa, G. Nyakoe, A. Akumu

{"title":"Transformer Remnant Life Estimation and Asset Management model based on Insulation Stress Assessment","authors":"Edwell T. Mharakurwa, G. Nyakoe, A. Akumu","doi":"10.1109/EIC43217.2019.9046526","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046526","url":null,"abstract":"The performance and useful life expectancy of a power transformer generally depends on the condition of oil-impregnated paper insulation system that has a finite life span. End of technical life of a power transformer is reached when some of the insulation diagnostic characteristics drop to a level where further operation is unacceptable. Thus, recurrent evaluation of the transformer insulation system diagnostics enhances better estimation of transformer residual life. However, being a function of voluminous conflicting attributes, the design feature, changing operating conditions, and different maintenance strategies, a flawless affirmation of the criteria governing the transformer remnant life estimation is a very complex issue. Power transformer operational condition that can be mirrored by criticality of ageing and fault stress levels has substantial impact on its residual life estimation. This paper explores the possibility of developing a remnant life estimation and asset management decision model based on diagnostics of transformer insulation characteristics. The proposed model is developed upon the integration of the fuzzy logic diagnostic tool and the fuzzy logic remnant life mapping model. The diagnostic details are signified by fuzzy rules for an accurate assessment to reach a defined outcome in terms of fault stress level and energy of faulting, ageing stresses and transformer condition. A multicriteria analysis was used in developing the model whereby the outcome of the model is achieved by including the combined effect of individual sub outcomes using fuzzification of all the employed attributes. The developed remnant life model is validated using data collected from several in-service mineral oil immersed transformers. Results show that the proposed model provides an approximate but practical means of remnant life estimation and asset management decision.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122440176","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}

引用次数: 3

Research on Transformer Condition-based Maintenance Optimization Based on Live Detection 基于带电检测的变压器状态维护优化研究

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046594

Jieqing Deng, Chao Wei, Jiansheng Li, Houying Li, Guangyao Wang, Youyuan Wang

{"title":"Research on Transformer Condition-based Maintenance Optimization Based on Live Detection","authors":"Jieqing Deng, Chao Wei, Jiansheng Li, Houying Li, Guangyao Wang, Youyuan Wang","doi":"10.1109/EIC43217.2019.9046594","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046594","url":null,"abstract":"At present, the maintenance strategy for transformers mainly focus on the optimization of maintenance mode and time, while the influence of state parameter detection mode on power grid is often ignored. Considering the popularization and application of live detection technology, an optimization method of transformer state maintenance strategy based on live detection is proposed, which considers the economy and reliability. Firstly, on the basis of defining the key detection parameters of power outage test, an alternative analysis model based on online oil chromatographic data is constructed for replacing power outage test parameters. And then the average value of absolute error is introduced as an evaluation index to determine whether to replace or extend the power outage test, which is called the formulation of optimal scheme. Finally, a quantitative model of acquisition risk of state parameters and transformer failure risk is established with the comprehensive optimization of reliability and economy as decision variables. The example of maintenance decision-making for a 220kV transformer shows that the state maintenance based on live detection can reduce the maintenance cost on the principle of ensuring safe and reliable operation of transformer.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116328181","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}

引用次数: 1

Partial Discharge Detection Strategies under Fast Rise Time Voltages Generated by Wide-bandgap Semiconductor Devices 宽禁带半导体器件快速上升电压下的局部放电检测策略

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046572

Zhuo Wei, Haoyang You, Risha Na, Jin Wang

{"title":"Partial Discharge Detection Strategies under Fast Rise Time Voltages Generated by Wide-bandgap Semiconductor Devices","authors":"Zhuo Wei, Haoyang You, Risha Na, Jin Wang","doi":"10.1109/EIC43217.2019.9046572","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046572","url":null,"abstract":"Wide-bandgap (WBG) semiconductor device is one of the leading contenders for the next generation semiconductor device. Its advantages include but not limited to: higher voltage rating, switching speed and frequency. However, when electrical applications are driven by WBG devices, the voltage stress is inevitably changed. To be more precise, the voltage stress is more likely to be enhanced based on the premature failures observed for various applications driven by WBG devices. As has been well accepted, partial discharge (PD) is considered as the main cause for insulation failure in high frequency equipment. Thus, it is necessary to study PD behaviors under the new stress introduced by WBG device. However, the issue is inherently challenging due to the nature of the equipment under test and the extremely high dv/dt (fast rise time) square-wave voltage introduced. Huge charging/discharging current would be seen at the rising/falling edges of the square-wave pulse train. The magnitude of the charging/discharging current can be hundreds of or even thousands of times larger than that of PD pulse current. In some cases, even in frequency domain, the PD pulse current would be masked by the charging/discharging current. In this paper, a summary is made on past research related to PD detection strategies under fast rise time square-wave voltage or impulse voltage. Their advantages and disadvantages would be introduced to provide a full picture about this issue for future researchers when the need of PD detection under fast rise time excitations arises.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"194 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125284139","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}

引用次数: 6

Additive effect on dielectric spectra of crosslinked polyethylene (XLPE) used in nuclear power plants 核电厂用交联聚乙烯(XLPE)介电光谱的加性效应

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046600

S. V. Suraci, D. Fabiani, Chuanyang Li

引用次数: 8

Partial Discharge Characterisation of Stator Windings Taken from a 50-year-old Norwegian Hydrogenerator 一台50年历史的挪威水轮发电机定子绕组局部放电特性

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046527

G. Berg, E. Eberg, S. Hvidsten

{"title":"Partial Discharge Characterisation of Stator Windings Taken from a 50-year-old Norwegian Hydrogenerator","authors":"G. Berg, E. Eberg, S. Hvidsten","doi":"10.1109/EIC43217.2019.9046527","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046527","url":null,"abstract":"This paper presents results from laboratory measurements of partial discharge (PD) activity in stator bars taken from a 95 MVA hydrogenerator after 52 years in service. The generator has previously been subjected to off-line condition monitoring including partial discharge (PD) testing at both 0.1 and 50 Hz, and on-line PD monitoring at 50 Hz. Stator bars were selected from representative positions along the winding, including both the neutral point and high voltage side. Initial PD testing has been performed at a fixed voltage level (9 kV/1.2 U0) to assess the current state of the stator bars. Based on the PD measurements a comprehensive set of characteristic discharge data has been found for 161 stator bars retrieved from the decommissioned hydro generator. The selection of measured data for presentation in this paper is based on the phase and position of the bars in the generator providing an extensive PD activity mapping of the generator. The test results show a large variation in discharge activity among the stator bars. However, using statistical analysis it is not possible to distinguish between service-aged bars taken from high and low electric stress regions.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128006517","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}

引用次数: 5

Classification of Insulating Liquids Thermal Treatment Using Infrared Spectroscopy and Multivariate Statistical Method 利用红外光谱和多元统计方法对绝缘液体热处理进行分类

2019 IEEE Electrical Insulation Conference (EIC) Pub Date : 2019-06-01 DOI: 10.1109/EIC43217.2019.9046556

P. Prosr, R. Polanský, J. Pihera, P. Hahn

{"title":"Classification of Insulating Liquids Thermal Treatment Using Infrared Spectroscopy and Multivariate Statistical Method","authors":"P. Prosr, R. Polanský, J. Pihera, P. Hahn","doi":"10.1109/EIC43217.2019.9046556","DOIUrl":"https://doi.org/10.1109/EIC43217.2019.9046556","url":null,"abstract":"Paper is focused on the investigation of the possibility of using statistical methods as discriminant analysis and principal component analysis for a classification of the aging of insulating material. The Statistical method was used in combination with Fourier Transform Infrared Spectroscopy results (FT-IR). The investigation was carried out on thermally aged mineral oil samples. The tested oil was exposed to thermal treatment at a temperature of 130°C for times ranging from 24 to 572 hours. Infrared spectra were measured at predefined times of aging using transmission technique in the middle area of the infrared electromagnetic spectrum. Program TQ Analyst was used for other evaluation of changes in measured infrared spectra and the possibility of their separation according to aging times. Based on the experiment performed, discriminability of individual levels of aging based on infrared spectra (IR) measurements was identified even in cases of minimum spectra differences. Combination of FT-IR measurement together with the application of multivariate statistical methods seems to be promising in possible application to aging level identification and automatization of the process of evaluation.","PeriodicalId":340602,"journal":{"name":"2019 IEEE Electrical Insulation Conference (EIC)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114519380","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}

引用次数: 1