Pub Date : 2014-11-24DOI: 10.1109/NAPS.2014.6965375
C. Young, J. Thelen, H. Nehrir
Throughout the years, Montana State University's (MSU's) Energy Conversion Laboratory (ECL) has been a valuable educational asset for students understanding of the basics of electrical power and energy conversion. With increased interest in the deployment of solar photovoltaic (PV) systems, a need for the development of an experiment on solar PV was recognized so that the undergraduate students taking the required course, “Energy Conversion Devices,” become familiar with the characteristics of the solar-electric energy conversion system. This paper presents the design and implementation of a low-cost 50-W solar PV experimental station for in-door use. Students obtain in the laboratory the solar PV panel I-V and P-V characteristics, the effect of tilt angle, light intensity and temperature on the panel characteristics, and the function of a charge controller and battery in providing a desired steady voltage at the output of the system to the extent possible. The system is fully computerized and portable, sitting on a rolling cart. In addition to the above, a brief description of the capabilities of the ECL and the typical experiments undergraduate students perform in the Electrical Engineering department's undergraduate energy conversion course is given.
{"title":"Design and implementation of a low-cost solar photovoltaic experimental station for education enhancement","authors":"C. Young, J. Thelen, H. Nehrir","doi":"10.1109/NAPS.2014.6965375","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965375","url":null,"abstract":"Throughout the years, Montana State University's (MSU's) Energy Conversion Laboratory (ECL) has been a valuable educational asset for students understanding of the basics of electrical power and energy conversion. With increased interest in the deployment of solar photovoltaic (PV) systems, a need for the development of an experiment on solar PV was recognized so that the undergraduate students taking the required course, “Energy Conversion Devices,” become familiar with the characteristics of the solar-electric energy conversion system. This paper presents the design and implementation of a low-cost 50-W solar PV experimental station for in-door use. Students obtain in the laboratory the solar PV panel I-V and P-V characteristics, the effect of tilt angle, light intensity and temperature on the panel characteristics, and the function of a charge controller and battery in providing a desired steady voltage at the output of the system to the extent possible. The system is fully computerized and portable, sitting on a rolling cart. In addition to the above, a brief description of the capabilities of the ECL and the typical experiments undergraduate students perform in the Electrical Engineering department's undergraduate energy conversion course is given.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"420 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115927586","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965369
Haoyu Yuan, F. Li
With the development of phasor measurement units (PMU), real-time voltage stability monitoring techniques using phasor measurements have been widely discussed in the past decade. For various measurement-based techniques, the fundamental idea behind them is to identify the Thevenin equivalents (TE) of the outer system seen from the nodes/areas of interests, and then assess the voltage stability margin based on the equivalent circuits. Therefore, fast and accurate identification of the TE is crucial for such online monitoring applications. Though several identification methods have been proposed claiming to achieve good performance, they have not been explicitly compared with each other. This work presents an analogous comparative study of four different methods. After a brief introduction, the four methods are compared in the aspects of time complexity and measurement needed by using an algorithm analysis. Then they are tested on the measurements generated from time domain simulations of the Northeast Power Coordinating Council (NPCC) 140-bus system. Following the case study, a detailed performance analysis is given, and the results can serve as a general guidance on choosing the TE identification methods and the corresponding parameters.
{"title":"A comparative study of measurement-based Thevenin equivalents identification methods","authors":"Haoyu Yuan, F. Li","doi":"10.1109/NAPS.2014.6965369","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965369","url":null,"abstract":"With the development of phasor measurement units (PMU), real-time voltage stability monitoring techniques using phasor measurements have been widely discussed in the past decade. For various measurement-based techniques, the fundamental idea behind them is to identify the Thevenin equivalents (TE) of the outer system seen from the nodes/areas of interests, and then assess the voltage stability margin based on the equivalent circuits. Therefore, fast and accurate identification of the TE is crucial for such online monitoring applications. Though several identification methods have been proposed claiming to achieve good performance, they have not been explicitly compared with each other. This work presents an analogous comparative study of four different methods. After a brief introduction, the four methods are compared in the aspects of time complexity and measurement needed by using an algorithm analysis. Then they are tested on the measurements generated from time domain simulations of the Northeast Power Coordinating Council (NPCC) 140-bus system. Following the case study, a detailed performance analysis is given, and the results can serve as a general guidance on choosing the TE identification methods and the corresponding parameters.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123696738","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965378
Lei Xiao, K. Holbert
The high voltage transmission and distribution lines are a source of electromagnetic fields, which may produce adverse effects on humans. Consequently, the magnitudes of the electric and magnetic fields are of increasing interest in a variety of situations, thus making it worthwhile to develop generalpurpose software that estimates both the electric and magnetic fields generated by power lines accurately. This paper deals with the simulations of the electric and magnetic fields under 500 kV lines. The simulations are carried out by Matlab for a horizontal conductor arrangement under balanced and unbalanced conditions, and for a vertical conductor arrangement. The results are compared with the IEEE standard for safety levels with respect to human exposure to electromagnetic fields.
{"title":"Development of software for calculating electromagnetic fields near power lines","authors":"Lei Xiao, K. Holbert","doi":"10.1109/NAPS.2014.6965378","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965378","url":null,"abstract":"The high voltage transmission and distribution lines are a source of electromagnetic fields, which may produce adverse effects on humans. Consequently, the magnitudes of the electric and magnetic fields are of increasing interest in a variety of situations, thus making it worthwhile to develop generalpurpose software that estimates both the electric and magnetic fields generated by power lines accurately. This paper deals with the simulations of the electric and magnetic fields under 500 kV lines. The simulations are carried out by Matlab for a horizontal conductor arrangement under balanced and unbalanced conditions, and for a vertical conductor arrangement. The results are compared with the IEEE standard for safety levels with respect to human exposure to electromagnetic fields.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121448767","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965427
P. Dehghanian, T. Popovic, M. Kezunovic
This paper presents a practical approach to evaluation of the operational health and reliability of circuit breakers in substations. Motivated by the recent failure surveys conducted by CIGRE working groups, circuit breaker condition data, obtained by monitoring critical parameters such as operational timings, tank gas pressure and temperature, mechanism traveling time and speed, etc., is used to evaluate the proposed health index. The proposed measure would help identify the transmission lines available for switching actions from the circuit breaker reliability view point. The proposed health index also provides a valuable input for substation maintenance personnel. The applicability of the proposed methodology is explored and validated using the actual circuit breaker condition data collected in the field.
{"title":"Circuit breaker operational health assessment via condition monitoring data","authors":"P. Dehghanian, T. Popovic, M. Kezunovic","doi":"10.1109/NAPS.2014.6965427","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965427","url":null,"abstract":"This paper presents a practical approach to evaluation of the operational health and reliability of circuit breakers in substations. Motivated by the recent failure surveys conducted by CIGRE working groups, circuit breaker condition data, obtained by monitoring critical parameters such as operational timings, tank gas pressure and temperature, mechanism traveling time and speed, etc., is used to evaluate the proposed health index. The proposed measure would help identify the transmission lines available for switching actions from the circuit breaker reliability view point. The proposed health index also provides a valuable input for substation maintenance personnel. The applicability of the proposed methodology is explored and validated using the actual circuit breaker condition data collected in the field.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122109120","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965406
Shruti Rao, D. Tylavsky, K. Alteneder, K. Brown, Jason Gunawardena, T. LaRose
Transformers are seldom loaded to their maximum capacity as per the existing industry practices. The ultimate goal of this research project is to develop a method for predicting the maximum dynamic loading capability without violating the thermal limits of the transformer's insulation. Dynamic loading must account for, at minimum, load magnitude and shape, the ambient temperature, the external cooling conditions and the thermal limits. This paper discusses methods of detecting irregularities in the cooling mode transitions for substation distribution transformers. The two HST and TOT models considered in this paper are the non-linear IEEE model and the model built using linear regression techniques.
{"title":"Methods to detect incorrect fan status for transformer thermal models","authors":"Shruti Rao, D. Tylavsky, K. Alteneder, K. Brown, Jason Gunawardena, T. LaRose","doi":"10.1109/NAPS.2014.6965406","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965406","url":null,"abstract":"Transformers are seldom loaded to their maximum capacity as per the existing industry practices. The ultimate goal of this research project is to develop a method for predicting the maximum dynamic loading capability without violating the thermal limits of the transformer's insulation. Dynamic loading must account for, at minimum, load magnitude and shape, the ambient temperature, the external cooling conditions and the thermal limits. This paper discusses methods of detecting irregularities in the cooling mode transitions for substation distribution transformers. The two HST and TOT models considered in this paper are the non-linear IEEE model and the model built using linear regression techniques.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"340 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117293256","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965459
S. Abdelrazek, S. Kamalasadan
In this paper we proposes a complete battery energy storage management scheme that include three functions of energy storage a) energy arbitrage b) PV smoothing c) voltage regulation. The proposed methodology enhances coordination of ancillary services applications like voltage support with Energy Time Shift (ETS) and Renewables Capacity Firming (RCF) applications and thus provides much higher value for battery energy storage devices. The design is tested on an EMTP simulation platform which indicates that the proposed architecture provides optimal control strategy for grid level storage for various functions proposed.
{"title":"A novel integrated optimal battery energy management control architecture considering multiple storage functions","authors":"S. Abdelrazek, S. Kamalasadan","doi":"10.1109/NAPS.2014.6965459","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965459","url":null,"abstract":"In this paper we proposes a complete battery energy storage management scheme that include three functions of energy storage a) energy arbitrage b) PV smoothing c) voltage regulation. The proposed methodology enhances coordination of ancillary services applications like voltage support with Energy Time Shift (ETS) and Renewables Capacity Firming (RCF) applications and thus provides much higher value for battery energy storage devices. The design is tested on an EMTP simulation platform which indicates that the proposed architecture provides optimal control strategy for grid level storage for various functions proposed.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122810190","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965402
D. Azari, S. S. Torbaghan, M. Gibescu, M. V. D. van der Meijden
This paper presents a planning framework to investigate the impact of different levels of integration of large-scale energy storage on the development plan of a meshed HVDC grid in a power system with large-scale offshore wind. In our problem formulation, the charge/discharge schedules of energy storage are modeled in such a way that market conditions in the succeeding hours are taken into account in the power dispatch at present. Both unlimited and limited energy storage capacity scenarios are considered, and compared to a no-storage reference case. The optimal plan includes grid topology, transmission capacities, energy storage capacities and optimal energy storage schedules. The optimization model sets the transmission capacities in such a way that transmission congestion revenue collected throughout the lifetime of the infrastructure pays off the investment cost of building the grid. The proposed model is applied to study the future development of an offshore grid in the North Sea. Simulation results are assessed according to various economic indicators. Investing in energy storage is shown to be economically effective for windy offshore regions.
{"title":"The impact of energy storage on long term transmission planning in the North Sea region","authors":"D. Azari, S. S. Torbaghan, M. Gibescu, M. V. D. van der Meijden","doi":"10.1109/NAPS.2014.6965402","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965402","url":null,"abstract":"This paper presents a planning framework to investigate the impact of different levels of integration of large-scale energy storage on the development plan of a meshed HVDC grid in a power system with large-scale offshore wind. In our problem formulation, the charge/discharge schedules of energy storage are modeled in such a way that market conditions in the succeeding hours are taken into account in the power dispatch at present. Both unlimited and limited energy storage capacity scenarios are considered, and compared to a no-storage reference case. The optimal plan includes grid topology, transmission capacities, energy storage capacities and optimal energy storage schedules. The optimization model sets the transmission capacities in such a way that transmission congestion revenue collected throughout the lifetime of the infrastructure pays off the investment cost of building the grid. The proposed model is applied to study the future development of an offshore grid in the North Sea. Simulation results are assessed according to various economic indicators. Investing in energy storage is shown to be economically effective for windy offshore regions.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127697816","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965404
Ali Hariri, M. Faruque
This paper studies the impacts on power quality due to the interconnection of multiple distributed generators on a distribution utility feeder. For this purpose, a Florida-based distribution feeder was modeled and studied by integrating different types of distributed generation (DG) sources. Different scenarios were implemented in which solar and wind plants were modeled with high variability of load and generation to observe their impacts on system's power quality. All the modeling and simulations were carried out using a high fidelity electromagnetic real-time transient simulation tool.
{"title":"Impacts of distributed generation on power quality","authors":"Ali Hariri, M. Faruque","doi":"10.1109/NAPS.2014.6965404","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965404","url":null,"abstract":"This paper studies the impacts on power quality due to the interconnection of multiple distributed generators on a distribution utility feeder. For this purpose, a Florida-based distribution feeder was modeled and studied by integrating different types of distributed generation (DG) sources. Different scenarios were implemented in which solar and wind plants were modeled with high variability of load and generation to observe their impacts on system's power quality. All the modeling and simulations were carried out using a high fidelity electromagnetic real-time transient simulation tool.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132937050","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965352
Kaci L. Kuntz, Michael Smith, K. Wedeward, Michael Collins
Power grids are monitored by gathering data through remote sensors and estimating the state of the grid. Bad data detection schemes detect and remove poor data. False data is a special type of data injection designed to evade typical bad data detection schemes and compromise state estimates, possibly leading to improper control of the grid. Topology perturbation is a situational awareness method that implements the use of distributed flexible AC transmission system devices to alter impedance on optimally chosen lines, updating the grid topology and exposing the presence of false data. The success of the topology perturbation for improving grid control and exposing false data in AC state estimation is demonstrated. A technique is developed for identifying the false data injection attack vector and quantifying the compromised measurements. The proposed method provides successful false data detection and identification in IEEE 14, 24, and 39-bus test systems using AC state estimation.
{"title":"Detecting, locating, & quantifying false data injections utilizing grid topology through optimized D-FACTS device placement","authors":"Kaci L. Kuntz, Michael Smith, K. Wedeward, Michael Collins","doi":"10.1109/NAPS.2014.6965352","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965352","url":null,"abstract":"Power grids are monitored by gathering data through remote sensors and estimating the state of the grid. Bad data detection schemes detect and remove poor data. False data is a special type of data injection designed to evade typical bad data detection schemes and compromise state estimates, possibly leading to improper control of the grid. Topology perturbation is a situational awareness method that implements the use of distributed flexible AC transmission system devices to alter impedance on optimally chosen lines, updating the grid topology and exposing the presence of false data. The success of the topology perturbation for improving grid control and exposing false data in AC state estimation is demonstrated. A technique is developed for identifying the false data injection attack vector and quantifying the compromised measurements. The proposed method provides successful false data detection and identification in IEEE 14, 24, and 39-bus test systems using AC state estimation.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"343 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124243321","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 : 2014-11-24DOI: 10.1109/NAPS.2014.6965430
V. Kekatos, G. Wang, G. Giannakis
Distribution systems will be critically challenged by reverse power flows and voltage fluctuations due to the integration of distributed renewable generation, demand response, and electric vehicles. Yet the same transformative changes coupled with advances in microelectronics offer new opportunities for reactive power management in distribution grids. In this context and considering the increasing time-variability of distributed generation and demand, a scheme for stochastic loss minimization is developed here. Given uncertain active power injections, a stochastic reactive control algorithm is devised. Leveraging the recent convex relaxation of optimal power flow problems, it is shown that the subgradient of the power losses can be obtained as the Lagrange multiplier of the related second-order cone program (SOCP). Numerical tests on a 47-bus test feeder with high photovoltaic penetration corroborates the power efficiency and voltage profile advantage of the novel stochastic method over its deterministic alternative.
{"title":"Stochastic loss minimization for power distribution networks","authors":"V. Kekatos, G. Wang, G. Giannakis","doi":"10.1109/NAPS.2014.6965430","DOIUrl":"https://doi.org/10.1109/NAPS.2014.6965430","url":null,"abstract":"Distribution systems will be critically challenged by reverse power flows and voltage fluctuations due to the integration of distributed renewable generation, demand response, and electric vehicles. Yet the same transformative changes coupled with advances in microelectronics offer new opportunities for reactive power management in distribution grids. In this context and considering the increasing time-variability of distributed generation and demand, a scheme for stochastic loss minimization is developed here. Given uncertain active power injections, a stochastic reactive control algorithm is devised. Leveraging the recent convex relaxation of optimal power flow problems, it is shown that the subgradient of the power losses can be obtained as the Lagrange multiplier of the related second-order cone program (SOCP). Numerical tests on a 47-bus test feeder with high photovoltaic penetration corroborates the power efficiency and voltage profile advantage of the novel stochastic method over its deterministic alternative.","PeriodicalId":421766,"journal":{"name":"2014 North American Power Symposium (NAPS)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123640621","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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