Pub Date : 2014-12-01DOI: 10.1109/IICPE.2014.7115800
Anu Singla, A. Kaur, B. Pandey
The performance and life span of energy storage solar battery depends on its charging and discharging. Solar charge controller regulates the rate of charging and discharging of battery for its smooth and efficient operation. Solar charge sensor, component of charge controller is used to invoke full charge alarm and also discharge alarm as per the voltage level of battery. Solar charge sensor consumes certain power. LVCMOS I/O standards is the low voltage complementary metal oxide semiconductor. There are 4 different LVCMOS available in 28nm technology based Artix-7 FPGA. We are proposing I/O standards for solar charge sensor in order to achieve energy efficiency with solar charge sensor. There is 60% reduction in I/O power, when we use LVCMOS15 in place of LVCMOS33 in solar charge sensor design at 900MHz. Similarly, we are saving 51.85% I/O power, when we use LVCMOS18 in place of LVCMOS33 in solar charge sensor design operating at 5 GHz. Similarly, we are saving 32.31% IO power, when we use LVCMOS25 in place of LVCMOS33 in solar charge sensor design operating at 60 GHz.
{"title":"LVCMOS based energy efficient solar charge sensor design on FPGA","authors":"Anu Singla, A. Kaur, B. Pandey","doi":"10.1109/IICPE.2014.7115800","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115800","url":null,"abstract":"The performance and life span of energy storage solar battery depends on its charging and discharging. Solar charge controller regulates the rate of charging and discharging of battery for its smooth and efficient operation. Solar charge sensor, component of charge controller is used to invoke full charge alarm and also discharge alarm as per the voltage level of battery. Solar charge sensor consumes certain power. LVCMOS I/O standards is the low voltage complementary metal oxide semiconductor. There are 4 different LVCMOS available in 28nm technology based Artix-7 FPGA. We are proposing I/O standards for solar charge sensor in order to achieve energy efficiency with solar charge sensor. There is 60% reduction in I/O power, when we use LVCMOS15 in place of LVCMOS33 in solar charge sensor design at 900MHz. Similarly, we are saving 51.85% I/O power, when we use LVCMOS18 in place of LVCMOS33 in solar charge sensor design operating at 5 GHz. Similarly, we are saving 32.31% IO power, when we use LVCMOS25 in place of LVCMOS33 in solar charge sensor design operating at 60 GHz.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":" 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120832684","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115828
J. Arya, L. Saini
Now-a-days effective solar power generation is necessary for smart grid implementation. Grid fed single-stage single-phase solar inverter with incremental conductance MPPT (INC+ regulator), closed loop current and voltage controller is implemented. In normal condition inverter current T.H.D is under the limit as per IEEE-519. At the time of fault, inverter having voltage imbalance, which may lead to damage. System fault ride through capability is improved by using Series Dynamic Braking Resistor (SDBR) with high current error as control parameter. Protection scheme maintains the grid code and hence the solar inverter needs not to be disconnected from the grid during the fault. Comparative results are obtained by simulation in MATLAB R2013a software. The whole system can be used in local distribution system as an application in future effectively.
{"title":"Single stage single phase solar inverter with improved fault ride through capability","authors":"J. Arya, L. Saini","doi":"10.1109/IICPE.2014.7115828","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115828","url":null,"abstract":"Now-a-days effective solar power generation is necessary for smart grid implementation. Grid fed single-stage single-phase solar inverter with incremental conductance MPPT (INC+ regulator), closed loop current and voltage controller is implemented. In normal condition inverter current T.H.D is under the limit as per IEEE-519. At the time of fault, inverter having voltage imbalance, which may lead to damage. System fault ride through capability is improved by using Series Dynamic Braking Resistor (SDBR) with high current error as control parameter. Protection scheme maintains the grid code and hence the solar inverter needs not to be disconnected from the grid during the fault. Comparative results are obtained by simulation in MATLAB R2013a software. The whole system can be used in local distribution system as an application in future effectively.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122653089","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115737
A. Pathak, M. Sharma
Shunt capacitor banks are installed by developers pooling stations for management of reactive power for a wind farm. Operation of shunt capacitor banks is manually and accordingly there is a wide variation in wind power plant power factor of 0.9 lagging to 0.9 leading. Due to large variations in wind generation power factor, reactive power flows on transmission lines are also variable and accordingly there is a wide variation in power transmission system voltage from minimum 0.8 p.u. to a maximum of 1.20 p.u. Due to low & high power system voltages, transmission lines are tripped resulting constrained in a wind power evacuation. Considering the high penetration of wind power in the system, in this paper, Static Var Compensator (SVC) is proposed at 400kV GSS Jaisalmerfor large scale wind power penetrated power system, for mitigation of wind power generators reactive power. Simulation studies have been carried out to validate the effectiveness of the SVC for voltage control with the variation in wind power generation power factor. Case studies are carried out in 19-bus system in Western Rajasthan area where wind power penetration is even more than 2000MW to demonstrate the performance of the SVC taking the consolidated effect of voltage behavior with and without SVC at a different power factor. Wind power, penetrated part of Rajasthan power system has been modeled using Mi.-Power system analysis software. Results of tests conducted on the model system in various possible field conditions are presented and discussed.
{"title":"Mitigation of reactive power requirements of large scale wind power generation in Western Rajasthan using Static Var Compensator","authors":"A. Pathak, M. Sharma","doi":"10.1109/IICPE.2014.7115737","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115737","url":null,"abstract":"Shunt capacitor banks are installed by developers pooling stations for management of reactive power for a wind farm. Operation of shunt capacitor banks is manually and accordingly there is a wide variation in wind power plant power factor of 0.9 lagging to 0.9 leading. Due to large variations in wind generation power factor, reactive power flows on transmission lines are also variable and accordingly there is a wide variation in power transmission system voltage from minimum 0.8 p.u. to a maximum of 1.20 p.u. Due to low & high power system voltages, transmission lines are tripped resulting constrained in a wind power evacuation. Considering the high penetration of wind power in the system, in this paper, Static Var Compensator (SVC) is proposed at 400kV GSS Jaisalmerfor large scale wind power penetrated power system, for mitigation of wind power generators reactive power. Simulation studies have been carried out to validate the effectiveness of the SVC for voltage control with the variation in wind power generation power factor. Case studies are carried out in 19-bus system in Western Rajasthan area where wind power penetration is even more than 2000MW to demonstrate the performance of the SVC taking the consolidated effect of voltage behavior with and without SVC at a different power factor. Wind power, penetrated part of Rajasthan power system has been modeled using Mi.-Power system analysis software. Results of tests conducted on the model system in various possible field conditions are presented and discussed.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128409826","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115836
Tousif Khan N, K. Sundareswaran
Buck converters are employed in several applications such as laptops, switched mode power supply, electronic gadgets, battery charging and communication networks. In order to have good regulation of capacitor voltage, Buck converters are generally provided with a feedback control mechanism. Since the converter dynamics changes from ON time period to OFF time period of the power electronic switch, the traditionally designed feedback controller provides only near-satisfactory voltage regulation. Aiming to obtain a more robust controller, which can track the desired voltage profile over large domain of operating points, the controller design for the feedback control of Buck DC-DC converter is constructed as an optimization problem and then the solution is acquired through a recently developed optimization technique known as queen bee evolution based Genetic Algorithm. The theoretical notions and implementation of the proposed methodology towards the search of a robust feedback control parameters for Buck converters are discussed in this paper. Extensive simulation and experimental studies under the presence of eventualities like matched and mismatched uncertainties are compared with conventional Genetic Algorithm, which thereby confirms the validity of the new approach.
{"title":"Voltage regulation enhancement in a Buck type DC-DC converter using queen bee evolution based Genetic Algorithm","authors":"Tousif Khan N, K. Sundareswaran","doi":"10.1109/IICPE.2014.7115836","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115836","url":null,"abstract":"Buck converters are employed in several applications such as laptops, switched mode power supply, electronic gadgets, battery charging and communication networks. In order to have good regulation of capacitor voltage, Buck converters are generally provided with a feedback control mechanism. Since the converter dynamics changes from ON time period to OFF time period of the power electronic switch, the traditionally designed feedback controller provides only near-satisfactory voltage regulation. Aiming to obtain a more robust controller, which can track the desired voltage profile over large domain of operating points, the controller design for the feedback control of Buck DC-DC converter is constructed as an optimization problem and then the solution is acquired through a recently developed optimization technique known as queen bee evolution based Genetic Algorithm. The theoretical notions and implementation of the proposed methodology towards the search of a robust feedback control parameters for Buck converters are discussed in this paper. Extensive simulation and experimental studies under the presence of eventualities like matched and mismatched uncertainties are compared with conventional Genetic Algorithm, which thereby confirms the validity of the new approach.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121573972","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115835
A. Anand kumar, P. Thakura
In this paper, an algorithm is developed that enable a single phase matrix converter (SPMC) to perform a function of cycloconverter and of inverter i.e. act as frequency changer and also convert DC to AC. The algorithm is first implemented on Matlab simulink software. Simulation results are presented for SPMC as a cycloconverter (at different output frequency) and as an inverter (DC to AC). Simulated results are verified with experimental result. Also a laboratory model test rig of the SPMC as a cycloconverter and inverter has been developed using microcontroller to experimentally verify the result. Good result was obtained between simulation and experiments.
{"title":"Hardware development and implementation of single phase matrix converter as a cycloconverter and as an inverter","authors":"A. Anand kumar, P. Thakura","doi":"10.1109/IICPE.2014.7115835","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115835","url":null,"abstract":"In this paper, an algorithm is developed that enable a single phase matrix converter (SPMC) to perform a function of cycloconverter and of inverter i.e. act as frequency changer and also convert DC to AC. The algorithm is first implemented on Matlab simulink software. Simulation results are presented for SPMC as a cycloconverter (at different output frequency) and as an inverter (DC to AC). Simulated results are verified with experimental result. Also a laboratory model test rig of the SPMC as a cycloconverter and inverter has been developed using microcontroller to experimentally verify the result. Good result was obtained between simulation and experiments.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"85 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130666709","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115767
K. Steela, B. Rajpurohit
This paper proposes a fuzzy logic controller for dc-link voltage regulation to enhance the performance of two widely used active power filter control strategies, namely, d-q method and id-iq method. The dynamic performance of the systems are evaluated under different supply conditions and compared with the performances of the two control strategies working with PI controller. The effectiveness of the fuzzy logic controller, in terms of total harmonic distortion (THD) in supply current and regulation of dc-link voltage is validated.
{"title":"Enhancing performance of APF by fuzzy controller","authors":"K. Steela, B. Rajpurohit","doi":"10.1109/IICPE.2014.7115767","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115767","url":null,"abstract":"This paper proposes a fuzzy logic controller for dc-link voltage regulation to enhance the performance of two widely used active power filter control strategies, namely, d-q method and id-iq method. The dynamic performance of the systems are evaluated under different supply conditions and compared with the performances of the two control strategies working with PI controller. The effectiveness of the fuzzy logic controller, in terms of total harmonic distortion (THD) in supply current and regulation of dc-link voltage is validated.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129642857","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115848
Ridhi Saini
Electric vehicles need to be charged at public places in a secured manner which is advantageous both for utility as well as consumer. This paper discusses simulation and implementation of authentication or digital lock of PIN code used for secure transaction at unattended public electric vehicle charging station on XILINX ISE Project Navigator Ver.8.2 using Verilog HDL and simulated using Modelsim software.
电动汽车需要在公共场所以安全的方式充电，这对公用事业和消费者都有利。本文讨论了在XILINX ISE Project Navigator Ver.8.2平台上，利用Verilog HDL对无人值机公共电动汽车充电站安全交易用PIN码认证或数字锁的仿真与实现，并利用Modelsim软件进行了仿真。
{"title":"Secured charging of electric vehicles at unattended stations using Verilog HDL","authors":"Ridhi Saini","doi":"10.1109/IICPE.2014.7115848","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115848","url":null,"abstract":"Electric vehicles need to be charged at public places in a secured manner which is advantageous both for utility as well as consumer. This paper discusses simulation and implementation of authentication or digital lock of PIN code used for secure transaction at unattended public electric vehicle charging station on XILINX ISE Project Navigator Ver.8.2 using Verilog HDL and simulated using Modelsim software.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129760698","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7145018
S. S. Ahmad, G. Narayanan
Proportional Integral (PI) controller based current control is widely employed in different motor drives. However, in case of switched reluctance motor (SRM), the non-linearity and double saliency of the motor make the modelling and controller design challenging. This paper attempts linearisation of the flux linkage characteristic of the SRM at different operating points. The models include saturation and back-emf in an effective manner, as compared to existing methods. The different linearised models are evaluated for the purpose of current controller design. An effective method of controller design is found which directly relates the machine parameters to the controller gains.
{"title":"Linearised modelling of switched reluctance motor for closed loop current control","authors":"S. S. Ahmad, G. Narayanan","doi":"10.1109/IICPE.2014.7145018","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7145018","url":null,"abstract":"Proportional Integral (PI) controller based current control is widely employed in different motor drives. However, in case of switched reluctance motor (SRM), the non-linearity and double saliency of the motor make the modelling and controller design challenging. This paper attempts linearisation of the flux linkage characteristic of the SRM at different operating points. The models include saturation and back-emf in an effective manner, as compared to existing methods. The different linearised models are evaluated for the purpose of current controller design. An effective method of controller design is found which directly relates the machine parameters to the controller gains.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125702625","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115790
Madhu Sharma, K. Bansal, D. Buddhi
High operating temperature decreases photo voltaic module efficiency. Normal Operating Cell Temperature, NOCT of silicon crystalline is about 49°C as reported. A cooling unit with reverse flow water circulation is designed, fabricated and applied on PV back surface to partially avoid undesirable effect of its temperature increase. This modified module with cooling unit and similar non-cooled modules are installed outdoor identically at University of Petroleum and Energy Studies campus, Dehradun. Installed Normal Operating Cell Temperature, INOCT of both the modules are determined and compared by varying water flow rate from cooling unit. And also water flow rate is optimized to maintain minimum possible operating temperature.
{"title":"Operating temperature of PV module modified with surface cooling unit in real time condition","authors":"Madhu Sharma, K. Bansal, D. Buddhi","doi":"10.1109/IICPE.2014.7115790","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115790","url":null,"abstract":"High operating temperature decreases photo voltaic module efficiency. Normal Operating Cell Temperature, NOCT of silicon crystalline is about 49°C as reported. A cooling unit with reverse flow water circulation is designed, fabricated and applied on PV back surface to partially avoid undesirable effect of its temperature increase. This modified module with cooling unit and similar non-cooled modules are installed outdoor identically at University of Petroleum and Energy Studies campus, Dehradun. Installed Normal Operating Cell Temperature, INOCT of both the modules are determined and compared by varying water flow rate from cooling unit. And also water flow rate is optimized to maintain minimum possible operating temperature.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114723532","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 : 2014-12-01DOI: 10.1109/IICPE.2014.7115854
P. P. Acharya, Vishal S. Rangras
Advancement in Multilevel Inverter Technologies and its Control Techniques has been emerging in leaps and bounds. Such an inclination towards this area is because of its high power handling capability as well as improved power quality. Low Total Harmonic Distortion (THD) and less thermal Stress on Switches and improved performance are its added advantages. Switching strategies plays a very important role in optimizing inverter performance parameters. In this paper a novel multicarrier sine Pulse Width Modulation (PWM) Phase Disposition technique is introduced which significantly reduces THD. The proposed switching technique is described using relevant mathematical analysis, and results are obtained from simulation study, which consequently illustrates the improved performance of the overall system as compared to conventional one.
{"title":"Modified sine wave phase disposition PWM technique for harmonic reduction in multilevel inverter fed drives","authors":"P. P. Acharya, Vishal S. Rangras","doi":"10.1109/IICPE.2014.7115854","DOIUrl":"https://doi.org/10.1109/IICPE.2014.7115854","url":null,"abstract":"Advancement in Multilevel Inverter Technologies and its Control Techniques has been emerging in leaps and bounds. Such an inclination towards this area is because of its high power handling capability as well as improved power quality. Low Total Harmonic Distortion (THD) and less thermal Stress on Switches and improved performance are its added advantages. Switching strategies plays a very important role in optimizing inverter performance parameters. In this paper a novel multicarrier sine Pulse Width Modulation (PWM) Phase Disposition technique is introduced which significantly reduces THD. The proposed switching technique is described using relevant mathematical analysis, and results are obtained from simulation study, which consequently illustrates the improved performance of the overall system as compared to conventional one.","PeriodicalId":206767,"journal":{"name":"2014 IEEE 6th India International Conference on Power Electronics (IICPE)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123055188","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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