Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065905
A. Chub, Kosenko Roman, O. Korkh, D. Vinnikov, S. Kouro
Two-stage photovoltaic (PV) microinverters with a buck-boost front-end converter can provide unparalleled performance under shading conditions. However, their efficiency curve is not monotonic across the input voltage range. As a result, it is hard to predict energy production under known weather conditions. The proposed methodology utilizes interpolation of microinverter efficiency based on the experimental efficiency look-up table. Modeling of the maximum power point of a PV module based on the Lambert W function could be combined with the interpolated efficiency to estimate energy produced by a microinverter. The proposed methodology requires only two synchronized datasets, solar irradiance and ambient temperature, as the input variables.
{"title":"Energy Yield Assessment Methodology for Photovoltaic Microinverters","authors":"A. Chub, Kosenko Roman, O. Korkh, D. Vinnikov, S. Kouro","doi":"10.1109/COBEP/SPEC44138.2019.9065905","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065905","url":null,"abstract":"Two-stage photovoltaic (PV) microinverters with a buck-boost front-end converter can provide unparalleled performance under shading conditions. However, their efficiency curve is not monotonic across the input voltage range. As a result, it is hard to predict energy production under known weather conditions. The proposed methodology utilizes interpolation of microinverter efficiency based on the experimental efficiency look-up table. Modeling of the maximum power point of a PV module based on the Lambert W function could be combined with the interpolated efficiency to estimate energy produced by a microinverter. The proposed methodology requires only two synchronized datasets, solar irradiance and ambient temperature, as the input variables.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"47 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90888403","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/COBEP/SPEC44138.2019.9065296
Gabriel Ubirajara de Carvalho, Gustavo Weber Denardin, R. Cardoso, C. F. Moraes
This paper presents the design, analysis and experimental testing of a SRF-PLL based algorithm for positive-sequence synchrophasor measurements in compliance with the IEEE C37.118.1-2011 and C37.118.1a-2014 standards. The proposed approach consists of a three-stage algorithm, being the first one a three-phase demodulation, which detach the positive-sequence from the negative sequence signal in the frequency domain, as well as removes the zero sequence. The second stage is a finite impulse response filter (FIR) that is applied in order to improve the noise and interference rejection. Such class of digital filters was chosen by its characteristics of linear phase and constant group delay. Finally, the last stage is carried out by a synchronous reference frame phase-locked loop featuring magnitude normalization and proportional-integral controller, which estimates amplitude, phase, frequency and rate of change of frequency. The experimental results obtained by a test platform show that steady-state criteria are met.
{"title":"Design and Test of a SRF-PLL Based Algorithm for Positive-Sequence Synchrophasor Measurements","authors":"Gabriel Ubirajara de Carvalho, Gustavo Weber Denardin, R. Cardoso, C. F. Moraes","doi":"10.1109/COBEP/SPEC44138.2019.9065296","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065296","url":null,"abstract":"This paper presents the design, analysis and experimental testing of a SRF-PLL based algorithm for positive-sequence synchrophasor measurements in compliance with the IEEE C37.118.1-2011 and C37.118.1a-2014 standards. The proposed approach consists of a three-stage algorithm, being the first one a three-phase demodulation, which detach the positive-sequence from the negative sequence signal in the frequency domain, as well as removes the zero sequence. The second stage is a finite impulse response filter (FIR) that is applied in order to improve the noise and interference rejection. Such class of digital filters was chosen by its characteristics of linear phase and constant group delay. Finally, the last stage is carried out by a synchronous reference frame phase-locked loop featuring magnitude normalization and proportional-integral controller, which estimates amplitude, phase, frequency and rate of change of frequency. The experimental results obtained by a test platform show that steady-state criteria are met.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"16 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73039664","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/COBEP/SPEC44138.2019.9065847
Dênis de Castro Pereira, Rúbio Campos Marques, P. S. Almeida, G. M. Soares, F. L. Tofoli, P. L. Tavares, Henrique Antônio Carvalho Braga
This work lies on the active cooling and thermal evaluation applied to an extra-high current (up to 12 A) chip-on-board (COB) light-emitting diode (LED). Simulations are performed employing computational fluid dynamics (CFD) so that the main thermal parameters can be obtained as close as possible to real results. Aiming at a thorough analysis of heat dissipation at very high current levels in floodlighting applications, a finite element analysis is carried out in order to establish a comparative approach concerning the convected air flow through a volume-reduced fin-heatsink. The simulated results show that the lighting system can be significantly improved by employing such active cooling technique for the device’s power rated condition (i.e., 350 W). For this operating point, the manufacturer’s heatsink physical volume could be decreased by 87% when applying the active cooling system with convected air flux, while also ensuring a safe thermal operation under maximum junction temperature of 120 °C.
{"title":"Active Cooling and Thermal Simulation Applied to an Extra-High Current COB LED","authors":"Dênis de Castro Pereira, Rúbio Campos Marques, P. S. Almeida, G. M. Soares, F. L. Tofoli, P. L. Tavares, Henrique Antônio Carvalho Braga","doi":"10.1109/COBEP/SPEC44138.2019.9065847","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065847","url":null,"abstract":"This work lies on the active cooling and thermal evaluation applied to an extra-high current (up to 12 A) chip-on-board (COB) light-emitting diode (LED). Simulations are performed employing computational fluid dynamics (CFD) so that the main thermal parameters can be obtained as close as possible to real results. Aiming at a thorough analysis of heat dissipation at very high current levels in floodlighting applications, a finite element analysis is carried out in order to establish a comparative approach concerning the convected air flow through a volume-reduced fin-heatsink. The simulated results show that the lighting system can be significantly improved by employing such active cooling technique for the device’s power rated condition (i.e., 350 W). For this operating point, the manufacturer’s heatsink physical volume could be decreased by 87% when applying the active cooling system with convected air flux, while also ensuring a safe thermal operation under maximum junction temperature of 120 °C.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"13 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73418279","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/COBEP/SPEC44138.2019.9065423
Rafael H. Eckstein, T. Lazzarin, G. Waltrich
It is no exaggeration to consider electric vehicles a reality in our current society. Comparing to combustion vehicles they have better efficiency and monetary profitability by distance traveled. However, the necessary infrastructure for the proper functioning of EVs, as batteries, individual chargers, charge stations, etc., are still precarious in several places. This paper introduces a new interleaved model for a low voltage battery pack charger for neighborhood electric vehicles (NEV). The system has two power stages, a SEPIC PFC rectifier and a DC-DC Buck converter, which process 1.5 kW per cell a total of 4.5 kW. The proposed system is adequate to lower power single-phase systems, which the battery pack voltage is lower than the grid.
{"title":"Two-Stage SEPIC-Buck Topology for Neighborhood Electric Vehicle Charger","authors":"Rafael H. Eckstein, T. Lazzarin, G. Waltrich","doi":"10.1109/COBEP/SPEC44138.2019.9065423","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065423","url":null,"abstract":"It is no exaggeration to consider electric vehicles a reality in our current society. Comparing to combustion vehicles they have better efficiency and monetary profitability by distance traveled. However, the necessary infrastructure for the proper functioning of EVs, as batteries, individual chargers, charge stations, etc., are still precarious in several places. This paper introduces a new interleaved model for a low voltage battery pack charger for neighborhood electric vehicles (NEV). The system has two power stages, a SEPIC PFC rectifier and a DC-DC Buck converter, which process 1.5 kW per cell a total of 4.5 kW. The proposed system is adequate to lower power single-phase systems, which the battery pack voltage is lower than the grid.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"104 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76118519","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/COBEP/SPEC44138.2019.9065493
I. F. Carvalho, M. Corrêa
Due to the increasing proportion of photovoltaic production in the electric generation mix, it is important to know the capacity of photovoltaic generation to estimate the efficiency of the solar power plant in any condition and thus to predict the point where the maximum power is converted. The process of converting solar energy into electrical energy is directly influenced by the level of irradiance and temperature of the photovoltaic module. In this way, equipment and tools that enable the acquisition of such data contribute directly to the knowledge of the efficiency of the photovoltaic system. While the acquisition of temperature values in photovoltaic panels is easy to implement, the same does not occur for irradiance values, where the costs of the sensors and their calibration are some of the problems faced. With the objective of exploring and comparing irradiance estimation techniques, the present work presents four solar radiation estimation algorithms, based on PV panel datasheet.
{"title":"Techniques of Solar Irradiance Estimation from Datasheet Information of Photovoltaic Panels","authors":"I. F. Carvalho, M. Corrêa","doi":"10.1109/COBEP/SPEC44138.2019.9065493","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065493","url":null,"abstract":"Due to the increasing proportion of photovoltaic production in the electric generation mix, it is important to know the capacity of photovoltaic generation to estimate the efficiency of the solar power plant in any condition and thus to predict the point where the maximum power is converted. The process of converting solar energy into electrical energy is directly influenced by the level of irradiance and temperature of the photovoltaic module. In this way, equipment and tools that enable the acquisition of such data contribute directly to the knowledge of the efficiency of the photovoltaic system. While the acquisition of temperature values in photovoltaic panels is easy to implement, the same does not occur for irradiance values, where the costs of the sensors and their calibration are some of the problems faced. With the objective of exploring and comparing irradiance estimation techniques, the present work presents four solar radiation estimation algorithms, based on PV panel datasheet.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"129 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76711068","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/COBEP/SPEC44138.2019.9065733
Eliabe Duarte Queiroz, J. Antenor Pomilio
A SRF-PLL model considering voltage influences is used to develop a state-space model of a current source converter operating on droop mode. The linear and non-linear models are simulated with two different frequency estimations. Due to the frequency estimation, an instability arises in the non-linear simulation and it is verified in the linear model. Comparisons are made between the linear and non-linear models.
{"title":"SRF-PLL Influence on the Stability of a Current Source Converter in Droop Mode","authors":"Eliabe Duarte Queiroz, J. Antenor Pomilio","doi":"10.1109/COBEP/SPEC44138.2019.9065733","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065733","url":null,"abstract":"A SRF-PLL model considering voltage influences is used to develop a state-space model of a current source converter operating on droop mode. The linear and non-linear models are simulated with two different frequency estimations. Due to the frequency estimation, an instability arises in the non-linear simulation and it is verified in the linear model. Comparisons are made between the linear and non-linear models.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"101 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77417087","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/COBEP/SPEC44138.2019.9065674
Vitor C. S. Torres, Vinícius M. de Albuquerque, M. A. Rendón, P. S. Almeida, J. G. Oliveira, M. Rodrigues
This paper presents the development of a state-space-based modeling approach for an interleaved bidirectional DC-DC converter, which is part of an aircraft hybrid propulsion system. The proposed model is presented in order to obtain relationships of voltage and current control loops of two operational modes of this interleaved DC-DC converter: buck mode, which controls voltage and current during on-board battery pack charging; and boost mode, responsible for aircraft hybrid propulsion system DC bus regulation. Simulation results are used to validate the developed model as well as to evaluate control system performance.
{"title":"Interleaved Bidirectional DC-DC Converter for Application in Hybrid Propulsion System: Modeling and Control","authors":"Vitor C. S. Torres, Vinícius M. de Albuquerque, M. A. Rendón, P. S. Almeida, J. G. Oliveira, M. Rodrigues","doi":"10.1109/COBEP/SPEC44138.2019.9065674","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065674","url":null,"abstract":"This paper presents the development of a state-space-based modeling approach for an interleaved bidirectional DC-DC converter, which is part of an aircraft hybrid propulsion system. The proposed model is presented in order to obtain relationships of voltage and current control loops of two operational modes of this interleaved DC-DC converter: buck mode, which controls voltage and current during on-board battery pack charging; and boost mode, responsible for aircraft hybrid propulsion system DC bus regulation. Simulation results are used to validate the developed model as well as to evaluate control system performance.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"106 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76934815","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/COBEP/SPEC44138.2019.9065501
Lorena Lorraine Oliveira Albuquerque, Marcos Victor Dantas de Sá, Fellipe André Lucena de Oliveira, I. Soares de Freitas, R. Andersen
This paper proposes the mathematic model and the control of the current and voltage loops of the ZVS-PWM three-phase current-fed push-pull DC-DC converter. The converter has three ports, two bidirectional ports and one unidirectional port and can be used in various applications such as electric vehicles, battery charging system, fuel cell, isolated mini grids and micro grids. The proposed control is able to invert power flow by imposing main inductor current value and direction as well as maintaining voltage at a given port under load variations. The control structure for each case is presented, as well as the deduction of the main mathematical expressions. In order to validate the performance of the proposed control strategy, simulation results for a 500 W converter with 50V in port 1 and 200 V in port 3 and a switching frequency of 40 kHz are presented here.
{"title":"Dynamic Modeling and Control of a Three-Port ZVS-PWM Three-Phase Push Pull DC-DC Converter","authors":"Lorena Lorraine Oliveira Albuquerque, Marcos Victor Dantas de Sá, Fellipe André Lucena de Oliveira, I. Soares de Freitas, R. Andersen","doi":"10.1109/COBEP/SPEC44138.2019.9065501","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065501","url":null,"abstract":"This paper proposes the mathematic model and the control of the current and voltage loops of the ZVS-PWM three-phase current-fed push-pull DC-DC converter. The converter has three ports, two bidirectional ports and one unidirectional port and can be used in various applications such as electric vehicles, battery charging system, fuel cell, isolated mini grids and micro grids. The proposed control is able to invert power flow by imposing main inductor current value and direction as well as maintaining voltage at a given port under load variations. The control structure for each case is presented, as well as the deduction of the main mathematical expressions. In order to validate the performance of the proposed control strategy, simulation results for a 500 W converter with 50V in port 1 and 200 V in port 3 and a switching frequency of 40 kHz are presented here.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"29 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81980315","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/COBEP/SPEC44138.2019.9065739
T. Estrabis, Raymundo Cordero García, E. Batista, Cristiano Quevedo Andrea, Márcio Afonso Soleira Grassi
A resolver is an angular position sensor used in applications that demands robustness and reliability, such as electric vehicles. However, getting the angular position from resolver output signals is a difficult task, and many algorithms were proposed to achieve that task. This paper describes the application of model predictive control (MPC) to get the angular position from resolver signals. Synchronous demodulation is used to get the envelopes of the resolver outputs and get the estimation error. The structure of the conventional model predictive controller was modified to be used as an angle tracking observer (ATO). Simulations show the performance of the proposed approach. According to the bibliographic review of the authors, it is the first time that model predictive control is applied as an observer to get the angular position from resolver signals.
{"title":"Application of Model Predictive Control in a Resolver-to-Digital Converter","authors":"T. Estrabis, Raymundo Cordero García, E. Batista, Cristiano Quevedo Andrea, Márcio Afonso Soleira Grassi","doi":"10.1109/COBEP/SPEC44138.2019.9065739","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065739","url":null,"abstract":"A resolver is an angular position sensor used in applications that demands robustness and reliability, such as electric vehicles. However, getting the angular position from resolver output signals is a difficult task, and many algorithms were proposed to achieve that task. This paper describes the application of model predictive control (MPC) to get the angular position from resolver signals. Synchronous demodulation is used to get the envelopes of the resolver outputs and get the estimation error. The structure of the conventional model predictive controller was modified to be used as an angle tracking observer (ATO). Simulations show the performance of the proposed approach. According to the bibliographic review of the authors, it is the first time that model predictive control is applied as an observer to get the angular position from resolver signals.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"3 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82756606","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/COBEP/SPEC44138.2019.9065604
C. C. C. dos Santos, C. F. Moraes, J. D. da Costa, C. Stein, E. Carati, R. Cardoso
Aiming to generate the maximum power available in photovoltaic systems, maximum power point tracking (MPPT) algorithms are employed. However, with the increased penetration of photovoltaic systems in the grid, it is also necessary that these systems operate with limited power during voltage sags and overvoltage conditions. This paper presents a control method applied to a photovoltaic boost converter to provide a transition between the MPPT and limited power point tracking (LPPT) algorithms. This transition can help the photovoltaic inverter when is necessary to inject less energy to regulate the grid and interrupt the power injection during critical faults. The proposed control method was tested in a boost converter, using a power supply that emulates a photovoltaic module.
{"title":"Photovoltaic Boost Converter Control Operating in the MPPT and LPPT Modes","authors":"C. C. C. dos Santos, C. F. Moraes, J. D. da Costa, C. Stein, E. Carati, R. Cardoso","doi":"10.1109/COBEP/SPEC44138.2019.9065604","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065604","url":null,"abstract":"Aiming to generate the maximum power available in photovoltaic systems, maximum power point tracking (MPPT) algorithms are employed. However, with the increased penetration of photovoltaic systems in the grid, it is also necessary that these systems operate with limited power during voltage sags and overvoltage conditions. This paper presents a control method applied to a photovoltaic boost converter to provide a transition between the MPPT and limited power point tracking (LPPT) algorithms. This transition can help the photovoltaic inverter when is necessary to inject less energy to regulate the grid and interrupt the power injection during critical faults. The proposed control method was tested in a boost converter, using a power supply that emulates a photovoltaic module.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"9 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86540216","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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