Pub Date : 2015-07-26DOI: 10.1109/PESGM.2015.7286144
Leandro Rodrigues Manso Silva, C. Duque, P. Ribeiro
With the growing complexity of the electric grid, signal processing has a fundamental importance in characterization, diagnoses and protection. In this paper a brief review of digital signal processing techniques will be done. These techniques are focused in power systems applications, such as: signal compression, harmonic estimation and characterization of load and generation profiles.
{"title":"Recent developments on signal processing for smart grids","authors":"Leandro Rodrigues Manso Silva, C. Duque, P. Ribeiro","doi":"10.1109/PESGM.2015.7286144","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286144","url":null,"abstract":"With the growing complexity of the electric grid, signal processing has a fundamental importance in characterization, diagnoses and protection. In this paper a brief review of digital signal processing techniques will be done. These techniques are focused in power systems applications, such as: signal compression, harmonic estimation and characterization of load and generation profiles.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131354183","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286005
Long Liu, Jin Ma, Z. Dong, Guo Chen, K. Wong
A smart grid is an interdependent system of its electricity network and data communication network. Failures in either of networks could cause cascading failures to both networks and threaten the stability of the whole smart grid system. The interdependence between a power grid and a communication network can be represented using graph theory as unidirectional or directional inter-edges that connect both networks together. Optimizing the allocation of these interlinks can alleviate the severity of cascading failures and effectively enhance the robustness of the system. In this paper, we propose a practical smart grid model as two mutual dependent complex networks with improved inter-links allocation strategy, which is enhancing a fraction of communication nodes with backup power supply. Because of the enhanced communication nodes, the proposed system is more robust against random failures, which is proved by case studies.
{"title":"Influence of enhanced interconnecting links on cascading failures in smart grid","authors":"Long Liu, Jin Ma, Z. Dong, Guo Chen, K. Wong","doi":"10.1109/PESGM.2015.7286005","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286005","url":null,"abstract":"A smart grid is an interdependent system of its electricity network and data communication network. Failures in either of networks could cause cascading failures to both networks and threaten the stability of the whole smart grid system. The interdependence between a power grid and a communication network can be represented using graph theory as unidirectional or directional inter-edges that connect both networks together. Optimizing the allocation of these interlinks can alleviate the severity of cascading failures and effectively enhance the robustness of the system. In this paper, we propose a practical smart grid model as two mutual dependent complex networks with improved inter-links allocation strategy, which is enhancing a fraction of communication nodes with backup power supply. Because of the enhanced communication nodes, the proposed system is more robust against random failures, which is proved by case studies.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132108002","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286294
B. Schettino, C. Duque, P. M. da Silveira
This work presents a comparative study of Least Squares Filter, Kalman Filter and Unscented Kalman Filter for estimating the secondary current phasor distorted due to saturation of Current Transformers (CTs). Several distorted current signals were generated in a Real Time Digital Simulator (RTDS) and embedded in noise. Then, these signals were segmented in two kinds of regions, named saturated and unsaturated regions, with the aid of an auxiliary saturation detecting method. The estimations were performed by the three filters only in the unsaturated regions, where there is no distortion in the signals. The mean estimation errors and its standard deviations were computed, the convergence times were analyzed and a comparative performance evaluation was made. The results obtained have the purpose to assist in choosing the most appropriated estimation method for compensating CT saturation effects.
{"title":"Comparison of estimation methods for compensating the saturation effects in secondary current of Current Transformers","authors":"B. Schettino, C. Duque, P. M. da Silveira","doi":"10.1109/PESGM.2015.7286294","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286294","url":null,"abstract":"This work presents a comparative study of Least Squares Filter, Kalman Filter and Unscented Kalman Filter for estimating the secondary current phasor distorted due to saturation of Current Transformers (CTs). Several distorted current signals were generated in a Real Time Digital Simulator (RTDS) and embedded in noise. Then, these signals were segmented in two kinds of regions, named saturated and unsaturated regions, with the aid of an auxiliary saturation detecting method. The estimations were performed by the three filters only in the unsaturated regions, where there is no distortion in the signals. The mean estimation errors and its standard deviations were computed, the convergence times were analyzed and a comparative performance evaluation was made. The results obtained have the purpose to assist in choosing the most appropriated estimation method for compensating CT saturation effects.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132379296","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286042
M. Yue, Xiao-yu Wang
Probabilistic risk assessment (PRA) techniques are increasingly being used in electric power industry applications for better coping with uncertainties over deterministic approaches. One application where PRA techniques can add value is data analysis for parameters such as outage frequency. Focusing on a probabilistic contingency analysis (PCA), this study examines the issue of obtaining a point estimate of outage statistics by lumping or pooling outage data records together from different sources. A Pearson Chi-square test is adopted to determine the poolability of data, and a lognormal distribution is used to model the data source variability and capture variations of operation and maintenance practices among different utilities. The distribution parameters representing outage frequencies and durations are calculated from the raw outage data. An improved PCA scheme based on the outcomes of this study is proposed and being implemented.
{"title":"Outage data collection and parameter estimation for an improved probabilistic contigency analysis","authors":"M. Yue, Xiao-yu Wang","doi":"10.1109/PESGM.2015.7286042","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286042","url":null,"abstract":"Probabilistic risk assessment (PRA) techniques are increasingly being used in electric power industry applications for better coping with uncertainties over deterministic approaches. One application where PRA techniques can add value is data analysis for parameters such as outage frequency. Focusing on a probabilistic contingency analysis (PCA), this study examines the issue of obtaining a point estimate of outage statistics by lumping or pooling outage data records together from different sources. A Pearson Chi-square test is adopted to determine the poolability of data, and a lognormal distribution is used to model the data source variability and capture variations of operation and maintenance practices among different utilities. The distribution parameters representing outage frequencies and durations are calculated from the raw outage data. An improved PCA scheme based on the outcomes of this study is proposed and being implemented.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130123394","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286203
O. Hafez, Kankar Bhattacharya
This paper presents a novel approach for modeling the 24-hour charging demand profile of a plug-in electric vehicle (PEV) charging station using queuing analysis. The proposed queuing model considers the arrival of PEVs as a non-homogeneous Poisson process with different arrival rates over the day. A distribution optimal power flow (OPF) model is used to study the impact of the PEV charging load of the charging station on distribution system operation. Various objective functions, such as total feeder losses, energy drawn by the local distribution company (LDC) and total cost of energy drawn by LDC are considered in this paper.
{"title":"Modeling of PEV charging load using queuing analysis and its impact on distribution system operation","authors":"O. Hafez, Kankar Bhattacharya","doi":"10.1109/PESGM.2015.7286203","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286203","url":null,"abstract":"This paper presents a novel approach for modeling the 24-hour charging demand profile of a plug-in electric vehicle (PEV) charging station using queuing analysis. The proposed queuing model considers the arrival of PEVs as a non-homogeneous Poisson process with different arrival rates over the day. A distribution optimal power flow (OPF) model is used to study the impact of the PEV charging load of the charging station on distribution system operation. Various objective functions, such as total feeder losses, energy drawn by the local distribution company (LDC) and total cost of energy drawn by LDC are considered in this paper.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130133142","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7285668
Lin-Yu Lu, C. Chu
The task of autonomous power sharing in a micro-grid is usually achieved by decentralized droop control on individual interface power converters, which may suffer from the dependence on output line impedances. Inaccurate reactive power sharing will occur under strongly non-uniform line impedances. Due to inherently distributed and heterogeneous nature of the micro-grid, it becomes an ideal platform for applications of consensus control algorithms. In this paper, the consensus-based droop control with sparse communication network is proposed to overcome the drawback of existing droop control methods. In particular, when line impedances of the power grid are either lossy with the uniform R/X ratio or even pure resistive, the consensus droop control is still an effective method for autonomous real and reactive power sharing. In addition, closed-loop system stability of the proposed consensus-based droop control method can be ensured} by the energy function approach under certain conditions. Real-time simulations of two micro-grid systems are studied to validate the feasibility of the proposed consensus-based droop control method.
{"title":"Consensus-based droop control synthesis for multiple DICs in isolated micro-grids","authors":"Lin-Yu Lu, C. Chu","doi":"10.1109/PESGM.2015.7285668","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7285668","url":null,"abstract":"The task of autonomous power sharing in a micro-grid is usually achieved by decentralized droop control on individual interface power converters, which may suffer from the dependence on output line impedances. Inaccurate reactive power sharing will occur under strongly non-uniform line impedances. Due to inherently distributed and heterogeneous nature of the micro-grid, it becomes an ideal platform for applications of consensus control algorithms. In this paper, the consensus-based droop control with sparse communication network is proposed to overcome the drawback of existing droop control methods. In particular, when line impedances of the power grid are either lossy with the uniform R/X ratio or even pure resistive, the consensus droop control is still an effective method for autonomous real and reactive power sharing. In addition, closed-loop system stability of the proposed consensus-based droop control method can be ensured} by the energy function approach under certain conditions. Real-time simulations of two micro-grid systems are studied to validate the feasibility of the proposed consensus-based droop control method.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130252735","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286390
Jiakun Fang, W. Yao, Zhe Chen, J. Wen, Shijie Cheng
The application of energy storage (ES) in power system is limited due to the high cost of the ES device, which exponentially increases with its capacity. This paper is to improve the saturation-dependent stability of the power system equipped with the energy storage based damping controller (ESDC), and hence, reduce the required size of the ES. The phenomenon that the capacity of ES is smaller than the required value produced by the ESDC, is modeled as actuator saturation using the saturation function. The proposed method is to design an anti-windup compensator (AWC), which in the event of saturation, produces a signal based on the output difference between the ESDC and saturated ES and then augment the signal to the ESDC to alleviate the adverse effect of saturation. The AWC is designed with the reduced- order model of power system and linear matrix inequality. Detailed design procedure is introduced. Case studies based on a modified 4-machine 2-area power system and 10-machine New England power system are carried out to demonstrate the effectiveness of the AWC design method.
{"title":"Design of anti-windup compensation for energy storage based damping controller to enhance power system stability","authors":"Jiakun Fang, W. Yao, Zhe Chen, J. Wen, Shijie Cheng","doi":"10.1109/PESGM.2015.7286390","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286390","url":null,"abstract":"The application of energy storage (ES) in power system is limited due to the high cost of the ES device, which exponentially increases with its capacity. This paper is to improve the saturation-dependent stability of the power system equipped with the energy storage based damping controller (ESDC), and hence, reduce the required size of the ES. The phenomenon that the capacity of ES is smaller than the required value produced by the ESDC, is modeled as actuator saturation using the saturation function. The proposed method is to design an anti-windup compensator (AWC), which in the event of saturation, produces a signal based on the output difference between the ESDC and saturated ES and then augment the signal to the ESDC to alleviate the adverse effect of saturation. The AWC is designed with the reduced- order model of power system and linear matrix inequality. Detailed design procedure is introduced. Case studies based on a modified 4-machine 2-area power system and 10-machine New England power system are carried out to demonstrate the effectiveness of the AWC design method.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130470360","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286502
Guanchen Zhang, Gary Wang, H. Farhangi, A. Palizban
Recent load disaggregation approaches take advantage of artificial intelligent techniques and require low sampling frequency. From utility perspective, intrusive data for training are not available due to privacy and the sampling frequency may be too low to recognize meaningful signatures. This paper proposes a 1-hour frequency disaggregation algorithm for real and reactive energy without knowing what appliances are in a specific house/apartment. The proposed algorithm is particularly developed concerning utility's constraints. A database of typical types of appliances in BC, Canada is built. Based on BC Hydro's smart meter data over a year, the most probable appliances in a specific house/apartment are firstly inferred through likelihood maximization and energy consumption matching. The disaggregation is then implemented by an integer multi-objective Genetic Algorithm tuned by appliance dependence rules. The results show that despite of high uncertainty, more than 50% of energy consumption could be disaggregated for random houses/apartments.
{"title":"Residential electric load disaggregation for low-frequency utility applications","authors":"Guanchen Zhang, Gary Wang, H. Farhangi, A. Palizban","doi":"10.1109/PESGM.2015.7286502","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286502","url":null,"abstract":"Recent load disaggregation approaches take advantage of artificial intelligent techniques and require low sampling frequency. From utility perspective, intrusive data for training are not available due to privacy and the sampling frequency may be too low to recognize meaningful signatures. This paper proposes a 1-hour frequency disaggregation algorithm for real and reactive energy without knowing what appliances are in a specific house/apartment. The proposed algorithm is particularly developed concerning utility's constraints. A database of typical types of appliances in BC, Canada is built. Based on BC Hydro's smart meter data over a year, the most probable appliances in a specific house/apartment are firstly inferred through likelihood maximization and energy consumption matching. The disaggregation is then implemented by an integer multi-objective Genetic Algorithm tuned by appliance dependence rules. The results show that despite of high uncertainty, more than 50% of energy consumption could be disaggregated for random houses/apartments.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134600431","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286369
Hye-Yoon Song, Sung Chan Park, Y. Yoon
Introduction of the smart grid circumstance encourages more demand-side participation in the power system operation. Accordingly, many kinds of the demand response (DR) programs are implemented by electric utilities. Among the DR programs, real-time pricing (RTP) is considered as a good option to utilities because it can directly reflect time-varying production cost to retail price; however, an implementation of RTP requires an automated scheme in customer side especially for the residential customers who have hard time to respond to time-varying price signal manually. This study suggests a customer-side automated scheme result from modifying legacy type appliances into smart appliances. The objective of the modification is minimization of customer's energy cost. In addition, it also reduces the peak-to-average ratio (PAR) on utility perspective. Two types of the SAs are modeled which are do more type SA and store type SA. In design process, the most important philosophy is that customer is not aware of the control. Through the design methodologies presented in this study, customers get financial benefit under RTP while their utility is not reduced. Furthermore, electric utilities can benefit from lowered PAR.
{"title":"A design scheme of the smart appliances to minimize energy cost without reducing customer's utility","authors":"Hye-Yoon Song, Sung Chan Park, Y. Yoon","doi":"10.1109/PESGM.2015.7286369","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286369","url":null,"abstract":"Introduction of the smart grid circumstance encourages more demand-side participation in the power system operation. Accordingly, many kinds of the demand response (DR) programs are implemented by electric utilities. Among the DR programs, real-time pricing (RTP) is considered as a good option to utilities because it can directly reflect time-varying production cost to retail price; however, an implementation of RTP requires an automated scheme in customer side especially for the residential customers who have hard time to respond to time-varying price signal manually. This study suggests a customer-side automated scheme result from modifying legacy type appliances into smart appliances. The objective of the modification is minimization of customer's energy cost. In addition, it also reduces the peak-to-average ratio (PAR) on utility perspective. Two types of the SAs are modeled which are do more type SA and store type SA. In design process, the most important philosophy is that customer is not aware of the control. Through the design methodologies presented in this study, customers get financial benefit under RTP while their utility is not reduced. Furthermore, electric utilities can benefit from lowered PAR.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133916699","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286362
Bin Chen, Hongtao Wang, Xi Cao
Sustained power frequency overvoltage control strategy is an important part of power system restoration plan. The existing sustained overvoltage control methods are based on static network, ignoring the dynamic restoration process. By choosing restoration targets as milestones, the dynamic process can be divided into several restoration sequences, each sequence consists of several restoration operations. In this paper, a dynamic multi-objective sustained overvoltage control model based on the restoration sequence is proposed, which takes the coupling of voltage control schemes at different stages into consideration. The objective functions adapted to the characteristics of restoration process are defined, including the operation risk of restoration sequence, adjusting time of voltage control scheme and voltage deviation of energized buses. The effectiveness of proposed model is verified by the simulation results of dynamic and static optimization under different restoration scenarios in Shandong power grid.
{"title":"Dynamic optimal control of sustained overvoltage during power system restoration process","authors":"Bin Chen, Hongtao Wang, Xi Cao","doi":"10.1109/PESGM.2015.7286362","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286362","url":null,"abstract":"Sustained power frequency overvoltage control strategy is an important part of power system restoration plan. The existing sustained overvoltage control methods are based on static network, ignoring the dynamic restoration process. By choosing restoration targets as milestones, the dynamic process can be divided into several restoration sequences, each sequence consists of several restoration operations. In this paper, a dynamic multi-objective sustained overvoltage control model based on the restoration sequence is proposed, which takes the coupling of voltage control schemes at different stages into consideration. The objective functions adapted to the characteristics of restoration process are defined, including the operation risk of restoration sequence, adjusting time of voltage control scheme and voltage deviation of energized buses. The effectiveness of proposed model is verified by the simulation results of dynamic and static optimization under different restoration scenarios in Shandong power grid.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"71 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131776971","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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