Pub Date : 2003-06-15DOI: 10.1109/PESC.2003.1217702
Q. Yu, R. Nelms
In a UPS, the output voltage of a single-phase inverter is filtered with an LC filter to provide a sinusoidal output voltage. Since this inverter has an inductive load like an inverter for a motor drive, topologies for ZVS inverters utilized for motor drives can also be applied in the UPS application. A single-phase resonant snubber inverter (RSI) for application in a UPS has been developed. Analysis of the RSI in a normalized state plane provided insight into the operation of this ZVS inverter. Based on this analysis, fixed timing control based on the direction of the current flowing through the inductor in the output filter was implemented to control the auxiliary switches in a prototype RSI. The direction of the inductor current was sensed using a secondary winding on the output filter inductor. Experimental results are provided for a 1 kW prototype RSI in a UPS.
{"title":"A single-phase resonant snubber inverter with fixed timing control for a UPS","authors":"Q. Yu, R. Nelms","doi":"10.1109/PESC.2003.1217702","DOIUrl":"https://doi.org/10.1109/PESC.2003.1217702","url":null,"abstract":"In a UPS, the output voltage of a single-phase inverter is filtered with an LC filter to provide a sinusoidal output voltage. Since this inverter has an inductive load like an inverter for a motor drive, topologies for ZVS inverters utilized for motor drives can also be applied in the UPS application. A single-phase resonant snubber inverter (RSI) for application in a UPS has been developed. Analysis of the RSI in a normalized state plane provided insight into the operation of this ZVS inverter. Based on this analysis, fixed timing control based on the direction of the current flowing through the inductor in the output filter was implemented to control the auxiliary switches in a prototype RSI. The direction of the inductor current was sensed using a secondary winding on the output filter inductor. Experimental results are provided for a 1 kW prototype RSI in a UPS.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124127609","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218296
O. Ojo, P. Kshirsagar
A new carrier-based discontinuous pulse-width modulation (PWM) scheme anchored on a novel space vector modulation methodology is proposed in this paper for four-leg converters. Using a space vector definition that includes the zero sequence voltage component and partitioning the feasible sixteen modes into three separate sets, the expressions for the modulation signals for the discontinuous carrier based PWM scheme are set forth. Significantly, the switching devices can be clamped either to the positive or negative rail for 120 degrees under all operating conditions of unbalanced three-phase voltages; ensuring the reduction of switching losses and the effective switching frequency of the inverters. The discontinuous PWM modulation methodology proposed which is shown by experimental results to synthesise desirable balanced or unbalanced three-phase voltage sets complements and further clarifies the results of the 3-dimensional space vector modulation scheme (3-D SVM) for four-leg converters reported in the literature.
{"title":"A new carrier-based discontinuous PWM modulation methodology for four-leg voltage source inverters","authors":"O. Ojo, P. Kshirsagar","doi":"10.1109/PESC.2003.1218296","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218296","url":null,"abstract":"A new carrier-based discontinuous pulse-width modulation (PWM) scheme anchored on a novel space vector modulation methodology is proposed in this paper for four-leg converters. Using a space vector definition that includes the zero sequence voltage component and partitioning the feasible sixteen modes into three separate sets, the expressions for the modulation signals for the discontinuous carrier based PWM scheme are set forth. Significantly, the switching devices can be clamped either to the positive or negative rail for 120 degrees under all operating conditions of unbalanced three-phase voltages; ensuring the reduction of switching losses and the effective switching frequency of the inverters. The discontinuous PWM modulation methodology proposed which is shown by experimental results to synthesise desirable balanced or unbalanced three-phase voltage sets complements and further clarifies the results of the 3-dimensional space vector modulation scheme (3-D SVM) for four-leg converters reported in the literature.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130612242","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218151
T. Brekken, N. Mohan
Wind energy is often installed in rural, remote areas characterized by weak, unbalanced power transmission grids. In induction wind generators, unbalanced three phase stator voltages cause a number of problems, including overheating and stress on the mechanical components from torque pulsations. Therefore, beyond a certain amount of unbalance (for example 6%), induction wind generators are switched out of the network. In doubly-fed induction generators, control of rotor currents allows for adjustable speed operation and reactive power control. In addition, it is possible to control the rotor currents to correct for the problems caused by unbalanced stator voltages. This paper presents a novel controller design for a doubly-fed induction generator that provides adjustable speed and reactive power control while greatly reducing torque pulsations.
{"title":"A novel doubly-fed induction wind generator control scheme for reactive power control and torque pulsation compensation under unbalanced grid voltage conditions","authors":"T. Brekken, N. Mohan","doi":"10.1109/PESC.2003.1218151","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218151","url":null,"abstract":"Wind energy is often installed in rural, remote areas characterized by weak, unbalanced power transmission grids. In induction wind generators, unbalanced three phase stator voltages cause a number of problems, including overheating and stress on the mechanical components from torque pulsations. Therefore, beyond a certain amount of unbalance (for example 6%), induction wind generators are switched out of the network. In doubly-fed induction generators, control of rotor currents allows for adjustable speed operation and reactive power control. In addition, it is possible to control the rotor currents to correct for the problems caused by unbalanced stator voltages. This paper presents a novel controller design for a doubly-fed induction generator that provides adjustable speed and reactive power control while greatly reducing torque pulsations.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130497810","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 : 2003-06-15DOI: 10.1109/PESC.2003.1217754
H. Cha, P. Enjeti
In this paper, a new three-phase high-frequency link matrix converter is discussed and the topology of conventional matrix converter is modified with the addition of a transformer for a variable speed constant frequency (VSCF) application. The proposed approach accomplishes voltage transfer ratio more than unity, galvanic isolation between both voltage sources and higher power density by employing a high-frequency transformer into the intermediate stage of the dual bridge matrix converter. It has a bidirectional power flow capability, controllable displacement power factor and lower harmonic distortion at both variable speed source and fixed frequency utility. Further, asynchronous or synchronous PWM can be employed depending on the frequency modulation ratio in the primary side converter and it guarantees full input voltage utilization for DC-link and near symmetric square wave pulse trains applied to high frequency transformer regardless of varying input frequency. The proposed approach is a competitive solution for VSCF distributed generating application such as wind-turbine and micro-turbine application. Simulation results are shown to demonstrate the advantages of the proposed system. Experimental results on a 230V, 3kVA 400 Hz to 60 Hz VSCF system based on DSP controller are presented.
{"title":"A three-phase AC/AC high-frequency link matrix converter for VSCF applications","authors":"H. Cha, P. Enjeti","doi":"10.1109/PESC.2003.1217754","DOIUrl":"https://doi.org/10.1109/PESC.2003.1217754","url":null,"abstract":"In this paper, a new three-phase high-frequency link matrix converter is discussed and the topology of conventional matrix converter is modified with the addition of a transformer for a variable speed constant frequency (VSCF) application. The proposed approach accomplishes voltage transfer ratio more than unity, galvanic isolation between both voltage sources and higher power density by employing a high-frequency transformer into the intermediate stage of the dual bridge matrix converter. It has a bidirectional power flow capability, controllable displacement power factor and lower harmonic distortion at both variable speed source and fixed frequency utility. Further, asynchronous or synchronous PWM can be employed depending on the frequency modulation ratio in the primary side converter and it guarantees full input voltage utilization for DC-link and near symmetric square wave pulse trains applied to high frequency transformer regardless of varying input frequency. The proposed approach is a competitive solution for VSCF distributed generating application such as wind-turbine and micro-turbine application. Simulation results are shown to demonstrate the advantages of the proposed system. Experimental results on a 230V, 3kVA 400 Hz to 60 Hz VSCF system based on DSP controller are presented.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129654765","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218152
Zhe Chen, F. Blaabjerg, J. Pedersen
This paper presents a hybrid compensation system consisting of an active filter and distributed passive filters. In the system, each individual passive filter connected to a distortion source is designed to eliminate main harmonics and supply reactive power for the distortion source, while the active filter is responsible for the correction of the system unbalance and the cancellation of the remaining harmonics. The studies are presented for a power system including dispersed generation units connected into systems through power electronic converters and diode rectifier loads, which generate distorted waveforms. The simulation results have demonstrated that good compensation effects can be achieved by using the combined filter system including distributed passive filters and an active filter.
{"title":"A hybrid compensation system with an active filter and distributed passive filters in power systems with dispersed generation","authors":"Zhe Chen, F. Blaabjerg, J. Pedersen","doi":"10.1109/PESC.2003.1218152","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218152","url":null,"abstract":"This paper presents a hybrid compensation system consisting of an active filter and distributed passive filters. In the system, each individual passive filter connected to a distortion source is designed to eliminate main harmonics and supply reactive power for the distortion source, while the active filter is responsible for the correction of the system unbalance and the cancellation of the remaining harmonics. The studies are presented for a power system including dispersed generation units connected into systems through power electronic converters and diode rectifier loads, which generate distorted waveforms. The simulation results have demonstrated that good compensation effects can be achieved by using the combined filter system including distributed passive filters and an active filter.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126049860","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 : 2003-06-15DOI: 10.1109/PESC.2003.1216593
R. Griñó, R. Costa-Castelló, E. Fossas
Shunt active power filters are proved a useful elements to correct the distorted currents caused by nonlinear loads in power distribution systems. This work presents an all digital approach, based on the repetitive control technique, for their control and a design is performed for the particular case of single-phase shunt active filters with a full-bridge boost topology. Several experimental results are also presented to show the behavior of the closed loop system.
{"title":"Digital control of a single-phase shunt active filter","authors":"R. Griñó, R. Costa-Castelló, E. Fossas","doi":"10.1109/PESC.2003.1216593","DOIUrl":"https://doi.org/10.1109/PESC.2003.1216593","url":null,"abstract":"Shunt active power filters are proved a useful elements to correct the distorted currents caused by nonlinear loads in power distribution systems. This work presents an all digital approach, based on the repetitive control technique, for their control and a design is performed for the particular case of single-phase shunt active filters with a full-bridge boost topology. Several experimental results are also presented to show the behavior of the closed loop system.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126333797","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218157
V. Cárdenas, L. Morán, A. Bahamondes, J. Dixon
This paper presents a comparison of three different techniques used for the generation of the current reference signal in shunt active power filters. The three different techniques are evaluated and compared in terms of compensation performance under steady state and transient operating conditions, implementations requirements, and compensation in four wire power distribution systems, with unbalanced single phase nonlinear loads. The three techniques analyzed are the instantaneous reactive power theory (PQ theory), the synchronous reference frame theory (SRF) and peak detection method (PDM). The technical evaluation is done by considering the robustness for the operation with unbalanced and distorted supply voltages, unbalanced load currents, control signals conditioning and processing delays introduced by the implementation with a DSP. The comparison is based on theoretical analysis and simulated results obtained with Matlab. The principal conclusion is that the compensation performance of the different techniques is similar under ideal conditions, but under the presence of unbalanced and voltage distortion, the compensation performance is quite different, and not all the reference methods allows full compensation. The synchronous reference frame algorithm presents the best performance for different operating conditions.
{"title":"Comparative analysis of real time reference generation techniques for four-wire shunt active power filters","authors":"V. Cárdenas, L. Morán, A. Bahamondes, J. Dixon","doi":"10.1109/PESC.2003.1218157","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218157","url":null,"abstract":"This paper presents a comparison of three different techniques used for the generation of the current reference signal in shunt active power filters. The three different techniques are evaluated and compared in terms of compensation performance under steady state and transient operating conditions, implementations requirements, and compensation in four wire power distribution systems, with unbalanced single phase nonlinear loads. The three techniques analyzed are the instantaneous reactive power theory (PQ theory), the synchronous reference frame theory (SRF) and peak detection method (PDM). The technical evaluation is done by considering the robustness for the operation with unbalanced and distorted supply voltages, unbalanced load currents, control signals conditioning and processing delays introduced by the implementation with a DSP. The comparison is based on theoretical analysis and simulated results obtained with Matlab. The principal conclusion is that the compensation performance of the different techniques is similar under ideal conditions, but under the presence of unbalanced and voltage distortion, the compensation performance is quite different, and not all the reference methods allows full compensation. The synchronous reference frame algorithm presents the best performance for different operating conditions.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126371316","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218281
S. Lentijo, A. Monti, E. Santi, C. Welch, R. Dougal
Digital control systems require sophisticated testing procedures before final implementation. Various procedures for rapid prototyping have been proposed. However, in many cases they focus on implementation into platforms that are different from the final target. In this paper, we focus on a testing procedure for micro-controller-based control where the real final target is adopted for software testing. The test is performed without real-time constraint so that it can be performed with conventional hardware available in any office desktop. At the same time, information about real-time execution is extracted, which is a significant advantage over simulation environments.
{"title":"A new testing tool for power electronic digital control","authors":"S. Lentijo, A. Monti, E. Santi, C. Welch, R. Dougal","doi":"10.1109/PESC.2003.1218281","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218281","url":null,"abstract":"Digital control systems require sophisticated testing procedures before final implementation. Various procedures for rapid prototyping have been proposed. However, in many cases they focus on implementation into platforms that are different from the final target. In this paper, we focus on a testing procedure for micro-controller-based control where the real final target is adopted for software testing. The test is performed without real-time constraint so that it can be performed with conventional hardware available in any office desktop. At the same time, information about real-time execution is extracted, which is a significant advantage over simulation environments.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121854590","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218319
R. Surend, N. Mohan, R. Ayyanar, R. Button
A hybrid phase modulated converter (HPMC) with current doubler rectification has superior soft switching characteristics, high efficiency, and low EMI as compared to a conventional phase modulated converter. It has essentially three modes of operation: (i) continuous conduction mode (CCM); (ii) continuous conduction mode with reversed inductor currents; and (iii) discontinuous conduction mode (DCM). There is never a discontinuity in conduction in the inductors and the definition of DCM is different in itself. In this paper, the various modes are defined, analyzed and design equations derived. The analyses are also verified with a 500 W peak current mode controlled prototype model, switched at 100 kHz and the results are presented. The soft switching behavior of the converter in this mode is also studied and is found to be advantageous.
{"title":"Analysis of a hybrid phase modulated converter with a current doubler rectifier in discontinuous conduction mode","authors":"R. Surend, N. Mohan, R. Ayyanar, R. Button","doi":"10.1109/PESC.2003.1218319","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218319","url":null,"abstract":"A hybrid phase modulated converter (HPMC) with current doubler rectification has superior soft switching characteristics, high efficiency, and low EMI as compared to a conventional phase modulated converter. It has essentially three modes of operation: (i) continuous conduction mode (CCM); (ii) continuous conduction mode with reversed inductor currents; and (iii) discontinuous conduction mode (DCM). There is never a discontinuity in conduction in the inductors and the definition of DCM is different in itself. In this paper, the various modes are defined, analyzed and design equations derived. The analyses are also verified with a 500 W peak current mode controlled prototype model, switched at 100 kHz and the results are presented. The soft switching behavior of the converter in this mode is also studied and is found to be advantageous.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122873499","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 : 2003-06-15DOI: 10.1109/PESC.2003.1218127
M. Jinno, Po-Yuan Chen, Kun-chih Lin
An efficient active LC snubber for multi-output converters with flyback synchronous rectifier (SR) is proposed in this paper. The proposed active LC snubber can be used to reset transformer and suppress switching surges. Besides, by storing surge energy in the proposed active LC snubber and then releasing it to the flyback SR, the converter can achieve high efficiency. For a forward converter with flyback SR, 90.8%, the maximum output efficiency, can be achieved. Experimental results also show that the output efficiency of this converter with the proposed active LC snubber is higher than that of active-clamped-based converters.
{"title":"An efficient active LC snubber for multi-output converters with flyback synchronous rectifier","authors":"M. Jinno, Po-Yuan Chen, Kun-chih Lin","doi":"10.1109/PESC.2003.1218127","DOIUrl":"https://doi.org/10.1109/PESC.2003.1218127","url":null,"abstract":"An efficient active LC snubber for multi-output converters with flyback synchronous rectifier (SR) is proposed in this paper. The proposed active LC snubber can be used to reset transformer and suppress switching surges. Besides, by storing surge energy in the proposed active LC snubber and then releasing it to the flyback SR, the converter can achieve high efficiency. For a forward converter with flyback SR, 90.8%, the maximum output efficiency, can be achieved. Experimental results also show that the output efficiency of this converter with the proposed active LC snubber is higher than that of active-clamped-based converters.","PeriodicalId":236199,"journal":{"name":"IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03.","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123426309","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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