Pub Date : 2014-11-01DOI: 10.1109/PEAC.2014.7037887
Ye Zhu, B. Xu, Linglin Chen, Dezhi Dong, Ping-Yi Lin, Dehong Xu
Multi-Functional Bidirectional AC/DC T-type 3-Level Converter for Super UPS is investigated in this paper. The AC/DC converter is used as the interfaced between DC Bus and Energy Source or Load. According to the components (grid, gas turbines, AC loads) connected in AC side, The AC/DC converter operates at AC voltage source mode, Power source mode or DC voltage source mode. A control scheme for the Multi-Functional Bidirectional AC/DC converter is studied. Finally the design of the AC/DC converter is verified by experiment on a 100kW AC/DC converter prototype.
{"title":"Multi-Functional Bidirectional AC/DC T-type 3-Level Converter for Super UPS","authors":"Ye Zhu, B. Xu, Linglin Chen, Dezhi Dong, Ping-Yi Lin, Dehong Xu","doi":"10.1109/PEAC.2014.7037887","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037887","url":null,"abstract":"Multi-Functional Bidirectional AC/DC T-type 3-Level Converter for Super UPS is investigated in this paper. The AC/DC converter is used as the interfaced between DC Bus and Energy Source or Load. According to the components (grid, gas turbines, AC loads) connected in AC side, The AC/DC converter operates at AC voltage source mode, Power source mode or DC voltage source mode. A control scheme for the Multi-Functional Bidirectional AC/DC converter is studied. Finally the design of the AC/DC converter is verified by experiment on a 100kW AC/DC converter prototype.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"82 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":"131312183","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.2014.7037977
Jin Hu, Zheng-yu Lu, Huipin Lin, Feng-wu Zhou
High Pressure Sodium (HPS) is widely used in street lighting applications because of its maturity, reliability, high lighting efficiency, long lifetime and low cost. Light Emitting Diode (LED) is expected as the next generation of lighting source due to its continuously improving luminous efficacy, better color characteristic and super long life-time. The two lighting sources may coexist in street lighting applications for a long time. A novel HPS and LED compatible driver is proposed which is rather suitable and flexible for driving HPS and LED in street lighting applications. The proposed driver combines the LLC and LCC resonant circuits into a flexible LLCC resonant tank. The LLCC resonant tank may change to LLC or isolated LCC circuit based on the lighting source. It inherits the traditional HPS and LED drivers' ZVS characteristics and dimmable function. The experiments of driving HPS and LED on a prototype verify the effectiveness of proposed driver.
{"title":"A novel HPS and LED compatible driver with flexible resonant tank","authors":"Jin Hu, Zheng-yu Lu, Huipin Lin, Feng-wu Zhou","doi":"10.1109/PEAC.2014.7037977","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037977","url":null,"abstract":"High Pressure Sodium (HPS) is widely used in street lighting applications because of its maturity, reliability, high lighting efficiency, long lifetime and low cost. Light Emitting Diode (LED) is expected as the next generation of lighting source due to its continuously improving luminous efficacy, better color characteristic and super long life-time. The two lighting sources may coexist in street lighting applications for a long time. A novel HPS and LED compatible driver is proposed which is rather suitable and flexible for driving HPS and LED in street lighting applications. The proposed driver combines the LLC and LCC resonant circuits into a flexible LLCC resonant tank. The LLCC resonant tank may change to LLC or isolated LCC circuit based on the lighting source. It inherits the traditional HPS and LED drivers' ZVS characteristics and dimmable function. The experiments of driving HPS and LED on a prototype verify the effectiveness of proposed driver.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"63 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":"114984676","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.2014.7038025
Hao Peng, Chin Chang
For a constant on time controller to be stable with all ceramic output capacitance, a virtual ESR (Equivalent Series Resistance) circuit is needed to inject the required ripple voltage into the FB (Feedback) node. This paper proposes a new stability criterion, which is that the FB node ripple voltage need to have the same phase as the inductor current and have certain amplitude to filter out noise. Based on this stability criterion, the virtual ESR circuit is analyzed. The contributions from the phase node voltage, the inductor current and the output voltage are derived with superposition. Two methods to design the virtual ESR circuit, the In Phase Dominance Method and the Phase Cancellation Method, are proposed and experimentally verified. Comparisons between real ESR and the virtual ESR are made. The effects of virtual ESR circuit on load transient responses, power saving mode waveforms and output voltage setting are also discussed.
{"title":"Analysis and design of virtual ESR circuit with constant on time control","authors":"Hao Peng, Chin Chang","doi":"10.1109/PEAC.2014.7038025","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038025","url":null,"abstract":"For a constant on time controller to be stable with all ceramic output capacitance, a virtual ESR (Equivalent Series Resistance) circuit is needed to inject the required ripple voltage into the FB (Feedback) node. This paper proposes a new stability criterion, which is that the FB node ripple voltage need to have the same phase as the inductor current and have certain amplitude to filter out noise. Based on this stability criterion, the virtual ESR circuit is analyzed. The contributions from the phase node voltage, the inductor current and the output voltage are derived with superposition. Two methods to design the virtual ESR circuit, the In Phase Dominance Method and the Phase Cancellation Method, are proposed and experimentally verified. Comparisons between real ESR and the virtual ESR are made. The effects of virtual ESR circuit on load transient responses, power saving mode waveforms and output voltage setting are also discussed.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"2 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":"132339314","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.2014.7037873
C. N. Ho, R. T. Li, E. Bianda
The paper presents a gate driver for current-control power semiconductor devices such as BJT. The gate driver has a capability to reduce switching time duration of a power transistor, both in turn-on and turn-off transients. Besides, when the transistor is in static conduction periods, the driver gives a high driving current to the power transistor with holding up by a low supply voltage. This leads to reduce power losses of the driver and switching losses of the transistor. Then, an efficient switching process happens with the whole power switching unit. The paper provides PSpice simulated switching results using a manufacturer provided 1.2kV SiC BJT model to confirm the feasibility of the proposed driver and compare it with a conventional unipolar driver. The results are in good agreement with the theoretical prediction.
本文介绍了一种用于电流控制型功率半导体器件的栅极驱动器。栅极驱动器有能力减少功率晶体管的开关时间持续时间，无论是在导通和关断瞬态。此外，当晶体管处于静态导通期时，驱动器在低电源电压的支撑下向功率晶体管提供高驱动电流。这样可以减少驱动器的功率损耗和晶体管的开关损耗。然后，整个电源开关单元进行有效的切换过程。本文使用厂商提供的1.2kV SiC BJT模型提供PSpice模拟开关结果，以验证所提出驱动器的可行性，并将其与传统单极驱动器进行比较。计算结果与理论预测吻合较好。
{"title":"An efficient current-source power bipolar junction transistor driver","authors":"C. N. Ho, R. T. Li, E. Bianda","doi":"10.1109/PEAC.2014.7037873","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037873","url":null,"abstract":"The paper presents a gate driver for current-control power semiconductor devices such as BJT. The gate driver has a capability to reduce switching time duration of a power transistor, both in turn-on and turn-off transients. Besides, when the transistor is in static conduction periods, the driver gives a high driving current to the power transistor with holding up by a low supply voltage. This leads to reduce power losses of the driver and switching losses of the transistor. Then, an efficient switching process happens with the whole power switching unit. The paper provides PSpice simulated switching results using a manufacturer provided 1.2kV SiC BJT model to confirm the feasibility of the proposed driver and compare it with a conventional unipolar driver. The results are in good agreement with the theoretical prediction.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"70 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":"129478868","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.2014.7037893
Xiangdong Sun, Tai Fan, Shao-Liang An, Qi Zhang, Bo Zhang
An improved grid-connected photovoltaic (PV) power generation system is proposed to solve the problem that the total harmonic distortion (THD) of grid-connected current generally exceeds 5% under the condition of low output power of PV array in this paper. The system includes a larger capacity master inverter with an LCL filter and a smaller capacity slave inverter with an L filter. Two inverters are connected in parallel with the utility grid via an isolated line-frequency transformer. Two inverters can operate in one of three working modes according to output power of the PV array to reduce the grid-connected harmonic current in full power ranges. Moreover, an active harmonic compensation circuit and its control method are presented to eliminate the harmonic current generated by the inverter. Design process of the system is studied. Control strategies of the different working modes are discussed. Simulation results verify that the system and its control strategies are feasible.
{"title":"An improved grid-connected photovoltaic power generation system with low harmonic current in full power ranges","authors":"Xiangdong Sun, Tai Fan, Shao-Liang An, Qi Zhang, Bo Zhang","doi":"10.1109/PEAC.2014.7037893","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037893","url":null,"abstract":"An improved grid-connected photovoltaic (PV) power generation system is proposed to solve the problem that the total harmonic distortion (THD) of grid-connected current generally exceeds 5% under the condition of low output power of PV array in this paper. The system includes a larger capacity master inverter with an LCL filter and a smaller capacity slave inverter with an L filter. Two inverters are connected in parallel with the utility grid via an isolated line-frequency transformer. Two inverters can operate in one of three working modes according to output power of the PV array to reduce the grid-connected harmonic current in full power ranges. Moreover, an active harmonic compensation circuit and its control method are presented to eliminate the harmonic current generated by the inverter. Design process of the system is studied. Control strategies of the different working modes are discussed. Simulation results verify that the system and its control strategies are feasible.","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":"129803929","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.2014.7037933
Yingqi Zhang
For grid-tied inverters, islanding occurs when the grid is disconnected but the inverters are still energizing the local loads. When the inverter output active and reactive power match the local loads, the inverter output voltage and frequency will keep the same values as before. Islanding poses a hazard to maintenance workers and equipment. To detect islanding, a disturbance signal is usually added to the reference of the inverter output real power or reactive power with positive feedback manner. If the inverter output voltage or inverter output frequency is driven outside of the normal range, islanding is detected and the inverter will be de-energized. A parallel RLC load is widely used to verify effectiveness of anti-islanding detection. In this paper, transfer functions of anti-islanding loop gain are derived. These transfer functions are used to design anti-islanding control loop. Time domain simulation results are also included.
{"title":"Anti-islanding modeling of grid-tied inverters","authors":"Yingqi Zhang","doi":"10.1109/PEAC.2014.7037933","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037933","url":null,"abstract":"For grid-tied inverters, islanding occurs when the grid is disconnected but the inverters are still energizing the local loads. When the inverter output active and reactive power match the local loads, the inverter output voltage and frequency will keep the same values as before. Islanding poses a hazard to maintenance workers and equipment. To detect islanding, a disturbance signal is usually added to the reference of the inverter output real power or reactive power with positive feedback manner. If the inverter output voltage or inverter output frequency is driven outside of the normal range, islanding is detected and the inverter will be de-energized. A parallel RLC load is widely used to verify effectiveness of anti-islanding detection. In this paper, transfer functions of anti-islanding loop gain are derived. These transfer functions are used to design anti-islanding control loop. Time domain simulation results are also included.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"51 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":"114361749","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.2014.7038095
Khiem Nguyen-Duy, A. Knott, Michael A. E. Andersen
This paper presents the loss performance analysis of an isolated power supply that is designed for ultra-fast tracking converters. The results of the analysis provide insights into the operation of the proposed power supply, how each physical component contributes to the total loss, and how its efficiency may be further improved.
{"title":"Loss performance analysis of an isolated power supply for ultrafast tracking converters","authors":"Khiem Nguyen-Duy, A. Knott, Michael A. E. Andersen","doi":"10.1109/PEAC.2014.7038095","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038095","url":null,"abstract":"This paper presents the loss performance analysis of an isolated power supply that is designed for ultra-fast tracking converters. The results of the analysis provide insights into the operation of the proposed power supply, how each physical component contributes to the total loss, and how its efficiency may be further improved.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"208 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":"114841644","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.2014.7038072
Yuya Maeyama, H. Omori, N. Kimura, T. Morizane, M. Nakaoka
AC motor-driven electric scooter in addition to mini-EV which are highly eco-efficient, high performance, more convenient, and air-pollution free are to offer a certain powerful solution to global environmental problem. This paper presents a newly-developed super-quick charging power electric motor-driven scooter (Electric Scooter) incorporating EDLC stack useful for a low carbon society. Described is a practical design criteria and method of the EDLC stack-based electric scooter with a ZCS-DC/DC high frequency link converter and a running operation performance in experiment. Furthermore, a pulse power EDLC stack charging equipment is proposed from a practical viewpoint.
{"title":"A novel type of ultracapacitor electric scooter with EDLC super rapid charging system for home use","authors":"Yuya Maeyama, H. Omori, N. Kimura, T. Morizane, M. Nakaoka","doi":"10.1109/PEAC.2014.7038072","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038072","url":null,"abstract":"AC motor-driven electric scooter in addition to mini-EV which are highly eco-efficient, high performance, more convenient, and air-pollution free are to offer a certain powerful solution to global environmental problem. This paper presents a newly-developed super-quick charging power electric motor-driven scooter (Electric Scooter) incorporating EDLC stack useful for a low carbon society. Described is a practical design criteria and method of the EDLC stack-based electric scooter with a ZCS-DC/DC high frequency link converter and a running operation performance in experiment. Furthermore, a pulse power EDLC stack charging equipment is proposed from a practical viewpoint.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"4 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":"114658302","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.2014.7038064
Yixuan Guo, B. Gao, Xiaoling Yu, Kangping Wang, Xu Yang
In this paper, a new GaN-based integrated module is designed to solve the problems encountered in the application of GaN devices, such as large parasitic inductance and thermal management problems. The layout of the integrated module is optimized to reduce the parasitic inductance. At the same time, different kinds of substrates are compared and the size of integrated module is studied. Finally, simulation and experiment results show that the layout has a small parasitic inductance of about 0.22nH as well as a good heat transfer performance. Thermal simulation results are very close to experimental results. Besides, simulation results show that heat radiation must be considered in the thermal model because it accounts for a large proportion under natural convection.
{"title":"Design and heat transfer research of GaN-based integrated module","authors":"Yixuan Guo, B. Gao, Xiaoling Yu, Kangping Wang, Xu Yang","doi":"10.1109/PEAC.2014.7038064","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038064","url":null,"abstract":"In this paper, a new GaN-based integrated module is designed to solve the problems encountered in the application of GaN devices, such as large parasitic inductance and thermal management problems. The layout of the integrated module is optimized to reduce the parasitic inductance. At the same time, different kinds of substrates are compared and the size of integrated module is studied. Finally, simulation and experiment results show that the layout has a small parasitic inductance of about 0.22nH as well as a good heat transfer performance. Thermal simulation results are very close to experimental results. Besides, simulation results show that heat radiation must be considered in the thermal model because it accounts for a large proportion under natural convection.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"24 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":"132041895","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.2014.7037906
Ruiqi Li, H. Geng, Geng Yang
For grid-connected renewable energy equipment, asymmetrical high voltage swell threatens the grid-side converter (GSC) and the dc-link capacitor. Asymmetrical high voltage swell may cause significant fluctuations across the dc-link voltage, and energy reflux of the GSC, even result in the runaway of the GSC. To cope with this situation, the control strategy of the GSC has to be improved. Firstly, the controllability of the GSC is analyzed considering the asymmetrical high voltage swell situation and the converter power rating. Afterwards, an asymmetrical high voltage ride through (HVRT) control strategy is proposed by considering the reactive current compensation and the dc-link voltage fluctuations, which needs to raise the dc-link voltage in certain cases. However, increasing the dc-link voltage sometimes is not practical for the rating of the physical devices and the product cost. Therefore, the asymmetrical HVRT grid code has to be formulated carefully considering the operation capability of the GSC. The simulation experiments verified that the GSC can be controllable and the dc-link voltage is stable.
{"title":"Asymmetrical high voltage ride through control strategy of grid-side converter for grid-connected renewable energy equipment","authors":"Ruiqi Li, H. Geng, Geng Yang","doi":"10.1109/PEAC.2014.7037906","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037906","url":null,"abstract":"For grid-connected renewable energy equipment, asymmetrical high voltage swell threatens the grid-side converter (GSC) and the dc-link capacitor. Asymmetrical high voltage swell may cause significant fluctuations across the dc-link voltage, and energy reflux of the GSC, even result in the runaway of the GSC. To cope with this situation, the control strategy of the GSC has to be improved. Firstly, the controllability of the GSC is analyzed considering the asymmetrical high voltage swell situation and the converter power rating. Afterwards, an asymmetrical high voltage ride through (HVRT) control strategy is proposed by considering the reactive current compensation and the dc-link voltage fluctuations, which needs to raise the dc-link voltage in certain cases. However, increasing the dc-link voltage sometimes is not practical for the rating of the physical devices and the product cost. Therefore, the asymmetrical HVRT grid code has to be formulated carefully considering the operation capability of the GSC. The simulation experiments verified that the GSC can be controllable and the dc-link voltage is stable.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"57 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":"132109750","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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