Pub Date : 2019-12-01DOI: 10.1109/PSC49016.2019.9081550
M. A. Moghadam, R. Noroozian
Today, it is necessary to do condition monitoring of important devices such as transformer, generator and circuit breaker due to the aging phenomenon in the power system. A big TRV1 will occur after interruption on fault current between breaker and transformer. This fault is called TLF2, which causes a big TRV. The purpose of this paper is to model the TRV switchgear module of unite 5 of Rajaee combined cycle power plan with considering its connection to the grid. To get this purpose, at first FRA is measured and then TRV is modeled with a connection of RLC. The results of this model are analyzed in EMTP and MATLAB.
{"title":"Modeling of Transient Recovery Voltage of Rajaee Combined Cycle Power Plant","authors":"M. A. Moghadam, R. Noroozian","doi":"10.1109/PSC49016.2019.9081550","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081550","url":null,"abstract":"Today, it is necessary to do condition monitoring of important devices such as transformer, generator and circuit breaker due to the aging phenomenon in the power system. A big TRV1 will occur after interruption on fault current between breaker and transformer. This fault is called TLF2, which causes a big TRV. The purpose of this paper is to model the TRV switchgear module of unite 5 of Rajaee combined cycle power plan with considering its connection to the grid. To get this purpose, at first FRA is measured and then TRV is modeled with a connection of RLC. The results of this model are analyzed in EMTP and MATLAB.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129596110","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081476
Ali Zarein, A. Mosallanejad, M. Ghazizadeh
Transformerless inverters are most preferred for grid connected photovoltaic (PV) generation system due to higher efficiency and lower cost. Low leakage current and high efficiency are two key indexes for transformerless PV grid-connected inverter. Nevertheless, to observe the safety regulations, the leakage current which reduces the power quality and generates electro-magnetic interference in transformerless PV inverter, has to be addressed carefully. In this paper presents a multilevel transformerless single-phase inverter, which is composed of one H-bridge, one bidirectional switch and one damper circuit to reduce the ground leakage current. Comparison of the proposed inverter configuration and the transformerless single-phase inverters is given based on the power circuit component count. Moreover, analysis of the power losses in the power semiconductor switches of the proposed and several existing topology is given. Finally, proposed topology is simulated by MATLAB/ Simulink software to validate the accuracy of the theoretical analysis.
{"title":"An improved transformerless grid-connected photovoltaic inverter with reduced leakage current and increasing number of output voltage level","authors":"Ali Zarein, A. Mosallanejad, M. Ghazizadeh","doi":"10.1109/PSC49016.2019.9081476","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081476","url":null,"abstract":"Transformerless inverters are most preferred for grid connected photovoltaic (PV) generation system due to higher efficiency and lower cost. Low leakage current and high efficiency are two key indexes for transformerless PV grid-connected inverter. Nevertheless, to observe the safety regulations, the leakage current which reduces the power quality and generates electro-magnetic interference in transformerless PV inverter, has to be addressed carefully. In this paper presents a multilevel transformerless single-phase inverter, which is composed of one H-bridge, one bidirectional switch and one damper circuit to reduce the ground leakage current. Comparison of the proposed inverter configuration and the transformerless single-phase inverters is given based on the power circuit component count. Moreover, analysis of the power losses in the power semiconductor switches of the proposed and several existing topology is given. Finally, proposed topology is simulated by MATLAB/ Simulink software to validate the accuracy of the theoretical analysis.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129921965","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081519
H. Radmanesh, Arsalan Dehbashi
Switching performance and semi-conductors' stresses are among the important factors which affect the operation of power electronic converters. The aim of this paper is to propose and analyze a non-isolated high step-up DC-DC converter in which all semi-conductor devices work in soft switching conditions and a reduced voltage stress appears across the semi-conductors. The proposed converter uses a three-winding transformer in a full-bridge structure. To minimize the voltage stress of the output diodes, they are connected in series with port of the converter. The converter is switched with a phase shift strategy and utilizes the magnetizing and leakage inductances of the transformer to achieve soft switching performance. Furthermore, the secondary and tertiary sides of the transformer supply the output load in an interleaved structure which results in a lower output current ripple. The proposed structure not only reduces the voltage stress, but it also provides high voltage gain. The design consideration equations are presented in the paper. Moreover, a 400W experimental prototype of the converter is presented to validate the operation of the converter.
{"title":"An Integrated Non-Isolated Full-Bridge Converter with Soft Switching","authors":"H. Radmanesh, Arsalan Dehbashi","doi":"10.1109/PSC49016.2019.9081519","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081519","url":null,"abstract":"Switching performance and semi-conductors' stresses are among the important factors which affect the operation of power electronic converters. The aim of this paper is to propose and analyze a non-isolated high step-up DC-DC converter in which all semi-conductor devices work in soft switching conditions and a reduced voltage stress appears across the semi-conductors. The proposed converter uses a three-winding transformer in a full-bridge structure. To minimize the voltage stress of the output diodes, they are connected in series with port of the converter. The converter is switched with a phase shift strategy and utilizes the magnetizing and leakage inductances of the transformer to achieve soft switching performance. Furthermore, the secondary and tertiary sides of the transformer supply the output load in an interleaved structure which results in a lower output current ripple. The proposed structure not only reduces the voltage stress, but it also provides high voltage gain. The design consideration equations are presented in the paper. Moreover, a 400W experimental prototype of the converter is presented to validate the operation of the converter.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131973301","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081463
Saleh Sadeghi Gougheri, H. Jahangir, M. Golkar, A. Moshari
Unit Commitment program is an important study in the operation of power systems which objects to achieve the minimum system operating cost by considering network and unit constraints. In conventional UC, competition between independent units to maximize their profits is not considered. To overcome this shortcoming, in this study, a game theory-based approach has been employed to address the above points. In this regard, we introduce two types of players including power plants and system operator, and solve UC problem with Nash Cournot and Nash Bertrand techniques. Indeed, the main goal of this study is to find a way that maximizes the profit of the system operator by considering the independent units' behavior. To verify the robustness of the proposed method, the introduced UC approach is employed on the IEEE six-bus power system.
{"title":"Unit Commitment with Price Demand Response based on Game Theory Approach","authors":"Saleh Sadeghi Gougheri, H. Jahangir, M. Golkar, A. Moshari","doi":"10.1109/PSC49016.2019.9081463","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081463","url":null,"abstract":"Unit Commitment program is an important study in the operation of power systems which objects to achieve the minimum system operating cost by considering network and unit constraints. In conventional UC, competition between independent units to maximize their profits is not considered. To overcome this shortcoming, in this study, a game theory-based approach has been employed to address the above points. In this regard, we introduce two types of players including power plants and system operator, and solve UC problem with Nash Cournot and Nash Bertrand techniques. Indeed, the main goal of this study is to find a way that maximizes the profit of the system operator by considering the independent units' behavior. To verify the robustness of the proposed method, the introduced UC approach is employed on the IEEE six-bus power system.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"267 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116538725","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081495
M. Karimi, Paria Kargar, K. Varesi
In this paper, two new switched-capacitor based 5 and 9-level inverter topologies have been suggested. Simple structure, natural voltage balancing of capacitors (easy control strategy), low voltage stress on switches as well as step-up capability (proposed 9-level topology) are the main merits of suggested topologies. Also based on comparison results, the suggested topologies utilize decreased devices (switches, gate driver circuits, diodes and capacitors) for producing the same count of levels. The suggested topologies can effectively supply the $R-L$ loads. The simulation results obtained from PSCAD/EMTDC software validates the effectiveness and correct operation of suggested structures.
{"title":"Two Novel Switched-Capacitor Based Multi-Level Inverter Topologies","authors":"M. Karimi, Paria Kargar, K. Varesi","doi":"10.1109/PSC49016.2019.9081495","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081495","url":null,"abstract":"In this paper, two new switched-capacitor based 5 and 9-level inverter topologies have been suggested. Simple structure, natural voltage balancing of capacitors (easy control strategy), low voltage stress on switches as well as step-up capability (proposed 9-level topology) are the main merits of suggested topologies. Also based on comparison results, the suggested topologies utilize decreased devices (switches, gate driver circuits, diodes and capacitors) for producing the same count of levels. The suggested topologies can effectively supply the $R-L$ loads. The simulation results obtained from PSCAD/EMTDC software validates the effectiveness and correct operation of suggested structures.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121665062","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081450
M. Soleimani, H. Torkaman, M. Dankoub
In this paper, a multi-objective optimal design of brushless permanent magnet (PM) motor is presented in terms of power density and efficiency. In this regard, the sizing equation of the design and motor dimensions is investigated. Then, an optimum design based on genetic algorithm (GA) with the purpose of increasing combination of power density and efficiency is introduced. Results obtained from optimization process of brushless PM motor are evaluated using a 3D numerical program based on finite element analysis (FEA). Finally, the comparative study with Bat algorithm (BA) has been done to show the applicability of the design.
{"title":"Multi-objective Optimal Design of Brushless PM Motor for Maximum Power Density and Efficiency","authors":"M. Soleimani, H. Torkaman, M. Dankoub","doi":"10.1109/PSC49016.2019.9081450","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081450","url":null,"abstract":"In this paper, a multi-objective optimal design of brushless permanent magnet (PM) motor is presented in terms of power density and efficiency. In this regard, the sizing equation of the design and motor dimensions is investigated. Then, an optimum design based on genetic algorithm (GA) with the purpose of increasing combination of power density and efficiency is introduced. Results obtained from optimization process of brushless PM motor are evaluated using a 3D numerical program based on finite element analysis (FEA). Finally, the comparative study with Bat algorithm (BA) has been done to show the applicability of the design.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125607030","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081500
Alireza Savabi Nasab, M. Aeini, A. Salemnia, M. Kazemi
Today, with increasing concern about fossil fuel-based energy and its environmental issues, the design of electrical systems has focused on the use of renewable energy sources. One of the most interesting sources of renewable energy is solar energy, but its production and sustainability are simply affected by intermittent working conditions such as changes in radiation, temperature, humidity and minor shadow effects. In this paper, a hybrid energy storage system is used to solve this problem. The main advantage of a hybrid storage system over a battery storage system is the effective use of the characteristics of each element of the storage system. Most of the proposed control strategies for a hybrid energy storage system have high computational burden and difficult implementation. This paper proposes a simple and low cost control strategy using PI controllers and fuzzy logic algorithm, which have a high speed in DC link voltage recovery and higher efficiency for using high charge/discharge cycles of supercapacitors (SCs) and therefore reduces stress on the battery and thus extend its useful life. Finally, the proposed strategy is simulated in MATLAB/simulink and its performance is evaluated.
{"title":"A New Method of Energy Management System in Islanded DC Microgrid Using Fuzzy Logic Controller","authors":"Alireza Savabi Nasab, M. Aeini, A. Salemnia, M. Kazemi","doi":"10.1109/PSC49016.2019.9081500","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081500","url":null,"abstract":"Today, with increasing concern about fossil fuel-based energy and its environmental issues, the design of electrical systems has focused on the use of renewable energy sources. One of the most interesting sources of renewable energy is solar energy, but its production and sustainability are simply affected by intermittent working conditions such as changes in radiation, temperature, humidity and minor shadow effects. In this paper, a hybrid energy storage system is used to solve this problem. The main advantage of a hybrid storage system over a battery storage system is the effective use of the characteristics of each element of the storage system. Most of the proposed control strategies for a hybrid energy storage system have high computational burden and difficult implementation. This paper proposes a simple and low cost control strategy using PI controllers and fuzzy logic algorithm, which have a high speed in DC link voltage recovery and higher efficiency for using high charge/discharge cycles of supercapacitors (SCs) and therefore reduces stress on the battery and thus extend its useful life. Finally, the proposed strategy is simulated in MATLAB/simulink and its performance is evaluated.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"291 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122404377","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081444
P. Elhaminia, E. Hajipour, M. Vakilian
Calculation of the magnetic flux density in magnetic core is an important part of the transformer design process and its equivalent circuit development. By determining the magnetic flux density, the no-load current, no-load losses and magnetic noise of the transformer can be specified. 3D wound core is an efficient proposed transformer core structure which has been employed distribution transformer manufacturers. Magnetic flux density in this type of core has not been investigated in detail, so far. In this paper, magnetic flux density in 3D wound core is investigated in three-phase balanced excitation condition. First, the fundamental equations which should be solved in order to determine the magnetic flux density in the core frames are derived. H-balance equation is one of these fundamental equations which is also a characteristic equation for this type of core. An analytical approach for solving these fundamental equations is then introduced. Finally, the proposed method is verified against experimental results.
{"title":"Magnetic Flux Density Determination in 3D Wound Core Transformer Using H-balance Equation","authors":"P. Elhaminia, E. Hajipour, M. Vakilian","doi":"10.1109/PSC49016.2019.9081444","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081444","url":null,"abstract":"Calculation of the magnetic flux density in magnetic core is an important part of the transformer design process and its equivalent circuit development. By determining the magnetic flux density, the no-load current, no-load losses and magnetic noise of the transformer can be specified. 3D wound core is an efficient proposed transformer core structure which has been employed distribution transformer manufacturers. Magnetic flux density in this type of core has not been investigated in detail, so far. In this paper, magnetic flux density in 3D wound core is investigated in three-phase balanced excitation condition. First, the fundamental equations which should be solved in order to determine the magnetic flux density in the core frames are derived. H-balance equation is one of these fundamental equations which is also a characteristic equation for this type of core. An analytical approach for solving these fundamental equations is then introduced. Finally, the proposed method is verified against experimental results.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"172 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132362491","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081548
A. Soltani
Partial Discharge (PD) intensity assessment in the insulation of high voltage equipment is a very powerful approach for improving the stability of power systems. The evaluation of PD, however, has become complicated in the presence of noise, due to its nature, intrinsic limitations, much diversity, and low amplitude of the generated signals. As one of the most essential parts of the process, de-noising of PD signals can be referred to. Hence, an effective algorithm to do so, Wavelet Transform (WT) has long been utilized, reviewed and studied in the paper. However, that has demonstrated numerous limitations to achieve high performance. Therefore, the present paper seeks to introduce a new method using the curve fitting abilities of Artificial Neural Network (ANN) for de-noising of PD signals. The obtained results for different cases and noise levels, for simulated PD signals, prove the superiority of the proposed method compared to the conventional WT-based algorithms.
{"title":"Employing Artificial Neural Network as a Novel Method for De-noising of Partial Discharge Signals","authors":"A. Soltani","doi":"10.1109/PSC49016.2019.9081548","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081548","url":null,"abstract":"Partial Discharge (PD) intensity assessment in the insulation of high voltage equipment is a very powerful approach for improving the stability of power systems. The evaluation of PD, however, has become complicated in the presence of noise, due to its nature, intrinsic limitations, much diversity, and low amplitude of the generated signals. As one of the most essential parts of the process, de-noising of PD signals can be referred to. Hence, an effective algorithm to do so, Wavelet Transform (WT) has long been utilized, reviewed and studied in the paper. However, that has demonstrated numerous limitations to achieve high performance. Therefore, the present paper seeks to introduce a new method using the curve fitting abilities of Artificial Neural Network (ANN) for de-noising of PD signals. The obtained results for different cases and noise levels, for simulated PD signals, prove the superiority of the proposed method compared to the conventional WT-based algorithms.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121779248","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 : 2019-12-01DOI: 10.1109/PSC49016.2019.9081482
Kasra Khalili, Iraj Pourkeivani, M. Abedi
Active distribution networks operation in islanding mode is one of the concerns of todays power industry operators due to the growth of distributed generations. In addition, it is essential to increase distribution networks resilience in the islanding mode. By constructing microgrids from islanded network based on the self-healing concept, the resilience of remaining distribution network will increase. In this paper, an optimal load shedding algorithm is first implemented due to the amount of available DGs. Then, the active network is divided into a number of microgrids with various boundaries. Two index of self-sufficiency and reliability are used for constructing the microgrids. Finally, the results are tested on IEEE 69 bus distribution system.
{"title":"Micro-grids Resilience Enhancement Using Self-healing Capability","authors":"Kasra Khalili, Iraj Pourkeivani, M. Abedi","doi":"10.1109/PSC49016.2019.9081482","DOIUrl":"https://doi.org/10.1109/PSC49016.2019.9081482","url":null,"abstract":"Active distribution networks operation in islanding mode is one of the concerns of todays power industry operators due to the growth of distributed generations. In addition, it is essential to increase distribution networks resilience in the islanding mode. By constructing microgrids from islanded network based on the self-healing concept, the resilience of remaining distribution network will increase. In this paper, an optimal load shedding algorithm is first implemented due to the amount of available DGs. Then, the active network is divided into a number of microgrids with various boundaries. Two index of self-sufficiency and reliability are used for constructing the microgrids. Finally, the results are tested on IEEE 69 bus distribution system.","PeriodicalId":359817,"journal":{"name":"2019 International Power System Conference (PSC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115160655","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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