Pub Date : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405860
Sadegh Esfandiari, Mohammad Ali Labbaf Khaniki, Seyed Hamid Montazeri, J. Milimonfared
A photovoltaic (PV) emulator replicates the exact I-V and P-V output characteristics of a PV module or array. This replication should have occurred in such a way the same output characteristics in different ambient conditions, including different temperature and irradiation levels, mismatching, or partial shading, have been obtained. In this paper, a PV emulator based on a DC-DC converter with a novel control method has been presented. The proposed controller is a fractional PI one optimized with Grasshopper Optimization Algorithm (GOA). It has one degree of freedom more than the conventional PI controller, which is the main advantage of this control approach. Also, a fractional-order lag compensator is used to decrease the output ripple of the converter. On the other hand, the Lambert W function models the PV characteristics which this modeling approach reduces computational burden and time. The simulation results in MATLAB/Simulink validate the performance of the proposed PV emulator.
{"title":"Performance Improvement of Photovoltaic Emulator Using Lambert W Model and Fractional Order PI Controller","authors":"Sadegh Esfandiari, Mohammad Ali Labbaf Khaniki, Seyed Hamid Montazeri, J. Milimonfared","doi":"10.1109/PEDSTC52094.2021.9405860","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405860","url":null,"abstract":"A photovoltaic (PV) emulator replicates the exact I-V and P-V output characteristics of a PV module or array. This replication should have occurred in such a way the same output characteristics in different ambient conditions, including different temperature and irradiation levels, mismatching, or partial shading, have been obtained. In this paper, a PV emulator based on a DC-DC converter with a novel control method has been presented. The proposed controller is a fractional PI one optimized with Grasshopper Optimization Algorithm (GOA). It has one degree of freedom more than the conventional PI controller, which is the main advantage of this control approach. Also, a fractional-order lag compensator is used to decrease the output ripple of the converter. On the other hand, the Lambert W function models the PV characteristics which this modeling approach reduces computational burden and time. The simulation results in MATLAB/Simulink validate the performance of the proposed PV emulator.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123013897","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405938
Ali Akbar Emarloo, F. Mahmouditabar, Abbas Shulaei
This paper investigates and analyzes a new application of two types of controllable series compensators, GCSC and TCSC, in fixing a bus voltage feeding a sensitive load. After introducing the operation principles of the GCSC and TCSC, it is revealed that the studied system provides good performance neither without compensation nor with series compensation with a fixed capacitor. Then, it is shown that if controllable compensators are used, it is possible to prevent voltage variations of the bus that feeds the sensitive load. Finally, a comparison is made between the rating of the components of the GCSC and TCSC, which results indicate the superiority of the former. In this study, all time-domain simulations are done using MATLAB/Simulink.
{"title":"Examination and Comparison of Thyristor and Gate-Controlled Series Capacitors Performance for the Voltage Stabilization of Sensitive Loads","authors":"Ali Akbar Emarloo, F. Mahmouditabar, Abbas Shulaei","doi":"10.1109/PEDSTC52094.2021.9405938","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405938","url":null,"abstract":"This paper investigates and analyzes a new application of two types of controllable series compensators, GCSC and TCSC, in fixing a bus voltage feeding a sensitive load. After introducing the operation principles of the GCSC and TCSC, it is revealed that the studied system provides good performance neither without compensation nor with series compensation with a fixed capacitor. Then, it is shown that if controllable compensators are used, it is possible to prevent voltage variations of the bus that feeds the sensitive load. Finally, a comparison is made between the rating of the components of the GCSC and TCSC, which results indicate the superiority of the former. In this study, all time-domain simulations are done using MATLAB/Simulink.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127649253","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405918
Farnam Farshbaf Roomi, A. Vahedi, S. Mirnikjoo
The proper performance of the permanent magnet synchronous motors leads them to be a potential candidate for various applications. In this regard, the optimum design of them will be important in such a way that the optimization algorithm can have a significant effect on the output characteristics of permanent magnet synchronous motors. Genetic Algorithm is one of well-known optimization tools where convergence and quality of optimum responses depends on its initial population. Therefore, in this paper, Latin Hypercube Sampling assisted Genetic Algorithm combined with Sensitivity analysis has been employed to extract multi-objective optimum design. Finite element modeling results has shown a better electromagnetic performance has been achieved in optimized design comparing to initial one while magnet cost has been greatly reduced.
{"title":"Multi-Objective Optimization of Permanent Magnet Synchronous Motor Based on Sensitivity Analysis and Latin Hypercube Sampling assisted NSGAII","authors":"Farnam Farshbaf Roomi, A. Vahedi, S. Mirnikjoo","doi":"10.1109/PEDSTC52094.2021.9405918","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405918","url":null,"abstract":"The proper performance of the permanent magnet synchronous motors leads them to be a potential candidate for various applications. In this regard, the optimum design of them will be important in such a way that the optimization algorithm can have a significant effect on the output characteristics of permanent magnet synchronous motors. Genetic Algorithm is one of well-known optimization tools where convergence and quality of optimum responses depends on its initial population. Therefore, in this paper, Latin Hypercube Sampling assisted Genetic Algorithm combined with Sensitivity analysis has been employed to extract multi-objective optimum design. Finite element modeling results has shown a better electromagnetic performance has been achieved in optimized design comparing to initial one while magnet cost has been greatly reduced.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117291824","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405859
Moein Ghadrdan, H. Mokhtari
The reliability of power electronic based converters has become increasingly important due to their wide-spread use in industry. An effective method to increase the availability of converters is to use condition monitoring systems for planning scheduled maintenances. This paper provides a method to monitor the condition of IGBTs in a back-to-back converter based on their on-state voltage measurement. Using the proposed system adds limited number of elements to the circuit but can be implemented independent from the converter. Considering the converter topology has made the proposed method applicable for condition monitoring of switches in different back-to-back converters. This advantage significantly reduces the cost of the condition monitoring process making it cost-feasible for cheaper converters. The simulations are performed to prove the performance of the proposed circuit, and the results are presented to confirm the accuracy of the measurement of the on-state voltage.
{"title":"Simple Innovative Method for Online Condition Monitoring of IGBTs in Back-to-Back Converters","authors":"Moein Ghadrdan, H. Mokhtari","doi":"10.1109/PEDSTC52094.2021.9405859","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405859","url":null,"abstract":"The reliability of power electronic based converters has become increasingly important due to their wide-spread use in industry. An effective method to increase the availability of converters is to use condition monitoring systems for planning scheduled maintenances. This paper provides a method to monitor the condition of IGBTs in a back-to-back converter based on their on-state voltage measurement. Using the proposed system adds limited number of elements to the circuit but can be implemented independent from the converter. Considering the converter topology has made the proposed method applicable for condition monitoring of switches in different back-to-back converters. This advantage significantly reduces the cost of the condition monitoring process making it cost-feasible for cheaper converters. The simulations are performed to prove the performance of the proposed circuit, and the results are presented to confirm the accuracy of the measurement of the on-state voltage.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114518786","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405886
Seyed Ali Hosseini, K. Varesi
This paper suggests a Hybrid Switched-Capacitor 9-Level Boost Inverter (HSC9LBI) topology that provides quadruple voltage-gain. Capability of feeding zero or low power-factor load types as well as natural voltage balancing of capacitors are other merits of suggested HSC9LBI. Two half-bridges are utilized to create bipolar voltage-waveform. The suggested HSC9LBI requires single DC source, which results in compact size. Different operational modes have been elaborated. The comparison and simulations results have been presented to verify superiority and suitable functionality of suggested configuration.
{"title":"Hybrid Switched-Capacitor 9-Level Boost Inverter","authors":"Seyed Ali Hosseini, K. Varesi","doi":"10.1109/PEDSTC52094.2021.9405886","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405886","url":null,"abstract":"This paper suggests a Hybrid Switched-Capacitor 9-Level Boost Inverter (HSC9LBI) topology that provides quadruple voltage-gain. Capability of feeding zero or low power-factor load types as well as natural voltage balancing of capacitors are other merits of suggested HSC9LBI. Two half-bridges are utilized to create bipolar voltage-waveform. The suggested HSC9LBI requires single DC source, which results in compact size. Different operational modes have been elaborated. The comparison and simulations results have been presented to verify superiority and suitable functionality of suggested configuration.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114172147","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405862
A. Biglo, S. Farhangi, H. Iman‐Eini
this paper presents a new fully soft switching boost converter with one auxiliary switch that provides Zero Voltage Transition (ZVT) for the main switch in Continues Current Mode (CCM). The auxiliary circuit provides soft switching condition for both switches and all diodes in both turn on and turn off operation that can provide better efficiency and reliability for converter. Furthermore, reverse recovery problems of diodes and EMI noise of switches are alleviated. Simulation tests are conducted in PLECS software and results are included to verify theoretical analyses and feasibility of the proposed soft switching structure.
{"title":"A Novel Zero Voltage Transition soft-switching PWM Boost Converter with low voltage stress","authors":"A. Biglo, S. Farhangi, H. Iman‐Eini","doi":"10.1109/PEDSTC52094.2021.9405862","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405862","url":null,"abstract":"this paper presents a new fully soft switching boost converter with one auxiliary switch that provides Zero Voltage Transition (ZVT) for the main switch in Continues Current Mode (CCM). The auxiliary circuit provides soft switching condition for both switches and all diodes in both turn on and turn off operation that can provide better efficiency and reliability for converter. Furthermore, reverse recovery problems of diodes and EMI noise of switches are alleviated. Simulation tests are conducted in PLECS software and results are included to verify theoretical analyses and feasibility of the proposed soft switching structure.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114720029","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405856
Masood Soleimanifard, A. Y. Varjani
One of the bidirectional converters is the dual active bridge (DAB) structure, which has zero voltage switching (ZVS) capability. However, its ZVS range is limited. Improving the performance of a DAB structure has been studied by researchers. In this paper, using the buck-boost topology, the voltage matching between two sides of the transformer is obtained, and ZVS for a DAB converter in the full range of output power is achieved. In the proposed structure, the single-phase-shift (SPS) switching strategy is used, which is a simple method of a DAB topology. The analysis of the proposed topology is given. To verify the steady-state analysis, this topology is simulated, and simulation results show the correct converter operation.
{"title":"A Dual Active Bridge Converter with Full ZVS Range Using a Buck-Boost Converter","authors":"Masood Soleimanifard, A. Y. Varjani","doi":"10.1109/PEDSTC52094.2021.9405856","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405856","url":null,"abstract":"One of the bidirectional converters is the dual active bridge (DAB) structure, which has zero voltage switching (ZVS) capability. However, its ZVS range is limited. Improving the performance of a DAB structure has been studied by researchers. In this paper, using the buck-boost topology, the voltage matching between two sides of the transformer is obtained, and ZVS for a DAB converter in the full range of output power is achieved. In the proposed structure, the single-phase-shift (SPS) switching strategy is used, which is a simple method of a DAB topology. The analysis of the proposed topology is given. To verify the steady-state analysis, this topology is simulated, and simulation results show the correct converter operation.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121712391","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405971
Seyed Mohamadsaeed Toufighian, J. Faiz, Amirhossein Erfani-Nik
In this paper, a non-salient-pole and salient-pole synchronous generator with static eccentricity fault are simulated using finite element analysis. Different severities of the static eccentricity fault are considered and its effect on flux density, voltage and current is shown and compared with the healthy generator. It was observed that the air gap magnetic flux pattern in the faulty generator is asymmetrical leading to harmonics in the flux and voltage signals. The indexes for fault detection are introduced based on the no-load voltage and full load current signals. These indexes are sensitive to the occurrence of the fault and can be used to detect the static eccentricity fault.
{"title":"Static Eccentricity Fault Detection in Salient and Non-Salient Synchronous Generators Using Harmonic Components","authors":"Seyed Mohamadsaeed Toufighian, J. Faiz, Amirhossein Erfani-Nik","doi":"10.1109/PEDSTC52094.2021.9405971","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405971","url":null,"abstract":"In this paper, a non-salient-pole and salient-pole synchronous generator with static eccentricity fault are simulated using finite element analysis. Different severities of the static eccentricity fault are considered and its effect on flux density, voltage and current is shown and compared with the healthy generator. It was observed that the air gap magnetic flux pattern in the faulty generator is asymmetrical leading to harmonics in the flux and voltage signals. The indexes for fault detection are introduced based on the no-load voltage and full load current signals. These indexes are sensitive to the occurrence of the fault and can be used to detect the static eccentricity fault.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125239820","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405939
F. Mahmouditabar, Mohammad Gorji, A. Vahedi
recently battery powered brushless permanent magnet motor have received more and more attention due to higher reliability, higher efficiency, environmentally friendly, and better performance compared to the gasoline engine for a jet board application. The electric jet board should have fast straights, sharp corners, higher mileage, and superlative acceleration. These features are closely related to electric motor performance. In this paper a 2 kW 4800rpm BLDC motor is designed based on jet board application requirements. The important issue that should be considered in the design of the electric motor is material diversities and manufacturing tolerances in mass production. These manufacturing tolerances will significantly affect the performance of the motor. Therefore, it is necessary to take into account these uncontrollable and unwanted changes in the design process of the electric motor to provide a suitable design and reduce the probability of failure. Therefore in this paper the robust design of brushless permanent magnet motor is carried out using the Taguchi method.
{"title":"Robust Design of BLDC Motor for Jetboard Application","authors":"F. Mahmouditabar, Mohammad Gorji, A. Vahedi","doi":"10.1109/PEDSTC52094.2021.9405939","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405939","url":null,"abstract":"recently battery powered brushless permanent magnet motor have received more and more attention due to higher reliability, higher efficiency, environmentally friendly, and better performance compared to the gasoline engine for a jet board application. The electric jet board should have fast straights, sharp corners, higher mileage, and superlative acceleration. These features are closely related to electric motor performance. In this paper a 2 kW 4800rpm BLDC motor is designed based on jet board application requirements. The important issue that should be considered in the design of the electric motor is material diversities and manufacturing tolerances in mass production. These manufacturing tolerances will significantly affect the performance of the motor. Therefore, it is necessary to take into account these uncontrollable and unwanted changes in the design process of the electric motor to provide a suitable design and reduce the probability of failure. Therefore in this paper the robust design of brushless permanent magnet motor is carried out using the Taguchi method.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116467925","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 : 2021-02-02DOI: 10.1109/PEDSTC52094.2021.9405834
F. Aghaee, N. M. Dehkordi, N. Bayati, A. Hajizadeh
With the wide application of AC Microgrids and increasing penetration of renewable energy sources, due to the wide and effective application of secondary control strategies, these controllers have become a widely used control system for these systems. Moreover, one of the components of these control systems is the communication channel, which usually involves communication general multiplicative noise and delay, which may cause the controller failure in the practical Microgrids and affect the stability of them. A secondary control method by considering the general multiplicative noise and communication delay for a Microgrid is proposed in this study. Moreover, the proposed scheme is capable to accurately control the power-sharing in the Microgrid. This method uses a multi-agent structure with the associated graph theory the solve the general multiplicative noise and delay problem. The simulation result shows the effectivity of the proposed scheme in different situations.
{"title":"Delay and General Multiplicative Noise-Resilient Secondary Frequency and Voltage Control for an Autonomous Microgrid","authors":"F. Aghaee, N. M. Dehkordi, N. Bayati, A. Hajizadeh","doi":"10.1109/PEDSTC52094.2021.9405834","DOIUrl":"https://doi.org/10.1109/PEDSTC52094.2021.9405834","url":null,"abstract":"With the wide application of AC Microgrids and increasing penetration of renewable energy sources, due to the wide and effective application of secondary control strategies, these controllers have become a widely used control system for these systems. Moreover, one of the components of these control systems is the communication channel, which usually involves communication general multiplicative noise and delay, which may cause the controller failure in the practical Microgrids and affect the stability of them. A secondary control method by considering the general multiplicative noise and communication delay for a Microgrid is proposed in this study. Moreover, the proposed scheme is capable to accurately control the power-sharing in the Microgrid. This method uses a multi-agent structure with the associated graph theory the solve the general multiplicative noise and delay problem. The simulation result shows the effectivity of the proposed scheme in different situations.","PeriodicalId":351532,"journal":{"name":"2021 12th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130310245","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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