Pub Date : 2015-11-05DOI: 10.1109/AMPS.2015.7312746
Andrea Angioni, J. Shang, F. Ponci, A. Monti
The development of the smart grid requires new monitoring systems feasible to support automation functionalities as control of DER. As the key element in the monitoring system, the real time distribution system state estimation (DSSE) integrated with bad data processor is presented in this work. The developed DSSE is suitable for the real time application because it has the benefits of more computational efficiency, numerical stability and robustness against the measurements with large error. The DSSE is localized within a automation platform, from which the requirements from the output and the specifications of the input are derived. The performance of the real time DSSE is analyzed and discussed by means of simulations performed in a 16 bus distribution network.
{"title":"Design and test of a real time monitoring system based on a distribution system state estimation","authors":"Andrea Angioni, J. Shang, F. Ponci, A. Monti","doi":"10.1109/AMPS.2015.7312746","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312746","url":null,"abstract":"The development of the smart grid requires new monitoring systems feasible to support automation functionalities as control of DER. As the key element in the monitoring system, the real time distribution system state estimation (DSSE) integrated with bad data processor is presented in this work. The developed DSSE is suitable for the real time application because it has the benefits of more computational efficiency, numerical stability and robustness against the measurements with large error. The DSSE is localized within a automation platform, from which the requirements from the output and the specifications of the input are derived. The performance of the real time DSSE is analyzed and discussed by means of simulations performed in a 16 bus distribution network.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"423 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116690206","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312753
T. V. Rooyen, J. Rens, J. Desmet
Small signal stability is one focus of Wide Area Measurement Systems (WAMS). WAMS systems are becoming more widespread, driven by availability of synchrophasor data from Phasor Measurement Units (PMUs). In this paper, two methods capable of performing real-time small signal stability monitoring is evaluated by application to simulated data. Performance of the methods are tested to conditions likely to be found in practical use. The potential of both methods are further evaluated when applied to real-world data from a practical case study.
{"title":"Field performance of ambient modal estimation in small signal stability","authors":"T. V. Rooyen, J. Rens, J. Desmet","doi":"10.1109/AMPS.2015.7312753","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312753","url":null,"abstract":"Small signal stability is one focus of Wide Area Measurement Systems (WAMS). WAMS systems are becoming more widespread, driven by availability of synchrophasor data from Phasor Measurement Units (PMUs). In this paper, two methods capable of performing real-time small signal stability monitoring is evaluated by application to simulated data. Performance of the methods are tested to conditions likely to be found in practical use. The potential of both methods are further evaluated when applied to real-world data from a practical case study.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127233297","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312744
Pasquale Cuccaro, D. Gallo, C. Landi, M. Luiso, G. Romano
One of the enabling technologies for smart grid development are synchrophasor measurements typically performed by devices called phasor measurement unit (PMU), that produce synchronized subsecond high-resolution voltage and current measurements, so greatly augment the traditional response time of supervisory control and data acquisition measurements. In this paper we present an algorithm that measures amplitude, frequency and phase of voltage and current phasors with great accuracy. It is based on the recursive search of the solution of the maximum likelihood function and can track small variations of all phasor parameters. Preliminary results show that its performance is comparable to the Cramer-Rao Lower Bound.
{"title":"Recursive phasor estimation algorithm for synchrophasor measurement","authors":"Pasquale Cuccaro, D. Gallo, C. Landi, M. Luiso, G. Romano","doi":"10.1109/AMPS.2015.7312744","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312744","url":null,"abstract":"One of the enabling technologies for smart grid development are synchrophasor measurements typically performed by devices called phasor measurement unit (PMU), that produce synchronized subsecond high-resolution voltage and current measurements, so greatly augment the traditional response time of supervisory control and data acquisition measurements. In this paper we present an algorithm that measures amplitude, frequency and phase of voltage and current phasors with great accuracy. It is based on the recursive search of the solution of the maximum likelihood function and can track small variations of all phasor parameters. Preliminary results show that its performance is comparable to the Cramer-Rao Lower Bound.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122963525","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312738
D. Serfontein, J. Rens, Gerhard Botha, J. Desmet
The quantification of harmonic emission requires an accurate representation of the network harmonic impedances. A number of techniques have been proposed to make the assessment of the network harmonic impedances practical and less invasive. Using actual event data, captured at a solar farm, this paper aims to utilize existing assessment techniques to develop an online network harmonic impedances assessment model. The harmonic impedances can then be updated per event and automatically be corrected as the network develops. This technique is noninvasive and will provide an accurate estimation of the network impedances enabling the continuous assessment of power quality emissions.
{"title":"Continuous harmonic impedance assessment using online measurements","authors":"D. Serfontein, J. Rens, Gerhard Botha, J. Desmet","doi":"10.1109/AMPS.2015.7312738","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312738","url":null,"abstract":"The quantification of harmonic emission requires an accurate representation of the network harmonic impedances. A number of techniques have been proposed to make the assessment of the network harmonic impedances practical and less invasive. Using actual event data, captured at a solar farm, this paper aims to utilize existing assessment techniques to develop an online network harmonic impedances assessment model. The harmonic impedances can then be updated per event and automatically be corrected as the network develops. This technique is noninvasive and will provide an accurate estimation of the network impedances enabling the continuous assessment of power quality emissions.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116292653","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312733
Cassio Binkowski, C. Crovato
In this paper we introduce a numeric method to resolve a non-contact voltage sensor equation and track the original voltage in the measured surface for medium and high alternated voltage systems. We introduce the non-contact sensor itself, its principle of operation and equations, and also the method we use to increase the sensitivity of the measurement. The numeric method is then presented in detail, as well as the simulation results and an assessment of accuracy. We were able to achieve very good results with the presented technique, with the best results falling under 1% of estimation error for the fundamental frequency, as well as for the 3rd, 5th and 7th harmonics.
{"title":"Increasing sensitivity on non-contact voltage sensor using time-varying components: A numerical analysis for accuracy assessment","authors":"Cassio Binkowski, C. Crovato","doi":"10.1109/AMPS.2015.7312733","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312733","url":null,"abstract":"In this paper we introduce a numeric method to resolve a non-contact voltage sensor equation and track the original voltage in the measured surface for medium and high alternated voltage systems. We introduce the non-contact sensor itself, its principle of operation and equations, and also the method we use to increase the sensitivity of the measurement. The numeric method is then presented in detail, as well as the simulation results and an assessment of accuracy. We were able to achieve very good results with the presented technique, with the best results falling under 1% of estimation error for the fundamental frequency, as well as for the 3rd, 5th and 7th harmonics.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124483651","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312734
W. Dickerson
Phasor measurement unit (PMU) performance depends on the performance of the PMU's analog input section and the limitations of its DSP algorithms. For the different PMU performance requirements established in the standards, the relative importance of these two factors varies significantly. For steady-state frequency and rate-of-change-of-frequency (ROCOF) measurements, this paper shows that estimation error is primarily dependent on noise mechanisms in the input section and the effective bandwidth of the signal processing algorithms. Estimation error may be predicted based on understanding these two factors, and optimum performance may be realized by careful design choices. When the PMU function is implemented with separate data acquisition and computation functions, this interaction must be carefully considered, so that the PMU results are equivalent to those from an integrated, conformant PMU - as users expect.
{"title":"Effect of PMU analog input section performance on frequency and ROCOF estimation error","authors":"W. Dickerson","doi":"10.1109/AMPS.2015.7312734","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312734","url":null,"abstract":"Phasor measurement unit (PMU) performance depends on the performance of the PMU's analog input section and the limitations of its DSP algorithms. For the different PMU performance requirements established in the standards, the relative importance of these two factors varies significantly. For steady-state frequency and rate-of-change-of-frequency (ROCOF) measurements, this paper shows that estimation error is primarily dependent on noise mechanisms in the input section and the effective bandwidth of the signal processing algorithms. Estimation error may be predicted based on understanding these two factors, and optimum performance may be realized by careful design choices. When the PMU function is implemented with separate data acquisition and computation functions, this interaction must be carefully considered, so that the PMU results are equivalent to those from an integrated, conformant PMU - as users expect.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128279423","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312747
P. Ferrari, A. Flammini, Matteo Loda, S. Rinaldi, Diego Pagnoncelli, E. Ragaini
Smart Grids require a pervasive communication network to interconnect their intelligent devices (e.g. generators, protections, and meters) that are usually distributed over a wide area. Recently, the Long Term Evolution (LTE) wireless cellular network communication technology has been introduced and its diffusion is rapidly increasing. As a consequence, LTE may be considered as a viable opportunity for the communication in Smart Grid, too. The aim of the paper is to experimentally verify the LTE performance of a current public LTE network when it is used as backbone for a Smart Grid system. The results of the experimental characterization highlight that the LTE may be taken into consideration for the design of a communication infrastructure limited to secondary/assisting tasks related to Smart Grid automation; the Round Trip Time (RTT) is typically below 100 ms, fully compatible with the least demanding smart grid automation.
{"title":"First experimental characterization of LTE for automation of Smart Grid","authors":"P. Ferrari, A. Flammini, Matteo Loda, S. Rinaldi, Diego Pagnoncelli, E. Ragaini","doi":"10.1109/AMPS.2015.7312747","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312747","url":null,"abstract":"Smart Grids require a pervasive communication network to interconnect their intelligent devices (e.g. generators, protections, and meters) that are usually distributed over a wide area. Recently, the Long Term Evolution (LTE) wireless cellular network communication technology has been introduced and its diffusion is rapidly increasing. As a consequence, LTE may be considered as a viable opportunity for the communication in Smart Grid, too. The aim of the paper is to experimentally verify the LTE performance of a current public LTE network when it is used as backbone for a Smart Grid system. The results of the experimental characterization highlight that the LTE may be taken into consideration for the design of a communication infrastructure limited to secondary/assisting tasks related to Smart Grid automation; the Round Trip Time (RTT) is typically below 100 ms, fully compatible with the least demanding smart grid automation.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121166464","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312748
P. Jamborsalamati, A. Sadu, F. Ponci, A. Monti
This paper presents a novel Distributed FLISR algorithm that uses Intelligent Electronic Devices (IEDs) configured to communicate the status changes and the measurements with one another using IEC 61850 GOOSE messages. Evaluation of the performance of the algorithm requires real-time simulation; therefore, a modular real time test platform using Real Time Digital Simulator (RTDS) and IEDs supporting IEC 61850 GOOSE is setup. A list of userdefined information including status changes and measurements that needs to be exchanged by the IEDs, required for implementing the proposed algorithm is presented. To validate the performance and showcase the flexibilities offered by the algorithm, like measurement-based selectivity in Service Restoration and covering of multiple faults, three case scenarios are simulated with a model of the real distribution grid, managed by A2A Reti Elettriche SpA in Brescia.
本文提出了一种新的分布式FLISR算法，该算法使用智能电子设备(ied)配置，使用IEC 61850 GOOSE消息相互通信状态变化和测量。对算法性能的评估需要进行实时仿真;因此，建立了一个使用实时数字模拟器(RTDS)和支持IEC 61850 GOOSE的ied的模块化实时测试平台。给出了实现所提议的算法所需的用户定义信息列表，其中包括需要由ied交换的状态变化和度量。为了验证该算法的性能并展示其灵活性，如基于测量的服务恢复选择性和多故障覆盖，用布雷西亚A2A Reti electriche SpA公司管理的实际配电网模型模拟了三种情况。
{"title":"Design, implementation and real-time testing of an IEC 61850 based FLISR algorithm for smart distribution grids","authors":"P. Jamborsalamati, A. Sadu, F. Ponci, A. Monti","doi":"10.1109/AMPS.2015.7312748","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312748","url":null,"abstract":"This paper presents a novel Distributed FLISR algorithm that uses Intelligent Electronic Devices (IEDs) configured to communicate the status changes and the measurements with one another using IEC 61850 GOOSE messages. Evaluation of the performance of the algorithm requires real-time simulation; therefore, a modular real time test platform using Real Time Digital Simulator (RTDS) and IEDs supporting IEC 61850 GOOSE is setup. A list of userdefined information including status changes and measurements that needs to be exchanged by the IEDs, required for implementing the proposed algorithm is presented. To validate the performance and showcase the flexibilities offered by the algorithm, like measurement-based selectivity in Service Restoration and covering of multiple faults, three case scenarios are simulated with a model of the real distribution grid, managed by A2A Reti Elettriche SpA in Brescia.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117305433","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312740
R. Ferrero, S. Toscani, G. Dotelli, P. G. Stampino, S. Latorrata
PEM fuel cell (FC) operation is likely to be characterized by voltage dips on time scales shorter than 1 s, arising from temporary flooding of gas channels or porous layers, particularly when the FC is operated at high humidity levels. If supercapacitors are employed together with the FC as energy storage systems, they can make up for the temporary lack of energy produced by the FC. However, the steep slopes of the voltage dips affect the energy that can be actually delivered by the supercapacitor because of the frequency dependence of its capacitance, and this should be taken into account in sizing the supercapacitor. In this paper, the supercapacitor response to a FC voltage dip is simulated and discussed, based on an experimentally identified supercapacitor model and a typical voltage dip measured on a single PEM FC.
{"title":"Response of a hybrid supercapacitor - PEM fuel cell system to fast fuel cell energy dips","authors":"R. Ferrero, S. Toscani, G. Dotelli, P. G. Stampino, S. Latorrata","doi":"10.1109/AMPS.2015.7312740","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312740","url":null,"abstract":"PEM fuel cell (FC) operation is likely to be characterized by voltage dips on time scales shorter than 1 s, arising from temporary flooding of gas channels or porous layers, particularly when the FC is operated at high humidity levels. If supercapacitors are employed together with the FC as energy storage systems, they can make up for the temporary lack of energy produced by the FC. However, the steep slopes of the voltage dips affect the energy that can be actually delivered by the supercapacitor because of the frequency dependence of its capacitance, and this should be taken into account in sizing the supercapacitor. In this paper, the supercapacitor response to a FC voltage dip is simulated and discussed, based on an experimentally identified supercapacitor model and a typical voltage dip measured on a single PEM FC.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114865180","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 : 2015-11-05DOI: 10.1109/AMPS.2015.7312742
A. Emleh, A. D. Beer, H. Ferreira, A. Vinck
The mercury vapor lamp is the oldest high intensity discharge technology lamp that uses an electric arc, and comes in different shapes and designs. It creates a very bright light by using an arc through vaporized mercury in a high pressure tube. This lamp can cause unwanted interference to the smart-grid network or power line communications channel when connected to the channel's wiring system. In this paper we investigate the negative effects that the mercury vapor lamps with electric ballast have on the smart-grid PLC channel. This can have a strong and negative effect when using the smart-grid PLC network to control the automatic switching of lamps in public places. The narrowband and broadband channels are investigated where the interference level from mercury vapor lamps is significantly below the allowed maximum PLC signal levels on the band: (3 kHz - 150 kHz), and competes with Electromagnetic Compatibility (EMC) levels on the 150 kHz - 30 MHz band. The mercury vapor lamp uses an electric ballast to connect to the powerline system. This connection is explained in detail.
{"title":"On mercury vapor lamps and their effect on the smart-grid PLC channel","authors":"A. Emleh, A. D. Beer, H. Ferreira, A. Vinck","doi":"10.1109/AMPS.2015.7312742","DOIUrl":"https://doi.org/10.1109/AMPS.2015.7312742","url":null,"abstract":"The mercury vapor lamp is the oldest high intensity discharge technology lamp that uses an electric arc, and comes in different shapes and designs. It creates a very bright light by using an arc through vaporized mercury in a high pressure tube. This lamp can cause unwanted interference to the smart-grid network or power line communications channel when connected to the channel's wiring system. In this paper we investigate the negative effects that the mercury vapor lamps with electric ballast have on the smart-grid PLC channel. This can have a strong and negative effect when using the smart-grid PLC network to control the automatic switching of lamps in public places. The narrowband and broadband channels are investigated where the interference level from mercury vapor lamps is significantly below the allowed maximum PLC signal levels on the band: (3 kHz - 150 kHz), and competes with Electromagnetic Compatibility (EMC) levels on the 150 kHz - 30 MHz band. The mercury vapor lamp uses an electric ballast to connect to the powerline system. This connection is explained in detail.","PeriodicalId":374309,"journal":{"name":"2015 IEEE International Workshop on Applied Measurements for Power Systems (AMPS)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123550713","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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