Pub Date : 2010-07-25DOI: 10.1109/PES.2010.5589407
Anupama Kowli, M. Negrete-Pincetic, G. Gross
The effective harnessing of control, communication and computer technologies in the operation of the power system - the key notion behind the Smart Grid concept - can markedly impact the system reliability. The appropriate utilization of intelligent line switching, demand response resources (DRRs), FACTS devices and PMUs is key in the smart grid deployment to bring about improvements in the reliability of the power system. While the Smart Grid can support the provision of differentiated levels of reliability to different customers, the maintenance of system integrity requires that a certain minimum level of reliability be kept throughout the system. We view the provision to meet this reliability requirement as a public good. In this paper, we consider the long-term impacts of DRRs - a successful application of the smart grid - and evaluate their impacts on system reliability. We use a simulation engine to study these impacts under different scenarios. We demonstrate the tangible reliability benefits of DRR applications in terms of reduced number of loss of load events as a result of voluntary load curtailments.
{"title":"A successful implementation with the Smart Grid: Demand response resources","authors":"Anupama Kowli, M. Negrete-Pincetic, G. Gross","doi":"10.1109/PES.2010.5589407","DOIUrl":"https://doi.org/10.1109/PES.2010.5589407","url":null,"abstract":"The effective harnessing of control, communication and computer technologies in the operation of the power system - the key notion behind the Smart Grid concept - can markedly impact the system reliability. The appropriate utilization of intelligent line switching, demand response resources (DRRs), FACTS devices and PMUs is key in the smart grid deployment to bring about improvements in the reliability of the power system. While the Smart Grid can support the provision of differentiated levels of reliability to different customers, the maintenance of system integrity requires that a certain minimum level of reliability be kept throughout the system. We view the provision to meet this reliability requirement as a public good. In this paper, we consider the long-term impacts of DRRs - a successful application of the smart grid - and evaluate their impacts on system reliability. We use a simulation engine to study these impacts under different scenarios. We demonstrate the tangible reliability benefits of DRR applications in terms of reduced number of loss of load events as a result of voluntary load curtailments.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129392218","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 : 2010-07-25DOI: 10.1109/PES.2010.5589405
A. Papavasiliou, S. Oren
In this paper we propose a direct coupling of renewable generation with deferrable demand in order to mitigate the unpredictable and non-controllable fluctuation of renewable power supply. We cast our problem in the form of a stochastic dynamic program and we characterize the value function of the problem in order to develop efficient solution methods. We develop and compare two algorithms for optimally supplying renewable power to time-flexible electricity loads in the presence of a spot market, backward dynamic programming and approximate dynamic programming. We describe how our proposition compares to price responsive demand in terms capacity gains and energy market revenues for renewable generators, and we determine the optimal capacity of deferrable demand which can be reliably coupled to renewable generation.
{"title":"Supplying renewable energy to deferrable loads: Algorithms and economic analysis","authors":"A. Papavasiliou, S. Oren","doi":"10.1109/PES.2010.5589405","DOIUrl":"https://doi.org/10.1109/PES.2010.5589405","url":null,"abstract":"In this paper we propose a direct coupling of renewable generation with deferrable demand in order to mitigate the unpredictable and non-controllable fluctuation of renewable power supply. We cast our problem in the form of a stochastic dynamic program and we characterize the value function of the problem in order to develop efficient solution methods. We develop and compare two algorithms for optimally supplying renewable power to time-flexible electricity loads in the presence of a spot market, backward dynamic programming and approximate dynamic programming. We describe how our proposition compares to price responsive demand in terms capacity gains and energy market revenues for renewable generators, and we determine the optimal capacity of deferrable demand which can be reliably coupled to renewable generation.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131001312","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 : 2010-07-25DOI: 10.1109/PES.2010.5589388
Jun Wei Chuah, A. Raghunathan, N. Jha
Energy-saving technologies have become more readily available for residential purposes. Such technologies can be classified into two broad categories: energy generation systems and consumption reduction solutions. In the first half of this paper, we analyze the feasibility of renewable energy generation systems at home. Our results indicate that although renewable energy can possibly fulfill a significant portion of a household's electricity demand, the costs involved will be a strong barrier to their adoption. Typically, it would take upwards of 10 years to realize a return on the initial investment in installing such systems. This strengthens the argument for government subsidies until manufacturing processes become mature enough to enable cheaper solutions. A more direct method of reducing home electricity costs would be to reduce consumption. In the second half of this paper, we analyze a simple means towards consumption reduction - switching to energy-efficient light bulbs. Our calculations indicate that compact fluorescent lamps (CFLs) are four times less expensive to run than incandescent light bulbs. This takes into account both the unit cost and the runtime cost of the light bulbs. The use of CFLs, coupled with a smart lighting system that automatically shuts off when not in use, may allow up to 83% reduction of household electricity consumption on lighting (or around 7% reduction of total electricity consumption at home).
{"title":"An evaluation of energy-saving technologies for residential purposes","authors":"Jun Wei Chuah, A. Raghunathan, N. Jha","doi":"10.1109/PES.2010.5589388","DOIUrl":"https://doi.org/10.1109/PES.2010.5589388","url":null,"abstract":"Energy-saving technologies have become more readily available for residential purposes. Such technologies can be classified into two broad categories: energy generation systems and consumption reduction solutions. In the first half of this paper, we analyze the feasibility of renewable energy generation systems at home. Our results indicate that although renewable energy can possibly fulfill a significant portion of a household's electricity demand, the costs involved will be a strong barrier to their adoption. Typically, it would take upwards of 10 years to realize a return on the initial investment in installing such systems. This strengthens the argument for government subsidies until manufacturing processes become mature enough to enable cheaper solutions. A more direct method of reducing home electricity costs would be to reduce consumption. In the second half of this paper, we analyze a simple means towards consumption reduction - switching to energy-efficient light bulbs. Our calculations indicate that compact fluorescent lamps (CFLs) are four times less expensive to run than incandescent light bulbs. This takes into account both the unit cost and the runtime cost of the light bulbs. The use of CFLs, coupled with a smart lighting system that automatically shuts off when not in use, may allow up to 83% reduction of household electricity consumption on lighting (or around 7% reduction of total electricity consumption at home).","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132876995","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 : 2010-07-25DOI: 10.1109/PES.2010.5589941
Y. Pipelzadeh, B. Chaudhuri, T. Green
A case study on the Australian equivalent system - recently adopted as an IEEE benchmark for stability studies - is presented here to illustrate power oscillation damping through HVDC links. Wide-area signals are used for supplementary modulation of the HVDC power order driven through a multivariable controller. The test case is set up in DIgSILENT and benchmarked against the standard results. Linearized model around the nominal condition is obtained by using subspace identification on a set of measurements derived out of probing the system through the HVDC link. Modal analysis is carried out to identify a set of appropriate feedback signals for the controller. Pole-placement technique is used to design a multi-input, single-output (MISO) controller in two different frameworks - i) observer driven state feedback and ii) optimized lead-lag compensators. The effectiveness of HVDC modulation for power oscillation damping is validated through eigen-value analysis and non-linear simulation (in DIgSILENT) over a range of operating conditions.
{"title":"Wide-area power oscillation damping control through HVDC: A case study on Australian equivalent system","authors":"Y. Pipelzadeh, B. Chaudhuri, T. Green","doi":"10.1109/PES.2010.5589941","DOIUrl":"https://doi.org/10.1109/PES.2010.5589941","url":null,"abstract":"A case study on the Australian equivalent system - recently adopted as an IEEE benchmark for stability studies - is presented here to illustrate power oscillation damping through HVDC links. Wide-area signals are used for supplementary modulation of the HVDC power order driven through a multivariable controller. The test case is set up in DIgSILENT and benchmarked against the standard results. Linearized model around the nominal condition is obtained by using subspace identification on a set of measurements derived out of probing the system through the HVDC link. Modal analysis is carried out to identify a set of appropriate feedback signals for the controller. Pole-placement technique is used to design a multi-input, single-output (MISO) controller in two different frameworks - i) observer driven state feedback and ii) optimized lead-lag compensators. The effectiveness of HVDC modulation for power oscillation damping is validated through eigen-value analysis and non-linear simulation (in DIgSILENT) over a range of operating conditions.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133592076","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 : 2010-07-25DOI: 10.1109/PES.2010.5589713
Congcong Wang, P. Luh, P. Gribik, Li Zhang, Tengshun Peng
In current deregulated power markets, prices are determined in the economic dispatch problem with fixed unit commitment decisions. Start-up and no-load costs are not included in the prices and significant uplift payments have to be paid to generators. The convex hull pricing model was developed to include the fixed costs in setting prices by solving the dual of the unit commitment and economic dispatch problem. The optimal multipliers are the convex hull prices, and the prices minimize the uplift payments. The optimal multipliers can be obtained by using cutting plane methods that iteratively shrink the feasible polyhedron in the dual space to the optimal point. The calculation of query points is a key step for cutting plane methods and centers such as center of gravity and analytic center are reported as the query point. To calculate the convex hull prices in a more efficient way, this paper develops a subgradient-simplex based cutting plane method to find a query point along the subgradient. When the query point is not deep inside, a sphere inscribed in a corner or the Chebyshev center is calculated by the use of simplex tableaus to ensure the query point is always deep inside. Redundant constraints are also pruned based on the tableaus.
{"title":"The subgradient-simplex based cutting plane method for convex hull pricing","authors":"Congcong Wang, P. Luh, P. Gribik, Li Zhang, Tengshun Peng","doi":"10.1109/PES.2010.5589713","DOIUrl":"https://doi.org/10.1109/PES.2010.5589713","url":null,"abstract":"In current deregulated power markets, prices are determined in the economic dispatch problem with fixed unit commitment decisions. Start-up and no-load costs are not included in the prices and significant uplift payments have to be paid to generators. The convex hull pricing model was developed to include the fixed costs in setting prices by solving the dual of the unit commitment and economic dispatch problem. The optimal multipliers are the convex hull prices, and the prices minimize the uplift payments. The optimal multipliers can be obtained by using cutting plane methods that iteratively shrink the feasible polyhedron in the dual space to the optimal point. The calculation of query points is a key step for cutting plane methods and centers such as center of gravity and analytic center are reported as the query point. To calculate the convex hull prices in a more efficient way, this paper develops a subgradient-simplex based cutting plane method to find a query point along the subgradient. When the query point is not deep inside, a sphere inscribed in a corner or the Chebyshev center is calculated by the use of simplex tableaus to ensure the query point is always deep inside. Redundant constraints are also pruned based on the tableaus.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"15 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133705453","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 : 2010-07-25DOI: 10.1109/PES.2010.5589562
C. Feltes, S. Engelhardt, J. Kretschmann, J. Fortmann, I. Erlich
Current grid codes require the fault ride-through capability of modern wind turbines. During grid faults the reactive current control of the wind turbines should be used to support the grid voltage. With modern protection devices the fault durations are normally in a range of some hundred milliseconds or less. However this time window may be decisive for the stability of the conventional generators connected to the grid and consequently for the whole system. In this regard the dynamic response of the voltage support by the generation units is a very important issue. New German grid codes address this subject by specifying timing rules for the system response to grid faults. While wind turbines equipped with full-size converters can fulfil these rules with moderate effort due to their fast converter control, DFIG-based wind turbines are facing a new big challenge, which requires a dedicated control. This paper shows an extended control approach that deals with a highly dynamic response to grid faults. Simulation results prove the good performance of this control and validate it based on the new requirements.
{"title":"Dynamic performance evaluation of DFIG-based wind turbines regarding new German grid code requirements","authors":"C. Feltes, S. Engelhardt, J. Kretschmann, J. Fortmann, I. Erlich","doi":"10.1109/PES.2010.5589562","DOIUrl":"https://doi.org/10.1109/PES.2010.5589562","url":null,"abstract":"Current grid codes require the fault ride-through capability of modern wind turbines. During grid faults the reactive current control of the wind turbines should be used to support the grid voltage. With modern protection devices the fault durations are normally in a range of some hundred milliseconds or less. However this time window may be decisive for the stability of the conventional generators connected to the grid and consequently for the whole system. In this regard the dynamic response of the voltage support by the generation units is a very important issue. New German grid codes address this subject by specifying timing rules for the system response to grid faults. While wind turbines equipped with full-size converters can fulfil these rules with moderate effort due to their fast converter control, DFIG-based wind turbines are facing a new big challenge, which requires a dedicated control. This paper shows an extended control approach that deals with a highly dynamic response to grid faults. Simulation results prove the good performance of this control and validate it based on the new requirements.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133429659","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 : 2010-07-25DOI: 10.1109/PES.2010.5589545
M. Falvo, F. Foiadelli
The paper presents a new proposal for the design of a sustainable urban mobility system. Starting from an overview on the worldwide existing solutions and on the future trend, an innovative idea regarding the integration of two urban mobility systems is proposed: a metro transit system in underground and an electric and hybrid vehicles transport system on surface. The integration is aimed at the reduction of energy consumptions and environmental impact and at the optimization of the service thanks to the maximization of the transport bid in time. Moreover the proposed solution guarantees the minimum economic impact as a result of the optimization of the logistic and technological application of the existing electric power plant. The main results about the preliminary energy analysis, that is the basis of the project, are reported.
{"title":"Preliminary analysis for the design of an energy-efficient and environmental sustainable integrated mobility system","authors":"M. Falvo, F. Foiadelli","doi":"10.1109/PES.2010.5589545","DOIUrl":"https://doi.org/10.1109/PES.2010.5589545","url":null,"abstract":"The paper presents a new proposal for the design of a sustainable urban mobility system. Starting from an overview on the worldwide existing solutions and on the future trend, an innovative idea regarding the integration of two urban mobility systems is proposed: a metro transit system in underground and an electric and hybrid vehicles transport system on surface. The integration is aimed at the reduction of energy consumptions and environmental impact and at the optimization of the service thanks to the maximization of the transport bid in time. Moreover the proposed solution guarantees the minimum economic impact as a result of the optimization of the logistic and technological application of the existing electric power plant. The main results about the preliminary energy analysis, that is the basis of the project, are reported.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133679130","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 : 2010-07-25DOI: 10.1109/PES.2010.5589641
N. Kang, Y. Liao
This paper presents a general approach to locate any type of fault on either a single-circuit or a double-circuit transmission line when only voltage sag data are available. The voltage measurements employed can be from one bus, two buses, or more buses, which are not restricted to those of the faulted section. It is assumed that the network data are available and the fault type is known. Quite encouraging results have been obtained based on EMTP simulation studies.
{"title":"Fault location estimation for transmission lines using voltage sag data","authors":"N. Kang, Y. Liao","doi":"10.1109/PES.2010.5589641","DOIUrl":"https://doi.org/10.1109/PES.2010.5589641","url":null,"abstract":"This paper presents a general approach to locate any type of fault on either a single-circuit or a double-circuit transmission line when only voltage sag data are available. The voltage measurements employed can be from one bus, two buses, or more buses, which are not restricted to those of the faulted section. It is assumed that the network data are available and the fault type is known. Quite encouraging results have been obtained based on EMTP simulation studies.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132182014","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 : 2010-07-25DOI: 10.1109/PES.2010.5588170
Y. Hida, R. Yokoyama, J. Shimizukawa, K. Iba, K. Tanaka, T. Seki
Among various types of battery energy storage systems (BESSs), NAS battery is the most promising products. NAS battery is a commercial product implemented widely in the world. The first purpose of BESS was improvement of load factors. The second purpose is improvement of power quality, especially against voltage-sag. The recent interest is oriented to utilize BESS to mitigate the intermittency of renewable energy.
{"title":"Load following operation of NAS battery by setting statistic margins to avoid risks","authors":"Y. Hida, R. Yokoyama, J. Shimizukawa, K. Iba, K. Tanaka, T. Seki","doi":"10.1109/PES.2010.5588170","DOIUrl":"https://doi.org/10.1109/PES.2010.5588170","url":null,"abstract":"Among various types of battery energy storage systems (BESSs), NAS battery is the most promising products. NAS battery is a commercial product implemented widely in the world. The first purpose of BESS was improvement of load factors. The second purpose is improvement of power quality, especially against voltage-sag. The recent interest is oriented to utilize BESS to mitigate the intermittency of renewable energy.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132235496","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 : 2010-07-25DOI: 10.1109/PES.2010.5589345
K. Chen, L. Montgomery, G. Klempner, J. Yagielski, J. Amos, M. Brimsek, M. Sedlak
This report is an annual progress report by the Generator Subcommittee of the Electrical Machinery Committee of the IEEE Power and Energy Society, Working Group No. 8 (“IEEE C50.13 Review & Compare”). This working group is tasked to compare the 2005 revision of the IEEE C50.13 standard for large round rotor synchronous generators with recent revisions of comparable International Electrotechnical Commission (IEC) 60034 standards. The intention of this paper is to report the progress this working group had made, highlight some significant comparison findings, outline the next step planning of this project and call for more industry support.
{"title":"Comparing IEEE 50.13 and IEC 60034 standards for large cylindrical rotor synchronous machines","authors":"K. Chen, L. Montgomery, G. Klempner, J. Yagielski, J. Amos, M. Brimsek, M. Sedlak","doi":"10.1109/PES.2010.5589345","DOIUrl":"https://doi.org/10.1109/PES.2010.5589345","url":null,"abstract":"This report is an annual progress report by the Generator Subcommittee of the Electrical Machinery Committee of the IEEE Power and Energy Society, Working Group No. 8 (“IEEE C50.13 Review & Compare”). This working group is tasked to compare the 2005 revision of the IEEE C50.13 standard for large round rotor synchronous generators with recent revisions of comparable International Electrotechnical Commission (IEC) 60034 standards. The intention of this paper is to report the progress this working group had made, highlight some significant comparison findings, outline the next step planning of this project and call for more industry support.","PeriodicalId":177545,"journal":{"name":"IEEE PES General Meeting","volume":"402 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133084749","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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