2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)最新文献_第5页

Life estimation of transformer insulation under repeated impulses 重复脉冲作用下变压器绝缘寿命估算

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737522

S. Balaji, S. Usa

{"title":"Life estimation of transformer insulation under repeated impulses","authors":"S. Balaji, S. Usa","doi":"10.1109/CATCON.2013.6737522","DOIUrl":"https://doi.org/10.1109/CATCON.2013.6737522","url":null,"abstract":"Oil Impregnated Paper (OIP) is commonly used dielectric material in transformer windings. The most of the transformer winding failures are due to breakdown of dielectric material. The breakdown mechanism of composite dielectric undergoes gradual degradation in nature. OIP is subjected to rapid degradation when it is subjected to overvoltages. The severity of the degradation depends on steepness of the waveshape. It is necessary to analyze the characteristics of OIP for varying wavefronts (tf) ranging from lightning to Very Fast Transient Overvoltages (VFTO). V-N characteristic provides detailed information on degradation with respect to repeated overvoltages. The time interval (At) between the successive impulse overvoltages plays a vital role in determining the V-N characteristics. In this paper, an attempt has been made to predict the V-N characteristics for any (tf) and (At) using exponential model and the results are validated with test waveshape of 0.78/50 μs with Δt = 2s. Apart from the V-N characteristics of OIP, the remaining life of the transformer can be estimated from degree of polymerization (DP) using Ekenstam second order equation.","PeriodicalId":290479,"journal":{"name":"2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125379498","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: 8

Analysis of variations in measured recovery voltage peaks due to presence of moisture in insulation of power transformers 分析由于电力变压器绝缘中存在湿气所测得的恢复电压峰值的变化

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737494

S. Mallik, P. Purkait, N. Mohandas, S. V. Kulkarni

引用次数: 2

Understanding the correlation between dielectric response measurement results and equivalent circuit pole locations of a transformer oil paper insulation system 了解变压器油纸绝缘系统的介电响应测量结果与等效电路极位之间的关系

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737493

S. K. Ojha, P. Purkait, D. Mukherjee, Sivaji Chakravorti

{"title":"Understanding the correlation between dielectric response measurement results and equivalent circuit pole locations of a transformer oil paper insulation system","authors":"S. K. Ojha, P. Purkait, D. Mukherjee, Sivaji Chakravorti","doi":"10.1109/CATCON.2013.6737493","DOIUrl":"https://doi.org/10.1109/CATCON.2013.6737493","url":null,"abstract":"Lifetime of a transformer is determined by the condition of its oil paper insulation. Presence of moisture in the insulation reduces the dielectric strength and hence the remaining life. During the entire period of operation of transformer, moisture diffusion between oil and paper takes place, this causes the transformer to operate in a state of thermodynamic non equilibrium. Paper insulation of a transformer serves as the prime source of water in transformer. Oil moisture content can be directly measured using Karl Fischer Titration method. But determination of paper moisture will involve the collecting of paper sample from the transformer which will make the test destructive. Hence paper moisture is estimated from the standard equilibrium curves. Recently, pole values determined from the traditional linear model of the insulation structure have been used to serve as a basic guide for assessing the condition of oil paper insulation system of a transformer. Theoretically the RC branches of the linear equivalent model with lower time constant reflects the condition of insulation of oil and higher time constant branch reflects the condition of solid insulation. From this basic idea pole location of different branches are calculated and reported in this article. This present work attempts to assess the condition of insulation by locating position of the poles, and how pole locations vary with paper and oil moisture as well as temperature.","PeriodicalId":290479,"journal":{"name":"2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128417225","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

Simulation of Bewley's lattice diagram using MATLAB 用MATLAB仿真Bewley晶格图

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737466

Brajagopal Datta, S. Chatterjee

引用次数: 7

Experience with transformer interaction with low amplitude high oscillatory switching transients in a power utility network 有在电力网络中变压器与低幅高振荡开关瞬态相互作用的经验

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737471

Poulomi Mitra, Sreejeet Ghosh, A. De, A. Chakrabarti

引用次数: 0

Detection of simultaneous unbalanced under-voltage and broken rotor fault in induction motor 感应电动机欠压不平衡和转子断动同时故障的检测

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737472

S. Sridhar, K. Rao

引用次数: 6

Characterization of short circuit faults and incipient insulation degradation between stator winding turns of induction motor 感应电动机定子绕组匝间短路故障及早期绝缘退化的表征

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737473

Santanu Das, P. Purkait, S. Chakravorti

{"title":"Characterization of short circuit faults and incipient insulation degradation between stator winding turns of induction motor","authors":"Santanu Das, P. Purkait, S. Chakravorti","doi":"10.1109/CATCON.2013.6737473","DOIUrl":"https://doi.org/10.1109/CATCON.2013.6737473","url":null,"abstract":"The aim of this work is to present a method to discriminate between dead short circuit and incipient or partial short circuit in induction motor stator winding when the dead short circuit conditions are introducing unbalance in three phase stator currents similar to the latter case and that too under different loading conditions. Unbalance in motor current may also be introduced by unbalance in supply voltage. Any unbalance in the motor currents caused either by fault or supply voltage unbalance or even inherent asymmetry in motor circuit makes negative sequence current to crop up. This paper presents a scheme to estimate the magnitude of negative sequence current introduced by motor faults only. Negative sequence current analysis employing Power Decomposition Technique (PDT) has been used to derive positive and negative sequence components from three phase current and voltage signals. Three-phase instantaneous current signals and voltages are both sampled simultaneously in time series. Entire analysis presented in this paper is based on experimentally obtained motor current signatures. The obtained results provide a satisfactory level of accuracy in terms of segregating two different types of stator fault cases.","PeriodicalId":290479,"journal":{"name":"2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128607931","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

Dual zone industrial induction heater using MOSFET based high frequency hybrid resonant converter 基于MOSFET的高频混合谐振变换器的双区工业感应加热器

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737523

P. Sadhu, Ananyo Bhattacharya, N. Pal

{"title":"Dual zone industrial induction heater using MOSFET based high frequency hybrid resonant converter","authors":"P. Sadhu, Ananyo Bhattacharya, N. Pal","doi":"10.1109/CATCON.2013.6737523","DOIUrl":"https://doi.org/10.1109/CATCON.2013.6737523","url":null,"abstract":"In this paper a converter is described where both series and parallel resonant circuits are used. To minimize the losses, switching instant is chosen at zero current crossover instant. The converter scheme described in this paper consists of four MOSFETs in H-bridge configuration. It is used for industrial induction heating purposes comprising of dual zone heating. The switching frequency lies in the range of 30 kHz to 100 kHz. Maximum efficiency is achieved for operating frequency of 66.66 kHz. Earlier voltage controlled devices like IGBTs, MCTs were tested and found that the system was working perfectly. For above mentioned frequency, IGBT was the better option considering conduction losses. But the cost of power MOSFETs is lower than the same power rating IGBTs and MCTs. So, by considering the overall cost of the dual zone industrial induction heater, slightly greater conduction losses of MOSFETs can be accepted. For the system efficiency optimization, different control strategies are discussed. The two zones have different pipe diameters and output power levels. This paper presents a new approach of dual zone operation depending on the demand of hot fluid flow in the industrial application. It is saving the energy cost when it is operating in under load condition. The circuit is simulated with PSPICE and simulation results are specified at the end.","PeriodicalId":290479,"journal":{"name":"2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117000767","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

Prediction of transformer winding displacement from frequency response characteristics 从频率响应特性预测变压器绕组位移

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737517

M. Sathya, Ajith John Thomas, S. Usa

引用次数: 11

Partial discharge source classification by support vector machine 基于支持向量机的局部放电源分类

2013 IEEE 1st International Conference on Condition Assessment Techniques in Electrical Systems (CATCON) Pub Date : 2013-12-01 DOI: 10.1109/CATCON.2013.6737508

R. Sarathi, I. P. Merin Sheema, R. Abirami

引用次数: 13