Pub Date : 2014-11-01DOI: 10.1109/PEAC.2014.7037889
JieXing Luo, Guiping Du, Junxiang Fang
The resonance characteristics of ultrasonic transducer are analyzed based on the equivalent circuit of transducer and the quantitative calculation of admittance circle, and a control method of frequency tracking based on variable step length is proposed, and the limits of step switching are deduced, and the control parameters of the control method based on variable step length is designed in this paper. The results of simulation and experiment show that the system based on the control method can control output frequency in high precision. And while ultrasonic power supply ensure steady-state error minimum, holding a good dynamic performance, which meets the requirements of the technology of ultrasonic power supply.
{"title":"The research on phase lock method of ultrasonic power supply with variable step length control","authors":"JieXing Luo, Guiping Du, Junxiang Fang","doi":"10.1109/PEAC.2014.7037889","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037889","url":null,"abstract":"The resonance characteristics of ultrasonic transducer are analyzed based on the equivalent circuit of transducer and the quantitative calculation of admittance circle, and a control method of frequency tracking based on variable step length is proposed, and the limits of step switching are deduced, and the control parameters of the control method based on variable step length is designed in this paper. The results of simulation and experiment show that the system based on the control method can control output frequency in high precision. And while ultrasonic power supply ensure steady-state error minimum, holding a good dynamic performance, which meets the requirements of the technology of ultrasonic power supply.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"47 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116397445","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037965
Jingang Li, Liping Wang, Qi Sun
Modern high-frequency induction heating technology puts forward higher requirements for load matching of the induction heating power supply. LLC resonant load circuit can replace the traditional induction heating load matching transformer, and increase power density. This paper analyzes the load matching characteristics of LLC load resonant circuit in high frequency induction heating power supply, and gives the parameter selection method of matching components. At last, combining with phase-shifting pulse-width modulation (PWM) control method, the phase-shifting induction heating experiment platform based on LLC load resonant circuit is established. Experimental results show that the performance of LLC circuit in high frequency induction heating power supply load matching is excellent.
{"title":"Research on high-frequency induction heating load-matched based on LLC resonant circuit","authors":"Jingang Li, Liping Wang, Qi Sun","doi":"10.1109/PEAC.2014.7037965","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037965","url":null,"abstract":"Modern high-frequency induction heating technology puts forward higher requirements for load matching of the induction heating power supply. LLC resonant load circuit can replace the traditional induction heating load matching transformer, and increase power density. This paper analyzes the load matching characteristics of LLC load resonant circuit in high frequency induction heating power supply, and gives the parameter selection method of matching components. At last, combining with phase-shifting pulse-width modulation (PWM) control method, the phase-shifting induction heating experiment platform based on LLC load resonant circuit is established. Experimental results show that the performance of LLC circuit in high frequency induction heating power supply load matching is excellent.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"10 45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122696165","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7038038
Haijin Li, Jianan Zhou, Zhaoyu Liu, Dehong Xu
In this paper, demand for Solid State DC Circuit Breaker for Super Uninterruptible Power Supply (UPS) is analyzed firstly. Design of the Solid State DC Circuit Breaker is investigated. Then the optimized structure with RCD+MOV is designed to reduce the voltage stress of the power device. Furthermore, the detection of short-circuit current is provided. Finally, a prototype is built to verify the design.
{"title":"Solid State DC Circuit Breaker for Super Uninterruptible Power Supply","authors":"Haijin Li, Jianan Zhou, Zhaoyu Liu, Dehong Xu","doi":"10.1109/PEAC.2014.7038038","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038038","url":null,"abstract":"In this paper, demand for Solid State DC Circuit Breaker for Super Uninterruptible Power Supply (UPS) is analyzed firstly. Design of the Solid State DC Circuit Breaker is investigated. Then the optimized structure with RCD+MOV is designed to reduce the voltage stress of the power device. Furthermore, the detection of short-circuit current is provided. Finally, a prototype is built to verify the design.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"83 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114128774","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7038070
Dong Sun, Xikun Chen, Y. Ruan
Based on the equivalent circuit model (ECM) of lithium-ion battery, this paper introduces an autoregressive and moving average with exogenous input (ARMAX) model. A recursive extended least square algorithm with forgetting factor is employed as the model parameter identification method, because there is a colored noise in operating process. Then HPPC test was conducted on a 20Ah LiFePO4 cell and the RC ECM parameters available were identified under different SOCs and different current rates. For higher accuracy SOC estimation and uncertainty reduction, strong tracking filter based on cubature Kalman framework (ST-CKF) is adopted as the SOC estimator to compensate for the drawback of nonlinear Kalman filter. The experimental results in UDDS test show that the ST-CKF estimator is more accurate than extended Kalman filter algorithm with the maximum estimated error about 1.8%.
{"title":"Research on modeling and state of charge estimation for lithium-ion battery","authors":"Dong Sun, Xikun Chen, Y. Ruan","doi":"10.1109/PEAC.2014.7038070","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038070","url":null,"abstract":"Based on the equivalent circuit model (ECM) of lithium-ion battery, this paper introduces an autoregressive and moving average with exogenous input (ARMAX) model. A recursive extended least square algorithm with forgetting factor is employed as the model parameter identification method, because there is a colored noise in operating process. Then HPPC test was conducted on a 20Ah LiFePO4 cell and the RC ECM parameters available were identified under different SOCs and different current rates. For higher accuracy SOC estimation and uncertainty reduction, strong tracking filter based on cubature Kalman framework (ST-CKF) is adopted as the SOC estimator to compensate for the drawback of nonlinear Kalman filter. The experimental results in UDDS test show that the ST-CKF estimator is more accurate than extended Kalman filter algorithm with the maximum estimated error about 1.8%.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130410911","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037996
Xiuyi Li, Miao Zhu, Jianwen Zhang, X. Cai
The Switched Z-source Isolated Bidirectional DC-DC Converter (SZIBDC) is a novel topology that inherits the advantages of Dual Active Bridge (DAB) while overcoming its disadvantages. This paper presents the small-signal model of open-loop SZIBDC firstly. After that, five kinds of close-loop control strategies based on PI-regulator or Fuzzy Logic Controller (FLC) are theoretically analyzed and validated by simulation results. Their performance has been investigated from the perspective of steady and transient states. Finally a comparative study is made and relevant conclusions are drawn.
{"title":"Modeling and close-loop control strategies of Switched Z-source Isolated Bidirectional DC-DC Converter","authors":"Xiuyi Li, Miao Zhu, Jianwen Zhang, X. Cai","doi":"10.1109/PEAC.2014.7037996","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037996","url":null,"abstract":"The Switched Z-source Isolated Bidirectional DC-DC Converter (SZIBDC) is a novel topology that inherits the advantages of Dual Active Bridge (DAB) while overcoming its disadvantages. This paper presents the small-signal model of open-loop SZIBDC firstly. After that, five kinds of close-loop control strategies based on PI-regulator or Fuzzy Logic Controller (FLC) are theoretically analyzed and validated by simulation results. Their performance has been investigated from the perspective of steady and transient states. Finally a comparative study is made and relevant conclusions are drawn.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126519899","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037867
Hao Zhai, F. Zhuo, Hao Yi, Dong Zhang, Zhiqing Geng, Kewei Li
PR controller in stationary frame which is equivalent to PI controller in synchronous frame has been widely used in the application of PV inverters. While little attention has been devoted to VR(vector-resonant) controller in the application of PV inverters. VR controller in stationary frame is equivalent to VPI(vector PI) controller in synchronous frame, which takes decoupling into consideration and has better performance than PI controller. This paper proves the theory of controller transformation between stationary frame and synchronous frame based on vector modeling, and analyses the feasibility of VR controller applied in PV inverters. In comparison with PR controller, the advantages and disadvantages of VR controller are figured. VR controller can control AC signals of positive sequence and negative sequence simultaneously with good accuracy, and can filter harmonic components in current instructions. Based on these characteristics, a new method of generating current instructions of PV inverters was proposed for VR controller, which doesn't need phase lock loop but may contain harmonics in the instructions when the grid voltage has harmonics. The drawback of VR controller is its low transient response. As a result, if VR controller is used in PV inverters, the computation burden of current loop can decrease a lot keeping good performance, but the period of voltage loop control should be set larger. Simulation results based on PSIM validate the theoretical analysis.
{"title":"A novel method for photovoltaic inverter applying vector resonant controller","authors":"Hao Zhai, F. Zhuo, Hao Yi, Dong Zhang, Zhiqing Geng, Kewei Li","doi":"10.1109/PEAC.2014.7037867","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037867","url":null,"abstract":"PR controller in stationary frame which is equivalent to PI controller in synchronous frame has been widely used in the application of PV inverters. While little attention has been devoted to VR(vector-resonant) controller in the application of PV inverters. VR controller in stationary frame is equivalent to VPI(vector PI) controller in synchronous frame, which takes decoupling into consideration and has better performance than PI controller. This paper proves the theory of controller transformation between stationary frame and synchronous frame based on vector modeling, and analyses the feasibility of VR controller applied in PV inverters. In comparison with PR controller, the advantages and disadvantages of VR controller are figured. VR controller can control AC signals of positive sequence and negative sequence simultaneously with good accuracy, and can filter harmonic components in current instructions. Based on these characteristics, a new method of generating current instructions of PV inverters was proposed for VR controller, which doesn't need phase lock loop but may contain harmonics in the instructions when the grid voltage has harmonics. The drawback of VR controller is its low transient response. As a result, if VR controller is used in PV inverters, the computation burden of current loop can decrease a lot keeping good performance, but the period of voltage loop control should be set larger. Simulation results based on PSIM validate the theoretical analysis.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"483 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127959135","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037946
Yuan Li, Shiyan Yang, Wei Yang, Jingfang Wang
This paper proposes a novel robust method for three-phase rectifier system with high quality for higher power applications. The system consists of two stages: The front stage combines the unique features of a low-kilovoltampere 12-pulse rectifier scheme along with a single-phase pwm rectifier scheme to shape the input current to a sinusoidal waveshape. The single-phase pwm rectifier stage is rated at 0.02 pu and assists in shaping the input current under varying load conditions, which concentrate extract specific harmonic energy and feeds it back to the 12-pulse rectifier system output side to reuse harmonic energy. Which is suitable for the clean-power utility interface of power electronic system. The post-stage is buffered soft-switching dc converter, the output voltage is adjustable continuously in a wide range. The proposed system is rugged and, in the event the active control were to fail, the system reverts to 12-pulse operation with fifth and seventh harmonic cancellation. Analysis and design of the system is examined in detail, and simulation and experimental results on a 60-kW prototype are shown. Results of the proposed system verify the validity and feasibility of the proposed method.
{"title":"A novel robust method for three - phase high power rectifier system with high quality","authors":"Yuan Li, Shiyan Yang, Wei Yang, Jingfang Wang","doi":"10.1109/PEAC.2014.7037946","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037946","url":null,"abstract":"This paper proposes a novel robust method for three-phase rectifier system with high quality for higher power applications. The system consists of two stages: The front stage combines the unique features of a low-kilovoltampere 12-pulse rectifier scheme along with a single-phase pwm rectifier scheme to shape the input current to a sinusoidal waveshape. The single-phase pwm rectifier stage is rated at 0.02 pu and assists in shaping the input current under varying load conditions, which concentrate extract specific harmonic energy and feeds it back to the 12-pulse rectifier system output side to reuse harmonic energy. Which is suitable for the clean-power utility interface of power electronic system. The post-stage is buffered soft-switching dc converter, the output voltage is adjustable continuously in a wide range. The proposed system is rugged and, in the event the active control were to fail, the system reverts to 12-pulse operation with fifth and seventh harmonic cancellation. Analysis and design of the system is examined in detail, and simulation and experimental results on a 60-kW prototype are shown. Results of the proposed system verify the validity and feasibility of the proposed method.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121680767","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037955
Boping Yang, Shuailin Du, Wenjie Chen, Cheng Deng, Dehong Xu
The wireless power transfer (WPT) system for electric vehicles requires high efficiency, lightweight, compact and be suited to big air gap. The WPT system has low coupling coefficient, which is far different from the traditional transformer. Optimal parameters design approach for resonant converter with S-S compensation for WPT is investigated. 85kHz and 20kHz parameters design are introduced in the paper. The validity of the proposed parameters design of 85kHz and 20kHz are verified by experimental results obtained from a 10kW resonant converter prototype with 150mm air gap. Finally the results of 85kHz and 20kHz optimal parameters design experiment are compared.
{"title":"Optimal parameters design for series-series resonant converter for wireless power transfer","authors":"Boping Yang, Shuailin Du, Wenjie Chen, Cheng Deng, Dehong Xu","doi":"10.1109/PEAC.2014.7037955","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037955","url":null,"abstract":"The wireless power transfer (WPT) system for electric vehicles requires high efficiency, lightweight, compact and be suited to big air gap. The WPT system has low coupling coefficient, which is far different from the traditional transformer. Optimal parameters design approach for resonant converter with S-S compensation for WPT is investigated. 85kHz and 20kHz parameters design are introduced in the paper. The validity of the proposed parameters design of 85kHz and 20kHz are verified by experimental results obtained from a 10kW resonant converter prototype with 150mm air gap. Finally the results of 85kHz and 20kHz optimal parameters design experiment are compared.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115838115","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037834
Jun Wang, Cong Wang, Hong Cheng, Guanglin Sha
This article has proposed a control strategy for balancing the capacitors' voltage of cascaded H-bridge rectifier. The working principle of cascaded H-bridge rectifier has been described, as well as the balancing boundary condition of capacitors' voltage. Then, the dual modulation curves control strategy has been proposed for balancing the capacitors' voltage in dc side of the rectifier. Furthermore, the logic expression of dual modulation curves strategy has also been discussed to handle with multiple cascaded H-bridges situation. With the proposed control strategy, the capacitors' voltage can be balanced under the unbalanced load condition. The simulation and experiments are presents to verify the performance of the proposed control strategy.
{"title":"Extended dual modulation curves voltage balancing strategy for cascaded H-bridge rectifier","authors":"Jun Wang, Cong Wang, Hong Cheng, Guanglin Sha","doi":"10.1109/PEAC.2014.7037834","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037834","url":null,"abstract":"This article has proposed a control strategy for balancing the capacitors' voltage of cascaded H-bridge rectifier. The working principle of cascaded H-bridge rectifier has been described, as well as the balancing boundary condition of capacitors' voltage. Then, the dual modulation curves control strategy has been proposed for balancing the capacitors' voltage in dc side of the rectifier. Furthermore, the logic expression of dual modulation curves strategy has also been discussed to handle with multiple cascaded H-bridges situation. With the proposed control strategy, the capacitors' voltage can be balanced under the unbalanced load condition. The simulation and experiments are presents to verify the performance of the proposed control strategy.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115863961","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037899
D. Reusch, J. Strydom, A. Lidow
Continuing to raise the bar for power conversion performance, eGaN FETs are steadily improving performance in high power density and high current applications. In this paper we will discuss the latest developments in DC-DC converters, including a major improvement in eGaN FETs with the latest generation devices. This new family of eGaN FETs is keeping Moore's Law alive with significant gains in key switching figures of merit that widen the performance gap with the power MOSFET in high frequency power conversion. The final demonstrations will include a 12 V to 1.2 V, 40 A POL converter operating at a switching frequency of 1 MHz achieving efficiencies above 91.5%, and a 48 V to 12 V, 30 A non-isolated buck DC-DC intermediate bus converter operating at a switching frequency of 300 kHz achieving efficiencies above 98%.
{"title":"Highly efficient gallium nitride transistors designed for high power density and high output current DC-DC converters","authors":"D. Reusch, J. Strydom, A. Lidow","doi":"10.1109/PEAC.2014.7037899","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037899","url":null,"abstract":"Continuing to raise the bar for power conversion performance, eGaN FETs are steadily improving performance in high power density and high current applications. In this paper we will discuss the latest developments in DC-DC converters, including a major improvement in eGaN FETs with the latest generation devices. This new family of eGaN FETs is keeping Moore's Law alive with significant gains in key switching figures of merit that widen the performance gap with the power MOSFET in high frequency power conversion. The final demonstrations will include a 12 V to 1.2 V, 40 A POL converter operating at a switching frequency of 1 MHz achieving efficiencies above 91.5%, and a 48 V to 12 V, 30 A non-isolated buck DC-DC intermediate bus converter operating at a switching frequency of 300 kHz achieving efficiencies above 98%.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130943487","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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