Pub Date : 2012-10-01DOI: 10.1109/POWERCON.2012.6401289
V. Kurbatsky, N. Tomin
Conventional monitoring systems do not address the increasing complexity of electric power systems (EPSs). Bringing together the strengths of artificial intelligence technologies, special software and Wide Area Monitoring System/Phasor measurement unit (WAMS/(PMU) technologies it provides a holistic, intelligent approach to the monitoring of complex EPSs for the detection of emerging patterns. This approach to intelligent monitoring provides advantages when looking for trends or patterns or emergent behavior from data collected from different sensors on complex processes. In this paper the authors presents the smart system of monitoring and forecasting for EPSs with using these technologies. The experimental studies have demonstrated the performance of the proposed intelligent methods and approaches of this smart system.
{"title":"Smart system of monitoring and forecasting for electric power systems","authors":"V. Kurbatsky, N. Tomin","doi":"10.1109/POWERCON.2012.6401289","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401289","url":null,"abstract":"Conventional monitoring systems do not address the increasing complexity of electric power systems (EPSs). Bringing together the strengths of artificial intelligence technologies, special software and Wide Area Monitoring System/Phasor measurement unit (WAMS/(PMU) technologies it provides a holistic, intelligent approach to the monitoring of complex EPSs for the detection of emerging patterns. This approach to intelligent monitoring provides advantages when looking for trends or patterns or emergent behavior from data collected from different sensors on complex processes. In this paper the authors presents the smart system of monitoring and forecasting for EPSs with using these technologies. The experimental studies have demonstrated the performance of the proposed intelligent methods and approaches of this smart system.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114890518","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401301
L. Ying, Shen Chen, Liu Feng
Recently, several power grids of China came across low frequency oscillations which are difficult to explain by the traditional negative damping mechanism. Some researchers suggest that those oscillations be caused by external periodic disturbances according to the forced oscillation mechanism. It takes no doubt that the oscillation source location (means locating the disturbances) is imperative and decisive to eliminate such a kind of oscillations. This paper proposes a location methodology based on Energy Supply on Port derived from the Port-Controlled Hamiltonian theory. By calculating the energy injected to the network at corresponding ports, the oscillation sources can be effectively located, even in complicated systems containing various kinds of control devices such as governors and exciters. Different from the traditional methodology based on eigen-analysis, the proposed methodology is naturally decentralized without the dependency on global measurements. Case studies on the standard 4-machine 2-area system and the IEEE-118 bus system show the effectiveness and efficiency of the proposed methodology.
{"title":"An energy-based methodology for locating the source of forced oscillations in power systems","authors":"L. Ying, Shen Chen, Liu Feng","doi":"10.1109/POWERCON.2012.6401301","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401301","url":null,"abstract":"Recently, several power grids of China came across low frequency oscillations which are difficult to explain by the traditional negative damping mechanism. Some researchers suggest that those oscillations be caused by external periodic disturbances according to the forced oscillation mechanism. It takes no doubt that the oscillation source location (means locating the disturbances) is imperative and decisive to eliminate such a kind of oscillations. This paper proposes a location methodology based on Energy Supply on Port derived from the Port-Controlled Hamiltonian theory. By calculating the energy injected to the network at corresponding ports, the oscillation sources can be effectively located, even in complicated systems containing various kinds of control devices such as governors and exciters. Different from the traditional methodology based on eigen-analysis, the proposed methodology is naturally decentralized without the dependency on global measurements. Case studies on the standard 4-machine 2-area system and the IEEE-118 bus system show the effectiveness and efficiency of the proposed methodology.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114912013","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401314
Minxiao Han, Hailong Wang, Xiaojiang Guo
This paper focuses on the study of the paralleled multi-terminal HVDC system (MTDC). A control strategy is investigated for LCC-MTDC system based on the autonomous decentralized theory. By this approach, a stable operating point can be reached from initial starting independent of communication coordination. Simulation is performed on a model of LCC-MTDC system with four terminals using PSCAD/EMTDC and the results show that the proposed control strategy has satisfactory dynamic characteristics and the LCC-MTDC system can recover and reach a stable operating state after a temporary fault even without communication. This control strategy may contribute to extension of MTDC system, even the development of DC grid.
{"title":"Control strategy research of LCC based multiterminal HVDC system","authors":"Minxiao Han, Hailong Wang, Xiaojiang Guo","doi":"10.1109/POWERCON.2012.6401314","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401314","url":null,"abstract":"This paper focuses on the study of the paralleled multi-terminal HVDC system (MTDC). A control strategy is investigated for LCC-MTDC system based on the autonomous decentralized theory. By this approach, a stable operating point can be reached from initial starting independent of communication coordination. Simulation is performed on a model of LCC-MTDC system with four terminals using PSCAD/EMTDC and the results show that the proposed control strategy has satisfactory dynamic characteristics and the LCC-MTDC system can recover and reach a stable operating state after a temporary fault even without communication. This control strategy may contribute to extension of MTDC system, even the development of DC grid.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124201400","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401468
R. Mehta, B. Oza, N. Nair, M. Kumar
This paper presents the laboratory simulation emulating application of a numerical distance relay. It yields a realistic scaled model for a two section radial feeder. Lumped models of transmission lines are constructed, which resemble the actual system. Protection of such realistic feeder enables the students and engineers to get a feel as to how a distance protection works. Provision is also made to change the relay connections from its actual location in the system to the test bench location which helps in testing a relay. The setup as a whole is useful for getting the actual exposure of the complex procedure of co-ordination of relay settings. Advanced technical facilities available in the modern numerical relays are exploited for demonstration purpose in the laboratory environment by hardware simulation. The development was done through senior design projects, thus imparting design exposure to students while reducing the development cost. The work has been done to enhance laboratory curriculum and provide hands-on training to students in laboratory environment.
{"title":"Simulation of numerical distance protection through senior design project","authors":"R. Mehta, B. Oza, N. Nair, M. Kumar","doi":"10.1109/POWERCON.2012.6401468","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401468","url":null,"abstract":"This paper presents the laboratory simulation emulating application of a numerical distance relay. It yields a realistic scaled model for a two section radial feeder. Lumped models of transmission lines are constructed, which resemble the actual system. Protection of such realistic feeder enables the students and engineers to get a feel as to how a distance protection works. Provision is also made to change the relay connections from its actual location in the system to the test bench location which helps in testing a relay. The setup as a whole is useful for getting the actual exposure of the complex procedure of co-ordination of relay settings. Advanced technical facilities available in the modern numerical relays are exploited for demonstration purpose in the laboratory environment by hardware simulation. The development was done through senior design projects, thus imparting design exposure to students while reducing the development cost. The work has been done to enhance laboratory curriculum and provide hands-on training to students in laboratory environment.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121865153","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}
With the increasing proportion of photovoltaic power in the microsource, the power quality problem brought by the dynamic process of grid-connected and off-grid cannot be ignored any more. Therefore, this paper puts forward a control method of photovoltaic power flexible grid-connected based on H∞ control. This method combines the photovoltaic power grid-connected filter model and the H∞ control principle based on model matching to design H∞ flexible grid-connected controller. The simulation result shows that under different conditions such as no-load and on-load, the controller can precisely control photovoltaic port voltage to achieve seamless grid connection of the photovoltaic. This controller has the advantages of good dynamic performance and stability.
{"title":"The research on photovoltaic power flexible grid-connected in microgrid based on H∞ control","authors":"Peng Li, Chengjia Liu, Wanping Li, Ziheng Yin, Jianjie Chen, Kaiwen Liu","doi":"10.1109/POWERCON.2012.6401414","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401414","url":null,"abstract":"With the increasing proportion of photovoltaic power in the microsource, the power quality problem brought by the dynamic process of grid-connected and off-grid cannot be ignored any more. Therefore, this paper puts forward a control method of photovoltaic power flexible grid-connected based on H∞ control. This method combines the photovoltaic power grid-connected filter model and the H∞ control principle based on model matching to design H∞ flexible grid-connected controller. The simulation result shows that under different conditions such as no-load and on-load, the controller can precisely control photovoltaic port voltage to achieve seamless grid connection of the photovoltaic. This controller has the advantages of good dynamic performance and stability.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115375445","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401363
Min Zhao, Laijun Chen, Chen Shen, Xiuqiong Huang, C. Zhu
Several microgrids have been constructed and put into operation in China. However, there is no Chinese standard on microgrid published yet. IEEE 1547 series of standards is a uniform, comprehensive and authoritative standard series, which is not only instructive to the interconnection of distributed resources with microgrids, but also plays a pivot role in standardizing microgrid construction and operation in America. This paper conducted a feasibility study of applying IEEE 1547 series of standards for China microgrid. On the basis of present China microgrid projects, macroscopic characters of them are presented and analyzed. The detailed characteristics of microgrids in China and America are compared in four major aspects: elements, topologies, operations and applications. Suggestions about how to modify IEEE 1547 series of standards in order to accommodate China local environment are proposed. The work will help standardization of China microgrids and promote microgrid application in China.
{"title":"A feasibility study of using IEEE 1547 series of standards in China for microgrid","authors":"Min Zhao, Laijun Chen, Chen Shen, Xiuqiong Huang, C. Zhu","doi":"10.1109/POWERCON.2012.6401363","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401363","url":null,"abstract":"Several microgrids have been constructed and put into operation in China. However, there is no Chinese standard on microgrid published yet. IEEE 1547 series of standards is a uniform, comprehensive and authoritative standard series, which is not only instructive to the interconnection of distributed resources with microgrids, but also plays a pivot role in standardizing microgrid construction and operation in America. This paper conducted a feasibility study of applying IEEE 1547 series of standards for China microgrid. On the basis of present China microgrid projects, macroscopic characters of them are presented and analyzed. The detailed characteristics of microgrids in China and America are compared in four major aspects: elements, topologies, operations and applications. Suggestions about how to modify IEEE 1547 series of standards in order to accommodate China local environment are proposed. The work will help standardization of China microgrids and promote microgrid application in China.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122872989","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401269
Liu Qing, Xu Xiaobo, Xu Yan
A kind of main/auxiliary type wide-area backup protection fault location algorithm is proposed to improve the performance of the protection system. The “main” is through strict mathematical calculation to accurately locate the fault location, and the “auxiliary” is using the basic knowledge of power system to predict the fault interval. The “main” and the “auxiliary” run simultaneously. The interval of “auxiliary” should contain the position that the “main” made. On the condition that there is no influence on the running speed, this algorithm more fully utilizes the abundant information that the wide-area networks with the PMU equipment brings, and makes the fault location more accurate and reliable. And many mainstream algorithms can match the fault location algorithm, the algorithm has a very strong commonality. To WSCC9 node system as an example, the simulation results show that the algorithm is effective and correctness protection.
{"title":"Wide area protection algorithm based on main/auxiliary type","authors":"Liu Qing, Xu Xiaobo, Xu Yan","doi":"10.1109/POWERCON.2012.6401269","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401269","url":null,"abstract":"A kind of main/auxiliary type wide-area backup protection fault location algorithm is proposed to improve the performance of the protection system. The “main” is through strict mathematical calculation to accurately locate the fault location, and the “auxiliary” is using the basic knowledge of power system to predict the fault interval. The “main” and the “auxiliary” run simultaneously. The interval of “auxiliary” should contain the position that the “main” made. On the condition that there is no influence on the running speed, this algorithm more fully utilizes the abundant information that the wide-area networks with the PMU equipment brings, and makes the fault location more accurate and reliable. And many mainstream algorithms can match the fault location algorithm, the algorithm has a very strong commonality. To WSCC9 node system as an example, the simulation results show that the algorithm is effective and correctness protection.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129574941","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401304
L. Jing, Xiang Zu-tao, Hou Jun-xian, Ling Ji-min, Guo Qiang
Series capacitors compensation plays a more and more important role in long-distance and large-capacity transmission system, whose model has a significant impact to system stability study. Firstly, both gap protected SC model and linearized model is applied into the available power transmission capability and system stability study in electromechanical transient simulation in this paper. Secondly, it is showed that huge short-circuit current might be caused by using gap protected SC model, and the result of transmission capability and system stability study may deviate in that point. Finally, the comparison between the simulation and theoretical analysis shows that the adoption of linearized model could bring an acceptable result which is close to the electromagnetic transient physical characteristics of SC. The linearized model for MOV-Protected SC is proved to be accurate and effective in a real 500kV SC project, and is recommended in system stability study of SC, and fault current limiter.
{"title":"The impact of model for MOV-protected series capacitors on system stability and available transmission capability","authors":"L. Jing, Xiang Zu-tao, Hou Jun-xian, Ling Ji-min, Guo Qiang","doi":"10.1109/POWERCON.2012.6401304","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401304","url":null,"abstract":"Series capacitors compensation plays a more and more important role in long-distance and large-capacity transmission system, whose model has a significant impact to system stability study. Firstly, both gap protected SC model and linearized model is applied into the available power transmission capability and system stability study in electromechanical transient simulation in this paper. Secondly, it is showed that huge short-circuit current might be caused by using gap protected SC model, and the result of transmission capability and system stability study may deviate in that point. Finally, the comparison between the simulation and theoretical analysis shows that the adoption of linearized model could bring an acceptable result which is close to the electromagnetic transient physical characteristics of SC. The linearized model for MOV-Protected SC is proved to be accurate and effective in a real 500kV SC project, and is recommended in system stability study of SC, and fault current limiter.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128936874","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401424
Fenglong Lu, L. Shang, D. Maksimović, Q. Lv
Addressing challenges related to transportation electrification and grid integration of electric and plug-in hybrid electric vehicles (PHEV), this paper presents results from a large-scale study of real-world PHEV driving and charging patterns. The dataset is based on over 100 PHEVs deployed in various scenarios across the U.S., including more than 39,500 driving trips, over 700,000 km driving distance, and over 7,400 charging events. Data analysis results indicate suboptimal utilization of PHEVs due to insufficient charging. Implications of PHEV proliferation on the power grid both in terms of power demand and the need for charging infrastructure are examined, highlighting the importance of user-vehicle-grid interactions.
{"title":"A large-scale study of PHEV charging","authors":"Fenglong Lu, L. Shang, D. Maksimović, Q. Lv","doi":"10.1109/POWERCON.2012.6401424","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401424","url":null,"abstract":"Addressing challenges related to transportation electrification and grid integration of electric and plug-in hybrid electric vehicles (PHEV), this paper presents results from a large-scale study of real-world PHEV driving and charging patterns. The dataset is based on over 100 PHEVs deployed in various scenarios across the U.S., including more than 39,500 driving trips, over 700,000 km driving distance, and over 7,400 charging events. Data analysis results indicate suboptimal utilization of PHEVs due to insufficient charging. Implications of PHEV proliferation on the power grid both in terms of power demand and the need for charging infrastructure are examined, highlighting the importance of user-vehicle-grid interactions.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"7 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130131509","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401368
Lei Huang, Jian Xu, Yuanzhan Sun, Mangmang Chen, Hao Xu
Application of the short circuit capacity (SCC) for voltage stability analysis and monitoring is proposed in this paper. By analyzing the SCC supplied from grid side and the critical SCC needed by the load side, the voltage stability status of power system can be quantitatively assessed. Therefore, a SCC-based voltage stability index and load margin are utilized to perform the voltage stability monitoring (VSM) task. For online tracing the SCC, a multi-source equivalent model is presented which avoids the impractical assumptions or approximations of system states. Finally, a VSM scheme is carried out for a practical power system in China and the result verifies the effectiveness of the proposed approach.
{"title":"Voltage stability analysis and monitoring based on short circuit capacity","authors":"Lei Huang, Jian Xu, Yuanzhan Sun, Mangmang Chen, Hao Xu","doi":"10.1109/POWERCON.2012.6401368","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401368","url":null,"abstract":"Application of the short circuit capacity (SCC) for voltage stability analysis and monitoring is proposed in this paper. By analyzing the SCC supplied from grid side and the critical SCC needed by the load side, the voltage stability status of power system can be quantitatively assessed. Therefore, a SCC-based voltage stability index and load margin are utilized to perform the voltage stability monitoring (VSM) task. For online tracing the SCC, a multi-source equivalent model is presented which avoids the impractical assumptions or approximations of system states. Finally, a VSM scheme is carried out for a practical power system in China and the result verifies the effectiveness of the proposed approach.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130004543","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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