Pub Date : 2006-09-01DOI: 10.1109/UPEC.2006.367548
M. Hojo, Y. Fujimura, T. Ohnishi, T. Funabashi
In recent years, various types of fault current limiter (FCL) have been developed, because installation of the FCL will bring a lot of benefits to power system operation. Some power-electronics-based FCLs have been proposed with growing power ratings of converters. It is one of the distinctive features of such FCLs that they can employ some valuable control options in its standby mode. Authors have developed a new type of FCL, which consists of a series reactor and a series-connected voltage source inverter. The inverter compensates a voltage drop across the series reactor and employs some optional controls in a standby mode. But, in case of a system fault, it will be operated in a virtual inductance mode to reduce the fault current. However, the inverter has to handle a large current in the fault current limitation mode. This paper newly proposes that the inverter should be operated in a square-wave mode for fault current limitation in order to reduce the number of switching transitions. In this paper, the operating characteristics of the FCL are confirmed by some simulation studies
{"title":"An Operating Mode of Voltage Source Inverter for Fault Current Limitation","authors":"M. Hojo, Y. Fujimura, T. Ohnishi, T. Funabashi","doi":"10.1109/UPEC.2006.367548","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367548","url":null,"abstract":"In recent years, various types of fault current limiter (FCL) have been developed, because installation of the FCL will bring a lot of benefits to power system operation. Some power-electronics-based FCLs have been proposed with growing power ratings of converters. It is one of the distinctive features of such FCLs that they can employ some valuable control options in its standby mode. Authors have developed a new type of FCL, which consists of a series reactor and a series-connected voltage source inverter. The inverter compensates a voltage drop across the series reactor and employs some optional controls in a standby mode. But, in case of a system fault, it will be operated in a virtual inductance mode to reduce the fault current. However, the inverter has to handle a large current in the fault current limitation mode. This paper newly proposes that the inverter should be operated in a square-wave mode for fault current limitation in order to reduce the number of switching transitions. In this paper, the operating characteristics of the FCL are confirmed by some simulation studies","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125773849","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367773
R. Al-Khannak, B. Bitzer
Power load forecasting is the problem which is solved in this paper under MATLAB environment by constructing a neural network for the power load to find simulated solution with the minimum error square. MATLAB code has been programmed for approximating power load data by using the radial based function (RBF) neural network with Gaussian basis function (GBF's). A developed algorithm to achieve load forecasting application with faster techniques is the aim for this paper. The algorithm is used to enable MATLAB power application to be implemented by multi machines in the grid system. Dividing power job into multi tasks job and then to distribute these tasks to the available idle grid contributor(s) to achieve that application within much less time, cheaper cost and with high accuracy and quality. Grid computing, the new computational distributing technology has been used to enhance the performance of power applications to get benefits of idle grid contributor(s) by sharing computational power resources.
{"title":"Grid Computing for Power and Automation Systems Implementations","authors":"R. Al-Khannak, B. Bitzer","doi":"10.1109/UPEC.2006.367773","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367773","url":null,"abstract":"Power load forecasting is the problem which is solved in this paper under MATLAB environment by constructing a neural network for the power load to find simulated solution with the minimum error square. MATLAB code has been programmed for approximating power load data by using the radial based function (RBF) neural network with Gaussian basis function (GBF's). A developed algorithm to achieve load forecasting application with faster techniques is the aim for this paper. The algorithm is used to enable MATLAB power application to be implemented by multi machines in the grid system. Dividing power job into multi tasks job and then to distribute these tasks to the available idle grid contributor(s) to achieve that application within much less time, cheaper cost and with high accuracy and quality. Grid computing, the new computational distributing technology has been used to enhance the performance of power applications to get benefits of idle grid contributor(s) by sharing computational power resources.","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126418731","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367778
Guodong Li, C. Mao, Jiming Lu, Dan Wang
Compared with the traditional MVDs, including two-level, three-level, hybrid and cascaded multi-level (CML) with poly-phase multi-winding transformer structure, new cascaded multi-level based 6 kV MVDs without input and output transformers is developed. Then, its corresponding multi-input and multi-output nonlinear mathematic model is built in this paper with the phase-shifted carrier pulse modulation (PSCPWM) applied. For the MVDs wider working range, input-state linearization is used to transform the proposed nonlinear model to be linear one. Consequently, the DC capacitor voltage is selected to be the feedback to achieve well voltage sharing among the series connected power units. For the purpose of modular and redundant design, decentralized coordinated control strategy is studied, which lead no message exchange among series connected power units. Furthermore, the active and inactive decouple control is realized in the rectifier of the MVDs. Mathematic simulations show the efficiency of the proposed control scheme
{"title":"Cascaded Multi-Level Based 6kV MVDS without Input and Output Transformers and its Control","authors":"Guodong Li, C. Mao, Jiming Lu, Dan Wang","doi":"10.1109/UPEC.2006.367778","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367778","url":null,"abstract":"Compared with the traditional MVDs, including two-level, three-level, hybrid and cascaded multi-level (CML) with poly-phase multi-winding transformer structure, new cascaded multi-level based 6 kV MVDs without input and output transformers is developed. Then, its corresponding multi-input and multi-output nonlinear mathematic model is built in this paper with the phase-shifted carrier pulse modulation (PSCPWM) applied. For the MVDs wider working range, input-state linearization is used to transform the proposed nonlinear model to be linear one. Consequently, the DC capacitor voltage is selected to be the feedback to achieve well voltage sharing among the series connected power units. For the purpose of modular and redundant design, decentralized coordinated control strategy is studied, which lead no message exchange among series connected power units. Furthermore, the active and inactive decouple control is realized in the rectifier of the MVDs. Mathematic simulations show the efficiency of the proposed control scheme","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126976236","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367729
P. Lyons, P. Taylor, L. Cipcigan, P. Trichakis, A. Wilson
A recent study has indicated that installed micro-generation capacity in the UK could grow to as much as 8 GW by 2015. Clearly, this significant growth will present a number of challenges and opportunities for the electricity industry. Current research in the New and Renewable Energy Group at Durham University seeks to address these issues. This paper describes this research and introduces the concept of an SSEZ (small scale energy zone) and presents a series of IPSA+ models to support this concept. An SSEZ is defined as a distribution network zone containing a significant number of controllable small scale generators, distributed energy storage units and loads. Algorithms will be developed to take an integrated approach to the control of each of these three elements in order to increase the value of SSEG's in terms of economic return, environmental benefit and contribution to network operation. The IPSA+ distribution network models feature high concentrations of SSEG's but are conventional type distribution networks, as opposed to the envisaged active distribution network of an SSEZ. These models are used to evaluate the impact on steady-state voltage rise of a range of SSEG penetrations. This paper describes the SSEZ concept, the IPSA+ models and the laboratory based SSEZ under development at Durham University
{"title":"Small Scale Energy Zones and the Impacts of High Concentrations of Small Scale Embedded Generators","authors":"P. Lyons, P. Taylor, L. Cipcigan, P. Trichakis, A. Wilson","doi":"10.1109/UPEC.2006.367729","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367729","url":null,"abstract":"A recent study has indicated that installed micro-generation capacity in the UK could grow to as much as 8 GW by 2015. Clearly, this significant growth will present a number of challenges and opportunities for the electricity industry. Current research in the New and Renewable Energy Group at Durham University seeks to address these issues. This paper describes this research and introduces the concept of an SSEZ (small scale energy zone) and presents a series of IPSA+ models to support this concept. An SSEZ is defined as a distribution network zone containing a significant number of controllable small scale generators, distributed energy storage units and loads. Algorithms will be developed to take an integrated approach to the control of each of these three elements in order to increase the value of SSEG's in terms of economic return, environmental benefit and contribution to network operation. The IPSA+ distribution network models feature high concentrations of SSEG's but are conventional type distribution networks, as opposed to the envisaged active distribution network of an SSEZ. These models are used to evaluate the impact on steady-state voltage rise of a range of SSEG penetrations. This paper describes the SSEZ concept, the IPSA+ models and the laboratory based SSEZ under development at Durham University","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121034372","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367556
Wu Maolin, Huang Shenghua
This paper describes a method of determination of permanent magnet synchronous machines (PMSM) parameters using simple load test combination with a linear regression model, which can avoid the disadvantages of the traditional load test. In the test, only supply phase voltage, phase current and the rotor position would be required, then the linear regression model was improved to simplify algorithm using QR decompose of matrix. The parameters including e0, R, Ld and Lq obtained by using this technique vary more smoothly, while results obtained by no load test are fluctuating. This method can be used to derive the nonlinear parameter identified model of PMSM in order to apply in an on-line computer controlled environment at the different operating conditions
{"title":"Determination of PMSM Parameters from Simple Load Test","authors":"Wu Maolin, Huang Shenghua","doi":"10.1109/UPEC.2006.367556","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367556","url":null,"abstract":"This paper describes a method of determination of permanent magnet synchronous machines (PMSM) parameters using simple load test combination with a linear regression model, which can avoid the disadvantages of the traditional load test. In the test, only supply phase voltage, phase current and the rotor position would be required, then the linear regression model was improved to simplify algorithm using QR decompose of matrix. The parameters including e0, R, Ld and Lq obtained by using this technique vary more smoothly, while results obtained by no load test are fluctuating. This method can be used to derive the nonlinear parameter identified model of PMSM in order to apply in an on-line computer controlled environment at the different operating conditions","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126922781","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367565
A. H. Ahmad, D. A. Smait
This work is focusing on the following main sights: modeling, design, and implementation of a prototype radial magnetic bearing system. Analysis of the magnetic field parameters in particular the magnetic flux density and the associated magnetic forces by constructing and using finite element method are well considered. A field mapping technique is presented for modeling any other type. In order to designate an active radial magnetic bearings, the designed force and the saturated magnetic flux density are considered as the important parameters to be used. Finite element method is used to evaluate and mapping the field through the model for different cases which in turns show the effective magnetic forces at the desired region
{"title":"Modeling and Design of a Prototype Radial Magnetic Bearing System","authors":"A. H. Ahmad, D. A. Smait","doi":"10.1109/UPEC.2006.367565","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367565","url":null,"abstract":"This work is focusing on the following main sights: modeling, design, and implementation of a prototype radial magnetic bearing system. Analysis of the magnetic field parameters in particular the magnetic flux density and the associated magnetic forces by constructing and using finite element method are well considered. A field mapping technique is presented for modeling any other type. In order to designate an active radial magnetic bearings, the designed force and the saturated magnetic flux density are considered as the important parameters to be used. Finite element method is used to evaluate and mapping the field through the model for different cases which in turns show the effective magnetic forces at the desired region","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126490351","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367621
S. Mahmoud, K.G. Ahmed, R.F. Aboul-Fetouh, F.M. Maayouf
This paper evaluates the potential of demand side management "DSM" (that includes energy conservation and load management activities) in different governmental subsectors in Egypt based on the demand pattern analysis of different types of these subsectors obtained from the time-of-use (TOU) meters and energy audits carried out at some governmental customers. In addition, the impact of DSM in the total governmental sector on the demand forecast and consequently on the power system expansion plan is presented
{"title":"Assessment of DSM Potential in the Governmental Sector in Egypt and its Effect on the National Power System Development","authors":"S. Mahmoud, K.G. Ahmed, R.F. Aboul-Fetouh, F.M. Maayouf","doi":"10.1109/UPEC.2006.367621","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367621","url":null,"abstract":"This paper evaluates the potential of demand side management \"DSM\" (that includes energy conservation and load management activities) in different governmental subsectors in Egypt based on the demand pattern analysis of different types of these subsectors obtained from the time-of-use (TOU) meters and energy audits carried out at some governmental customers. In addition, the impact of DSM in the total governmental sector on the demand forecast and consequently on the power system expansion plan is presented","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"77 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113933231","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367533
R. Pereira, A.J.C. Pereira, C. Ferreira, J. Pinto, F. Barbosa
In recent years, the electricity sector undergoes a restructuring process, operationally and commercially, moving from a vertical integrated model to a market oriented model. With past and current difficulties in building new transmission lines and the significant increase in power transactions associated with competitive electricity markets, maintaining system security, with special regard to voltage instability/collapse issues, is more than ever one of the main concerns for market and system operators. Voltage is most readily controlled by adjustments to reactive power injections in power system. Reactive power can be produced and absorbed by both generation and transmission equipment. System operators, transmission owners, generators, customers, power marketers and government regulators need to pay close attention to voltage control. This paper is devoted to the study of the reactive power support for dynamic voltage stability of a restructured electric power system. A severe contingency situation was simulated. The automatic voltage regulators of the generating units and the mechanically switched shunt capacitors were modelled. The simulation results were obtained using the commercial transient software package EUROSTAG. Finally, some conclusions that provide a better understanding of the voltage collapse phenomena are pointed out.
{"title":"Reactive Power Support in the Dynamic Voltage Stability Assessment of a Restructured Electric Power System","authors":"R. Pereira, A.J.C. Pereira, C. Ferreira, J. Pinto, F. Barbosa","doi":"10.1109/UPEC.2006.367533","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367533","url":null,"abstract":"In recent years, the electricity sector undergoes a restructuring process, operationally and commercially, moving from a vertical integrated model to a market oriented model. With past and current difficulties in building new transmission lines and the significant increase in power transactions associated with competitive electricity markets, maintaining system security, with special regard to voltage instability/collapse issues, is more than ever one of the main concerns for market and system operators. Voltage is most readily controlled by adjustments to reactive power injections in power system. Reactive power can be produced and absorbed by both generation and transmission equipment. System operators, transmission owners, generators, customers, power marketers and government regulators need to pay close attention to voltage control. This paper is devoted to the study of the reactive power support for dynamic voltage stability of a restructured electric power system. A severe contingency situation was simulated. The automatic voltage regulators of the generating units and the mechanically switched shunt capacitors were modelled. The simulation results were obtained using the commercial transient software package EUROSTAG. Finally, some conclusions that provide a better understanding of the voltage collapse phenomena are pointed out.","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128829468","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367547
H. Keivani, M. Askari, F. Kavehnia, Aghdam, A. Mohammadi
A number of modulation strategies are used in multi-level power conversion applications. This paper is focused on novel multi-carrier PWM methods which have been extended for use in cascaded H-bridge multi-level inverter. Novel multi-carrier PWM method can be optimized or balanced the switch utilization in cascaded H-bridge multi-level inverter. Five-level cascaded H-bridge multi-level inverter has been simulated and controlled with the novel multi-carrier PWM proposed in this paper to act as a voltage-source inverter (VSI)
{"title":"Novel Multi-Carrier PWM Method for a Three-Phase Cascaded H-Bridge Multi-Level Inverter","authors":"H. Keivani, M. Askari, F. Kavehnia, Aghdam, A. Mohammadi","doi":"10.1109/UPEC.2006.367547","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367547","url":null,"abstract":"A number of modulation strategies are used in multi-level power conversion applications. This paper is focused on novel multi-carrier PWM methods which have been extended for use in cascaded H-bridge multi-level inverter. Novel multi-carrier PWM method can be optimized or balanced the switch utilization in cascaded H-bridge multi-level inverter. Five-level cascaded H-bridge multi-level inverter has been simulated and controlled with the novel multi-carrier PWM proposed in this paper to act as a voltage-source inverter (VSI)","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115220008","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 : 2006-09-01DOI: 10.1109/UPEC.2006.367769
J. Evans
This paper investigates current unbalance in parallel cable interconnector circuits. Several instances have been observed where an MV switchboard loses supply during a motor starting transient. In each instance the affected switchboard was supplied via two interconnector cables operating in parallel. During motor starting, the transient current was not shared equally between the interconnector red, blue and yellow phases. The protection on each interconnector interpreted the unbalance in the phases as an earth fault and initiated a trip. To establish that the unbalance is not due to load or current transformer spill current, steady-state and transient measurements have been made. Steady-state and transient PSCAD simulations have been performed to investigate possible causes of the unequal current sharing between parallel interconnectors.
{"title":"Unbalance in Parallel Interconnector Circuits","authors":"J. Evans","doi":"10.1109/UPEC.2006.367769","DOIUrl":"https://doi.org/10.1109/UPEC.2006.367769","url":null,"abstract":"This paper investigates current unbalance in parallel cable interconnector circuits. Several instances have been observed where an MV switchboard loses supply during a motor starting transient. In each instance the affected switchboard was supplied via two interconnector cables operating in parallel. During motor starting, the transient current was not shared equally between the interconnector red, blue and yellow phases. The protection on each interconnector interpreted the unbalance in the phases as an earth fault and initiated a trip. To establish that the unbalance is not due to load or current transformer spill current, steady-state and transient measurements have been made. Steady-state and transient PSCAD simulations have been performed to investigate possible causes of the unequal current sharing between parallel interconnectors.","PeriodicalId":184186,"journal":{"name":"Proceedings of the 41st International Universities Power Engineering Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125864179","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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