Pub Date : 2013-06-16DOI: 10.1109/ITEC.2013.6573496
Yongbin Chu, Shuo Wang, R. Crosier
This paper first analyzes low switching frequency discrete-time control techniques of an active power filter (APF) of a multifunctional high power electrical vehicle charging station. Based on the analysis, two major factors which greatly degrade the performance of the APF under this control technique, are identified. The first one is that there is always a delay caused by performing digital control algorithm. The second one is that the voltage at the point of common coupling (PCC) is changing during one sampling period. Then, techniques to deal with these problems and improve the performance of the cascaded multilevel inverter based APF are given. These techniques use data collected in previous line cycle to generate reference current and voltage for the APF. Finally, simulation results in Matlab/Simulink are provided to validate these techniques.
{"title":"Improving the performance of an active power filter as part of a multifunctional high power electrical vehicle charging station","authors":"Yongbin Chu, Shuo Wang, R. Crosier","doi":"10.1109/ITEC.2013.6573496","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573496","url":null,"abstract":"This paper first analyzes low switching frequency discrete-time control techniques of an active power filter (APF) of a multifunctional high power electrical vehicle charging station. Based on the analysis, two major factors which greatly degrade the performance of the APF under this control technique, are identified. The first one is that there is always a delay caused by performing digital control algorithm. The second one is that the voltage at the point of common coupling (PCC) is changing during one sampling period. Then, techniques to deal with these problems and improve the performance of the cascaded multilevel inverter based APF are given. These techniques use data collected in previous line cycle to generate reference current and voltage for the APF. Finally, simulation results in Matlab/Simulink are provided to validate these techniques.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"179 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124482097","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573474
Bernardo Peschiera, S. Williamson
For the last two decades, significant improvements in charging technologies have been made. Moreover, novel applications have been proposed and tested, obtaining important and promising results. Inductive charging for electric vehicles (EV) and hybrid electric vehicles (HEV) is one of them. Because of the positive impact that this technology represents, it is important to understand the general characteristics of this novel application. This paper aims to give a general understanding of inductive charging systems for EV and HEV. The explanation of what is an inductive power transfer (IPT) transformer and how electrical power is transferred through air is presented. The review of the electrical characteristics of an IPT transformer is shown: derivation of equations and presentation of the equivalent circuit. The analysis and comparison of two different circuit topologies is also covered (series-series and parallel-parallel). Also, to validate the theoretical concepts, an IPT transformer setup with 5cm of air gap is simulated. The plots and circuit simulations where obtained in MATLAB and SIMULINK respectively.
{"title":"Review and comparison of inductive charging power electronic converter topologies for electric and plug-in hybrid electric vehicles","authors":"Bernardo Peschiera, S. Williamson","doi":"10.1109/ITEC.2013.6573474","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573474","url":null,"abstract":"For the last two decades, significant improvements in charging technologies have been made. Moreover, novel applications have been proposed and tested, obtaining important and promising results. Inductive charging for electric vehicles (EV) and hybrid electric vehicles (HEV) is one of them. Because of the positive impact that this technology represents, it is important to understand the general characteristics of this novel application. This paper aims to give a general understanding of inductive charging systems for EV and HEV. The explanation of what is an inductive power transfer (IPT) transformer and how electrical power is transferred through air is presented. The review of the electrical characteristics of an IPT transformer is shown: derivation of equations and presentation of the equivalent circuit. The analysis and comparison of two different circuit topologies is also covered (series-series and parallel-parallel). Also, to validate the theoretical concepts, an IPT transformer setup with 5cm of air gap is simulated. The plots and circuit simulations where obtained in MATLAB and SIMULINK respectively.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131270346","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573471
A. Ostadi, Mehrdad Kazerani, Shih-Ken Chen
One of the key components of every Electric Vehicle (EV)/Hybrid Electric Vehicle (HEV) is the Energy Storage System (ESS). The most widely-used ESS in electric drivetrains is based on batteries. As the specific power of batteries is normally low, they are hybridized with high-specific power storage elements such as ultra-capacitors in a Hybrid Energy Storage System (HESS) to meet harsh power requirements of the vehicle during acceleration and regenerative braking. This paper provides a thorough literature review on various configurations for interfacing battery and ultra-capacitor units to the DC bus forming a HESS in EV/HEV applications. It also reviews the energy management mechanisms used to split the power demand between battery and ultra-capacitor units.
{"title":"Hybrid Energy Storage System (HESS) in vehicular applications: A review on interfacing battery and ultra-capacitor units","authors":"A. Ostadi, Mehrdad Kazerani, Shih-Ken Chen","doi":"10.1109/ITEC.2013.6573471","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573471","url":null,"abstract":"One of the key components of every Electric Vehicle (EV)/Hybrid Electric Vehicle (HEV) is the Energy Storage System (ESS). The most widely-used ESS in electric drivetrains is based on batteries. As the specific power of batteries is normally low, they are hybridized with high-specific power storage elements such as ultra-capacitors in a Hybrid Energy Storage System (HESS) to meet harsh power requirements of the vehicle during acceleration and regenerative braking. This paper provides a thorough literature review on various configurations for interfacing battery and ultra-capacitor units to the DC bus forming a HESS in EV/HEV applications. It also reviews the energy management mechanisms used to split the power demand between battery and ultra-capacitor units.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126840121","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573507
Adhithya Ravichandran, P. Malysz, S. Sirouspour, A. Emadi
Recent economic incentives have resulted in the proliferation of electric vehicles (EVs). Microgrids are a promising solution to the problem of large-scale EV integration into the electric power system. Furthermore, advances in energy storage technologies have rendered grid energy storage economically viable. In this paper, we review the literature on microgrids, focusing on their role in the integration of EVs, and energy storage into the electricity grid. Commercial ventures in the development of Energy Management Systems are also reviewed. As microgrids become more prevalent, scenarios where multiple microgrids operate in a coordinated fashion may arise. We also review the literature on operation and control of multiple microgrids.
{"title":"The critical role of microgrids in transition to a smarter grid: A technical review","authors":"Adhithya Ravichandran, P. Malysz, S. Sirouspour, A. Emadi","doi":"10.1109/ITEC.2013.6573507","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573507","url":null,"abstract":"Recent economic incentives have resulted in the proliferation of electric vehicles (EVs). Microgrids are a promising solution to the problem of large-scale EV integration into the electric power system. Furthermore, advances in energy storage technologies have rendered grid energy storage economically viable. In this paper, we review the literature on microgrids, focusing on their role in the integration of EVs, and energy storage into the electricity grid. Commercial ventures in the development of Energy Management Systems are also reviewed. As microgrids become more prevalent, scenarios where multiple microgrids operate in a coordinated fashion may arise. We also review the literature on operation and control of multiple microgrids.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123991930","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574525
F. Diba, E. Esmailzadeh
The hybridization of the articulated line-haul heavy duty truck with self-propelled trailer is investigated. In this innovative configuration, the tractor electric hybrid powertrain is arranged in series with the trailer electric motor that provides a share of total traction efforts of the vehicle. This configuration could provide a regenerative braking capability in the trailer and improves the vehicle longitudinal handling and enhances the vehicle lateral stability. Detailed mathematical modeling of the drivetrain components is developed and the energy consumption analyses for typical driving cycles are performed. Simulation results showed the worthwhile capability of the proposed hybrid drivetrain to improve the regenerative braking and enhance the fuel efficiency of the line-haul trucks.
{"title":"A new parallel-series configuration for hybridization of a line-haul truck","authors":"F. Diba, E. Esmailzadeh","doi":"10.1109/ITEC.2013.6574525","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574525","url":null,"abstract":"The hybridization of the articulated line-haul heavy duty truck with self-propelled trailer is investigated. In this innovative configuration, the tractor electric hybrid powertrain is arranged in series with the trailer electric motor that provides a share of total traction efforts of the vehicle. This configuration could provide a regenerative braking capability in the trailer and improves the vehicle longitudinal handling and enhances the vehicle lateral stability. Detailed mathematical modeling of the drivetrain components is developed and the energy consumption analyses for typical driving cycles are performed. Simulation results showed the worthwhile capability of the proposed hybrid drivetrain to improve the regenerative braking and enhance the fuel efficiency of the line-haul trucks.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115334043","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573476
Gianmarco Capano, Maurizio Mozzone, N. Kar
The number of electrical components in vehicles is day by day increasing, requiring a careful dimensioning of the electric system and a correct choice of the components that will have to provide electrical power to the whole system. The amount of electric energy that may be required during the usage of a car is very variable, depending on how many and which loads are active at the moment; the choice of the power generating elements must then be done in a way that guarantees a certain performance, usually relative to the most critical working conditions that may be encountered by the vehicle in its lifetime. In the present paper a study of the fundamental characteristics of the electric system of a vehicle is proposed with particular attention to the two main components, the alternator and the battery; the fundamental equations for the electric power balance in the vehicle are reported and discussed as a preamble for the implementation of a Matlab model able to simulate the behavior of the charge and discharge of a car battery just considering the overall energy balance. The graphical visualization of the trend of the battery charge over many operating cycles allows the user of the program to choose the battery with the most suitable capacity avoiding oversizing or downsizing of this fundamental component. Particular emphasis has been put on the choice of the requirements that the battery charge has to satisfy throughout its lifecycle.
{"title":"Study of the electric power balance in a vehicle for the choice of the battery","authors":"Gianmarco Capano, Maurizio Mozzone, N. Kar","doi":"10.1109/ITEC.2013.6573476","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573476","url":null,"abstract":"The number of electrical components in vehicles is day by day increasing, requiring a careful dimensioning of the electric system and a correct choice of the components that will have to provide electrical power to the whole system. The amount of electric energy that may be required during the usage of a car is very variable, depending on how many and which loads are active at the moment; the choice of the power generating elements must then be done in a way that guarantees a certain performance, usually relative to the most critical working conditions that may be encountered by the vehicle in its lifetime. In the present paper a study of the fundamental characteristics of the electric system of a vehicle is proposed with particular attention to the two main components, the alternator and the battery; the fundamental equations for the electric power balance in the vehicle are reported and discussed as a preamble for the implementation of a Matlab model able to simulate the behavior of the charge and discharge of a car battery just considering the overall energy balance. The graphical visualization of the trend of the battery charge over many operating cycles allows the user of the program to choose the battery with the most suitable capacity avoiding oversizing or downsizing of this fundamental component. Particular emphasis has been put on the choice of the requirements that the battery charge has to satisfy throughout its lifecycle.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124755857","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573485
H. R. Pinkymol, A. I. Maswood, A. Venkataraman
In this paper, a field oriented control of Permanent Magnet Synchronous motor fed from a 3-level Neutral point clamped (NPC) inverter is investigated. With the Space vector modulation (SVM) control, the dc-link capacitors are operated in balanced condition and a true 3-level operation is obtained. The advantages of SVM along with 3-level inverter structure is that, it enhance the performance of PMSM drive with low torque ripple, high efficiency and low harmonic disturbance which makes it suitable for Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) applications among others. The system is co-simulated between Matlab/Simulink® and PSIM.
{"title":"Space vector based field oriented control of Permanent Magnet Synchronous Motor with a 3-level inverter scheme","authors":"H. R. Pinkymol, A. I. Maswood, A. Venkataraman","doi":"10.1109/ITEC.2013.6573485","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573485","url":null,"abstract":"In this paper, a field oriented control of Permanent Magnet Synchronous motor fed from a 3-level Neutral point clamped (NPC) inverter is investigated. With the Space vector modulation (SVM) control, the dc-link capacitors are operated in balanced condition and a true 3-level operation is obtained. The advantages of SVM along with 3-level inverter structure is that, it enhance the performance of PMSM drive with low torque ripple, high efficiency and low harmonic disturbance which makes it suitable for Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) applications among others. The system is co-simulated between Matlab/Simulink® and PSIM.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128903802","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573477
Chenguang Jiang, A. Taylor, Chen Duan, K. Bai
This paper proposed a battery state of charge (SOC) estimation methodology utilizing the Extended Kalman Filter. First, Extended Kalman Filter for Li-ion battery SOC was mathematically designed. Next, simulation models were developed in MATLAB/Simulink, which indicated that the battery SOC estimation with Extended Kalman filter is much more accurate than that from Coulomb Counting method. This is coincident with the mathematical analysis. At the end, a test bench with Lithium-Ion batteries was set up to experimentally verify the theoretical analysis and simulation. Experimental results showed that the average SOC estimation error using Extended Kalman Filter is <;1%.
{"title":"Extended Kalman Filter based battery state of charge(SOC) estimation for electric vehicles","authors":"Chenguang Jiang, A. Taylor, Chen Duan, K. Bai","doi":"10.1109/ITEC.2013.6573477","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573477","url":null,"abstract":"This paper proposed a battery state of charge (SOC) estimation methodology utilizing the Extended Kalman Filter. First, Extended Kalman Filter for Li-ion battery SOC was mathematically designed. Next, simulation models were developed in MATLAB/Simulink, which indicated that the battery SOC estimation with Extended Kalman filter is much more accurate than that from Coulomb Counting method. This is coincident with the mathematical analysis. At the end, a test bench with Lithium-Ion batteries was set up to experimentally verify the theoretical analysis and simulation. Experimental results showed that the average SOC estimation error using Extended Kalman Filter is <;1%.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125749380","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6573509
Junhui Zhao, Yang Wang, Caisheng Wang, F. Lin, L. Wang
The increasing number of plug-in electric vehicles (PEVs) will post new challenges to the existing power grid, as they as a whole will become a substantially large load to the power grid when they are being charged. In this paper, an algorithm is proposed to maximize the injection of PEVs in distribution networks (DNs) without violating power limitations and causing voltage problems. This method is able to optimally calculate the maximum allowed numbers of PEVs in DNs based on the system parameters and load conditions. Voltage stability index, power supply limits, thermal line limits, and power balance equations are taken into account as the constraints of the optimization algorithm. This method is able to provide a clear reference to distribution network operators (DNO) to manage the charging of the PEVs in DNs.
{"title":"Maximizing the penetration of plug-in electric vehicles in distribution network","authors":"Junhui Zhao, Yang Wang, Caisheng Wang, F. Lin, L. Wang","doi":"10.1109/ITEC.2013.6573509","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6573509","url":null,"abstract":"The increasing number of plug-in electric vehicles (PEVs) will post new challenges to the existing power grid, as they as a whole will become a substantially large load to the power grid when they are being charged. In this paper, an algorithm is proposed to maximize the injection of PEVs in distribution networks (DNs) without violating power limitations and causing voltage problems. This method is able to optimally calculate the maximum allowed numbers of PEVs in DNs based on the system parameters and load conditions. Voltage stability index, power supply limits, thermal line limits, and power balance equations are taken into account as the constraints of the optimization algorithm. This method is able to provide a clear reference to distribution network operators (DNO) to manage the charging of the PEVs in DNs.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129225280","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 : 2013-06-16DOI: 10.1109/ITEC.2013.6574521
A. Ostadi, Mehrdad Kazerani, Shih-Ken Chen
Energy Storage System (ESS) is a key component in every Electric Vehicle (EV). The most widely-used ESS in electric powertrains is based on batteries. Optimal sizing of the battery pack in electric vehicles is a crucial requirement as it strongly impacts the manufacturing cost and vehicle weight, thus running cost. This paper addresses optimal sizing of the ESS in a Battery-Electric Vehicle (BEV) based on Particle Swarm Optimization (PSO) method. Simulation results based on the optimally-sized ESS for a vehicle are presented to showcase the resulting system performance and the fact that all constraints are respected.
{"title":"Optimal sizing of the Energy Storage System (ESS) in a Battery-Electric Vehicle","authors":"A. Ostadi, Mehrdad Kazerani, Shih-Ken Chen","doi":"10.1109/ITEC.2013.6574521","DOIUrl":"https://doi.org/10.1109/ITEC.2013.6574521","url":null,"abstract":"Energy Storage System (ESS) is a key component in every Electric Vehicle (EV). The most widely-used ESS in electric powertrains is based on batteries. Optimal sizing of the battery pack in electric vehicles is a crucial requirement as it strongly impacts the manufacturing cost and vehicle weight, thus running cost. This paper addresses optimal sizing of the ESS in a Battery-Electric Vehicle (BEV) based on Particle Swarm Optimization (PSO) method. Simulation results based on the optimally-sized ESS for a vehicle are presented to showcase the resulting system performance and the fact that all constraints are respected.","PeriodicalId":118616,"journal":{"name":"2013 IEEE Transportation Electrification Conference and Expo (ITEC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132330506","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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