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":null,"pages":null},"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/SPEC44138.2019.9065517
Paulo R. Cagnini, L. H. Meneghetti, Victor E. S. Barbosa, E. Carati, C. Stein, Z. Nadal, Jean M. S. Lafay, Jean Patric da Costa, R. Cardoso
This paper proposes the use of a topology of a positive-input boost converter and symmetrical positive and negative outputs for the DC-DC stage of a microinverter connected to the electrical network with a small number of semiconductor switches. To validate and prove the operation of the system, simulations were performed in the PSIM software. All controllers and frequency-locked-loop (FLL) are exposed in the discrete form to facilitate implementation in a digital signal processor. For the reliability and adherence of the simulations with real cases, real data of solar irradiance and temperature of panels were experimentally collected and used.
{"title":"Microinverter with reduced number of semiconductor switches","authors":"Paulo R. Cagnini, L. H. Meneghetti, Victor E. S. Barbosa, E. Carati, C. Stein, Z. Nadal, Jean M. S. Lafay, Jean Patric da Costa, R. Cardoso","doi":"10.1109/COBEP/SPEC44138.2019.9065517","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065517","url":null,"abstract":"This paper proposes the use of a topology of a positive-input boost converter and symmetrical positive and negative outputs for the DC-DC stage of a microinverter connected to the electrical network with a small number of semiconductor switches. To validate and prove the operation of the system, simulations were performed in the PSIM software. All controllers and frequency-locked-loop (FLL) are exposed in the discrete form to facilitate implementation in a digital signal processor. For the reliability and adherence of the simulations with real cases, real data of solar irradiance and temperature of panels were experimentally collected and used.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89014721","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/SPEC44138.2019.9065606
Marcos Roberto Oshiro, Ruben Barros Godoy, M. D. de Brito, L. Galotto
In this paper some anti-islanding detection methods are evaluated through MatLab/Simulink® models. The methods are embedded into the control system of a voltage source inverter that is used to inject power to the grid from a set of photovoltaic modules. Due to low efficiency of the passive methods in detection of islanding and to the high cost of implementing the remote methods, only the active methods will be evaluated. In that sense, this paper presents comparative analysis regarding Active Frequency Drift (AFD), Slip-Mode Frequency Shift (SMS) and Sandia Frequency Shift (SFS) methods. Commonly, the active methods are implemented combining the passive sub/overvoltage and sub/overfrequency protection methods. The simulations presented comply with the voltage and frequency limits established by IEEE Std 929-2000 and harmonic distortion established by IEEE Std 519-2014.
{"title":"Performance Analysis of Active Anti-islanding Techniques for Photovoltaic Application","authors":"Marcos Roberto Oshiro, Ruben Barros Godoy, M. D. de Brito, L. Galotto","doi":"10.1109/COBEP/SPEC44138.2019.9065606","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065606","url":null,"abstract":"In this paper some anti-islanding detection methods are evaluated through MatLab/Simulink® models. The methods are embedded into the control system of a voltage source inverter that is used to inject power to the grid from a set of photovoltaic modules. Due to low efficiency of the passive methods in detection of islanding and to the high cost of implementing the remote methods, only the active methods will be evaluated. In that sense, this paper presents comparative analysis regarding Active Frequency Drift (AFD), Slip-Mode Frequency Shift (SMS) and Sandia Frequency Shift (SFS) methods. Commonly, the active methods are implemented combining the passive sub/overvoltage and sub/overfrequency protection methods. The simulations presented comply with the voltage and frequency limits established by IEEE Std 929-2000 and harmonic distortion established by IEEE Std 519-2014.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86116306","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/SPEC44138.2019.9065833
F. Imai, Y. D. de Novaes
In this work is presented a bipolar Marx Generator (MG) to create pulsed electric fields in electroporation, technique consisting of creating pores on plasma membranes in different medical treatments. The Marx Generator is a voltage multiplier that charges capacitors in parallel and discharges them in series on the output. A new position for the power switches is proposed in order to allow a better control of capacitor individual usage. The main electrical parameters are mentioned and explained how they affect the design of the electroporator. At the end, experimetal tests are performed using vegetable samples as load, to analyze the current response and visual effects of the pulses application.
{"title":"Design and Assembly of a Bipolar Marx Generator Based on Full-Bridge Topology Applied to Electroporation","authors":"F. Imai, Y. D. de Novaes","doi":"10.1109/COBEP/SPEC44138.2019.9065833","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065833","url":null,"abstract":"In this work is presented a bipolar Marx Generator (MG) to create pulsed electric fields in electroporation, technique consisting of creating pores on plasma membranes in different medical treatments. The Marx Generator is a voltage multiplier that charges capacitors in parallel and discharges them in series on the output. A new position for the power switches is proposed in order to allow a better control of capacitor individual usage. The main electrical parameters are mentioned and explained how they affect the design of the electroporator. At the end, experimetal tests are performed using vegetable samples as load, to analyze the current response and visual effects of the pulses application.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85040365","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/SPEC44138.2019.9065476
Murilo Brunel da Rosa, Menaouar Berrehil El Kattel, Robson Mayer, Sérgio Vidal Garcia Oliveira
In this paper, the theoretical analysis and the experimental results of the bidirectional coupled inductor DC-DC converter are presented. The proposed topology is relatively feasible for low-input-voltage applications for interfacing energy storage elements, such as batteries, and ultracapacitors with the high voltage DC bus in hybrid electric vehicles and electric vehicles. The operation principles, the dc voltage gain, the filters design and the voltage and current stresses are discussed. In order to validate the theoretical study and to prove the converter performance, some experimental results are obtained from a laboratory prototype of 600 W.
{"title":"Experimental Results of a Bidirectional Coupled Inductor DC-DC Converter","authors":"Murilo Brunel da Rosa, Menaouar Berrehil El Kattel, Robson Mayer, Sérgio Vidal Garcia Oliveira","doi":"10.1109/COBEP/SPEC44138.2019.9065476","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065476","url":null,"abstract":"In this paper, the theoretical analysis and the experimental results of the bidirectional coupled inductor DC-DC converter are presented. The proposed topology is relatively feasible for low-input-voltage applications for interfacing energy storage elements, such as batteries, and ultracapacitors with the high voltage DC bus in hybrid electric vehicles and electric vehicles. The operation principles, the dc voltage gain, the filters design and the voltage and current stresses are discussed. In order to validate the theoretical study and to prove the converter performance, some experimental results are obtained from a laboratory prototype of 600 W.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90760280","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/SPEC44138.2019.9065386
Marcos Paulo Brito Gomes, Marina Hassen de Souza, G. V. Ramos, A. Luiz, M. M. Stopa
This paper presents a study related to an electric drive composed by an induction machine fed by a NPC (neutral point clamped) frequency inverter, extending also to ANPC (active neutral point clamped) topologies, and IGBTs commanded by a SHE-PWM (selective harmonic elimination pulse width modulation) logic pattern. This work also addresses a concern related to the number of dv/dts reproduced in a fundamental period of a waveform, which is related to the semiconductors switching frequency. These dv/dts cause degradations to electric motors and its mitigation contributes minimizing problems on windings, insulations and bearings erosion. A SHE-PWM pattern with very low switching frequency is presented with simulations and experimental results mitigating the 5th and 7th harmonics for the entire drive voltage index modulation range. These harmonics have high amplitude and low frequency, causing high drive losses, and can be reduced by a modulation with semiconductors switching in a frequency equivalent to 360Hz, with high quality and symmetrical voltage and currents waveforms. SHE-PWM was compared with POD-PWM at the same switching rate, through simulation and harmonic content investigated by the DTFT (Discrete Time Fourier Transform).
{"title":"Application of a SHE-PWM modulation for a low switching frequency motor drive with harmonic investigation using the DTFT","authors":"Marcos Paulo Brito Gomes, Marina Hassen de Souza, G. V. Ramos, A. Luiz, M. M. Stopa","doi":"10.1109/COBEP/SPEC44138.2019.9065386","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065386","url":null,"abstract":"This paper presents a study related to an electric drive composed by an induction machine fed by a NPC (neutral point clamped) frequency inverter, extending also to ANPC (active neutral point clamped) topologies, and IGBTs commanded by a SHE-PWM (selective harmonic elimination pulse width modulation) logic pattern. This work also addresses a concern related to the number of dv/dts reproduced in a fundamental period of a waveform, which is related to the semiconductors switching frequency. These dv/dts cause degradations to electric motors and its mitigation contributes minimizing problems on windings, insulations and bearings erosion. A SHE-PWM pattern with very low switching frequency is presented with simulations and experimental results mitigating the 5th and 7th harmonics for the entire drive voltage index modulation range. These harmonics have high amplitude and low frequency, causing high drive losses, and can be reduced by a modulation with semiconductors switching in a frequency equivalent to 360Hz, with high quality and symmetrical voltage and currents waveforms. SHE-PWM was compared with POD-PWM at the same switching rate, through simulation and harmonic content investigated by the DTFT (Discrete Time Fourier Transform).","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87279040","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/SPEC44138.2019.9065351
Antonio Venâncio de M. Lacerda Filho, A. E. L. da Costa, E. D. da Silva, Ronnan de B. Cardoso, D. Fernandes
This paper reports a new five-level pulse-width modulation (PWM) that includes a flying capacitor supplied by a boost/flyback DC-DC converter that also provides the DC-bus voltage. There is a significant reduction in the number of power devices and capacitors required to implement a conventional five-level flying capacitor inverter. The topology is free from complex PWM control to regulate the capacitor voltage and is capable of operating under any power factor condition. Simulated and experimental results validate the converter principle.
{"title":"New Five-Level Flying Capacitor Inverter Fed by a Boost-Flyback DC-DC Voltage Source","authors":"Antonio Venâncio de M. Lacerda Filho, A. E. L. da Costa, E. D. da Silva, Ronnan de B. Cardoso, D. Fernandes","doi":"10.1109/COBEP/SPEC44138.2019.9065351","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065351","url":null,"abstract":"This paper reports a new five-level pulse-width modulation (PWM) that includes a flying capacitor supplied by a boost/flyback DC-DC converter that also provides the DC-bus voltage. There is a significant reduction in the number of power devices and capacitors required to implement a conventional five-level flying capacitor inverter. The topology is free from complex PWM control to regulate the capacitor voltage and is capable of operating under any power factor condition. Simulated and experimental results validate the converter principle.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87507181","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/SPEC44138.2019.9065635
Jean M. L. Fonseca, Francisco Kleber A. Lima, C. Branco, R. G. Araújo
This paper proposes the expansion of two phase-locked loop structures to detect positive and negative sequence components. The first structure is a positive sequence detector only and the second one is a modification of the first one where an adaptive filter is added to increase filtering capability in scenarios with interharmonic distortion. Both proposed structures were implemented in the hardware-in-the-loop (HIL) dSPACE 1103 platform together with two well known structures, the DSOGI-FLL and the DDSRF-PLL. Steady-state and dynamic response of each structure were analyzed in scenarios with either harmonic distortion only or harmonic and interharmonic distortion. Results showed that the proposed structures are highly accurate, specifically under harmonic distortion, however the structure with adaptive filter is slower. In addition, results showed that the structures are at least as precise and fast as the DSOGI-FLL and DDSRF-PLL. Lastly, under interharmonic distortion, it is also found that the PLL with adaptive filter has an overall better performance.
{"title":"A Novel Phase-Locked Loop with Positive and Negative Sequence Detection Capability","authors":"Jean M. L. Fonseca, Francisco Kleber A. Lima, C. Branco, R. G. Araújo","doi":"10.1109/COBEP/SPEC44138.2019.9065635","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065635","url":null,"abstract":"This paper proposes the expansion of two phase-locked loop structures to detect positive and negative sequence components. The first structure is a positive sequence detector only and the second one is a modification of the first one where an adaptive filter is added to increase filtering capability in scenarios with interharmonic distortion. Both proposed structures were implemented in the hardware-in-the-loop (HIL) dSPACE 1103 platform together with two well known structures, the DSOGI-FLL and the DDSRF-PLL. Steady-state and dynamic response of each structure were analyzed in scenarios with either harmonic distortion only or harmonic and interharmonic distortion. Results showed that the proposed structures are highly accurate, specifically under harmonic distortion, however the structure with adaptive filter is slower. In addition, results showed that the structures are at least as precise and fast as the DSOGI-FLL and DDSRF-PLL. Lastly, under interharmonic distortion, it is also found that the PLL with adaptive filter has an overall better performance.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84029575","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/SPEC44138.2019.9065861
Mateo D. Roig G., C. G. da S. Moraes, T. Lazzarin
This article presents an analysis and design of an AC-DC Boost single-phase converter operating in discontinuous conduction mode (DCM) with output voltage regulation and power factor correction (PFC). The topology dispenses the rectifier bridge reducing the conduction losses and, however, it is already known in the literature, there is no previously steady-state modeling presented for this operation mode. Furthermore, the article presents a comparison between the converter with the other two common used topologies for the same kind of application. All results were validated with a 500 W prototype, with a universal input 100 – 220 VAC and 450 VDC voltage output. The results presented nearby 96% of efficiency.
{"title":"Steady-State Analysis of a Single-phase Modified Bridgeless Boost Rectifier in DCM","authors":"Mateo D. Roig G., C. G. da S. Moraes, T. Lazzarin","doi":"10.1109/COBEP/SPEC44138.2019.9065861","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065861","url":null,"abstract":"This article presents an analysis and design of an AC-DC Boost single-phase converter operating in discontinuous conduction mode (DCM) with output voltage regulation and power factor correction (PFC). The topology dispenses the rectifier bridge reducing the conduction losses and, however, it is already known in the literature, there is no previously steady-state modeling presented for this operation mode. Furthermore, the article presents a comparison between the converter with the other two common used topologies for the same kind of application. All results were validated with a 500 W prototype, with a universal input 100 – 220 VAC and 450 VDC voltage output. The results presented nearby 96% of efficiency.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88389922","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":null,"pages":null},"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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