Pub Date : 2007-10-01DOI: 10.1109/EPC.2007.4520379
Y. Lang, Bin Wu, N. Zargari
In this paper, a PWM current source converter is proposed for high-power wind energy system using a Permanent Magnetic Synchronous Generator (PMSG). The current source converter normally requires filter capacitors on its ac side, which may affect power factor of the system. A decoupled active/reactive power control algorithm is proposed for the grid-side power factor adjustment. The dc current reference is generated in a way to meet the requirements from both sides. In addition, Field Oriented Control theory is used for the wind generator control. Experiments on a small-scale laboratory have been carried out to verify the analysis and experimental results are presented.
{"title":"Reactive Power Control of Current Source Converter based Wind Energy System","authors":"Y. Lang, Bin Wu, N. Zargari","doi":"10.1109/EPC.2007.4520379","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520379","url":null,"abstract":"In this paper, a PWM current source converter is proposed for high-power wind energy system using a Permanent Magnetic Synchronous Generator (PMSG). The current source converter normally requires filter capacitors on its ac side, which may affect power factor of the system. A decoupled active/reactive power control algorithm is proposed for the grid-side power factor adjustment. The dc current reference is generated in a way to meet the requirements from both sides. In addition, Field Oriented Control theory is used for the wind generator control. Experiments on a small-scale laboratory have been carried out to verify the analysis and experimental results are presented.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132200669","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520386
Y. Biletskiy, Ning Chang, A. Sharaf, H. Mahasneh
The paper presents an identification scheme for on-line monitoring and identification of power quality and system disturbances caused by nonlinear loads. The wide proliferation of distributed renewable energy and green power sources, and rapid changes in utility load types with drive towards deregulation of the power market require affordable and robust on-line data acquisition and expert identification systems, especially for the utilization grid power systems. The proposed technique allows creating such expert systems with the extensible knowledge base, which can be used for identification of power distortion events created by consumer nonlinear loads.
{"title":"A Monitoring and Identification Scheme for Power Quality Assessment","authors":"Y. Biletskiy, Ning Chang, A. Sharaf, H. Mahasneh","doi":"10.1109/EPC.2007.4520386","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520386","url":null,"abstract":"The paper presents an identification scheme for on-line monitoring and identification of power quality and system disturbances caused by nonlinear loads. The wide proliferation of distributed renewable energy and green power sources, and rapid changes in utility load types with drive towards deregulation of the power market require affordable and robust on-line data acquisition and expert identification systems, especially for the utilization grid power systems. The proposed technique allows creating such expert systems with the extensible knowledge base, which can be used for identification of power distortion events created by consumer nonlinear loads.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134153790","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520372
A. Algarni, Kankar Bhattacharya
A comprehensive operational planning model for a disco operating in a competitive environment is presented in this paper. The operational planning function is a two-level model in which the first level deals with the disco's activities in the day- ahead stage. In the second level, the model deals with the disco's activities in the real-time stage. The first level model determines the disco's operational decisions with regard to its grid purchase, scheduling of any distributed generation (DG) sources owned by it, or purchase scheduling of investor-owned DG, contracting for interruptible loads. These decisions are imposed as binding constraints in the real-time model and the disco seeks to minimize its short-term costs keeping in mind its day-ahead decisions. A case-study is carried out considering the well-known 33-bus distribution system.
{"title":"A Comprehensive Short-Term Operations Framework for a Disco in Competitive Electricity Markets","authors":"A. Algarni, Kankar Bhattacharya","doi":"10.1109/EPC.2007.4520372","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520372","url":null,"abstract":"A comprehensive operational planning model for a disco operating in a competitive environment is presented in this paper. The operational planning function is a two-level model in which the first level deals with the disco's activities in the day- ahead stage. In the second level, the model deals with the disco's activities in the real-time stage. The first level model determines the disco's operational decisions with regard to its grid purchase, scheduling of any distributed generation (DG) sources owned by it, or purchase scheduling of investor-owned DG, contracting for interruptible loads. These decisions are imposed as binding constraints in the real-time model and the disco seeks to minimize its short-term costs keeping in mind its day-ahead decisions. A case-study is carried out considering the well-known 33-bus distribution system.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130506974","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520375
S. Nuchprayoon, N. Wiraphorn
This paper presents an implementation of capacitor placement and voltage reduction on distribution feeder. The objectives of this implementation are to obtain a flat voltage profile and reduce real power losses on distribution feeder. As a result, feeder capacity can be released and excess generation capacity could be avoided during peak-load periods. By installing capacitor banks on distribution feeder, cost allocation scheme between electric utility and small power producers is described. The proposed strategy has been tested with a 5-bus and 11-bus feeder models. The benefits of the proposed strategy depend on the load characteristics. The higher portion of voltage-dependent loads, the more benefits gained from voltage reduction.
{"title":"Implementation of Capacitor Placement and Voltage Reduction on Distribution Feeder","authors":"S. Nuchprayoon, N. Wiraphorn","doi":"10.1109/EPC.2007.4520375","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520375","url":null,"abstract":"This paper presents an implementation of capacitor placement and voltage reduction on distribution feeder. The objectives of this implementation are to obtain a flat voltage profile and reduce real power losses on distribution feeder. As a result, feeder capacity can be released and excess generation capacity could be avoided during peak-load periods. By installing capacitor banks on distribution feeder, cost allocation scheme between electric utility and small power producers is described. The proposed strategy has been tested with a 5-bus and 11-bus feeder models. The benefits of the proposed strategy depend on the load characteristics. The higher portion of voltage-dependent loads, the more benefits gained from voltage reduction.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131546445","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520313
G. Kumar, B. Karney
The electricity usage with respect to water distribution systems is examined for the particular case of Ontario. The case is made that the integration of conservation and energy efficiency measures between the utilities would leverage investments better than isolated efforts. The similarities between water and energy production are highlighted and potential energy savings for water distribution systems are presented. Preliminary calculations of these savings yielded a 11- 27 MW power reduction over the daily cycle for leakage protection. These values were derived from the gross, yet conservative total of 57 MW, if all the leakage in hydraulic conduits was contained. Electrical load shifting (peak shaving) through active pumping for water distribution systems yielded a potential between 450 and 100 MW of freed up generation. It should be noted that the higher value of 450 is still conservative and that this could be significantly higher for the province if distributed storage was actively implemented.
{"title":"Electricity Usage in Water Distribution Networks","authors":"G. Kumar, B. Karney","doi":"10.1109/EPC.2007.4520313","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520313","url":null,"abstract":"The electricity usage with respect to water distribution systems is examined for the particular case of Ontario. The case is made that the integration of conservation and energy efficiency measures between the utilities would leverage investments better than isolated efforts. The similarities between water and energy production are highlighted and potential energy savings for water distribution systems are presented. Preliminary calculations of these savings yielded a 11- 27 MW power reduction over the daily cycle for leakage protection. These values were derived from the gross, yet conservative total of 57 MW, if all the leakage in hydraulic conduits was contained. Electrical load shifting (peak shaving) through active pumping for water distribution systems yielded a potential between 450 and 100 MW of freed up generation. It should be noted that the higher value of 450 is still conservative and that this could be significantly higher for the province if distributed storage was actively implemented.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"191 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131674288","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520380
S. Auddy, R. Varma, M. Dang
With the increased penetration of wind power it is important to carefully asses the impact of grid integration of wind turbine generators. Accurate wind turbine generator models are required for this purpose. Variable speed wind turbine generators are widely being interconnected to the grid to ensure optimum power capture from the wind energy. In this paper, an attempt is made to validate a variable speed doubly fed induction generator model with the field test results. The GE 1.5 MW wind turbine generator is a good example of doubly fed induction generator configuration which is already implemented in PSS/E software. These wind turbine generators are actually installed in the AIM Erie Shore Wind Generating Station of Hydro One Network Inc. A series of tests were performed in this wind farm in 2006 winter. A few of the tests are simulated in PSS/E to validate the existing models. Simulation results are found to be in good agreement with the field test results confirming the accuracy of the GE 1.5 MW wind turbine generator (WTG) models of PSS/E wind. The reasons for the mismatch between the simulation and actual results are also pointed out.
{"title":"Field Validation of a Doubly Fed Induction Generator (DFIG) Model","authors":"S. Auddy, R. Varma, M. Dang","doi":"10.1109/EPC.2007.4520380","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520380","url":null,"abstract":"With the increased penetration of wind power it is important to carefully asses the impact of grid integration of wind turbine generators. Accurate wind turbine generator models are required for this purpose. Variable speed wind turbine generators are widely being interconnected to the grid to ensure optimum power capture from the wind energy. In this paper, an attempt is made to validate a variable speed doubly fed induction generator model with the field test results. The GE 1.5 MW wind turbine generator is a good example of doubly fed induction generator configuration which is already implemented in PSS/E software. These wind turbine generators are actually installed in the AIM Erie Shore Wind Generating Station of Hydro One Network Inc. A series of tests were performed in this wind farm in 2006 winter. A few of the tests are simulated in PSS/E to validate the existing models. Simulation results are found to be in good agreement with the field test results confirming the accuracy of the GE 1.5 MW wind turbine generator (WTG) models of PSS/E wind. The reasons for the mismatch between the simulation and actual results are also pointed out.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124858430","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520324
G. Madescu, A. Trică, N. Budisan, O. Proștean, M. Biriescu, M. Mot
The paper discusses the optimization of low speed induction generators, directly coupled to the shaft of the turbines in variable-speed wind power generation systems. These low speed induction generators have a big number of poles and, as a consequence, low performance and big stator outer diameter. Because of the variable speed, a power electronic converter has to be used to deliver the produced energy to the grid. By using such a converter, the number of poles can be reduced and the rated generator frequency also decreased to an arbitrary nominal frequency. Both number of poles and rated frequency will be determined within reasonable limits as part of an optimization problem. The objective-function of this optimization is to maximize the product between efficiency and power factor without any geometrical or economical restrictions. Maximum values of this product provide high generator efficiency and lowest generator current and, in consequence, the lowest cost of the converter. The aim of the paper is to emphasize that the low speed induction generators with power electronic converters represent a realistic and useful solution for direct drive wind power application.
{"title":"Performance optimization of low-speed induction generators for direct drive wind turbines","authors":"G. Madescu, A. Trică, N. Budisan, O. Proștean, M. Biriescu, M. Mot","doi":"10.1109/EPC.2007.4520324","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520324","url":null,"abstract":"The paper discusses the optimization of low speed induction generators, directly coupled to the shaft of the turbines in variable-speed wind power generation systems. These low speed induction generators have a big number of poles and, as a consequence, low performance and big stator outer diameter. Because of the variable speed, a power electronic converter has to be used to deliver the produced energy to the grid. By using such a converter, the number of poles can be reduced and the rated generator frequency also decreased to an arbitrary nominal frequency. Both number of poles and rated frequency will be determined within reasonable limits as part of an optimization problem. The objective-function of this optimization is to maximize the product between efficiency and power factor without any geometrical or economical restrictions. Maximum values of this product provide high generator efficiency and lowest generator current and, in consequence, the lowest cost of the converter. The aim of the paper is to emphasize that the low speed induction generators with power electronic converters represent a realistic and useful solution for direct drive wind power application.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122837946","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520336
H. Jabr, N. Kar
Wound-rotor induction generator has numerous advantages in wind power generation over other types of generators. One scheme is realized when a converter cascade is used between the slip-ring terminals and the utility grid to control the rotor power. This configuration is called the doubly-fed induction generator (DFIG). A vector control scheme is developed to control the rotor side voltage source converter. This scheme allows the independent control of the generated active and reactive power as well as the rotor speed to track the maximum wind power point. In this work, a neuro-fuzzy gain tuner is proposed to control the DFIG. Vector control is used to allow independent control of the generator speed, active and reactive power. Six neuro-fuzzy gain tuners are used, two for each controlled variable. The input for each neuro-fuzzy system is the error value of speed, active or reactive power. The choice of only one input to the system simplifies the design and reduces the computational burden while giving excellent overall system performance.
{"title":"Neuro-Fuzzy Vector Control for Doubly-Fed Wind Driven Induction Generator","authors":"H. Jabr, N. Kar","doi":"10.1109/EPC.2007.4520336","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520336","url":null,"abstract":"Wound-rotor induction generator has numerous advantages in wind power generation over other types of generators. One scheme is realized when a converter cascade is used between the slip-ring terminals and the utility grid to control the rotor power. This configuration is called the doubly-fed induction generator (DFIG). A vector control scheme is developed to control the rotor side voltage source converter. This scheme allows the independent control of the generated active and reactive power as well as the rotor speed to track the maximum wind power point. In this work, a neuro-fuzzy gain tuner is proposed to control the DFIG. Vector control is used to allow independent control of the generator speed, active and reactive power. Six neuro-fuzzy gain tuners are used, two for each controlled variable. The input for each neuro-fuzzy system is the error value of speed, active or reactive power. The choice of only one input to the system simplifies the design and reduces the computational burden while giving excellent overall system performance.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125574752","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520377
M. Rosen
The benefits of using exergy to understand the efficiencies of electrical technologies and systems and to guide improvement efforts are demonstrated. Although exergy applications in electrical engineering are uncommon, exergy clearly identifies efficiency improvements and reductions in thermodynamic losses for electrical technologies and systems. A range of devices is considered, including simple electrical conversion devices, power generation systems, generation systems for multiple products including electricity, and devices that use or are driven by electricity. The information provided by energy assessments is shown to be less useful than that provided by exergy and prone to be misleading. It is concluded that exergy has a significant role to play in evaluating and increasing the efficiencies of electrical technologies and systems, and should prove useful to engineers as well as decision and policy makers.
{"title":"Improving the Efficiency of Electrical Systems via Exergy Methods","authors":"M. Rosen","doi":"10.1109/EPC.2007.4520377","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520377","url":null,"abstract":"The benefits of using exergy to understand the efficiencies of electrical technologies and systems and to guide improvement efforts are demonstrated. Although exergy applications in electrical engineering are uncommon, exergy clearly identifies efficiency improvements and reductions in thermodynamic losses for electrical technologies and systems. A range of devices is considered, including simple electrical conversion devices, power generation systems, generation systems for multiple products including electricity, and devices that use or are driven by electricity. The information provided by energy assessments is shown to be less useful than that provided by exergy and prone to be misleading. It is concluded that exergy has a significant role to play in evaluating and increasing the efficiencies of electrical technologies and systems, and should prove useful to engineers as well as decision and policy makers.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115369997","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520354
P. Campbell
As the world strives to identify and develop sustainable alternatives to fossil fuels a fundamental obstacle to successful integration has been the inability to accurately estimate the potential yield from sustainable energy sources. The most difficult of all sustainable resources is Wind, due to its dynamic nature. Many approaches exist to generate forecasts for wind regime. In general, these models can be classified as either involving a numerical weather prediction model (NWP) or not. The past fifteen years have been a very intensive period for forecasting research and development. However, it is also clearly demonstrated that this work is being carried out from the perspective of the large utility. Whilst this is acceptable in the Danish, Swedish and American markets, were the majority of wind parks are owned and operated by such organizations, it does not hold true for developing markets where the majority of wind parks are under the operational control of smaller organizations, which do not have sufficient expertise or budgetary ability to pursue such ambitious projects. This study presents a number of methodologies for forecast generation and compares the approaches to the industry standard across a variety of forecast horizons.
{"title":"Short-Term Wind Energy Forecasting","authors":"P. Campbell","doi":"10.1109/EPC.2007.4520354","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520354","url":null,"abstract":"As the world strives to identify and develop sustainable alternatives to fossil fuels a fundamental obstacle to successful integration has been the inability to accurately estimate the potential yield from sustainable energy sources. The most difficult of all sustainable resources is Wind, due to its dynamic nature. Many approaches exist to generate forecasts for wind regime. In general, these models can be classified as either involving a numerical weather prediction model (NWP) or not. The past fifteen years have been a very intensive period for forecasting research and development. However, it is also clearly demonstrated that this work is being carried out from the perspective of the large utility. Whilst this is acceptable in the Danish, Swedish and American markets, were the majority of wind parks are owned and operated by such organizations, it does not hold true for developing markets where the majority of wind parks are under the operational control of smaller organizations, which do not have sufficient expertise or budgetary ability to pursue such ambitious projects. This study presents a number of methodologies for forecast generation and compares the approaches to the industry standard across a variety of forecast horizons.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127354950","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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