Pub Date : 2012-12-01DOI: 10.1109/POWERCON.2012.6401449
A. Supriyadi, H. Takano, J. Murata, T. Goda, T. Hashiguchi
This paper presents an adaptive pitch and a battery controller design based on a system estimator. The approach presented in this research uses an online identification system, which updated whenever the estimated model mismatch exceeds predetermined bounds. Based on the redesigned model, an adaptive PID and lead-lag controller will be re-tuned using genetic algorithm (GA). The optimization problems are formulated to increase the damping ratio and place the dominant mode in a D-shape region. The GA is applied to solve the optimization problem and to achieve control parameters. The performance of the proposed adaptive controller has been investigated in a hybrid wind-diesel power system in comparison with conventional controller. Simulation results confirm that damping effect of the proposed adaptive controllers are much better that of the conventional controllers against various operating.
{"title":"Adaptive Frequency Control for Hybrid Wind-Diesel power system using system estimator","authors":"A. Supriyadi, H. Takano, J. Murata, T. Goda, T. Hashiguchi","doi":"10.1109/POWERCON.2012.6401449","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401449","url":null,"abstract":"This paper presents an adaptive pitch and a battery controller design based on a system estimator. The approach presented in this research uses an online identification system, which updated whenever the estimated model mismatch exceeds predetermined bounds. Based on the redesigned model, an adaptive PID and lead-lag controller will be re-tuned using genetic algorithm (GA). The optimization problems are formulated to increase the damping ratio and place the dominant mode in a D-shape region. The GA is applied to solve the optimization problem and to achieve control parameters. The performance of the proposed adaptive controller has been investigated in a hybrid wind-diesel power system in comparison with conventional controller. Simulation results confirm that damping effect of the proposed adaptive controllers are much better that of the conventional controllers against various operating.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129514849","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 : 2012-12-01DOI: 10.1109/POWERCON.2012.6401353
Le-Ren Chang-Chien, L. An, Ta-Wei Lin
In the proposed frequency restoration plan, demand response is adopted as the first shedding option for intercepting frequency decline in order to avoid the unexpected load shedding, then followed by the scheduled generation reserve to raise frequency back to the normal state. This paper starts with the frequency response analysis using a low-order frequency response model. Results of the frequency response analysis show that, if the magnitude of system disturbance is accurately estimated following the moment of incident, the estimate could be intelligently used to deploy appropriate demand response for frequency restoration. Tests of the proposed frequency restoration scheme are evaluated by simulation where the system data is utilized by records of historical frequency events from a utility. Test results show that the deployment of the demand response could enhance frequency security under various contingency scenarios.
{"title":"Demand response plan considering available spinning reserve for system frequency restoration","authors":"Le-Ren Chang-Chien, L. An, Ta-Wei Lin","doi":"10.1109/POWERCON.2012.6401353","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401353","url":null,"abstract":"In the proposed frequency restoration plan, demand response is adopted as the first shedding option for intercepting frequency decline in order to avoid the unexpected load shedding, then followed by the scheduled generation reserve to raise frequency back to the normal state. This paper starts with the frequency response analysis using a low-order frequency response model. Results of the frequency response analysis show that, if the magnitude of system disturbance is accurately estimated following the moment of incident, the estimate could be intelligently used to deploy appropriate demand response for frequency restoration. Tests of the proposed frequency restoration scheme are evaluated by simulation where the system data is utilized by records of historical frequency events from a utility. Test results show that the deployment of the demand response could enhance frequency security under various contingency scenarios.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131164390","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 : 2012-12-01DOI: 10.1109/POWERCON.2012.6401336
F. Nomiyama, J. Asai, T. Murakami, H. Takano, J. Murata
Two models are proposed for forecasting global solar radiation. The forecasted values are used to predict the output power of photovoltaic systems installed in power systems and control the output of other generators to meet the electricity demand. One of the models is used for at least one-day-ahead demand and supply planning. The other model is used for three-hour-ahead demand and supply operation. The models are based on weather information and use descriptive statistics and binary trees respectively. The focus is on estimation of the anticipated variations in the forecasts and dealing with the nonlinearity of the relationship between the global solar radiation and the input variables. In addition, the smoothing effect of the errors is investigated and utilized when they are applied to wide area forecasting. The results show that they are promising in keeping the balance between demand and supply in power systems with photovoltaic systems installed.
{"title":"A study on global solar radiation forecasting models using meteorological data and their application to wide area forecast","authors":"F. Nomiyama, J. Asai, T. Murakami, H. Takano, J. Murata","doi":"10.1109/POWERCON.2012.6401336","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401336","url":null,"abstract":"Two models are proposed for forecasting global solar radiation. The forecasted values are used to predict the output power of photovoltaic systems installed in power systems and control the output of other generators to meet the electricity demand. One of the models is used for at least one-day-ahead demand and supply planning. The other model is used for three-hour-ahead demand and supply operation. The models are based on weather information and use descriptive statistics and binary trees respectively. The focus is on estimation of the anticipated variations in the forecasts and dealing with the nonlinearity of the relationship between the global solar radiation and the input variables. In addition, the smoothing effect of the errors is investigated and utilized when they are applied to wide area forecasting. The results show that they are promising in keeping the balance between demand and supply in power systems with photovoltaic systems installed.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117134358","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 : 2012-12-01DOI: 10.1109/POWERCON.2012.6401448
M. Tariq, Z. Zhou, J. Wu, M. Macuha, T. Sato
The involvement of smart grid in home and building automation systems has led to the development of diverse standards for interoperable products to control appliances, lighting, energy management and security. Smart grid enables a user to control the energy usage according to the price and demand. These standards have been developed in parallel by different organizations, which are either open or proprietary. It is necessary to arrange these standards in such a way that it is easier for potential readers to easily understand and select a suitable standard according to their functionalities without going into the depth of each standard. In this paper, we review the main smart grid standards proposed by different organizations for home and building automation in terms of different function fields. In addition, we evaluate the scope of interoperability, benefits and drawbacks of the standard.
{"title":"Smart grid standards for home and building automation","authors":"M. Tariq, Z. Zhou, J. Wu, M. Macuha, T. Sato","doi":"10.1109/POWERCON.2012.6401448","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401448","url":null,"abstract":"The involvement of smart grid in home and building automation systems has led to the development of diverse standards for interoperable products to control appliances, lighting, energy management and security. Smart grid enables a user to control the energy usage according to the price and demand. These standards have been developed in parallel by different organizations, which are either open or proprietary. It is necessary to arrange these standards in such a way that it is easier for potential readers to easily understand and select a suitable standard according to their functionalities without going into the depth of each standard. In this paper, we review the main smart grid standards proposed by different organizations for home and building automation in terms of different function fields. In addition, we evaluate the scope of interoperability, benefits and drawbacks of the standard.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130970392","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 : 2012-10-30DOI: 10.1109/POWERCON.2012.6401288
A. Zahedi, Jun Lu
Solar photovoltaic electricity is more expensive by a large margin compared with conventional electricity at retail level. As a result, general public do not find the solar PV electricity an attractive option to use for generating a portion of their electricity need. To promote PV electricity utilization and to make it more attractive, Governments of some countries like Germany, Japan, USA, Australia, and etc. have introduced solar PV incentive programs. Most of grid-connected photovoltaic (PV) systems on residential or commercial buildings in these countries are installed by individuals interested in generating part of their electricity emission-free. For some of these people the economics of the PV electricity is likely to be of secondary importance, while majority of them would like to see financial return to become interested to use PV electricity. The objective of this paper is to present the results of a study conducted on the economical aspects of solar PV to estimate the electricity price of grid-connected rooftop PV system under climate conditions and geographical location of New Zealand (at latitude of between 35° S to 47° S to, and longitude between 167° E and 180° E) to see if the use of PV electricity is attractive and affordable by residential customers. The results of this study will help to determining an appropriate feed-in tariff for solar PV electricity in New Zealand.
{"title":"Economic evaluation of grid-connected solar PV production cost in New Zealand","authors":"A. Zahedi, Jun Lu","doi":"10.1109/POWERCON.2012.6401288","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401288","url":null,"abstract":"Solar photovoltaic electricity is more expensive by a large margin compared with conventional electricity at retail level. As a result, general public do not find the solar PV electricity an attractive option to use for generating a portion of their electricity need. To promote PV electricity utilization and to make it more attractive, Governments of some countries like Germany, Japan, USA, Australia, and etc. have introduced solar PV incentive programs. Most of grid-connected photovoltaic (PV) systems on residential or commercial buildings in these countries are installed by individuals interested in generating part of their electricity emission-free. For some of these people the economics of the PV electricity is likely to be of secondary importance, while majority of them would like to see financial return to become interested to use PV electricity. The objective of this paper is to present the results of a study conducted on the economical aspects of solar PV to estimate the electricity price of grid-connected rooftop PV system under climate conditions and geographical location of New Zealand (at latitude of between 35° S to 47° S to, and longitude between 167° E and 180° E) to see if the use of PV electricity is attractive and affordable by residential customers. The results of this study will help to determining an appropriate feed-in tariff for solar PV electricity in New Zealand.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131120919","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401385
R. Leelaruji, L. Vanfretti
This article rationalizes the need of coordination between protective systems and VSC-HVDC controls to steer power systems away from voltage instability conditions. The concept of coordination involves the use of feasible communication mechanisms which can be exploited by protection systems to send out a “protective information set” to an algorithm which will determine preventive, corrective, and protective actions particularly by taking advantage of the availability of VSC-HVDC. This “protective information set” considers synchrophasor vector processing capabilities which allows for the exploitation of phasor measurements while satisfying protective relaying data transmission and processing requirements. Coordination refers to the ability of the protective systems and VSC-HVDCs to cooperate and to synchronize their actions so that voltage instability can be avoided.
{"title":"Utilizing synchrophasor-based protection systems with VSC-HVDC controls to mitigate voltage instability","authors":"R. Leelaruji, L. Vanfretti","doi":"10.1109/POWERCON.2012.6401385","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401385","url":null,"abstract":"This article rationalizes the need of coordination between protective systems and VSC-HVDC controls to steer power systems away from voltage instability conditions. The concept of coordination involves the use of feasible communication mechanisms which can be exploited by protection systems to send out a “protective information set” to an algorithm which will determine preventive, corrective, and protective actions particularly by taking advantage of the availability of VSC-HVDC. This “protective information set” considers synchrophasor vector processing capabilities which allows for the exploitation of phasor measurements while satisfying protective relaying data transmission and processing requirements. Coordination refers to the ability of the protective systems and VSC-HVDCs to cooperate and to synchronize their actions so that voltage instability can be avoided.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115311022","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401287
Ango Sobu, Guohong Wu
This paper proposes the dynamic optimal schedule management method for an isolated or grid-connected microgrid system with renewable power generations such as PV systems and wind power systems, and with back-up and storage sources such as micro-turbine generators and electricity storage, which is able to consider forecast errors with uncertainties of solar radiation, wind speed and local user demands. The energy management system (EMS) structure for optimization in terms of the economic and stable operation in the microgrid is proposed. Optimization problem for the power from micro-turbine generators or the grid and electricity storage in EMS is resolved by dynamic programming (DP) and equal incremental fuel cost method. The proposed method is confirmed by case study that used forecast data and realization data of renewable power generations and local user demands. In conclusion, this paper presented a practicable method for the operation of a microgrid.
{"title":"Dynamic optimal schedule management method for microgrid system considering forecast errors of renewable power generations","authors":"Ango Sobu, Guohong Wu","doi":"10.1109/POWERCON.2012.6401287","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401287","url":null,"abstract":"This paper proposes the dynamic optimal schedule management method for an isolated or grid-connected microgrid system with renewable power generations such as PV systems and wind power systems, and with back-up and storage sources such as micro-turbine generators and electricity storage, which is able to consider forecast errors with uncertainties of solar radiation, wind speed and local user demands. The energy management system (EMS) structure for optimization in terms of the economic and stable operation in the microgrid is proposed. Optimization problem for the power from micro-turbine generators or the grid and electricity storage in EMS is resolved by dynamic programming (DP) and equal incremental fuel cost method. The proposed method is confirmed by case study that used forecast data and realization data of renewable power generations and local user demands. In conclusion, this paper presented a practicable method for the operation of a microgrid.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115372319","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401454
P. Basak, S. Chowdhury, S. Chowdhury, S. Halder
This paper presents a study of control techniques required for microgrid operation using Automated Demand Side Management (ADSM) control strategy. The control strategies are very useful for smooth operation of microgrid in different modes highlighting basic control issues to maintain power quality and the pre-set conditions which will determine the connectivity of microgrid with the load and main utility grid. Two control strategies are proposed using Simulink-Matlab based on automated demand side control. The first one is useful to prevent abnormal load growth which considers capacity of real power generation as reference for further addition of load. The second strategy presented for automated demand side control which decides connection of additional load considering total active power loss in distribution system as reference.
{"title":"Automated Demand Side Management (ADSM) strategy of microgrid","authors":"P. Basak, S. Chowdhury, S. Chowdhury, S. Halder","doi":"10.1109/POWERCON.2012.6401454","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401454","url":null,"abstract":"This paper presents a study of control techniques required for microgrid operation using Automated Demand Side Management (ADSM) control strategy. The control strategies are very useful for smooth operation of microgrid in different modes highlighting basic control issues to maintain power quality and the pre-set conditions which will determine the connectivity of microgrid with the load and main utility grid. Two control strategies are proposed using Simulink-Matlab based on automated demand side control. The first one is useful to prevent abnormal load growth which considers capacity of real power generation as reference for further addition of load. The second strategy presented for automated demand side control which decides connection of additional load considering total active power loss in distribution system as reference.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124912348","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401283
F. Crispino, L. Ogiboski, L. A. Murakami, L. Magrini
This paper presents a methodology for evaluating teleprotection system applying statistical process control techniques. The system was installed in a power transmission line at CTEEP (a Brazilian transmission utility), where it was implemented an information acquisition system from protective relays and teleprotection equipment. The information are automatically collected, synchronized by GPS and stored in a database. The objective of the system is to obtain information to be processed through statistical techniques to evaluate teleprotection system performance and conditions, assisting management of teleprotection maintenance.
{"title":"Teleprotection status analysis applying statistical process control techniques","authors":"F. Crispino, L. Ogiboski, L. A. Murakami, L. Magrini","doi":"10.1109/POWERCON.2012.6401283","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401283","url":null,"abstract":"This paper presents a methodology for evaluating teleprotection system applying statistical process control techniques. The system was installed in a power transmission line at CTEEP (a Brazilian transmission utility), where it was implemented an information acquisition system from protective relays and teleprotection equipment. The information are automatically collected, synchronized by GPS and stored in a database. The objective of the system is to obtain information to be processed through statistical techniques to evaluate teleprotection system performance and conditions, assisting management of teleprotection maintenance.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123449312","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 : 2012-10-01DOI: 10.1109/POWERCON.2012.6401433
Yanhua Liu, N. Zhang, Xu Zhang
The micro-grid is an approach to solve distributed generations interconnecting with power grid. Wind-PV-ES hybrid system could make full use of clean energy and have high reliability. Smooth switching between grid-connected and islanding mode is important to micro-grid stable operation. This paper proposes an improved control strategy combining master-slave control with peer-to-peer control in order to make transition between grid-connected and islanding mode smoother. A micro-grid model based on wind-PV-ES hybrid system is built with DigSILENT/PowerFactory, and the improved control strategy is realized on it. The result shows that this improved control strategy can ensure power balance, and keep connected bus voltage and micro-grid frequency stable during micro-grid mode switching.
{"title":"Research on grid-connected/islanding smooth switching of micro-grid based on energy storage","authors":"Yanhua Liu, N. Zhang, Xu Zhang","doi":"10.1109/POWERCON.2012.6401433","DOIUrl":"https://doi.org/10.1109/POWERCON.2012.6401433","url":null,"abstract":"The micro-grid is an approach to solve distributed generations interconnecting with power grid. Wind-PV-ES hybrid system could make full use of clean energy and have high reliability. Smooth switching between grid-connected and islanding mode is important to micro-grid stable operation. This paper proposes an improved control strategy combining master-slave control with peer-to-peer control in order to make transition between grid-connected and islanding mode smoother. A micro-grid model based on wind-PV-ES hybrid system is built with DigSILENT/PowerFactory, and the improved control strategy is realized on it. The result shows that this improved control strategy can ensure power balance, and keep connected bus voltage and micro-grid frequency stable during micro-grid mode switching.","PeriodicalId":176214,"journal":{"name":"2012 IEEE International Conference on Power System Technology (POWERCON)","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116034338","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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