Pub Date : 2008-05-25DOI: 10.1109/DRPT.2008.4523445
S. N. Keshmiri, M. Ehsan
One of the major problems in liberalized power markets is loss allocation. In this paper, a new method for allocating transmission losses to pool market participants is proposed. The proposed method is fundamentally based on Bialek's "Tracing the flow of electricity" method. The losses is allocated to market participants using the loss weight factors (LWFs) which are obtained from the square current magnitude and Z-bus matrix. The LWF method is based on a solved load flow and strongly emphasizes on current magnitude while considers network topology. The method has been implemented and tested on several networks and one sample summarized in the paper. The results show that the method has an acceptable performance in various situations.
{"title":"Transmission loss allocation using normalized loss weight factors","authors":"S. N. Keshmiri, M. Ehsan","doi":"10.1109/DRPT.2008.4523445","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523445","url":null,"abstract":"One of the major problems in liberalized power markets is loss allocation. In this paper, a new method for allocating transmission losses to pool market participants is proposed. The proposed method is fundamentally based on Bialek's \"Tracing the flow of electricity\" method. The losses is allocated to market participants using the loss weight factors (LWFs) which are obtained from the square current magnitude and Z-bus matrix. The LWF method is based on a solved load flow and strongly emphasizes on current magnitude while considers network topology. The method has been implemented and tested on several networks and one sample summarized in the paper. The results show that the method has an acceptable performance in various situations.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114739422","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 : 2008-05-16DOI: 10.1109/DRPT.2008.4523660
Zhang Wanying, Zhou Youqing, Zhao Wei-ming, Zhnag Xuhong, Zhu Qing, Liu Fuhai, Li Zhongfa
The magnetic shielding type high temperature superconducting fault current limiter, which mainly consists of a primary copper coil, a high-Tc superconducting cylinder as the secondary winding, an iron core and a sub-cooled nitrogen cryostat with a cryocooler, can reduce both the transient and the steady-state fault current significantly, but, the device will reduce the limiting impedance in the HTSCFCL if the magnetizing flux reached the saturation point in the magnetic path having no air gap. A improved magnetic shielding type high temperature superconducting fault current limiter is developed and analysized in the paper. The limiter mainly consists of a copper coil, a superconducting cylinder, a control copper ring, an air gap and the three-legged magnetic core. The copper coil on a superconducting cylinder for generating an AC magnetic field, the superconducting cylinder for shielding the field, the control copper ring for controlling fault currents and the air gap in the three-legged magnetic core for avoiding magnetic saturation under the higher current. The simulation results show the limiter can make the time for recovery shorter, and effectively avoid the reduction of a limiting impedance in the HTSCFCL if the magnetizing flux reached the saturation point.
{"title":"The simulating research on a improved magnetic shielding type of HTSCFCL","authors":"Zhang Wanying, Zhou Youqing, Zhao Wei-ming, Zhnag Xuhong, Zhu Qing, Liu Fuhai, Li Zhongfa","doi":"10.1109/DRPT.2008.4523660","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523660","url":null,"abstract":"The magnetic shielding type high temperature superconducting fault current limiter, which mainly consists of a primary copper coil, a high-Tc superconducting cylinder as the secondary winding, an iron core and a sub-cooled nitrogen cryostat with a cryocooler, can reduce both the transient and the steady-state fault current significantly, but, the device will reduce the limiting impedance in the HTSCFCL if the magnetizing flux reached the saturation point in the magnetic path having no air gap. A improved magnetic shielding type high temperature superconducting fault current limiter is developed and analysized in the paper. The limiter mainly consists of a copper coil, a superconducting cylinder, a control copper ring, an air gap and the three-legged magnetic core. The copper coil on a superconducting cylinder for generating an AC magnetic field, the superconducting cylinder for shielding the field, the control copper ring for controlling fault currents and the air gap in the three-legged magnetic core for avoiding magnetic saturation under the higher current. The simulation results show the limiter can make the time for recovery shorter, and effectively avoid the reduction of a limiting impedance in the HTSCFCL if the magnetizing flux reached the saturation point.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132217528","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 : 2008-05-16DOI: 10.1109/DRPT.2008.4523733
Yan-xia Pan, Jianguo Jiang
A novel magnetic-controlled switcher type fault current limiter (FCL) for high voltage electric network is presented. The current limiting principle of the FCL and control measures is discussed. A 220 V/50 A magnetic-controlled switcher type fault current limiter has been built in order to verify its characteristic. The experimental results shown that under normal state, the FCL has no obvious effect on the power system; under fault state, the current limiting inductance connected in the bias current will be inserted into the fault circuit to limit the fault current. By regulating the bias current, the FCL voltage loss under normal state and the fault current can be adjusted to prescribed level. The experimental results are in accordance with the principle analysis and the FCL has the advantages of simple and reliable structure, flexible control strategy.
{"title":"Experimental study on the magnetic-controlled switcher type fault current limiter","authors":"Yan-xia Pan, Jianguo Jiang","doi":"10.1109/DRPT.2008.4523733","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523733","url":null,"abstract":"A novel magnetic-controlled switcher type fault current limiter (FCL) for high voltage electric network is presented. The current limiting principle of the FCL and control measures is discussed. A 220 V/50 A magnetic-controlled switcher type fault current limiter has been built in order to verify its characteristic. The experimental results shown that under normal state, the FCL has no obvious effect on the power system; under fault state, the current limiting inductance connected in the bias current will be inserted into the fault circuit to limit the fault current. By regulating the bias current, the FCL voltage loss under normal state and the fault current can be adjusted to prescribed level. The experimental results are in accordance with the principle analysis and the FCL has the advantages of simple and reliable structure, flexible control strategy.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124592122","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 : 2008-05-16DOI: 10.1109/DRPT.2008.4523463
Wen-Biaug Yang, Q. Wan, Yi Tang
Congestion management of the power market is the key problem to electric power system operation. To improve the performance of the electricity market, the regional electricity market will become a trend of the power market development. Regional electricity market operation is large in scale .The overall calculation for congestion management needs a lot of work and is hard to meet the actual operational requirements. So zoning further congestion management becomes more necessary. In this paper a new method based on the nodal price deviation is proposed which is used to implement the dynamic zoning according to the different system load level. On the basis of the dynamic zoning, the coordinated auctioning method is applied to the regional congestion management through simulation of the IEEE-14 bus system and results are compared with OPF which is not considering economic means. Simulation of examples demonstrates the validity of the proposed method.
{"title":"Congestion management based on dynamic zoning and coordinated auctioning method","authors":"Wen-Biaug Yang, Q. Wan, Yi Tang","doi":"10.1109/DRPT.2008.4523463","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523463","url":null,"abstract":"Congestion management of the power market is the key problem to electric power system operation. To improve the performance of the electricity market, the regional electricity market will become a trend of the power market development. Regional electricity market operation is large in scale .The overall calculation for congestion management needs a lot of work and is hard to meet the actual operational requirements. So zoning further congestion management becomes more necessary. In this paper a new method based on the nodal price deviation is proposed which is used to implement the dynamic zoning according to the different system load level. On the basis of the dynamic zoning, the coordinated auctioning method is applied to the regional congestion management through simulation of the IEEE-14 bus system and results are compared with OPF which is not considering economic means. Simulation of examples demonstrates the validity of the proposed method.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122316115","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 : 2008-04-06DOI: 10.1109/DRPT.2008.4523801
Cui Xue-shen, Yang Yulei, Zhou Zhenhua, Zhao Hai-sen
The residual voltage of asynchronous motors after AC dump(RVACD) could have result in inrush current and inrush torque when asynchronous motors were reclosed or reswitched on the alternate power source, which would have cause damage to motors or bring power source problems such as mal-operation of feeder protection and voltage sag, etc. In this paper we built the space vector based model of motors to research the RVACD so as to thoroughly analyze the varying laws of electrical qualities and magnetic field after dumping, deduce the analytical expression of residual voltage of one motor, and get the solution for the group of asynchronous motors. The inrush current and torque are presented for power source to be restored at different moment after dumping.
{"title":"The research on residual voltage of asynchronous motors and its impact on power restoration","authors":"Cui Xue-shen, Yang Yulei, Zhou Zhenhua, Zhao Hai-sen","doi":"10.1109/DRPT.2008.4523801","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523801","url":null,"abstract":"The residual voltage of asynchronous motors after AC dump(RVACD) could have result in inrush current and inrush torque when asynchronous motors were reclosed or reswitched on the alternate power source, which would have cause damage to motors or bring power source problems such as mal-operation of feeder protection and voltage sag, etc. In this paper we built the space vector based model of motors to research the RVACD so as to thoroughly analyze the varying laws of electrical qualities and magnetic field after dumping, deduce the analytical expression of residual voltage of one motor, and get the solution for the group of asynchronous motors. The inrush current and torque are presented for power source to be restored at different moment after dumping.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115501628","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 : 2008-04-06DOI: 10.1109/DRPT.2008.4523542
W. Nakawiro, I. Erlich
This paper presents an application of Artificial Neural Network (ANN) for monitoring power system voltage stability. The training of ANN is accomplished by adapting information received from local and remote measurements as inputs and fast indicators providing voltage stability information of the whole power system and one at each particular bus as outputs. The use of feature reduction techniques can decrease the number of features required and thus reduce the number of system quantities needed to be measured and transmitted. In this paper, the effectiveness of the proposed algorithm is tested under a large number of random operating conditions on the standard IEEE 14-bus system and the results are encouraging. Fast performance and accurate evaluation of voltage stability indicators have been obtained. Finally, the idea of applying load shedding based on voltage stability indicator as one of potential countermeasures is described.
{"title":"Online voltage stability monitoring using Artificial Neural Network","authors":"W. Nakawiro, I. Erlich","doi":"10.1109/DRPT.2008.4523542","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523542","url":null,"abstract":"This paper presents an application of Artificial Neural Network (ANN) for monitoring power system voltage stability. The training of ANN is accomplished by adapting information received from local and remote measurements as inputs and fast indicators providing voltage stability information of the whole power system and one at each particular bus as outputs. The use of feature reduction techniques can decrease the number of features required and thus reduce the number of system quantities needed to be measured and transmitted. In this paper, the effectiveness of the proposed algorithm is tested under a large number of random operating conditions on the standard IEEE 14-bus system and the results are encouraging. Fast performance and accurate evaluation of voltage stability indicators have been obtained. Finally, the idea of applying load shedding based on voltage stability indicator as one of potential countermeasures is described.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115757946","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 : 2008-04-06DOI: 10.1109/DRPT.2008.4523802
Ye Wu, Xinyan Fang
An optimal algorithm to assess the effectiveness of black-start schemes of electric power system is proposed in this paper. Based on the Group Standard Method (GSM) model, this algorithm could analyze the important factors of black-start process, take them as input or output indexes of the model and sort the black-start plans by relative efficiency values of decisionmaking units (DMUs). Afterwards, the best scheme with first priority is recommended to dispatchers. An instance of a real electric power grid proved it feasible.
{"title":"GSM based algorithm for decision-support expert system to assess black-start plans","authors":"Ye Wu, Xinyan Fang","doi":"10.1109/DRPT.2008.4523802","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523802","url":null,"abstract":"An optimal algorithm to assess the effectiveness of black-start schemes of electric power system is proposed in this paper. Based on the Group Standard Method (GSM) model, this algorithm could analyze the important factors of black-start process, take them as input or output indexes of the model and sort the black-start plans by relative efficiency values of decisionmaking units (DMUs). Afterwards, the best scheme with first priority is recommended to dispatchers. An instance of a real electric power grid proved it feasible.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116658250","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 : 2008-04-06DOI: 10.1109/DRPT.2008.4523745
Mao Peng, Bai Richang
The optimizing model of fault diagnosis for power network is formulated as a 0-1 integer programming problem. The fault equipments can be determined by means of the refined mathematical manipulation. We make a deep study of the present optimizing models and their disadvantages, especially the problems of inconsequence and non-uniqueness of some diagnosis results, and find the cause of the non-uniqueness lies in the fact that the model only takes the influence of each protection into account and ignores the conjunct influence of main and back up protections. On the basis of this point, taking a general view of the configuration characteristics of present secondary systems and the features of the diagnosis information, an improved optimizing model of fault diagnosis for power network is proposed in this paper. The particularity of breaker malfunction protection is taken into account in the new model. The expecting status functions of the equipments are redefined. The preconditioning of the raw data for fault diagnosis and the realization of the system are also explicated briefly. Theoretic analysis and instance verifications indicate that the new model is more reasonable and the diagnosis results are exacter.
{"title":"Studies on the optimizing model of fault diagnosis for power network","authors":"Mao Peng, Bai Richang","doi":"10.1109/DRPT.2008.4523745","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523745","url":null,"abstract":"The optimizing model of fault diagnosis for power network is formulated as a 0-1 integer programming problem. The fault equipments can be determined by means of the refined mathematical manipulation. We make a deep study of the present optimizing models and their disadvantages, especially the problems of inconsequence and non-uniqueness of some diagnosis results, and find the cause of the non-uniqueness lies in the fact that the model only takes the influence of each protection into account and ignores the conjunct influence of main and back up protections. On the basis of this point, taking a general view of the configuration characteristics of present secondary systems and the features of the diagnosis information, an improved optimizing model of fault diagnosis for power network is proposed in this paper. The particularity of breaker malfunction protection is taken into account in the new model. The expecting status functions of the equipments are redefined. The preconditioning of the raw data for fault diagnosis and the realization of the system are also explicated briefly. Theoretic analysis and instance verifications indicate that the new model is more reasonable and the diagnosis results are exacter.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117117179","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 : 2008-04-06DOI: 10.1109/DRPT.2008.4523721
Genghui Zeng, Z. Cai, Minghui Huang, Zhiyao Liu
Zero sequence pilot protection is widely used in high-voltage electrical power system as a main protection for transmission lines. However, zero sequence pilot protection may misoperate under the influence of zero sequence mutual inductance. A misoperation of zero sequence pilot protection of same-pole transmission lines occurred in Guangdong power grid. In this paper, the misoperation is described in detail first. Then, the reason that zero sequence mutual inductance between same- pole transmission lines leads to the misoperation of zero sequence pilot protection are summarized. Some typical power network topologies that may cause misoperation of zero sequence pilot protection are listed. Finally, several countermeasures which can eliminate the misoperation of zero sequence pilot protection are proposed.
{"title":"Analysis and countermeasures of misoperation of zero sequence pilot protection on circuit lines of same pole","authors":"Genghui Zeng, Z. Cai, Minghui Huang, Zhiyao Liu","doi":"10.1109/DRPT.2008.4523721","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523721","url":null,"abstract":"Zero sequence pilot protection is widely used in high-voltage electrical power system as a main protection for transmission lines. However, zero sequence pilot protection may misoperate under the influence of zero sequence mutual inductance. A misoperation of zero sequence pilot protection of same-pole transmission lines occurred in Guangdong power grid. In this paper, the misoperation is described in detail first. Then, the reason that zero sequence mutual inductance between same- pole transmission lines leads to the misoperation of zero sequence pilot protection are summarized. Some typical power network topologies that may cause misoperation of zero sequence pilot protection are listed. Finally, several countermeasures which can eliminate the misoperation of zero sequence pilot protection are proposed.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121150775","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 : 2008-04-06DOI: 10.1109/DRPT.2008.4523873
Deming Zhu, Xin Qiu, N. Zhou, Yangguang Yan
Distributed windings have been extensively equipped in permanent magnet synchronous machine (PMSM) because of their inherent sinusoidal electromotive force (EMF) waveform. Recent work by the authors shows the differences of winding factors between non-overlapping windings and its distributed windings counterpart. The winding factors of non- overlapping concentrated windings eliminate only part of EMF waveform harmonics. Latter suggestion is that with careful design of slot width, the EMF waveform of non-overlapping windings can also be sinusoidal. Finite element analysis model and experiment results validate the analysis in this paper.
{"title":"A comparative study of winding factors between distributed windings and non-overlapping concentrated windings","authors":"Deming Zhu, Xin Qiu, N. Zhou, Yangguang Yan","doi":"10.1109/DRPT.2008.4523873","DOIUrl":"https://doi.org/10.1109/DRPT.2008.4523873","url":null,"abstract":"Distributed windings have been extensively equipped in permanent magnet synchronous machine (PMSM) because of their inherent sinusoidal electromotive force (EMF) waveform. Recent work by the authors shows the differences of winding factors between non-overlapping windings and its distributed windings counterpart. The winding factors of non- overlapping concentrated windings eliminate only part of EMF waveform harmonics. Latter suggestion is that with careful design of slot width, the EMF waveform of non-overlapping windings can also be sinusoidal. Finite element analysis model and experiment results validate the analysis in this paper.","PeriodicalId":240420,"journal":{"name":"2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127100569","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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