Pub Date : 2010-11-09DOI: 10.1109/ICHQP.2010.5625486
Kun Zhao, P. Ciufo, S. Perera
This paper evaluates the changes in the ripple current for an electrolytic capacitor used in the dc-side of a single-phase rectifier circuit when subjected to input voltage fluctuations. The study has been undertaken in order to analyse the potential impact on capacitor lifetime. The key effect is that the capacitor ripple current, as a consequence of voltage fluctuations, increases dramatically and this phenomenon keeps deteriorating as the frequency of the voltage fluctuations increases. Simulations and experimental work confirm this phenomenon. Since the power loss and temperature rise are dependent on the capacitor equivalent series resistance (ESR) and ripple current components, an increase in ripple current under voltage fluctuation conditions is likely to accelerate this process, resulting in a reduced lifetime.
{"title":"Lifetime analysis of aluminum electrolytic capacitor subject to voltage fluctuations","authors":"Kun Zhao, P. Ciufo, S. Perera","doi":"10.1109/ICHQP.2010.5625486","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625486","url":null,"abstract":"This paper evaluates the changes in the ripple current for an electrolytic capacitor used in the dc-side of a single-phase rectifier circuit when subjected to input voltage fluctuations. The study has been undertaken in order to analyse the potential impact on capacitor lifetime. The key effect is that the capacitor ripple current, as a consequence of voltage fluctuations, increases dramatically and this phenomenon keeps deteriorating as the frequency of the voltage fluctuations increases. Simulations and experimental work confirm this phenomenon. Since the power loss and temperature rise are dependent on the capacitor equivalent series resistance (ESR) and ripple current components, an increase in ripple current under voltage fluctuation conditions is likely to accelerate this process, resulting in a reduced lifetime.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114851418","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625347
R. Singh, A. Singh
Solid state electronics is used to increase the energy efficiency of electrical load devices. The harmonic distortion of current is increasing with the enhanced use of nonlinear loads i.e. solid state devices. Examples of nonlinear loads are personal computer, laptop, laser printer, fax machine, television set (TV), fluorescent tube with electronic ballast, compact fluorescent lamp, battery charger, adjustable speed drives, uninterrupted power supply (UPS) and any other equipment powered by switched-mode power supply (SMPS) unit. These nonlinear loads draw more current than the fundamental current and cause overloading of the components of the distribution system. Transformers are major components of the distribution system and are mainly affected by this overloading. This leads to higher losses, reduces the strength of insulation and consequently leads to reduction of useful life of the transformer. Aging of transformer increases due to overheating caused by overloading. This paper presents the results of a case study of aging of transformer caused by harmonics due to non linear loads. Here two transformers of 500 kVA and 100 kVA are considered which supply a technical institution and residential campus respectively. The harmonic currents produced by these loads are captured in the laboratory and their effect on transformers is studied. An attempt has been made to calculate the energy loss due to harmonic distortion caused by these nonlinear loads. The rise in operating temperature due to harmonic current and hence life expectancy of the transformers are calculated.
{"title":"Aging of distribution transformers due to harmonics","authors":"R. Singh, A. Singh","doi":"10.1109/ICHQP.2010.5625347","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625347","url":null,"abstract":"Solid state electronics is used to increase the energy efficiency of electrical load devices. The harmonic distortion of current is increasing with the enhanced use of nonlinear loads i.e. solid state devices. Examples of nonlinear loads are personal computer, laptop, laser printer, fax machine, television set (TV), fluorescent tube with electronic ballast, compact fluorescent lamp, battery charger, adjustable speed drives, uninterrupted power supply (UPS) and any other equipment powered by switched-mode power supply (SMPS) unit. These nonlinear loads draw more current than the fundamental current and cause overloading of the components of the distribution system. Transformers are major components of the distribution system and are mainly affected by this overloading. This leads to higher losses, reduces the strength of insulation and consequently leads to reduction of useful life of the transformer. Aging of transformer increases due to overheating caused by overloading. This paper presents the results of a case study of aging of transformer caused by harmonics due to non linear loads. Here two transformers of 500 kVA and 100 kVA are considered which supply a technical institution and residential campus respectively. The harmonic currents produced by these loads are captured in the laboratory and their effect on transformers is studied. An attempt has been made to calculate the energy loss due to harmonic distortion caused by these nonlinear loads. The rise in operating temperature due to harmonic current and hence life expectancy of the transformers are calculated.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114720131","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625439
K. Jagieła, J. Rak, M. Gała, M. Kepinski
Electric AC arc furnaces used in steelmaking are nonlinear loads of large power. Due to chaotic nature of the electric arc and the melting process, such devices cause significant power quality problems in a supply network, mainly harmonics, inter-harmonics, unbalance, voltage dips and flickers. Limitation of this negative influence and optimization of the cast process is an important issue. In the paper there are presented results of identification of an AC arc furnace electric power parameters. We carried out digital measurements of voltages and currents in the furnace supply system during cast on the medium and low voltage sides of the furnace transformer. Next, we conducted frequency analysis and evaluation of the harmonics content in recorded waveforms at the secondary side of the furnace transformer. Computations were made using the fast Fourier transform (FFT) built-in in MATLAB. The waveforms of active power, current arc and THD indices during the melting process are presented. Furthermore, V-I characteristics of the AC electric arc, harmonics of voltages and currents as well as phasor diagrams for dominant harmonics at the melting and refining stages are shown. The conclusions and remarks concerning operation and development of a simulation model of an AC arc furnace are formulated.
{"title":"Identification of electric power parameters of AC arc furnace low voltage system","authors":"K. Jagieła, J. Rak, M. Gała, M. Kepinski","doi":"10.1109/ICHQP.2010.5625439","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625439","url":null,"abstract":"Electric AC arc furnaces used in steelmaking are nonlinear loads of large power. Due to chaotic nature of the electric arc and the melting process, such devices cause significant power quality problems in a supply network, mainly harmonics, inter-harmonics, unbalance, voltage dips and flickers. Limitation of this negative influence and optimization of the cast process is an important issue. In the paper there are presented results of identification of an AC arc furnace electric power parameters. We carried out digital measurements of voltages and currents in the furnace supply system during cast on the medium and low voltage sides of the furnace transformer. Next, we conducted frequency analysis and evaluation of the harmonics content in recorded waveforms at the secondary side of the furnace transformer. Computations were made using the fast Fourier transform (FFT) built-in in MATLAB. The waveforms of active power, current arc and THD indices during the melting process are presented. Furthermore, V-I characteristics of the AC electric arc, harmonics of voltages and currents as well as phasor diagrams for dominant harmonics at the melting and refining stages are shown. The conclusions and remarks concerning operation and development of a simulation model of an AC arc furnace are formulated.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123438847","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625385
A. B. Vasconcellos, T. I. R. C. Malheiro, R. Apolonio, L. de Annunciacao, R.S. Barros, T. V. da Silva
The main focus of this paper is to analyze the process of bucket elevator drive through line start and commands with frequency inverters. The modern commands use microprocessor systems that can reduce active power consumption and demand of real power. However there is concern about the harmonic distortion by response to those loads on the system. This paper presents laboratory measurements of a system of bucket elevator drive versus a conventional drive controlled by frequency inverter in search of solutions aimed at improving the efficiency and power quality in a drive system driving machine.
{"title":"Efficiency and power quality in a drive system driving machine","authors":"A. B. Vasconcellos, T. I. R. C. Malheiro, R. Apolonio, L. de Annunciacao, R.S. Barros, T. V. da Silva","doi":"10.1109/ICHQP.2010.5625385","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625385","url":null,"abstract":"The main focus of this paper is to analyze the process of bucket elevator drive through line start and commands with frequency inverters. The modern commands use microprocessor systems that can reduce active power consumption and demand of real power. However there is concern about the harmonic distortion by response to those loads on the system. This paper presents laboratory measurements of a system of bucket elevator drive versus a conventional drive controlled by frequency inverter in search of solutions aimed at improving the efficiency and power quality in a drive system driving machine.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124420053","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625432
J. Allahdadian, C. Bovo, V. Ilea, A. Berizzi
Nowadays, the penetration of wind power in power systems increases very fast. In particular, the Offshore Wind Farms (OWFs) are very promising for future development. The unpredictable real output of the Wind Farms (WF) can cause reactive power problems and lead to variable voltage profiles and consequently to voltage quality issues. Given these circumstances, this paper presents a summary of the main issues related to the Reactive Power Planning (RPP) stage of new OWFs and their connections. Thus, first the wind turbine generators types are described, emphasizing on their reactive output characteristics. Then, the major transmission technologies that can be used to connect the wind farms to the grid are reviewed. In the last part, a possible RPP models are given. With reference to the particular aspects related to the wind farms and the connection solutions.
{"title":"Reactive planning considering Offshore Wind Power generation","authors":"J. Allahdadian, C. Bovo, V. Ilea, A. Berizzi","doi":"10.1109/ICHQP.2010.5625432","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625432","url":null,"abstract":"Nowadays, the penetration of wind power in power systems increases very fast. In particular, the Offshore Wind Farms (OWFs) are very promising for future development. The unpredictable real output of the Wind Farms (WF) can cause reactive power problems and lead to variable voltage profiles and consequently to voltage quality issues. Given these circumstances, this paper presents a summary of the main issues related to the Reactive Power Planning (RPP) stage of new OWFs and their connections. Thus, first the wind turbine generators types are described, emphasizing on their reactive output characteristics. Then, the major transmission technologies that can be used to connect the wind farms to the grid are reviewed. In the last part, a possible RPP models are given. With reference to the particular aspects related to the wind farms and the connection solutions.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129846489","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625440
A. Amrane, N. Retière, D. Riu
The aim of this paper is to introduce a new approach for electrical power network modeling. It is based on fractal geometry. Over a wide range of frequency, power systems exhibit capacitive, inductive and resonant behaviors. In the resonant range, the authors show that it is possible to model the average behavior of the resonances by a power law. Its exponent is measured by a box counting method applied to a fractal analogous to the network. The resulting model is both accurate and of reduced order.
{"title":"New modeling of electrical power networks using fractal geometry","authors":"A. Amrane, N. Retière, D. Riu","doi":"10.1109/ICHQP.2010.5625440","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625440","url":null,"abstract":"The aim of this paper is to introduce a new approach for electrical power network modeling. It is based on fractal geometry. Over a wide range of frequency, power systems exhibit capacitive, inductive and resonant behaviors. In the resonant range, the authors show that it is possible to model the average behavior of the resonances by a power law. Its exponent is measured by a box counting method applied to a fractal analogous to the network. The resulting model is both accurate and of reduced order.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129536113","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625365
A. Dolara, M. Gualdoni, S. Leva
The High Speed/High Capacity railway lines uses the 2x25kV-50Hz power supply system that is supplied at high-voltage by dedicated lines that can be placed in close proximity to the railway line. The power system adopted for HS railway lines includes a lot of harmonic sources. Resonance phenomena can cause harmonics amplification with consequent problems as voltages distortion, interference problems and electromagnetic interference with communication lines. This paper presents a detailed model for the railway system (including the primary line) with the aim to evaluate the resonance frequency of the impedance seen by the pantograph.
{"title":"Effect of primary high voltage supply lines on the high speed AC railways systems","authors":"A. Dolara, M. Gualdoni, S. Leva","doi":"10.1109/ICHQP.2010.5625365","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625365","url":null,"abstract":"The High Speed/High Capacity railway lines uses the 2x25kV-50Hz power supply system that is supplied at high-voltage by dedicated lines that can be placed in close proximity to the railway line. The power system adopted for HS railway lines includes a lot of harmonic sources. Resonance phenomena can cause harmonics amplification with consequent problems as voltages distortion, interference problems and electromagnetic interference with communication lines. This paper presents a detailed model for the railway system (including the primary line) with the aim to evaluate the resonance frequency of the impedance seen by the pantograph.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129744340","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625346
A. Zobaa, A. Vaccaro, H. Zeineldin, A. Lecci, A. Abdel Monem
An optimization approach to determine the value of optimum LC compensator for time-variant nonsinusoidal environments is proposed. The optimization technique minimizes the transmission loss and/or maximizes the power factor. All the source voltage harmonics follow the same pattern. The equivalent source and load impedances are presented by complex time variations functions. The performance of the LC compensator is discussed by means of numerical examples taken from previous publications.
{"title":"Sizing of passive filters in time-varying nonsinusoidal environments","authors":"A. Zobaa, A. Vaccaro, H. Zeineldin, A. Lecci, A. Abdel Monem","doi":"10.1109/ICHQP.2010.5625346","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625346","url":null,"abstract":"An optimization approach to determine the value of optimum LC compensator for time-variant nonsinusoidal environments is proposed. The optimization technique minimizes the transmission loss and/or maximizes the power factor. All the source voltage harmonics follow the same pattern. The equivalent source and load impedances are presented by complex time variations functions. The performance of the LC compensator is discussed by means of numerical examples taken from previous publications.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130059953","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625490
A. Pavas, H. Torres-Sanchez, A. Delgadillo
This paper presents a method for calculation of stationary Power Quality Disturbances-PQD based on measurements, distribution system modeling and Monte Carlo techniques. A method to simulate PQD with specific random behavior based on Perfect Sampling is proposed. Three non-sinusoidal conditions power quantities are employed to illustrate the proposed methodology, and a proposal for statistical interpretation of simulated results is presented as well.
{"title":"A novel approach for the simulation of power quality stationary disturbances in electric power systems","authors":"A. Pavas, H. Torres-Sanchez, A. Delgadillo","doi":"10.1109/ICHQP.2010.5625490","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625490","url":null,"abstract":"This paper presents a method for calculation of stationary Power Quality Disturbances-PQD based on measurements, distribution system modeling and Monte Carlo techniques. A method to simulate PQD with specific random behavior based on Perfect Sampling is proposed. Three non-sinusoidal conditions power quantities are employed to illustrate the proposed methodology, and a proposal for statistical interpretation of simulated results is presented as well.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130140726","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 : 2010-11-09DOI: 10.1109/ICHQP.2010.5625376
I. Sadinezhad, V. Agelidis
This paper presents an optimization framework to estimate fundamental frequency and harmonics in power systems. The proposed technique includes a frequency tracking stage and a harmonic estimation layer. The architecture of the first layer which performs the frequency tracking task is based on the Newton and least-squares minimization techniques. The second layer extracts the frequency spectrum of the voltage/current waveform based on the descent search direction method which uses the estimated fundamental frequency by the previous stage. The simulation results in the MATLAB-Simulink prove faster estimation and more robust performance of the proposed technique in comparison with the three different methods which have been reviewed in this paper.
{"title":"A new optimization technique to measure frequency and harmonics in power systems","authors":"I. Sadinezhad, V. Agelidis","doi":"10.1109/ICHQP.2010.5625376","DOIUrl":"https://doi.org/10.1109/ICHQP.2010.5625376","url":null,"abstract":"This paper presents an optimization framework to estimate fundamental frequency and harmonics in power systems. The proposed technique includes a frequency tracking stage and a harmonic estimation layer. The architecture of the first layer which performs the frequency tracking task is based on the Newton and least-squares minimization techniques. The second layer extracts the frequency spectrum of the voltage/current waveform based on the descent search direction method which uses the estimated fundamental frequency by the previous stage. The simulation results in the MATLAB-Simulink prove faster estimation and more robust performance of the proposed technique in comparison with the three different methods which have been reviewed in this paper.","PeriodicalId":180078,"journal":{"name":"Proceedings of 14th International Conference on Harmonics and Quality of Power - ICHQP 2010","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129010209","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：