Pub Date : 2007-07-01DOI: 10.1109/PCT.2007.4538490
M. Triggianese, F. Liccardo, P. Marino
This paper describes the advantages that can be obtained in ac/dc conversion, when an innovative four-quadrant converter, named synchronous active front-end (SAFE), is employed. The modular system, which increases the availability of the power delivering, can also be designed in order to obtain an improvement of the mission reliability. The reliability of single-AFE topology and the one of a SAFE are here compared. Based on the classical reliability prediction method, this contribution gives a design criteria of the optimum number of the parallel-connected converters and of their switching frequency, in order to match the reliability constrains.
{"title":"Interleaved Active Front-Ends Design Criteria for Reliability improvements","authors":"M. Triggianese, F. Liccardo, P. Marino","doi":"10.1109/PCT.2007.4538490","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538490","url":null,"abstract":"This paper describes the advantages that can be obtained in ac/dc conversion, when an innovative four-quadrant converter, named synchronous active front-end (SAFE), is employed. The modular system, which increases the availability of the power delivering, can also be designed in order to obtain an improvement of the mission reliability. The reliability of single-AFE topology and the one of a SAFE are here compared. Based on the classical reliability prediction method, this contribution gives a design criteria of the optimum number of the parallel-connected converters and of their switching frequency, in order to match the reliability constrains.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134278353","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538661
H. Hatami, Farhad Shahnia, A. Pashaei, S. Hosseini
This paper addresses the issue of modeling and analysis of custom power controllers, power electronic-based equipment aimed at enhancing the reliability and quality of power flows in low voltage distribution networks. A new PWM-based control scheme has been proposed that only requires voltage measurements and no reactive power measurements are required. The operation of the proposed control method is presented for D-STATCOM and DVR. Simulations and analysis are carried out in PSCAD/EMTDC with this control method for two proposed systems. The reliability and robustness of the control scheme in the system response to the voltage disturbances due to system faults or load variations is obviously proved in the simulation results.
{"title":"Investigation on D-STATCOM and DVR Operation for Voltage Control in Distribution Networks with a New Control Strategy","authors":"H. Hatami, Farhad Shahnia, A. Pashaei, S. Hosseini","doi":"10.1109/PCT.2007.4538661","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538661","url":null,"abstract":"This paper addresses the issue of modeling and analysis of custom power controllers, power electronic-based equipment aimed at enhancing the reliability and quality of power flows in low voltage distribution networks. A new PWM-based control scheme has been proposed that only requires voltage measurements and no reactive power measurements are required. The operation of the proposed control method is presented for D-STATCOM and DVR. Simulations and analysis are carried out in PSCAD/EMTDC with this control method for two proposed systems. The reliability and robustness of the control scheme in the system response to the voltage disturbances due to system faults or load variations is obviously proved in the simulation results.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133811799","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538628
J. Kubokawa, Yue Yuan, N. Yorino, Y. Zoka, H. Sasaki, L. Hakim
In nowadays deregulated market, available transfer capability (ATC) is a measure of the network capability for further commercial activity above the already committed uses. This paper deals with the development of an interior point nonlinear programming methodology for evaluating dynamic ATC. By establishing a novel method for integrating transient stability constraints into conventional steady-state ATC problem, we have proposed the dynamic ATC solution methodology using a transient stability constrained OPF (TSCOPF). In actual power system, we have to consider several controller/modeling to evaluate dynamic stability to simulate real system. We have proposed unbalanced three phase model for transmission lines in our TSCOPF. In the proposed method, we can consider any fault sequence on transmission lines and buses. In this paper, we propose an extension of transient stability constrained OPF with consideration of the generator shedding after the fault. The proposed TSCOPF method will be applied to IEEJ EAST10 test system to demonstrate the effectiveness of generator shedding.
{"title":"A Solution of Total Transfer Capability Using Transient Stability Constrained Optimal Power Flow","authors":"J. Kubokawa, Yue Yuan, N. Yorino, Y. Zoka, H. Sasaki, L. Hakim","doi":"10.1109/PCT.2007.4538628","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538628","url":null,"abstract":"In nowadays deregulated market, available transfer capability (ATC) is a measure of the network capability for further commercial activity above the already committed uses. This paper deals with the development of an interior point nonlinear programming methodology for evaluating dynamic ATC. By establishing a novel method for integrating transient stability constraints into conventional steady-state ATC problem, we have proposed the dynamic ATC solution methodology using a transient stability constrained OPF (TSCOPF). In actual power system, we have to consider several controller/modeling to evaluate dynamic stability to simulate real system. We have proposed unbalanced three phase model for transmission lines in our TSCOPF. In the proposed method, we can consider any fault sequence on transmission lines and buses. In this paper, we propose an extension of transient stability constrained OPF with consideration of the generator shedding after the fault. The proposed TSCOPF method will be applied to IEEJ EAST10 test system to demonstrate the effectiveness of generator shedding.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115782265","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538331
D. Cirio, E. Gaglioti, S. Massucco, A. Pitto, F. Silvestro
In operational practice power system security analyses are usually conducted with respect to "credible" contingencies, such as almost all N-l contingencies and some N-2 contingencies suggested by operational experience. On the contrary, extreme contingencies are generally not evaluated, although they can be responsible for major system disturbances and seriously jeopardize system security; within an in-depth analysis they should be analyzed. The paper presents an extensive analysis performed on a realistic network representative of the Italian High Voltage (HV) grid by means of a Dynamic Security Assessment (DSA) application tool integrated in a power system simulator. Besides large sets of N-l and N-2 contingencies, the aforementioned analysis includes also severe and extreme contingencies (in particular N-k contingencies at HV system nodes) and it also evaluates the effects of protection malfunctioning on system security. The contingency list has been created by an ad hoc automatic external procedure linked to the power system simulator. Results highlight the importance of the above extensive analyses also in view of risk- based approaches to security evaluation.
{"title":"An extensive Dynamic Security Assessment analysis on a large realistic electric power system","authors":"D. Cirio, E. Gaglioti, S. Massucco, A. Pitto, F. Silvestro","doi":"10.1109/PCT.2007.4538331","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538331","url":null,"abstract":"In operational practice power system security analyses are usually conducted with respect to \"credible\" contingencies, such as almost all N-l contingencies and some N-2 contingencies suggested by operational experience. On the contrary, extreme contingencies are generally not evaluated, although they can be responsible for major system disturbances and seriously jeopardize system security; within an in-depth analysis they should be analyzed. The paper presents an extensive analysis performed on a realistic network representative of the Italian High Voltage (HV) grid by means of a Dynamic Security Assessment (DSA) application tool integrated in a power system simulator. Besides large sets of N-l and N-2 contingencies, the aforementioned analysis includes also severe and extreme contingencies (in particular N-k contingencies at HV system nodes) and it also evaluates the effects of protection malfunctioning on system security. The contingency list has been created by an ad hoc automatic external procedure linked to the power system simulator. Results highlight the importance of the above extensive analyses also in view of risk- based approaches to security evaluation.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132027388","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538574
Y. Ota, T. Hashiguchi, H. Ukai, M. Sonoda, Y. Miwa, A. Takeuchi
In order to easily monitor the wide-area power system information covering many power producers, suppliers, and power companies, authors have been developed a PMU (phasor measurement unit) based WAMS (wide area measurement system). This WAMS momentarily gather information about the power oscillation affecting the stability of Japanese longitudinal power systems by signal processing of the power outlet phasor. This paper introduces the features of the PMU based WAMS, and an availability of the power outlet phasor is validated by comparing the measurements with actual power station. And as one of the applications, an estimation method of interconnected power system parameters from the monitored power oscillation information is proposed.
为了方便地监测覆盖众多电力生产商、供应商和电力公司的广域电力系统信息，作者开发了一种基于PMU(相量测量单元)的广域测量系统WAMS (wide area measurement system)。该WAMS通过对电源输出相量进行信号处理，瞬时收集影响日本纵向电力系统稳定性的功率振荡信息。介绍了基于PMU的WAMS的特点，并通过与实际电站的测量结果对比，验证了输出相量的有效性。作为应用之一，提出了一种利用监测到的电力振荡信息估计互联电力系统参数的方法。
{"title":"Monitoring of Interconnected Power System Parameters using PMU based WAMS","authors":"Y. Ota, T. Hashiguchi, H. Ukai, M. Sonoda, Y. Miwa, A. Takeuchi","doi":"10.1109/PCT.2007.4538574","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538574","url":null,"abstract":"In order to easily monitor the wide-area power system information covering many power producers, suppliers, and power companies, authors have been developed a PMU (phasor measurement unit) based WAMS (wide area measurement system). This WAMS momentarily gather information about the power oscillation affecting the stability of Japanese longitudinal power systems by signal processing of the power outlet phasor. This paper introduces the features of the PMU based WAMS, and an availability of the power outlet phasor is validated by comparing the measurements with actual power station. And as one of the applications, an estimation method of interconnected power system parameters from the monitored power oscillation information is proposed.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134514867","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538584
P. Choonhapran, G. Balzer
Maintenance of power systems and apparatus is among the most discussed issues at the moment, since utilities require to reduce costs to make their companies competitive. It is obvious that reducing maintenance costs while keeping the high system reliability is not an easy task. In order to redesign the maintenance programs, the failure database and maintenance information must be provided. High voltage (HV) circuit-breakers are one of the most important equipment in power systems. They are subject to many abnormal conditions such as major and minor failures during the lifetimes. In order to study reliability and availability of HV circuit-breakers, these failures have been recorded in terms of database. In this study, the failure database of different types of HV circuit-breakers from 1960s is applied in order to investigate reliability of HV circuit-breakers. The durations between failures were investigated to establish the trend of failure development. Afterwards, cascading reliability model is developed. Finally, the exponential reliability distribution is implemented to simulate the failure development and to study reliability of HV circuit-breakers.
{"title":"Cascading Reliability Model for HV Circuit-Breakers","authors":"P. Choonhapran, G. Balzer","doi":"10.1109/PCT.2007.4538584","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538584","url":null,"abstract":"Maintenance of power systems and apparatus is among the most discussed issues at the moment, since utilities require to reduce costs to make their companies competitive. It is obvious that reducing maintenance costs while keeping the high system reliability is not an easy task. In order to redesign the maintenance programs, the failure database and maintenance information must be provided. High voltage (HV) circuit-breakers are one of the most important equipment in power systems. They are subject to many abnormal conditions such as major and minor failures during the lifetimes. In order to study reliability and availability of HV circuit-breakers, these failures have been recorded in terms of database. In this study, the failure database of different types of HV circuit-breakers from 1960s is applied in order to investigate reliability of HV circuit-breakers. The durations between failures were investigated to establish the trend of failure development. Afterwards, cascading reliability model is developed. Finally, the exponential reliability distribution is implemented to simulate the failure development and to study reliability of HV circuit-breakers.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131673611","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538626
F. Wallin, E. Dotzauer, E. Thorin, E. Dahlquist
The use of top-down models, for load forecasting purposes, has been the dominating method over the last decades. However, there is now a discussion regarding the performance of the top-down models, e.g. in situations with unusual weather conditions due to the lack of historical data. This paper considers an alternative bottom-up approach with a stronger relation to the laws of physics. Electricity companies in Sweden are installing automatic meter reading systems for their customers, and using the consumption data gives new possibilities when adapting the modeling parameters in a bottom-up model for each single customer. A method for analyzing individual consumption series is suggested, where different periods in time is used to divide and identify different parts of the electricity load; base load, heat load and household loads. A review of previous work is presented, and suggestions how to link the load analysis to construction parameters for an individual building is proposed.
{"title":"Automatic Meter Reading Provides Opportunities for New Prognosis and Simulation Methods","authors":"F. Wallin, E. Dotzauer, E. Thorin, E. Dahlquist","doi":"10.1109/PCT.2007.4538626","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538626","url":null,"abstract":"The use of top-down models, for load forecasting purposes, has been the dominating method over the last decades. However, there is now a discussion regarding the performance of the top-down models, e.g. in situations with unusual weather conditions due to the lack of historical data. This paper considers an alternative bottom-up approach with a stronger relation to the laws of physics. Electricity companies in Sweden are installing automatic meter reading systems for their customers, and using the consumption data gives new possibilities when adapting the modeling parameters in a bottom-up model for each single customer. A method for analyzing individual consumption series is suggested, where different periods in time is used to divide and identify different parts of the electricity load; base load, heat load and household loads. A review of previous work is presented, and suggestions how to link the load analysis to construction parameters for an individual building is proposed.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132319059","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538555
S. Natti, M. Kezunovic
Recent trend in maintenance is to optimize the frequency of inspection and repair according to the condition of the equipment being maintained. Condition-based maintenance introduces additional investment in monitoring equipment and analyzing systems. This approach is acceptable only if the benefits are greater than the existing cost of maintenance and additional equipment/software. Low cost "circuit breaker monitors" along with signal processing modules and expert system modules are available to monitor the circuit breaker control circuit signals. This paper presents a model for quantifying the effect of circuit breaker maintenance using the on-line condition data. This model can be used in developing system level maintenance strategies.
{"title":"Model for Quantifying the Effect of Circuit Breaker Maintenance Using Condition-Based Data","authors":"S. Natti, M. Kezunovic","doi":"10.1109/PCT.2007.4538555","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538555","url":null,"abstract":"Recent trend in maintenance is to optimize the frequency of inspection and repair according to the condition of the equipment being maintained. Condition-based maintenance introduces additional investment in monitoring equipment and analyzing systems. This approach is acceptable only if the benefits are greater than the existing cost of maintenance and additional equipment/software. Low cost \"circuit breaker monitors\" along with signal processing modules and expert system modules are available to monitor the circuit breaker control circuit signals. This paper presents a model for quantifying the effect of circuit breaker maintenance using the on-line condition data. This model can be used in developing system level maintenance strategies.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133817042","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538554
A. B. Tronchoni, C. Pretto, V. Licks, M. Rosa, F. Lemos
The advances in area of information technology and applications, specially mobile and wireless technology, are providing conditions to improve data acquisition to be used in power system analysis. These conditions together with computational intelligence methods help provide an improvement in reliability analysis of distribution systems. This paper presents the development of a computational systems using mobile computing and a methodology based on Bayesian Networks to identify forced outage causes. The proposed system was validated using data collection of Brazilian distribution utility.
{"title":"Forced Outage Cause Identification Based on Bayesian Networks","authors":"A. B. Tronchoni, C. Pretto, V. Licks, M. Rosa, F. Lemos","doi":"10.1109/PCT.2007.4538554","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538554","url":null,"abstract":"The advances in area of information technology and applications, specially mobile and wireless technology, are providing conditions to improve data acquisition to be used in power system analysis. These conditions together with computational intelligence methods help provide an improvement in reliability analysis of distribution systems. This paper presents the development of a computational systems using mobile computing and a methodology based on Bayesian Networks to identify forced outage causes. The proposed system was validated using data collection of Brazilian distribution utility.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132698796","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 : 2007-07-01DOI: 10.1109/PCT.2007.4538346
H. Mori, Y. Yamada
This paper proposes a new method for distribution network expansion planning. The proposed method is based on SPEA2 (strength Pareto evolutionary algorithm 2) of multi-objective meta-heuristics. As power systems are deregulated, the power market becomes more competitive. Hence, the cost minimization has been recognized as one of the most important factors in distribution systems. Apart from the cost minimization, the network loss minimization and the power quality are also important. This paper focuses on distribution network expansion planning under new environment with distribution generations (DG). It needs to deal with multi-objective optimization. In this paper, SPEA2 that is effective for evaluating the Pareto solution set is used to solve the multi-objective network expansion planning problem. It has advantage in finding out a set of Pareto solutions with the strategies of using both the archives and the evaluated solution set. The proposed method is successfully applied to the 69-node distribution system with DG units.
{"title":"An Efficient Multi-objective Meta-heuristic Method for Distribution Network Expansion Planning","authors":"H. Mori, Y. Yamada","doi":"10.1109/PCT.2007.4538346","DOIUrl":"https://doi.org/10.1109/PCT.2007.4538346","url":null,"abstract":"This paper proposes a new method for distribution network expansion planning. The proposed method is based on SPEA2 (strength Pareto evolutionary algorithm 2) of multi-objective meta-heuristics. As power systems are deregulated, the power market becomes more competitive. Hence, the cost minimization has been recognized as one of the most important factors in distribution systems. Apart from the cost minimization, the network loss minimization and the power quality are also important. This paper focuses on distribution network expansion planning under new environment with distribution generations (DG). It needs to deal with multi-objective optimization. In this paper, SPEA2 that is effective for evaluating the Pareto solution set is used to solve the multi-objective network expansion planning problem. It has advantage in finding out a set of Pareto solutions with the strategies of using both the archives and the evaluated solution set. The proposed method is successfully applied to the 69-node distribution system with DG units.","PeriodicalId":356805,"journal":{"name":"2007 IEEE Lausanne Power Tech","volume":"686 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132584234","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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