Pub Date : 2016-09-01DOI: 10.1109/EPE.2016.7695654
R. Alsharif, M. Odavic
A photovoltaic generator (PVG) is usually connected to a DC micro-grid via a multi-stage-step-up power converter to improve system modularity, minimise shading effects and boost PVG voltage. Under varying operating conditions, the nonlinear characteristics of a PVG may affect performance of the entire PVG system. Further, if these issues are not properly taken into account at the design stage, significant changes in system dynamics may risk stability of the system. Therefore, it is important to understand interactions between a PVG and the rest of the system. A clear understanding of these interactions can help to set system design recommendations and guidelines. In particular, this paper explores the effects of a nonlinear PVG source interfacing a double-stage conventional boost converter connected to a DC bus. It addresses the impact of these effects on the design of both the power circuit and the control loops. Finally, this paper provides system design recommendations to ensure stability under varying operating conditions.
{"title":"Photovoltaic generators interfacing a DC micro-grid: Design considerations for a double-stage boost power converter system","authors":"R. Alsharif, M. Odavic","doi":"10.1109/EPE.2016.7695654","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695654","url":null,"abstract":"A photovoltaic generator (PVG) is usually connected to a DC micro-grid via a multi-stage-step-up power converter to improve system modularity, minimise shading effects and boost PVG voltage. Under varying operating conditions, the nonlinear characteristics of a PVG may affect performance of the entire PVG system. Further, if these issues are not properly taken into account at the design stage, significant changes in system dynamics may risk stability of the system. Therefore, it is important to understand interactions between a PVG and the rest of the system. A clear understanding of these interactions can help to set system design recommendations and guidelines. In particular, this paper explores the effects of a nonlinear PVG source interfacing a double-stage conventional boost converter connected to a DC bus. It addresses the impact of these effects on the design of both the power circuit and the control loops. Finally, this paper provides system design recommendations to ensure stability under varying operating conditions.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115419720","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695525
Mikel Mazuela, Alain Sanchez-Ruiz, I. Echeverria, Sebastian Telleria, Iñigo Atutxa
This paper proposes a systematic procedure in order to make an optimal comparison/selection of modulation techniques and output LCR filter components for adjustable speed drives. Useful indicators are identified, which may help the designer to a global solution, optimizing the modulation-filter selection. The procedure is applied into the design of a real 6.6 kV equipment.
{"title":"Modulation and LCR filter optimum design procedure for medium voltage adjustable speed drives","authors":"Mikel Mazuela, Alain Sanchez-Ruiz, I. Echeverria, Sebastian Telleria, Iñigo Atutxa","doi":"10.1109/EPE.2016.7695525","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695525","url":null,"abstract":"This paper proposes a systematic procedure in order to make an optimal comparison/selection of modulation techniques and output LCR filter components for adjustable speed drives. Useful indicators are identified, which may help the designer to a global solution, optimizing the modulation-filter selection. The procedure is applied into the design of a real 6.6 kV equipment.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123902759","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695416
A. Abramovitz, Ofir Korech, D. Shmilovitz
A simple and low cost quasi resonant LED driver is proposed. Prominent merits of the proposed topology are low line current distortion and reduced switch voltage stress. This paper presents the principle of operation of the proposed circuit, analysis of average power and switch voltage and current stress. Theoretical predictions are supported by simulation and experiment.
{"title":"Quasi resonant totem pole LED driver","authors":"A. Abramovitz, Ofir Korech, D. Shmilovitz","doi":"10.1109/EPE.2016.7695416","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695416","url":null,"abstract":"A simple and low cost quasi resonant LED driver is proposed. Prominent merits of the proposed topology are low line current distortion and reduced switch voltage stress. This paper presents the principle of operation of the proposed circuit, analysis of average power and switch voltage and current stress. Theoretical predictions are supported by simulation and experiment.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"210 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124581634","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695566
M. Jiménez Carrizosa, A. Arzande, M. Vasić, P. Alou, J. Vannier
This paper presents a new modulation for modular multilevel converters (MMC) based on a simple idea, which is very easy to implement. It consists of playing with the relative behaviour of each phase in order to obtain the desired AC voltage. This method also assures that the voltage capacitor in each sub-module remains constant. Moreover, this converter allows the operation of the system under unbalanced conditions, and it can be used intrinsically as a DC circuit-breaker (DC-CB) without the need for additional power electronics and control if full bridge sub-modules are used.
{"title":"A new control for modular multilevel converters and their use as DC circuit breaker","authors":"M. Jiménez Carrizosa, A. Arzande, M. Vasić, P. Alou, J. Vannier","doi":"10.1109/EPE.2016.7695566","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695566","url":null,"abstract":"This paper presents a new modulation for modular multilevel converters (MMC) based on a simple idea, which is very easy to implement. It consists of playing with the relative behaviour of each phase in order to obtain the desired AC voltage. This method also assures that the voltage capacitor in each sub-module remains constant. Moreover, this converter allows the operation of the system under unbalanced conditions, and it can be used intrinsically as a DC circuit-breaker (DC-CB) without the need for additional power electronics and control if full bridge sub-modules are used.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116945662","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695633
Nabais Lima Tiago, A. Rufer
An input-series/output-series converter dedicated to high power applications is presented. The converter is composed of plural MF transformers based on DC-DC sub-converters. The series connection allows reaching input-voltage levels in the range of several tens or hundreds of kV. The power level can be increased by modularity, even if the size of one MF transformer is generally limited by the size of the available magnetic cores. Each sub-converter has at its primary side a 3-Level Half-Bridge inverter that generates the MF intermediary voltage. The output circuit of each sub-converter is a simple diode rectifier. The series input circuit is completed by an active balancing circuit which allows the N-1 operation of the installed channels with unmodified input voltage conditions. The paper presents the new topology together with the adopted control structure. The performance of the proposed architecture and its possible mode of operation with one or more disabled sub-converters is verified with a small-scale demonstrator.
{"title":"Input-series and output-series high voltage converter with active balancing circuit for N-1 operation","authors":"Nabais Lima Tiago, A. Rufer","doi":"10.1109/EPE.2016.7695633","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695633","url":null,"abstract":"An input-series/output-series converter dedicated to high power applications is presented. The converter is composed of plural MF transformers based on DC-DC sub-converters. The series connection allows reaching input-voltage levels in the range of several tens or hundreds of kV. The power level can be increased by modularity, even if the size of one MF transformer is generally limited by the size of the available magnetic cores. Each sub-converter has at its primary side a 3-Level Half-Bridge inverter that generates the MF intermediary voltage. The output circuit of each sub-converter is a simple diode rectifier. The series input circuit is completed by an active balancing circuit which allows the N-1 operation of the installed channels with unmodified input voltage conditions. The paper presents the new topology together with the adopted control structure. The performance of the proposed architecture and its possible mode of operation with one or more disabled sub-converters is verified with a small-scale demonstrator.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116418683","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695648
R. Slatter, Matthias Brusius, H. Knoll
New control techniques for electric drives pose new problems for the manufacturers of current sensors. In particular the sensorless control of permanent magnet synchronous machines places new demands on the current sensors used to measure the motor phase currents. The latest control techniques to determine the rotor position from the inductive signature of the electric machine require best performance characteristics for phase current sensing in terms of dynamic range and bandwidth. Oversampling of the motor current allows a low noise calculation of the rate of change of current (di/dt), which improves the measurement resolution and allows smooth operation down to zero speed without negative side-effects, such as acoustic noise. The magnetoresistive (MR) effect offers a unique combination of high bandwidth, high resolution, miniaturization and robustness, and is particularly well-suited for the development of compact, fast and accurate current sensors. The power losses are significantly lower than for shunt resistors and the response time is almost an order of magnitude faster than for hall-effect based current sensors. Furthermore, MR-based current sensors have an extremely high bandwidth, in the range of several MHz, which allows the full exploitation of new wide bandgap power electronic technologies, such as Silicon Carbide switches and diodes.
{"title":"Development of high bandwidth current sensors based on the magnetoresistive effect","authors":"R. Slatter, Matthias Brusius, H. Knoll","doi":"10.1109/EPE.2016.7695648","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695648","url":null,"abstract":"New control techniques for electric drives pose new problems for the manufacturers of current sensors. In particular the sensorless control of permanent magnet synchronous machines places new demands on the current sensors used to measure the motor phase currents. The latest control techniques to determine the rotor position from the inductive signature of the electric machine require best performance characteristics for phase current sensing in terms of dynamic range and bandwidth. Oversampling of the motor current allows a low noise calculation of the rate of change of current (di/dt), which improves the measurement resolution and allows smooth operation down to zero speed without negative side-effects, such as acoustic noise. The magnetoresistive (MR) effect offers a unique combination of high bandwidth, high resolution, miniaturization and robustness, and is particularly well-suited for the development of compact, fast and accurate current sensors. The power losses are significantly lower than for shunt resistors and the response time is almost an order of magnitude faster than for hall-effect based current sensors. Furthermore, MR-based current sensors have an extremely high bandwidth, in the range of several MHz, which allows the full exploitation of new wide bandgap power electronic technologies, such as Silicon Carbide switches and diodes.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"7 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123662363","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695661
V. Šmídl, V. Mácha, Š. Janouš, Z. Peroutka
Performance of the PMSM numerical predictive control on very long horizon is studied in simulation. It is shown that the trajectories of optimally controlled system follow the well known trajectories of maximum torque per ampere and maximum torque per volt. Significant difference from these trajectories is observed only at rapid request for maximum current. We compare the numerical solution with analytically obtained solution of minimum time current control. We show that available minimum time current control algorithm do not match the observed trajectory. An idea how to achieve the same behavior using only one step ahead prediction is proposed. The time optimal current control is approximated using ad-hoc arguments. The challenge for future research is to design better minimum time current control strategy.
{"title":"Analysis of cost functions and setpoints for predictive speed control of PMSM drives","authors":"V. Šmídl, V. Mácha, Š. Janouš, Z. Peroutka","doi":"10.1109/EPE.2016.7695661","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695661","url":null,"abstract":"Performance of the PMSM numerical predictive control on very long horizon is studied in simulation. It is shown that the trajectories of optimally controlled system follow the well known trajectories of maximum torque per ampere and maximum torque per volt. Significant difference from these trajectories is observed only at rapid request for maximum current. We compare the numerical solution with analytically obtained solution of minimum time current control. We show that available minimum time current control algorithm do not match the observed trajectory. An idea how to achieve the same behavior using only one step ahead prediction is proposed. The time optimal current control is approximated using ad-hoc arguments. The challenge for future research is to design better minimum time current control strategy.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121955264","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695444
J. Itoh, T. Sakuraba, Hoai Nam dLe, K. Kusaka
This paper discusses how to achieve high power density with high efficiency for a single-phase inverter with an active power decoupling circuit. In conventional PV inverters, bulky electrolytic capacitors are connected to DC-link in order to absorb power pulsation with twice the grid frequency. On the other hand, in the active power decoupling circuit, the small capacitor can be used. However, the additional inductors and switching devices are necessary. Thus, the power density of the active power decoupling circuit is reduced. In this paper, the Pareto optimization of power density and efficiency is used to clarify the maximum power density points of the power decoupling circuits. As a result, the maximum power density of the conventional boost type active buffer, which connects a boost chopper to DC-link, is 90% of that of electrolytic capacitor topology. In addition, this paper proposes a DC-DC converter with the power decoupling capability in order to achieve higher power density than that of the passive topology. The proposed circuit, which requires no additional inductor for the power decoupling circuit, uses discontinuous current mode (DCM) for the power decoupling capability. As a result, the maximum power density is obtained to 1.1 times higher than that of passive topology. However, the total loss of switching devices is 1.5 times higher. Thus, in order to surpass the efficiency of the passive topology by the active power decoupling, the switching device is required to reduce the total loss by 35% compared to the present products.
{"title":"Requirements for circuit components of single-phase inverter applied with power decoupling capability toward high power density","authors":"J. Itoh, T. Sakuraba, Hoai Nam dLe, K. Kusaka","doi":"10.1109/EPE.2016.7695444","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695444","url":null,"abstract":"This paper discusses how to achieve high power density with high efficiency for a single-phase inverter with an active power decoupling circuit. In conventional PV inverters, bulky electrolytic capacitors are connected to DC-link in order to absorb power pulsation with twice the grid frequency. On the other hand, in the active power decoupling circuit, the small capacitor can be used. However, the additional inductors and switching devices are necessary. Thus, the power density of the active power decoupling circuit is reduced. In this paper, the Pareto optimization of power density and efficiency is used to clarify the maximum power density points of the power decoupling circuits. As a result, the maximum power density of the conventional boost type active buffer, which connects a boost chopper to DC-link, is 90% of that of electrolytic capacitor topology. In addition, this paper proposes a DC-DC converter with the power decoupling capability in order to achieve higher power density than that of the passive topology. The proposed circuit, which requires no additional inductor for the power decoupling circuit, uses discontinuous current mode (DCM) for the power decoupling capability. As a result, the maximum power density is obtained to 1.1 times higher than that of passive topology. However, the total loss of switching devices is 1.5 times higher. Thus, in order to surpass the efficiency of the passive topology by the active power decoupling, the switching device is required to reduce the total loss by 35% compared to the present products.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122168085","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695611
Frederik Hahn, G. Buticchi, Marco Liserre
The modular multilevel converter (MMC) has become a very attractive solution for interfacing high voltages hybrid networks. The MMC enables scalability to different power levels, full controllability provided by IGBTs and can achieve very high efficiencies by using a low switching frequency method as the nearest level modulation (NLM). However, in order to limit failures of the power modules, the thermal stress of the submodules (SMs) should be properly studied. For NLM a capacitor voltage balancing algorithm is required and this algorithm, as demonstrated in this paper, offers already good thermal balance among the cells of the MMC. However, at low power factor, operation which could occur in case of low-voltage ride through and of reactive power injection, the mentioned algorithm is not effective anymore. This paper proposes an active thermal balancing algorithm which is embedded in the previously mentioned capacitor voltage balancing algorithm. The purpose of the active balancing is to achieve an equal heat distribution among the submodules to enhance the lifetime. The junction temperatures with and without active thermal balancing are studied in simulation for an HVDC application. The paper proves that thermal balance of MMC can be significantly improved.
{"title":"Active thermal balancing for modular multilevel converters in HVDC applications","authors":"Frederik Hahn, G. Buticchi, Marco Liserre","doi":"10.1109/EPE.2016.7695611","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695611","url":null,"abstract":"The modular multilevel converter (MMC) has become a very attractive solution for interfacing high voltages hybrid networks. The MMC enables scalability to different power levels, full controllability provided by IGBTs and can achieve very high efficiencies by using a low switching frequency method as the nearest level modulation (NLM). However, in order to limit failures of the power modules, the thermal stress of the submodules (SMs) should be properly studied. For NLM a capacitor voltage balancing algorithm is required and this algorithm, as demonstrated in this paper, offers already good thermal balance among the cells of the MMC. However, at low power factor, operation which could occur in case of low-voltage ride through and of reactive power injection, the mentioned algorithm is not effective anymore. This paper proposes an active thermal balancing algorithm which is embedded in the previously mentioned capacitor voltage balancing algorithm. The purpose of the active balancing is to achieve an equal heat distribution among the submodules to enhance the lifetime. The junction temperatures with and without active thermal balancing are studied in simulation for an HVDC application. The paper proves that thermal balance of MMC can be significantly improved.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120814382","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 : 2016-09-01DOI: 10.1109/EPE.2016.7695670
César A. Silva, Ricardo Pérez, J. Yuz, L. Empringham, L. de Lillo
The use of the EKF for induction machine sensorless control is revisited with focus on the improvement of the method for low speed operation. An appropriate discretization method is discussed, the converter non-linearities are compensated for and the observer includes stator resistance estimation. Sensorless speed closed loop experimental results show stable operation down to standstill in motoring and stable transition through zero frequency in any mode of operation. Limitations are observed for permanent operation near or at zero frequency in regenerative operation, consistent with well known theoretical limitations.
{"title":"Revisiting the EKF concept for low speed sensorless control of cage induction motors","authors":"César A. Silva, Ricardo Pérez, J. Yuz, L. Empringham, L. de Lillo","doi":"10.1109/EPE.2016.7695670","DOIUrl":"https://doi.org/10.1109/EPE.2016.7695670","url":null,"abstract":"The use of the EKF for induction machine sensorless control is revisited with focus on the improvement of the method for low speed operation. An appropriate discretization method is discussed, the converter non-linearities are compensated for and the observer includes stator resistance estimation. Sensorless speed closed loop experimental results show stable operation down to standstill in motoring and stable transition through zero frequency in any mode of operation. Limitations are observed for permanent operation near or at zero frequency in regenerative operation, consistent with well known theoretical limitations.","PeriodicalId":119358,"journal":{"name":"2016 18th European Conference on Power Electronics and Applications (EPE'16 ECCE Europe)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124604199","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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