Pub Date : 2004-11-08DOI: 10.1109/TDC.2004.1432466
M. Saied
This paper presents a new model for the accurate calculation of the abnormal waveform of the breaker reignition current following the interruption of the capacitive charging current of a long unloaded overhead line section. The breaker is assumed located a some distance from the source. The suggested model is based on the circuit analysis of the cascaded cables and transmission line sections in terms of the ABCD constants using their distributed parameters, e.g. series inductance and shunt capacitance. The new model is verified using the results available in the literature obtained by applying the approximate, much more tedious and time consuming traveling wave approach. The model is applied to investigate the effect of the different parameters (such as the lengths and the surge impedances of the cable and overhead line) on the magnitudes and waveforms of the breaker reignition current.
{"title":"A model for computing the breaker reignition current following interruption of the charging current of long unloaded line","authors":"M. Saied","doi":"10.1109/TDC.2004.1432466","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432466","url":null,"abstract":"This paper presents a new model for the accurate calculation of the abnormal waveform of the breaker reignition current following the interruption of the capacitive charging current of a long unloaded overhead line section. The breaker is assumed located a some distance from the source. The suggested model is based on the circuit analysis of the cascaded cables and transmission line sections in terms of the ABCD constants using their distributed parameters, e.g. series inductance and shunt capacitance. The new model is verified using the results available in the literature obtained by applying the approximate, much more tedious and time consuming traveling wave approach. The model is applied to investigate the effect of the different parameters (such as the lengths and the surge impedances of the cable and overhead line) on the magnitudes and waveforms of the breaker reignition current.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121416816","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432421
Moises Vidal Ribeiro, S. Mitra, J. Romano
This paper addresses the compression of power quality disturbance events when the monitored signals are composed of several harmonics and transients. We propose the use of a new approach for amplitude, frequency, and phase estimations of multiple sinusoids along with a transform coding technique based on discrete wavelet transform for the compression of monitored signals. The new method can be considered as a modified version of the recently proposed enhanced data compression method (EDCM). Numerical results show that the new method not only provide almost the same performance as that of the EDCM when only the fundamental and transient signals are in the monitored signals, but also overcomes the limitation of the EDCM when applied for compression of the monitored signals composed of many harmonic and transient components.
{"title":"Digital signal processing techniques for compression of power quality disturbance events: new results","authors":"Moises Vidal Ribeiro, S. Mitra, J. Romano","doi":"10.1109/TDC.2004.1432421","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432421","url":null,"abstract":"This paper addresses the compression of power quality disturbance events when the monitored signals are composed of several harmonics and transients. We propose the use of a new approach for amplitude, frequency, and phase estimations of multiple sinusoids along with a transform coding technique based on discrete wavelet transform for the compression of monitored signals. The new method can be considered as a modified version of the recently proposed enhanced data compression method (EDCM). Numerical results show that the new method not only provide almost the same performance as that of the EDCM when only the fundamental and transient signals are in the monitored signals, but also overcomes the limitation of the EDCM when applied for compression of the monitored signals composed of many harmonic and transient components.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126431702","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432406
L. de V. B. Machado Neto, C. Cabral, D. O. Filho, A. Diniz
The sustainability of standalone photovoltaic systems passes through an accompaniment of the systems installed in the field. To subsidize this accompaniment procedures had been developed for monitoring a similar system in a laboratory. The standalone photovoltaic system implanted in the Research Center in Intelligent Energy of the Group of Studies in Energy-CPEI GREEN PUC Minas is similar to the systems installed by Companhia Energetica de Minas Gerais-CEMIG in the schools of isolated communities, inside the solar light program. A simulation of the system was implemented and the aims were to optimize the project and carry out a comparative study with the monitoring results. The procedure for assembly of the monitoring facility consisted of the implantation of the voltage and current sensors, implantation of the irradiance and temperature sensors, installation of the acquisition boards and development of the monitoring program. The results presented here will allow the development of a program of preventive maintenance of the photovoltaic systems installed by CEMIG.
独立光伏系统的可持续性通过在现场安装的系统的伴奏。为了补贴这种陪伴程序，已经制定了在实验室监测类似系统的程序。安装在米纳斯吉拉斯州能源研究小组(cpei GREEN PUC Minas)智能能源研究中心的独立光伏系统与米纳斯吉拉斯州cemig能源公司在隔离社区学校安装的太阳能照明系统类似。对该系统进行了仿真，目的是优化方案，并与监测结果进行比较研究。监测设备的组装过程包括电压和电流传感器的植入，辐照度和温度传感器的植入，采集板的安装和监测程序的开发。这里提出的结果将允许制定由CEMIG安装的光伏系统的预防性维护计划。
{"title":"Monitoring of photovoltaic systems for performance evaluation and fault identification","authors":"L. de V. B. Machado Neto, C. Cabral, D. O. Filho, A. Diniz","doi":"10.1109/TDC.2004.1432406","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432406","url":null,"abstract":"The sustainability of standalone photovoltaic systems passes through an accompaniment of the systems installed in the field. To subsidize this accompaniment procedures had been developed for monitoring a similar system in a laboratory. The standalone photovoltaic system implanted in the Research Center in Intelligent Energy of the Group of Studies in Energy-CPEI GREEN PUC Minas is similar to the systems installed by Companhia Energetica de Minas Gerais-CEMIG in the schools of isolated communities, inside the solar light program. A simulation of the system was implemented and the aims were to optimize the project and carry out a comparative study with the monitoring results. The procedure for assembly of the monitoring facility consisted of the implantation of the voltage and current sensors, implantation of the irradiance and temperature sensors, installation of the acquisition boards and development of the monitoring program. The results presented here will allow the development of a program of preventive maintenance of the photovoltaic systems installed by CEMIG.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115239494","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432412
F. Kober, F. Lemos
This paper presents the use of the openGL technology in the construction of three-dimensional graphs for the exhibition of the results of power flow algorithms in CAD tools for simulation and analysis of geo-located electric energy distribution networks, in order to present to the user a clear way to evaluate the general voltage behavior along the network.
{"title":"On use of openGL technology for 3D visualizations in power systems CAD tools","authors":"F. Kober, F. Lemos","doi":"10.1109/TDC.2004.1432412","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432412","url":null,"abstract":"This paper presents the use of the openGL technology in the construction of three-dimensional graphs for the exhibition of the results of power flow algorithms in CAD tools for simulation and analysis of geo-located electric energy distribution networks, in order to present to the user a clear way to evaluate the general voltage behavior along the network.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115714030","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432342
J. Taboada, J.C. Cabrera, G. Ramos, M.T. Torres
This paper presents a model for the generation of patterns of phenomena associated to power quality in electric networks. This model is based on wavelet theory and on the use of wavelet tools available in MATLAB version 6.0. The method was developed by means of the DWT (discrete wavelet transform) analysis. The DWT decomposes the entry signal and any difference with the pure sine signal of 60 Hz with the corresponding amplitude is detected. Then the signal's power curve is analyzed and the deviation with the corresponding power curve of the fundamental signal is obtained. This deviation determines a pattern for each of the phenomena and it becomes easily recognizable and identifiable. Finally the foundation to train a neural network with these patterns is laid so the network can identify the phenomena, its risks and possible solutions.
{"title":"Generation of patterns of phenomena associated to power quality using the wavelet transform","authors":"J. Taboada, J.C. Cabrera, G. Ramos, M.T. Torres","doi":"10.1109/TDC.2004.1432342","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432342","url":null,"abstract":"This paper presents a model for the generation of patterns of phenomena associated to power quality in electric networks. This model is based on wavelet theory and on the use of wavelet tools available in MATLAB version 6.0. The method was developed by means of the DWT (discrete wavelet transform) analysis. The DWT decomposes the entry signal and any difference with the pure sine signal of 60 Hz with the corresponding amplitude is detected. Then the signal's power curve is analyzed and the deviation with the corresponding power curve of the fundamental signal is obtained. This deviation determines a pattern for each of the phenomena and it becomes easily recognizable and identifiable. Finally the foundation to train a neural network with these patterns is laid so the network can identify the phenomena, its risks and possible solutions.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"255 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124197483","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432417
A. Santos, D. Slomovitz
An error compensation technique for measuring current transformers is described. An example is shown for current transformers installed in 150 kV switching devices. Initial ratio errors in the order of 4% and phase shifts around 20 min were reduced to 0.1% and 6 min after the compensation.
{"title":"Error compensation of current transformers in high voltage networks","authors":"A. Santos, D. Slomovitz","doi":"10.1109/TDC.2004.1432417","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432417","url":null,"abstract":"An error compensation technique for measuring current transformers is described. An example is shown for current transformers installed in 150 kV switching devices. Initial ratio errors in the order of 4% and phase shifts around 20 min were reduced to 0.1% and 6 min after the compensation.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116868588","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432424
C. Nascimento, J. Brito, E.R.B. Filho, G. Braga, G. Miranda, A. Bracarense, S. Ueda
This work covers the main research, results and conclusions achieved by CEMIG over the past 15 years on ampacity of overhead transmission lines. The main focus of the research was to assist designers in searching answers regarding the technical knowledge related to the major questions involving ampacity, such as: validation of the method for calculation of ampacity, application of real-time line monitoring technology, studies on aging of CAA cables in addition to other ampacity correlated topics. Currently, Cemig continues to invest on improvement of the technical knowledge about ampacity in a comprehensive form by means of regionalized measurement of wind speed and ambient temperature, real-time monitoring of lines, setting up of a weather network, computational simulations validated with experiment field data, development of new cable alloys and geometry and, later, the development of studies of the atmospheric wind boundary layer.
{"title":"The state of the art for increased overhead line ampacity utilizing new technologies and statistical criteria","authors":"C. Nascimento, J. Brito, E.R.B. Filho, G. Braga, G. Miranda, A. Bracarense, S. Ueda","doi":"10.1109/TDC.2004.1432424","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432424","url":null,"abstract":"This work covers the main research, results and conclusions achieved by CEMIG over the past 15 years on ampacity of overhead transmission lines. The main focus of the research was to assist designers in searching answers regarding the technical knowledge related to the major questions involving ampacity, such as: validation of the method for calculation of ampacity, application of real-time line monitoring technology, studies on aging of CAA cables in addition to other ampacity correlated topics. Currently, Cemig continues to invest on improvement of the technical knowledge about ampacity in a comprehensive form by means of regionalized measurement of wind speed and ambient temperature, real-time monitoring of lines, setting up of a weather network, computational simulations validated with experiment field data, development of new cable alloys and geometry and, later, the development of studies of the atmospheric wind boundary layer.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117213168","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432508
J. Bermúdez, M. Ricucci, S. Gómez
As a consequence of the shortage of water in the hydroelectric reservoirs, the Venezuelan interconnected system decided to drop the operational frequency in order to save water. After analyzing the characteristics of the different types of loads of an electrical system, coefficients of sensitivity were adopted according to the Venezuelan reality for active and reactive loads versus voltage magnitude and frequency. This paper summarizes improvements on the studies of the impact of working at low frequencies by running a power flow over the Venezuelan interconnected system, showing a crossed and unavoidable effect of the frequency and voltage on the demanded and generated power. According to the results of the power flow, it is not advisable in the first instance to work at low frequency. In this conclusion stand out three fundamental factors, first of all the minor reduction in the demand, the damping effect of the transmission network and the existence of a not neglectable percentage of load that behaves as constant energy types, besides the classical limitation associated to the operation at under rated frequency.
{"title":"Impact of the variation of the operational frequency and voltage on the Venezuelan interconnected system","authors":"J. Bermúdez, M. Ricucci, S. Gómez","doi":"10.1109/TDC.2004.1432508","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432508","url":null,"abstract":"As a consequence of the shortage of water in the hydroelectric reservoirs, the Venezuelan interconnected system decided to drop the operational frequency in order to save water. After analyzing the characteristics of the different types of loads of an electrical system, coefficients of sensitivity were adopted according to the Venezuelan reality for active and reactive loads versus voltage magnitude and frequency. This paper summarizes improvements on the studies of the impact of working at low frequencies by running a power flow over the Venezuelan interconnected system, showing a crossed and unavoidable effect of the frequency and voltage on the demanded and generated power. According to the results of the power flow, it is not advisable in the first instance to work at low frequency. In this conclusion stand out three fundamental factors, first of all the minor reduction in the demand, the damping effect of the transmission network and the existence of a not neglectable percentage of load that behaves as constant energy types, besides the classical limitation associated to the operation at under rated frequency.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116284881","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432505
O.M.O. Gatous, J. Filho
This paper presents a new and quite simple formulation to calculate the skin-effect resistance and internal inductance of a solid cylindrical conductor. The formulation is obtained from the exact solution of the Maxwell's wave equation of an electrical field in the direction of propagation. The Fourier transform method is used to obtain the frequency-domain solution. The results are presented in graphical form showing the conductor resistance and internal inductance as a function of frequency.
{"title":"A new formulation for skin-effect resistance and internal inductance frequency-dependent of a solid cylindrical conductor","authors":"O.M.O. Gatous, J. Filho","doi":"10.1109/TDC.2004.1432505","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432505","url":null,"abstract":"This paper presents a new and quite simple formulation to calculate the skin-effect resistance and internal inductance of a solid cylindrical conductor. The formulation is obtained from the exact solution of the Maxwell's wave equation of an electrical field in the direction of propagation. The Fourier transform method is used to obtain the frequency-domain solution. The results are presented in graphical form showing the conductor resistance and internal inductance as a function of frequency.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122176090","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 : 2004-11-08DOI: 10.1109/TDC.2004.1432490
K. Hashimoto, N. Kagan
This paper aims at contributing for the estimation of electrical performance in the distribution of electric energy. Electrical performance is assumed to be the evaluation of network congestion parameters, losses and voltage level. The electrical performance estimation is formulated according to an optimization problem where the objective functions correspond to an evaluation of occurrence probability, and also correspond to a proximity evaluation of calculated parameters with values obtained by measurement. Load values are discretized according to occurrence probabilities within each interval, so that formulation results in a multiobjective combinatorial optimization of exponential dimension. Network reduction procedures to substantially reduce decision domain and network expansion procedures to rebuild it are proposed. Specific heuristics are also proposed to get solutions with load diversity and unbalanced. In order to adequately apply these heuristics, a metaheuristic evolutionary method to build feasible solutions is proposed and applied, and ranked according to Pareto's concept. The mathematical formulation of optimization is flexible enough to be effectively applied taking into account different levels of supervisory systems developed in the utilities. The metaheuristic evolutionary model proposed was applied to a representative case with main potentialities and weak points to be improved.
{"title":"Multiobjective combinatorial optimization techniques applied to electrical performance estimation of distribution networks","authors":"K. Hashimoto, N. Kagan","doi":"10.1109/TDC.2004.1432490","DOIUrl":"https://doi.org/10.1109/TDC.2004.1432490","url":null,"abstract":"This paper aims at contributing for the estimation of electrical performance in the distribution of electric energy. Electrical performance is assumed to be the evaluation of network congestion parameters, losses and voltage level. The electrical performance estimation is formulated according to an optimization problem where the objective functions correspond to an evaluation of occurrence probability, and also correspond to a proximity evaluation of calculated parameters with values obtained by measurement. Load values are discretized according to occurrence probabilities within each interval, so that formulation results in a multiobjective combinatorial optimization of exponential dimension. Network reduction procedures to substantially reduce decision domain and network expansion procedures to rebuild it are proposed. Specific heuristics are also proposed to get solutions with load diversity and unbalanced. In order to adequately apply these heuristics, a metaheuristic evolutionary method to build feasible solutions is proposed and applied, and ranked according to Pareto's concept. The mathematical formulation of optimization is flexible enough to be effectively applied taking into account different levels of supervisory systems developed in the utilities. The metaheuristic evolutionary model proposed was applied to a representative case with main potentialities and weak points to be improved.","PeriodicalId":126347,"journal":{"name":"2004 IEEE/PES Transmision and Distribution Conference and Exposition: Latin America (IEEE Cat. No. 04EX956)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124807808","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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