Pub Date : 1999-07-27DOI: 10.1109/PEDS.1999.792859
M. Yamamoto, M. Yoshida, T. Honda, H. Iwamoto, E. Hiraki, S. Sugimoto, I. Kouno, M. Nakaoka
This paper presents feasible performance of a digitally-controlled three-level three-phase voltage source-type soft-switching inverter with two auxiliary resonant DC link snubbers which can operate under conditions of zero voltage switching (ZVS). The operating principle of this inverter topology suitable for high power energy storage utilization system is discussed as compared with the two-level soft switching inverter. The system effectiveness of the new inverter treated here is proved on the basis of experimental results.
{"title":"Feasible performance evaluations of 3-level 3-phase voltage source soft-switching inverter using IGBT modules","authors":"M. Yamamoto, M. Yoshida, T. Honda, H. Iwamoto, E. Hiraki, S. Sugimoto, I. Kouno, M. Nakaoka","doi":"10.1109/PEDS.1999.792859","DOIUrl":"https://doi.org/10.1109/PEDS.1999.792859","url":null,"abstract":"This paper presents feasible performance of a digitally-controlled three-level three-phase voltage source-type soft-switching inverter with two auxiliary resonant DC link snubbers which can operate under conditions of zero voltage switching (ZVS). The operating principle of this inverter topology suitable for high power energy storage utilization system is discussed as compared with the two-level soft switching inverter. The system effectiveness of the new inverter treated here is proved on the basis of experimental results.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128708539","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 : 1999-07-27DOI: 10.1109/PEDS.1999.794564
Jianping Xu, Xiaohong Cao, Qianchao Luo
An improved two-transistor forward converter, an active damp two-transistor forward converter, has been proposed in this paper. It is developed by paralleling an active damp circuit at the primary side of the transformer of the two-transistor forward converter to damp the voltage across power switches, to demagnetize the transformer and to achieve zero-voltage-turn-on of the power switches. Complete analysis and simulation of the converter are performed, from which some important results are obtained and given.
{"title":"An improved two-transistor forward converter","authors":"Jianping Xu, Xiaohong Cao, Qianchao Luo","doi":"10.1109/PEDS.1999.794564","DOIUrl":"https://doi.org/10.1109/PEDS.1999.794564","url":null,"abstract":"An improved two-transistor forward converter, an active damp two-transistor forward converter, has been proposed in this paper. It is developed by paralleling an active damp circuit at the primary side of the transformer of the two-transistor forward converter to damp the voltage across power switches, to demagnetize the transformer and to achieve zero-voltage-turn-on of the power switches. Complete analysis and simulation of the converter are performed, from which some important results are obtained and given.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116768899","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 : 1999-07-27DOI: 10.1109/PEDS.1999.792729
Wu Xin, N. Poon, C. Lee, M. Pong, Z. Qian
Common mode noise current is a major source of EMI in switching mode power supplies. The generation mechanism is studied from a current balancing point of view in this paper. A proper understanding of common mode noise provides a systematic approach to solve common mode interference in SMPS. Impedance balance and noise source balance analysis of a boost converter are presented. Simulation and experiment results are shown to verify this concept.
{"title":"A study of common mode noise in switching power supply from a current balancing viewpoint","authors":"Wu Xin, N. Poon, C. Lee, M. Pong, Z. Qian","doi":"10.1109/PEDS.1999.792729","DOIUrl":"https://doi.org/10.1109/PEDS.1999.792729","url":null,"abstract":"Common mode noise current is a major source of EMI in switching mode power supplies. The generation mechanism is studied from a current balancing point of view in this paper. A proper understanding of common mode noise provides a systematic approach to solve common mode interference in SMPS. Impedance balance and noise source balance analysis of a boost converter are presented. Simulation and experiment results are shown to verify this concept.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128057939","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 : 1999-07-27DOI: 10.1109/PEDS.1999.792821
Wan-Ki Min, Joon-ki Min, Jae-Ho Choi
This paper proposes the novel control scheme of a static synchronous compensator (STATCOM) with cascade multilevel inverter which employs an H-bridge inverter (HBI). The STATCOM system is modeled using the D-Q transform which calculates the instantaneous reactive power. This model is used to design a control strategy based on the control of the phase angle of the fundamental switching pattern. This switching method produces the staircase type waveform in a cascade multilevel inverter. The selective harmonic elimination (SHE) allows keeping the total harmonic distortion (THD) low in the output voltage of the inverter. The switching pattern is used as a programmed switching pattern stored in an EPROM. A rotated switching scheme of fundamental frequency is switched to be on and off equally for each device and applied to control the DC voltage balancing. As a result, it makes the DC voltage of STATCOM balance and the control response fast to the step change of reactive power.
{"title":"Control of STATCOM using cascade multilevel inverter for high power application","authors":"Wan-Ki Min, Joon-ki Min, Jae-Ho Choi","doi":"10.1109/PEDS.1999.792821","DOIUrl":"https://doi.org/10.1109/PEDS.1999.792821","url":null,"abstract":"This paper proposes the novel control scheme of a static synchronous compensator (STATCOM) with cascade multilevel inverter which employs an H-bridge inverter (HBI). The STATCOM system is modeled using the D-Q transform which calculates the instantaneous reactive power. This model is used to design a control strategy based on the control of the phase angle of the fundamental switching pattern. This switching method produces the staircase type waveform in a cascade multilevel inverter. The selective harmonic elimination (SHE) allows keeping the total harmonic distortion (THD) low in the output voltage of the inverter. The switching pattern is used as a programmed switching pattern stored in an EPROM. A rotated switching scheme of fundamental frequency is switched to be on and off equally for each device and applied to control the DC voltage balancing. As a result, it makes the DC voltage of STATCOM balance and the control response fast to the step change of reactive power.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128156076","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 : 1999-07-27DOI: 10.1109/PEDS.1999.794559
K.H. Yuen, Zhuolin Ye, M. Pong, W. Lo
In this paper, a statistical method to model harmonic currents of a train in a traction power-supply system is presented. Measurements on a train running normally according to a schedule was performed to establish probability density functions (p.d.f.) of fundamental and harmonic currents. The results are given in a statistical viewpoint. A statistical method is used to evaluate harmonics which gives more practical results than the worst case method. The most important information detained is whether the probability of harmonic currents exceed the acceptable level of harmonics. This train model so established forms the basis of a complete electrical traction system model.
{"title":"Modeling of traction harmonic current using statistical method","authors":"K.H. Yuen, Zhuolin Ye, M. Pong, W. Lo","doi":"10.1109/PEDS.1999.794559","DOIUrl":"https://doi.org/10.1109/PEDS.1999.794559","url":null,"abstract":"In this paper, a statistical method to model harmonic currents of a train in a traction power-supply system is presented. Measurements on a train running normally according to a schedule was performed to establish probability density functions (p.d.f.) of fundamental and harmonic currents. The results are given in a statistical viewpoint. A statistical method is used to evaluate harmonics which gives more practical results than the worst case method. The most important information detained is whether the probability of harmonic currents exceed the acceptable level of harmonics. This train model so established forms the basis of a complete electrical traction system model.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126049700","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 : 1999-07-27DOI: 10.1109/PEDS.1999.792769
Jiann-Fuh Chen, L. Chiang, C. Chu, Yong Lung Lee, T. Liang
A single-stage single-phase three-wire(1/spl phi/3W) photovoltaic energy conversion system connected with a utility power system is presented in this paper. The DC power generated by the solar cells was converted into AC power by a 1/spl phi/3w inverter with an auxiliary LC filter and was fed directly to the utility line. Since the output characteristics of the solar cells were highly affected by the environment and lumen of Sun, the PV energy conversion system was adapted to track the maximum power operation point. The size and weight of the PV conversion system can be largely reduced without energy storage devices, DC to DC converter, and center-tapped transformer. Finally, a 1 kW experimental prototype was built to demonstrate the performance of the proposed technique.
介绍了一种与公用电力系统连接的单级单相三线(1/spl phi/3W)光伏能量转换系统。太阳能电池产生的直流电通过带有辅助LC滤波器的1/spl phi/3w逆变器转换成交流电，并直接馈送到公用线路。由于太阳能电池的输出特性受环境和太阳流明的影响较大，因此采用光伏能量转换系统跟踪最大功率工作点。无需储能装置、DC - to - DC变换器和中心抽头变压器，光伏转换系统的体积和重量可以大大减小。最后，建立了一个1千瓦的实验样机来验证所提出的技术的性能。
{"title":"Study and implementation of the single-phase three-wire photovoltaic energy conversion system","authors":"Jiann-Fuh Chen, L. Chiang, C. Chu, Yong Lung Lee, T. Liang","doi":"10.1109/PEDS.1999.792769","DOIUrl":"https://doi.org/10.1109/PEDS.1999.792769","url":null,"abstract":"A single-stage single-phase three-wire(1/spl phi/3W) photovoltaic energy conversion system connected with a utility power system is presented in this paper. The DC power generated by the solar cells was converted into AC power by a 1/spl phi/3w inverter with an auxiliary LC filter and was fed directly to the utility line. Since the output characteristics of the solar cells were highly affected by the environment and lumen of Sun, the PV energy conversion system was adapted to track the maximum power operation point. The size and weight of the PV conversion system can be largely reduced without energy storage devices, DC to DC converter, and center-tapped transformer. Finally, a 1 kW experimental prototype was built to demonstrate the performance of the proposed technique.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122278704","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 : 1999-07-27DOI: 10.1109/PEDS.1999.794595
J. Gho, Y. Chae, K. Kim, K. S. Won, H. Mok, G. Choe
In the conventional wire feeder drives of the welding machine, most controllers have a simple speed control loop. The circuit topology of a wire feeder drive is composed of the diode rectifier and one switching device like a MOSFET or thyristor. Because they have no torque control loop, their speed is not regular in the welding processing. For complete speed control of wire feeding speed, the control loop must consist of a torque control loop and a speed control loop. Therefore the conventional wire feeder drive has bad response for sudden disturbance like arc pressure. It can affect some welding performance such as spatter generation and irregular bead forming. Welding performance using a full-bridge PWM speed control scheme was compared with conventional driving scheme and made an experiment in this paper. The result confirms the possibility of welding performance improvement by proposed constant speed control scheme in the experiment.
{"title":"A study on the effect of wire feeding speed controller in inverter arc welding machine","authors":"J. Gho, Y. Chae, K. Kim, K. S. Won, H. Mok, G. Choe","doi":"10.1109/PEDS.1999.794595","DOIUrl":"https://doi.org/10.1109/PEDS.1999.794595","url":null,"abstract":"In the conventional wire feeder drives of the welding machine, most controllers have a simple speed control loop. The circuit topology of a wire feeder drive is composed of the diode rectifier and one switching device like a MOSFET or thyristor. Because they have no torque control loop, their speed is not regular in the welding processing. For complete speed control of wire feeding speed, the control loop must consist of a torque control loop and a speed control loop. Therefore the conventional wire feeder drive has bad response for sudden disturbance like arc pressure. It can affect some welding performance such as spatter generation and irregular bead forming. Welding performance using a full-bridge PWM speed control scheme was compared with conventional driving scheme and made an experiment in this paper. The result confirms the possibility of welding performance improvement by proposed constant speed control scheme in the experiment.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"7 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131798466","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 : 1999-07-27DOI: 10.1109/PEDS.1999.794532
S. Azzopardi, J. Vinassa, C. Zardini
In this paper, we investigate the behavior of 1200 V punch-through (PT) and nonpunch-through (NPT) IGBTs under unclamped inductive switching (UIS) stress at various temperature and peak collector current values. UIS conditions, occurring when the freewheeling diode in parallel to the load has failed, submit the device to high voltage and high current simultaneously. The results show that 1200 V NPT-IGBTs, which did not fail in these experiments, present a higher ruggedness than 1200 V PT-IGBTs. Generally, NPT-IGBTs are more sensitive to the peak collector current variation than to the temperature. Furthermore, the dynamic breakdown voltage value is equal to the static breakdown voltage during the avalanche mode. As for the PT-IGBTs, their behaviour depends strongly on the temperature and also on the peak collector current values. More precisely, the dynamic breakdown voltage value is reduced and is considerable depending on the test conditions. This reduction is due to an excess of positive charges in the drift region which does not allow the expansion of the electric field. This phenomenon is emphasized when the temperature rises.
在本文中，我们研究了在不同温度和集电极峰值电流值下，1200 V穿通(PT)和非穿通(NPT) igbt在非箝位电感开关(UIS)应力下的行为。当与负载并联的自由转动二极管失效时，将设备同时置于高压和大电流下。结果表明，与1200 V pt - igbt相比，1200 V npt - igbt在这些实验中没有失效，具有更高的坚固性。一般来说，npt - igbt对峰值集电极电流的变化比对温度的变化更敏感。在雪崩模式下，动态击穿电压值与静态击穿电压值相等。至于pt - igbt，它们的行为在很大程度上取决于温度和集电极的峰值电流值。更准确地说，动态击穿电压值被降低，并且根据测试条件是相当大的。这种减少是由于在漂移区过量的正电荷，不允许扩大电场。当温度升高时，这种现象更加突出。
{"title":"Performances of 1200 V punch-through and nonpunch-through IGBTs under unclamped inductive switching","authors":"S. Azzopardi, J. Vinassa, C. Zardini","doi":"10.1109/PEDS.1999.794532","DOIUrl":"https://doi.org/10.1109/PEDS.1999.794532","url":null,"abstract":"In this paper, we investigate the behavior of 1200 V punch-through (PT) and nonpunch-through (NPT) IGBTs under unclamped inductive switching (UIS) stress at various temperature and peak collector current values. UIS conditions, occurring when the freewheeling diode in parallel to the load has failed, submit the device to high voltage and high current simultaneously. The results show that 1200 V NPT-IGBTs, which did not fail in these experiments, present a higher ruggedness than 1200 V PT-IGBTs. Generally, NPT-IGBTs are more sensitive to the peak collector current variation than to the temperature. Furthermore, the dynamic breakdown voltage value is equal to the static breakdown voltage during the avalanche mode. As for the PT-IGBTs, their behaviour depends strongly on the temperature and also on the peak collector current values. More precisely, the dynamic breakdown voltage value is reduced and is considerable depending on the test conditions. This reduction is due to an excess of positive charges in the drift region which does not allow the expansion of the electric field. This phenomenon is emphasized when the temperature rises.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124813005","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 : 1999-07-27DOI: 10.1109/PEDS.1999.792795
C. Choi, C.K. Li, S. Kok
With the trend of miniaturization in electronic products, the power supply is one of the major components that needs to be reduced in size. Reduction in the size of power supplies can be achieved by a topology change from linear transformer type to switching mode. To reduce the size further, the switching frequency has to be increased. However, there are a number of limitations and problems associated with the increase of switching frequency. The active-clamp discontinuous mode flyback converter (ADCMFC) introduced in this paper is one of the solutions to increase the switching frequency. Besides, the paper also introduces an optimization method to obtain the transfer function of the ADCMFC under different operating conditions.
{"title":"Modeling of an active clamp discontinuous conduction mode flyback converter under variation of operating conditions","authors":"C. Choi, C.K. Li, S. Kok","doi":"10.1109/PEDS.1999.792795","DOIUrl":"https://doi.org/10.1109/PEDS.1999.792795","url":null,"abstract":"With the trend of miniaturization in electronic products, the power supply is one of the major components that needs to be reduced in size. Reduction in the size of power supplies can be achieved by a topology change from linear transformer type to switching mode. To reduce the size further, the switching frequency has to be increased. However, there are a number of limitations and problems associated with the increase of switching frequency. The active-clamp discontinuous mode flyback converter (ADCMFC) introduced in this paper is one of the solutions to increase the switching frequency. Besides, the paper also introduces an optimization method to obtain the transfer function of the ADCMFC under different operating conditions.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117129604","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 : 1999-07-27DOI: 10.1109/PEDS.1999.794620
D. Sutanto, L. Snider, K. Mok
An alternative control strategy of a STATCOM, based on hysteresis current control of the switches is presented. It is shown that a STATCOM under hysteresis current control will have nearly sinusoidal output current for reactive power compensation while keeping the STATCOM in its simplest configuration. The proposed device was simulated using ATP-EMTP, and the results demonstrate the advantages of hysteresis control.
{"title":"EMTP simulation of a STATCOM using hysteresis current control","authors":"D. Sutanto, L. Snider, K. Mok","doi":"10.1109/PEDS.1999.794620","DOIUrl":"https://doi.org/10.1109/PEDS.1999.794620","url":null,"abstract":"An alternative control strategy of a STATCOM, based on hysteresis current control of the switches is presented. It is shown that a STATCOM under hysteresis current control will have nearly sinusoidal output current for reactive power compensation while keeping the STATCOM in its simplest configuration. The proposed device was simulated using ATP-EMTP, and the results demonstrate the advantages of hysteresis control.","PeriodicalId":254764,"journal":{"name":"Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124135690","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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