Pub Date : 2011-05-11DOI: 10.1109/POWERENG.2011.6036485
P. Sotorrio-Ruiz, F. J. Sánchez‐Pacheco, J. Heredia-Larrubia, F. Pérez-Hidalgo
Frequently, in investigation, teaching and other environments, it becomes a must to have multiple Pulse Width Modulation (PWM) methods for power inverter systems. Usually, we dispose only one or two possibilities of achievement with many difficulties to change the work environment since normally it involves changes in the circuitry and in the programmable elements. This work describes the achievement of a system that unifies the circuitry around a single microcontroller system and a PC supervisory, where there are different available algorithms of PWM modulation already developed.
{"title":"Fast PWM signals simulation and generation system for investigation and education","authors":"P. Sotorrio-Ruiz, F. J. Sánchez‐Pacheco, J. Heredia-Larrubia, F. Pérez-Hidalgo","doi":"10.1109/POWERENG.2011.6036485","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036485","url":null,"abstract":"Frequently, in investigation, teaching and other environments, it becomes a must to have multiple Pulse Width Modulation (PWM) methods for power inverter systems. Usually, we dispose only one or two possibilities of achievement with many difficulties to change the work environment since normally it involves changes in the circuitry and in the programmable elements. This work describes the achievement of a system that unifies the circuitry around a single microcontroller system and a PC supervisory, where there are different available algorithms of PWM modulation already developed.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"185 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126021609","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036526
I. Colak, Ilhan Garip, Ş. Sağiroğlu, S. Bayhan
In this study a data acquisition card has been designed and implemented to observe and analysis of the voltages and the currents of an alternator under resistive, capacitive and inductive loads. Detail analysis of power, power factor, phase angles and harmonics of the alternator has been done using software written in LabVIEW. The measurement system of voltage and current is opened to remote access. Users can access to the system from any computer having internet connection and make the instantaneous measurements. The experimental results show that the data obtained from power analyzer are very close to remote monitored one. Therefore the system developed can be a useful tool for engineering education purposes as an online course material, a simulator and an online control experiment.
{"title":"Remote monitoring of the load characteristics of synchronous generators","authors":"I. Colak, Ilhan Garip, Ş. Sağiroğlu, S. Bayhan","doi":"10.1109/POWERENG.2011.6036526","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036526","url":null,"abstract":"In this study a data acquisition card has been designed and implemented to observe and analysis of the voltages and the currents of an alternator under resistive, capacitive and inductive loads. Detail analysis of power, power factor, phase angles and harmonics of the alternator has been done using software written in LabVIEW. The measurement system of voltage and current is opened to remote access. Users can access to the system from any computer having internet connection and make the instantaneous measurements. The experimental results show that the data obtained from power analyzer are very close to remote monitored one. Therefore the system developed can be a useful tool for engineering education purposes as an online course material, a simulator and an online control experiment.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127612505","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036538
L. Bisenieks, D. Vinnikov, J. Zakis
This paper presents a new converter topology for a permanent magnet synchronous generator based variable speed wind turbine. Main emphasis is on the combination of a controlled rectifier and a novel step-up isolated DC/DC converter topology proposed by the authors. The topology (controlled rectifier coupled with a quasi-Z-source based galvanically isolated step-up DC/DC converter) is essential to generate regulated DC voltage (400 V DC typical for 230 V AC output) despite wide variations in the output voltage of a wind generator. The operation principle of the proposed topology is described in detail. Experimental results are presented and analyzed.
{"title":"Analysis of operating modes of the novel isolated interface converter for PMSG based wind turbines","authors":"L. Bisenieks, D. Vinnikov, J. Zakis","doi":"10.1109/POWERENG.2011.6036538","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036538","url":null,"abstract":"This paper presents a new converter topology for a permanent magnet synchronous generator based variable speed wind turbine. Main emphasis is on the combination of a controlled rectifier and a novel step-up isolated DC/DC converter topology proposed by the authors. The topology (controlled rectifier coupled with a quasi-Z-source based galvanically isolated step-up DC/DC converter) is essential to generate regulated DC voltage (400 V DC typical for 230 V AC output) despite wide variations in the output voltage of a wind generator. The operation principle of the proposed topology is described in detail. Experimental results are presented and analyzed.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117067644","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}
In the interior permanent magnet synchronous motor (IPMSM) sensorless control system for electric vehicle (EV), in order to improve system robustness and adaptive ability, a novel active-disturbance rejection controller (ADRC) is presented in this paper. In practice, the ADRC parameters are difficult to operate and adjust, so we introduce the fuzzy control, combined with their own characteristics, a self-adapted active disturbance rejection controller with fuzzy control theory is designed. Considering the inner and outer disturbance of the system as the unknown disturbance, and the sensorless control of IPMSM is got by means of the novel ADRC. Simulation results show that the system has strong adaptive ability of disturbance and robust in different speed range, and it has high accurate speed estimation. Feasibility and advantages of the control strategy has been validated in the field of electric vehicle control.
{"title":"IPMSM sensorless control based on fuzzy active-disturbance rejection controller for electric vehicle","authors":"Shoudao Huang, Jiangchuan Kuang, Qing Huang, Keyuan Huang, Jian Gao, Ting Liu","doi":"10.1109/POWERENG.2011.6036495","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036495","url":null,"abstract":"In the interior permanent magnet synchronous motor (IPMSM) sensorless control system for electric vehicle (EV), in order to improve system robustness and adaptive ability, a novel active-disturbance rejection controller (ADRC) is presented in this paper. In practice, the ADRC parameters are difficult to operate and adjust, so we introduce the fuzzy control, combined with their own characteristics, a self-adapted active disturbance rejection controller with fuzzy control theory is designed. Considering the inner and outer disturbance of the system as the unknown disturbance, and the sensorless control of IPMSM is got by means of the novel ADRC. Simulation results show that the system has strong adaptive ability of disturbance and robust in different speed range, and it has high accurate speed estimation. Feasibility and advantages of the control strategy has been validated in the field of electric vehicle control.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121088389","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036537
S. Khosravani, I. Naziri, A. Afshar, M. Karrari
Quality of sensor measurements and their availability is highly important in control of power systems. In this paper, we address fault tolerant control of Large Power Systems (LPS) subject to sensor failure. We assume that observability of subsystem encountering with fault is violated, states cannot be estimated by reliance of faulty subsystem. We use a new method for reconfiguration control of the faults which lead to unobservability of subsystems. The method proposes to augment subsystems to obtaining a new subsystem which is observable, and find best subsystems among the other candidates. By hiding the fault from the controller, it allows the nominal controller to remain in the loop. The proposed approach is applied to IEEE 14-bus test case while interactions are considered in nonlinear form. The Simulation results show that the proposed approach works properly.
{"title":"Fault tolerant control of Large Power Systems subject to sensor failure","authors":"S. Khosravani, I. Naziri, A. Afshar, M. Karrari","doi":"10.1109/POWERENG.2011.6036537","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036537","url":null,"abstract":"Quality of sensor measurements and their availability is highly important in control of power systems. In this paper, we address fault tolerant control of Large Power Systems (LPS) subject to sensor failure. We assume that observability of subsystem encountering with fault is violated, states cannot be estimated by reliance of faulty subsystem. We use a new method for reconfiguration control of the faults which lead to unobservability of subsystems. The method proposes to augment subsystems to obtaining a new subsystem which is observable, and find best subsystems among the other candidates. By hiding the fault from the controller, it allows the nominal controller to remain in the loop. The proposed approach is applied to IEEE 14-bus test case while interactions are considered in nonlinear form. The Simulation results show that the proposed approach works properly.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122504000","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036467
R. Bayindir, Ismail Topaloglu, C. Ocak
In this study, 500 Watts PM BLDC has been investigated using parametric approach method for determining the effect of magnet thickness on motor losses. Copper, iron losses and efficiency variation with magnet thickness calculated and represented graphically. The best performance/efficiency ratio determined versus magnet thickness. 24 slot, 4 pole and inner rotor configuration PM BLDC motor investigated.
{"title":"Investigation of the effect of magnet thickness on motor losses of PM BLDC machines using parametric approach method","authors":"R. Bayindir, Ismail Topaloglu, C. Ocak","doi":"10.1109/POWERENG.2011.6036467","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036467","url":null,"abstract":"In this study, 500 Watts PM BLDC has been investigated using parametric approach method for determining the effect of magnet thickness on motor losses. Copper, iron losses and efficiency variation with magnet thickness calculated and represented graphically. The best performance/efficiency ratio determined versus magnet thickness. 24 slot, 4 pole and inner rotor configuration PM BLDC motor investigated.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115948799","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036431
Segio Sousa, V. Pires, M. Guerreiro
In the paper a field-programmable gate array (FPGA) implementation of a speed controller for the induction machine is presented. This control system is based on the modulation of the rotating field from two others that rotate in opposing directions. To implement this strategy it is used a sliding mode controller. In this way, the controller invert the direction of the field, by inverting the sequence of the three phase stator voltages applied, and in such a way that there is no risk of exceeding the operating currents of the drive. The sliding mode controller is embedded in the core of the Hardware Description Language (HDL) code. As for the FPGA itself, there are several tasks that have to be handled in parallel: calculate the rotor shaft speed from the linear encoder, read the speed set point value from the man-machine interface, apply the commutation switching law from the sliding mode controller, and finally, generate the PWM commands to the inverter. Experimental results from a laboratory prototype system are also presented.
{"title":"FPGA implementation of a speed controller for three phase induction machines based on the inversion of the electromagnetic field","authors":"Segio Sousa, V. Pires, M. Guerreiro","doi":"10.1109/POWERENG.2011.6036431","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036431","url":null,"abstract":"In the paper a field-programmable gate array (FPGA) implementation of a speed controller for the induction machine is presented. This control system is based on the modulation of the rotating field from two others that rotate in opposing directions. To implement this strategy it is used a sliding mode controller. In this way, the controller invert the direction of the field, by inverting the sequence of the three phase stator voltages applied, and in such a way that there is no risk of exceeding the operating currents of the drive. The sliding mode controller is embedded in the core of the Hardware Description Language (HDL) code. As for the FPGA itself, there are several tasks that have to be handled in parallel: calculate the rotor shaft speed from the linear encoder, read the speed set point value from the man-machine interface, apply the commutation switching law from the sliding mode controller, and finally, generate the PWM commands to the inverter. Experimental results from a laboratory prototype system are also presented.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115386926","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036553
M. López, S. Valero, C. Senabre, J. Aparicio
An artificial neural network based on Kohonen self-organizing maps (SOM) and its application to short-term load forecasting (STLF) is presented. The proposed model is capable of forecasting up to 24 hour long profiles, up to 24 hours ahead of the beginning of the period. The input used by the model depends on the available information at the time of the forecast, and it may contain meteorological variables and previous hourly load values. Also, different time frames for the input training data are analyzed. The output of the model is a curve of the forecasted load for the specified period. The test of forecasting 2009 data from the Spanish power system resulted in a 2.67% MAPE (mean absolute percentage error).
{"title":"A SOM neural network approach to load forecasting. Meteorological and time frame influence","authors":"M. López, S. Valero, C. Senabre, J. Aparicio","doi":"10.1109/POWERENG.2011.6036553","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036553","url":null,"abstract":"An artificial neural network based on Kohonen self-organizing maps (SOM) and its application to short-term load forecasting (STLF) is presented. The proposed model is capable of forecasting up to 24 hour long profiles, up to 24 hours ahead of the beginning of the period. The input used by the model depends on the available information at the time of the forecast, and it may contain meteorological variables and previous hourly load values. Also, different time frames for the input training data are analyzed. The output of the model is a curve of the forecasted load for the specified period. The test of forecasting 2009 data from the Spanish power system resulted in a 2.67% MAPE (mean absolute percentage error).","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131102837","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036516
P. Thiemann, C. Mantala, J. Hordler, A. Trautmann, D. Groppe, R. Strothmann, E. Zhou
Sensorless rotor position detection techniques have been gradually developed and proposed, which means that recently available methods can improperly work in some specific conditions. A proper and reliable method is needed. Consequently, a new sensorless rotor position detection technique of permanent magnetic synchronous machines (PMSMs) is proposed in this paper. The proposed method is achieved based on flux linkage signals with access to the neutral point of the machine, which is called direct flux control (DFC) method and it is unnecessary to measure the machine currents. Two simulation environments, MATLB/Simulink and a cooperative simulation with Simplorer and Maxwell, are investigated. The nonlinear magnetization curve (BH curve) is also taken into account, which is impossible to do in the synchronous frame, but possible to process by finite element methods (FEM) implemented in Maxwell. The PMSM model with the nonlinear BH curve can similarly operate as a real PMSM. Moreover, the calculated electric position, done by the proposed method, strongly confirms the possibility to acquire the rotor position for a wide range of speed, including standstill.
{"title":"New sensorless rotor position detection technique of PMSM based on direct flux control","authors":"P. Thiemann, C. Mantala, J. Hordler, A. Trautmann, D. Groppe, R. Strothmann, E. Zhou","doi":"10.1109/POWERENG.2011.6036516","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036516","url":null,"abstract":"Sensorless rotor position detection techniques have been gradually developed and proposed, which means that recently available methods can improperly work in some specific conditions. A proper and reliable method is needed. Consequently, a new sensorless rotor position detection technique of permanent magnetic synchronous machines (PMSMs) is proposed in this paper. The proposed method is achieved based on flux linkage signals with access to the neutral point of the machine, which is called direct flux control (DFC) method and it is unnecessary to measure the machine currents. Two simulation environments, MATLB/Simulink and a cooperative simulation with Simplorer and Maxwell, are investigated. The nonlinear magnetization curve (BH curve) is also taken into account, which is impossible to do in the synchronous frame, but possible to process by finite element methods (FEM) implemented in Maxwell. The PMSM model with the nonlinear BH curve can similarly operate as a real PMSM. Moreover, the calculated electric position, done by the proposed method, strongly confirms the possibility to acquire the rotor position for a wide range of speed, including standstill.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116842407","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 : 2011-05-11DOI: 10.1109/POWERENG.2011.6036483
R. Kadri, J. Gaubert, G. Champenois
Module integrated converters focus many research because they are considered as most promising solutions for grid connection of photovoltaic power generation systems. Most of the proposed approaches relied so far on the use of series string of DC-DC converter to create a high voltage string connected to DC-AC inverter. The boost converter is better in this application. However, under inhomogeneous irradiation, the power generated from each PV module and output DC voltage of each boost becomes unbalanced so that the output currents of each boost are balanced and equal to the string current. In this case the boost converter cannot always deliver all the power from a mixture of shaded panels and those delivering full power. In this paper, a non-dissipative string current diverter is proposed to overcome this problem. One important feature of the proposed circuit herein is the ability to effectively decouple each converter from the rest of the string, making this insensitive to changes in the string current. Hence it is possible to obtain the maximum power from the PV module and allow it to operate at the optimum efficiency. The simulation and experimental results verify that the proposed topology exhibits good performance anyway of inhomogeneous irradiation. On the other hand, the string current diverter circuit does not operate if irradiation is homogeneous. So, in this last condition, the topology efficiency is improved.
{"title":"New converter topology to improve performance of photovoltaic power generation system under shading conditions","authors":"R. Kadri, J. Gaubert, G. Champenois","doi":"10.1109/POWERENG.2011.6036483","DOIUrl":"https://doi.org/10.1109/POWERENG.2011.6036483","url":null,"abstract":"Module integrated converters focus many research because they are considered as most promising solutions for grid connection of photovoltaic power generation systems. Most of the proposed approaches relied so far on the use of series string of DC-DC converter to create a high voltage string connected to DC-AC inverter. The boost converter is better in this application. However, under inhomogeneous irradiation, the power generated from each PV module and output DC voltage of each boost becomes unbalanced so that the output currents of each boost are balanced and equal to the string current. In this case the boost converter cannot always deliver all the power from a mixture of shaded panels and those delivering full power. In this paper, a non-dissipative string current diverter is proposed to overcome this problem. One important feature of the proposed circuit herein is the ability to effectively decouple each converter from the rest of the string, making this insensitive to changes in the string current. Hence it is possible to obtain the maximum power from the PV module and allow it to operate at the optimum efficiency. The simulation and experimental results verify that the proposed topology exhibits good performance anyway of inhomogeneous irradiation. On the other hand, the string current diverter circuit does not operate if irradiation is homogeneous. So, in this last condition, the topology efficiency is improved.","PeriodicalId":166144,"journal":{"name":"2011 International Conference on Power Engineering, Energy and Electrical Drives","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124285781","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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