Pub Date : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960278
M. Taherzadeh, S. Carriere, F. Betin, M. Joorabian, R. Kianinezhad, G. Capolino
This study presents field oriented control of a squirrel cage six-phase induction generator (SC6PIG) when a phase fault is detected in order to minimize output power oscillations during phase opening. An unbalanced structure of squirrel cage six-phase induction machine (SC6PIM) has been modeled to analyze healthy and faulty conditions of the machine. According to the unbalanced structure of the machine, a suitable controller is defined in phase missing condition to minimize power oscillations. After fault detection by using a dedicated system, the controller used in healthy condition is switched to a new one regarding to the fault situation. For each controller, appropriate initial conditions are chosen to minimize the transient behavior of switching process between healthy and faulty controllers. The whole proposed system has been implemented on an experimental set up including of a six-phase induction generator coupled with a permanent magnet direct current (dc) motor. Experimental results prove the feasibility and show the improvement of power quality when the controller is modified in phase missing conditions. The experimental results are presented for one phase missing and they can also be obtained for two or three phases missing conditions.
{"title":"Online controller modifying of a six-phase induction generator in phase opening occurrences","authors":"M. Taherzadeh, S. Carriere, F. Betin, M. Joorabian, R. Kianinezhad, G. Capolino","doi":"10.1109/ICELMACH.2014.6960278","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960278","url":null,"abstract":"This study presents field oriented control of a squirrel cage six-phase induction generator (SC6PIG) when a phase fault is detected in order to minimize output power oscillations during phase opening. An unbalanced structure of squirrel cage six-phase induction machine (SC6PIM) has been modeled to analyze healthy and faulty conditions of the machine. According to the unbalanced structure of the machine, a suitable controller is defined in phase missing condition to minimize power oscillations. After fault detection by using a dedicated system, the controller used in healthy condition is switched to a new one regarding to the fault situation. For each controller, appropriate initial conditions are chosen to minimize the transient behavior of switching process between healthy and faulty controllers. The whole proposed system has been implemented on an experimental set up including of a six-phase induction generator coupled with a permanent magnet direct current (dc) motor. Experimental results prove the feasibility and show the improvement of power quality when the controller is modified in phase missing conditions. The experimental results are presented for one phase missing and they can also be obtained for two or three phases missing conditions.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122919335","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960531
J. Estima, A. M. Marques Cardoso
The aim of this paper is to study the influence of the drive train topology on the temperature of the different components in permanent magnet synchronous motor (PMSM) drives applied to electric/hybrid vehicles. The temperature is a critical parameter because it is directly related to the lifetime and reliability of a device. This is particular important for PMSMs since it also influences the magnetic flux produced by the permanent magnets. Thus, in this paper two different drive train topologies applied to electric/hybrid vehicles are evaluated. The first one comprises a battery pack that directly supplies the inverter, and a PMSM. In the second topology, a step-up bidirectional dc-dc converter is connected between the batteries and the inverter dc supply. A variable voltage control is also applied in this topology to control the inverter supplying voltage. A detailed temperature analysis is presented in the format of three-dimension maps that allow to compare both topologies.
{"title":"Thermal evaluation of different drive train topologies for electric/hybrid vehicles","authors":"J. Estima, A. M. Marques Cardoso","doi":"10.1109/ICELMACH.2014.6960531","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960531","url":null,"abstract":"The aim of this paper is to study the influence of the drive train topology on the temperature of the different components in permanent magnet synchronous motor (PMSM) drives applied to electric/hybrid vehicles. The temperature is a critical parameter because it is directly related to the lifetime and reliability of a device. This is particular important for PMSMs since it also influences the magnetic flux produced by the permanent magnets. Thus, in this paper two different drive train topologies applied to electric/hybrid vehicles are evaluated. The first one comprises a battery pack that directly supplies the inverter, and a PMSM. In the second topology, a step-up bidirectional dc-dc converter is connected between the batteries and the inverter dc supply. A variable voltage control is also applied in this topology to control the inverter supplying voltage. A detailed temperature analysis is presented in the format of three-dimension maps that allow to compare both topologies.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115762296","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960246
F. Schuller, N. Parspour, Lei Chen
This paper outlines a position control system for a two phase linear permanent magnet excited transverse flux machine. A force ripple minimization technique is implemented by an inverse force-current look-up table and a subordinate current controller. The superordinate speed and position control enables positioning tasks. The control system is implemented on a rapid prototyping system and is tested on a prototype of a linear transverse flux machine. The aim is implementing a simple control structure, respecting the machine's electro-magnetic-mechanical behavior at the same time.
{"title":"Position control of a linear transverse flux machine with subordinate current control","authors":"F. Schuller, N. Parspour, Lei Chen","doi":"10.1109/ICELMACH.2014.6960246","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960246","url":null,"abstract":"This paper outlines a position control system for a two phase linear permanent magnet excited transverse flux machine. A force ripple minimization technique is implemented by an inverse force-current look-up table and a subordinate current controller. The superordinate speed and position control enables positioning tasks. The control system is implemented on a rapid prototyping system and is tested on a prototype of a linear transverse flux machine. The aim is implementing a simple control structure, respecting the machine's electro-magnetic-mechanical behavior at the same time.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122193367","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960538
D. Cozonac, J. Lecointe, S. Duchesne, G. Vélu
The goal of this paper is to describe the materials and building technique to design a high-temperature induction machine which temperature winding is about 500°C. First, the candidate materials are identified and because of the constraints imposed by these materials, a special geometry is proposed. The authors show that inorganic insulation has to be preferred for the conductors and the slot insulation. Tests are done to select the materials by measuring the turn to turn voltage, insulation resistances or the parallel capacities. It is shown that Grain Oriented (GO) Fe-Si magnetic steel sheets can be used for high temperature because of their insulation and their magnetic properties. The authors describe a technique using shifted GO steel sheets and they characterize up to 500°C. A particular geometry of the machine is described as well as the method to assemble the different parts of the machine.
{"title":"Materials characterization and geometry of a high temperature induction machine","authors":"D. Cozonac, J. Lecointe, S. Duchesne, G. Vélu","doi":"10.1109/ICELMACH.2014.6960538","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960538","url":null,"abstract":"The goal of this paper is to describe the materials and building technique to design a high-temperature induction machine which temperature winding is about 500°C. First, the candidate materials are identified and because of the constraints imposed by these materials, a special geometry is proposed. The authors show that inorganic insulation has to be preferred for the conductors and the slot insulation. Tests are done to select the materials by measuring the turn to turn voltage, insulation resistances or the parallel capacities. It is shown that Grain Oriented (GO) Fe-Si magnetic steel sheets can be used for high temperature because of their insulation and their magnetic properties. The authors describe a technique using shifted GO steel sheets and they characterize up to 500°C. A particular geometry of the machine is described as well as the method to assemble the different parts of the machine.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115853014","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960436
Andrew S. Babel, E. Strangas
A comprehensive diagnostic and prognostic method is introduced for assessing the condition of stator winding insulation and predicting its failure time. A diagnostic method is developed by building an analytical model of the stator winding. Degradation is simulated by altering the permittivity and conductivity of the insulation in a finite element model simulation and changing the analytical model accordingly. The diagnostic method is performed with an oscilloscope and other common hardware. A prognostic method is introduced which is used to predict the remaining useful life of the insulation based on fitting insulation current measurements to an exponential decay model. The diagnostic method is verified with the analytical model for multiple levels of degradation and experimentally for the healthy case. The prognostic method is verified with simulated degradation data.
{"title":"Condition-based monitoring and prognostic health management of electric machine stator winding insulation","authors":"Andrew S. Babel, E. Strangas","doi":"10.1109/ICELMACH.2014.6960436","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960436","url":null,"abstract":"A comprehensive diagnostic and prognostic method is introduced for assessing the condition of stator winding insulation and predicting its failure time. A diagnostic method is developed by building an analytical model of the stator winding. Degradation is simulated by altering the permittivity and conductivity of the insulation in a finite element model simulation and changing the analytical model accordingly. The diagnostic method is performed with an oscilloscope and other common hardware. A prognostic method is introduced which is used to predict the remaining useful life of the insulation based on fitting insulation current measurements to an exponential decay model. The diagnostic method is verified with the analytical model for multiple levels of degradation and experimentally for the healthy case. The prognostic method is verified with simulated degradation data.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132091528","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960384
M. Mohr, O. Bíró, F. Diwoky
This paper presents a finite element based circuit model approach for a permanent magnet synchronous machine considering rotor eccentricity effects. The presented model is well suited for multi body dynamics simulations, because it combines the coverage of saturation, slotting and eccentricity effects that is typically known from finite element models with a very low simulation cost. The focus of this work is on the validation of the proposed model. For this purpose several comparisons between the proposed model and transient finite element simulations with motion have been carried out.
{"title":"Consideration of rotor eccentricity effects in a multi body dynamics simulation using a finite element based circuit model approach","authors":"M. Mohr, O. Bíró, F. Diwoky","doi":"10.1109/ICELMACH.2014.6960384","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960384","url":null,"abstract":"This paper presents a finite element based circuit model approach for a permanent magnet synchronous machine considering rotor eccentricity effects. The presented model is well suited for multi body dynamics simulations, because it combines the coverage of saturation, slotting and eccentricity effects that is typically known from finite element models with a very low simulation cost. The focus of this work is on the validation of the proposed model. For this purpose several comparisons between the proposed model and transient finite element simulations with motion have been carried out.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134640186","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960365
K. Ishikawa, W. Kitagawa, T. Takeshita
Recently, one of the problems is high efficiency for the electromagnetic machinery like a motor. This paper presents a new method of shape optimization. The target is flux barriers in the interior permanent magnetic synchronous motor (IPMSM) which is adopted as the benchmark model in IEE of Japan. Authors use the polygon model method with genetic programming (GP) by the two-dimensional finite element method (2D-FEM). The purpose is the investigation of shape design of flux barriers to improve the electromagnetic characteristics. In a conventional method as a size optimization, its design parameters are limited in most cases. However, the proposed method is the shape optimization by the tree structure. This method has more freedom for design parameters because the tree structure is possible to express every shape design.
{"title":"Shape optimization of flux barriers in IPMSM by using polygon model method with GP","authors":"K. Ishikawa, W. Kitagawa, T. Takeshita","doi":"10.1109/ICELMACH.2014.6960365","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960365","url":null,"abstract":"Recently, one of the problems is high efficiency for the electromagnetic machinery like a motor. This paper presents a new method of shape optimization. The target is flux barriers in the interior permanent magnetic synchronous motor (IPMSM) which is adopted as the benchmark model in IEE of Japan. Authors use the polygon model method with genetic programming (GP) by the two-dimensional finite element method (2D-FEM). The purpose is the investigation of shape design of flux barriers to improve the electromagnetic characteristics. In a conventional method as a size optimization, its design parameters are limited in most cases. However, the proposed method is the shape optimization by the tree structure. This method has more freedom for design parameters because the tree structure is possible to express every shape design.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122484873","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960543
M. Novak, J. Novak, M. Schmirler
This paper presents the theoretical background and experimental results obtained during the development of a small combined heat and power unit. The unit's final output power when the development is finished should be 3kW of electrical power. The unit was built with an automotive turbocharger acting as a turbine and a high-speed permanent magnet synchronous machine. The achieved parameters so far are 550 W of DC power for 11 000 RPM. The power was converted to AC with a commercial active-front end unit into the 3×400 V, 50 Hz AC power network. Due to mechanical constrains the generator was running only with about ¼ of the final RPM (42000 RPM) and with about ½ of the nominal current (11 A); the 3 kW goal is achievable.
{"title":"Combined-heat and power generator with high-speed permanent magnet synchronous machine","authors":"M. Novak, J. Novak, M. Schmirler","doi":"10.1109/ICELMACH.2014.6960543","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960543","url":null,"abstract":"This paper presents the theoretical background and experimental results obtained during the development of a small combined heat and power unit. The unit's final output power when the development is finished should be 3kW of electrical power. The unit was built with an automotive turbocharger acting as a turbine and a high-speed permanent magnet synchronous machine. The achieved parameters so far are 550 W of DC power for 11 000 RPM. The power was converted to AC with a commercial active-front end unit into the 3×400 V, 50 Hz AC power network. Due to mechanical constrains the generator was running only with about ¼ of the final RPM (42000 RPM) and with about ½ of the nominal current (11 A); the 3 kW goal is achievable.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117218647","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960302
C. Schumann, Tobias Muller, E. Stein, M. Pacas
In the following paper, an analytical approach for the calculation of the the induced emf in windings of electrical machines is provided. This method uses the complex Fourier series that describe the stator winding function and the magnetic flux density distribution in the air gap that is caused by the rotor permanent magnets. By using a special case of the Parseval's theorem, the induced emf can be computed in an easy and straight-forward way. The practical implementation of the calculation scheme only uses sums of the product of the Fourier coefficients and therefore the computation is very fast. The proposed procedure is used for calculating the induced emf in a machine with two different PM rotors. One rotor uses a symmetrical magnet distribution, the other one uses an asymmetrical magnet distribution. The calculation delivers two different shapes of the induced voltage in the identical stator winding system. The air gap flux density is approximated in a simple way and expressed by an exponential function term. The analytically calculated results are compared with the results of a transient FEM simulation and, in case of the asymmetrical rotor with the measured emf on a sample machine validating in this way the proposed computation procedure.
{"title":"Analytical calculation of the induced EMF in PM-machines with arbitrary arranged surface mounted magnets using the winding function theory","authors":"C. Schumann, Tobias Muller, E. Stein, M. Pacas","doi":"10.1109/ICELMACH.2014.6960302","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960302","url":null,"abstract":"In the following paper, an analytical approach for the calculation of the the induced emf in windings of electrical machines is provided. This method uses the complex Fourier series that describe the stator winding function and the magnetic flux density distribution in the air gap that is caused by the rotor permanent magnets. By using a special case of the Parseval's theorem, the induced emf can be computed in an easy and straight-forward way. The practical implementation of the calculation scheme only uses sums of the product of the Fourier coefficients and therefore the computation is very fast. The proposed procedure is used for calculating the induced emf in a machine with two different PM rotors. One rotor uses a symmetrical magnet distribution, the other one uses an asymmetrical magnet distribution. The calculation delivers two different shapes of the induced voltage in the identical stator winding system. The air gap flux density is approximated in a simple way and expressed by an exponential function term. The analytically calculated results are compared with the results of a transient FEM simulation and, in case of the asymmetrical rotor with the measured emf on a sample machine validating in this way the proposed computation procedure.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116042253","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 : 2014-11-20DOI: 10.1109/ICELMACH.2014.6960472
Andrea Monni, I. Marongiu, A. Serpi, A. Damiano
The design of a Permanent Magnet Synchronous Generator (PMSG) suitable for off-shore direct drive wind energy conversion systems (WECSs) is presented in this paper. In particular, a twelve-phase PMSG, characterised by a surface mounted permanent magnet configuration and by outer rotor layout has been considered with the aim of improving torque quality, energy efficiency, power management, fault tolerance and reliability of WECS. For these purposes, fractional slot multiphase windings have been asymmetrical distributed in order to form four three-phase independent subsystems. Finally, a specific design procedure oriented to minimize cogging torque and to maximize magnetic decoupling of each three-phase subsystem has been developed. The analytical procedure and the corresponding results have been reported and validated by means of Finite Element Analysis (FEA), highlighting the worth and effectiveness of the proposed configuration.
{"title":"Design of a fractional slot multi-phase PMSG for a direct-drive wind turbine","authors":"Andrea Monni, I. Marongiu, A. Serpi, A. Damiano","doi":"10.1109/ICELMACH.2014.6960472","DOIUrl":"https://doi.org/10.1109/ICELMACH.2014.6960472","url":null,"abstract":"The design of a Permanent Magnet Synchronous Generator (PMSG) suitable for off-shore direct drive wind energy conversion systems (WECSs) is presented in this paper. In particular, a twelve-phase PMSG, characterised by a surface mounted permanent magnet configuration and by outer rotor layout has been considered with the aim of improving torque quality, energy efficiency, power management, fault tolerance and reliability of WECS. For these purposes, fractional slot multiphase windings have been asymmetrical distributed in order to form four three-phase independent subsystems. Finally, a specific design procedure oriented to minimize cogging torque and to maximize magnetic decoupling of each three-phase subsystem has been developed. The analytical procedure and the corresponding results have been reported and validated by means of Finite Element Analysis (FEA), highlighting the worth and effectiveness of the proposed configuration.","PeriodicalId":288960,"journal":{"name":"2014 International Conference on Electrical Machines (ICEM)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114790081","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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