Pub Date : 2002-08-07DOI: 10.1109/PESW.2002.985224
Y. Liu, M. Rothleder, Z. Alaywan, M. Assadian, F. Rahimi
A cost-minimizing algorithm (called Rational Buyer's algorithm) has been in production since August 1999 at the California ISO. Two years of real-time operation results have shown significant savings in overall cost of ancillary services procurement. By allowing ISO to procure higher quality services to meet the demand for lower quality services, when doing so reduces the overall procurement cost, the Rational Buyer's algorithm minimizes the total cost of procuring ancillary services under the market rules. The minimum-cost procurement is found by a search through the domain defined by the market and cost-minimizing rules. While the theory behind the algorithm is very straightforward, the implementation of the algorithm has been a challenge. In this paper, a few key issues in implementing the algorithm as well as the operational experiences on the ancillary services market at the California ISO are introduced.
{"title":"Implementing Rational Buyer's algorithm at California ISO","authors":"Y. Liu, M. Rothleder, Z. Alaywan, M. Assadian, F. Rahimi","doi":"10.1109/PESW.2002.985224","DOIUrl":"https://doi.org/10.1109/PESW.2002.985224","url":null,"abstract":"A cost-minimizing algorithm (called Rational Buyer's algorithm) has been in production since August 1999 at the California ISO. Two years of real-time operation results have shown significant savings in overall cost of ancillary services procurement. By allowing ISO to procure higher quality services to meet the demand for lower quality services, when doing so reduces the overall procurement cost, the Rational Buyer's algorithm minimizes the total cost of procuring ancillary services under the market rules. The minimum-cost procurement is found by a search through the domain defined by the market and cost-minimizing rules. While the theory behind the algorithm is very straightforward, the implementation of the algorithm has been a challenge. In this paper, a few key issues in implementing the algorithm as well as the operational experiences on the ancillary services market at the California ISO are introduced.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121754791","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 : 2002-08-07DOI: 10.1109/PESW.2002.985120
L. L. Lai
Summary form only given. Power quality has become an important concern both to utilities and their customers with wide spread use of electronic and power electronic equipment. Power quality embraces problems caused by harmonics, over or undervoltages, or supply discontinuities. To improve the electric power quality, sources of disturbances must be known and controlled. This paper reports a new method, which does not have the limitations as mentioned previously. The new method is based on wavelets. Current waveforms of typical loads on the power system are sampled and converted into a sequence of digital values. A discrete wavelet transform is then applied to these values. In this way, the authors have been able to find out the different types of load that contributes electric power harmonics to the power system. Encouraging results have been obtained and are presented in the paper.
{"title":"Wavelet-based neural network for power quality recognition","authors":"L. L. Lai","doi":"10.1109/PESW.2002.985120","DOIUrl":"https://doi.org/10.1109/PESW.2002.985120","url":null,"abstract":"Summary form only given. Power quality has become an important concern both to utilities and their customers with wide spread use of electronic and power electronic equipment. Power quality embraces problems caused by harmonics, over or undervoltages, or supply discontinuities. To improve the electric power quality, sources of disturbances must be known and controlled. This paper reports a new method, which does not have the limitations as mentioned previously. The new method is based on wavelets. Current waveforms of typical loads on the power system are sampled and converted into a sequence of digital values. A discrete wavelet transform is then applied to these values. In this way, the authors have been able to find out the different types of load that contributes electric power harmonics to the power system. Encouraging results have been obtained and are presented in the paper.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133960196","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 : 2002-08-07DOI: 10.1109/PESW.2002.985233
R. Ishino
A thermal image has often been used to inspect a power distribution apparatus. The development of an automatic diagnosis method for the apparatus, which utilizes thermal images, will facilitate the inspection. To this end, a new method of diagnosing a power distribution apparatus by means of thermal images has been developed as one of the functions incorporated into a monitoring device that moves on an overhead ground wire. The method consists of both extraction of the apparatus from a thermal image and diagnosis of the apparatus in terms of the local temperature gradient. Experiments using the proposed method were conducted under different weather conditions, times, and seasons. An error rate of 3% was obtained from the experiments on the extraction of apparatus, and an error rate of 17% was obtained from the experiments on the detection of faulty apparatus. The proposed method can extract and detect faulty apparatuses except the case in which the distance between the pole and the infrared camera is so large that the sensitivity is insufficient.
{"title":"Detection of a faulty power distribution apparatus by using thermal images","authors":"R. Ishino","doi":"10.1109/PESW.2002.985233","DOIUrl":"https://doi.org/10.1109/PESW.2002.985233","url":null,"abstract":"A thermal image has often been used to inspect a power distribution apparatus. The development of an automatic diagnosis method for the apparatus, which utilizes thermal images, will facilitate the inspection. To this end, a new method of diagnosing a power distribution apparatus by means of thermal images has been developed as one of the functions incorporated into a monitoring device that moves on an overhead ground wire. The method consists of both extraction of the apparatus from a thermal image and diagnosis of the apparatus in terms of the local temperature gradient. Experiments using the proposed method were conducted under different weather conditions, times, and seasons. An error rate of 3% was obtained from the experiments on the extraction of apparatus, and an error rate of 17% was obtained from the experiments on the detection of faulty apparatus. The proposed method can extract and detect faulty apparatuses except the case in which the distance between the pole and the infrared camera is so large that the sensitivity is insufficient.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133978655","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 : 2002-08-07DOI: 10.1109/PESW.2002.985144
A. Prudenzi
The paper illustrates an artificial neural network (ANN) based procedure for the identification of pattern-of-use of some main domestic electric appliances from daily profiles of energy recordings taken at household's meter panel at 15 minute steps. The paper describes the architecture used which is structured into multiple subsequent stages based on ANNs. The application of the procedure to some real daily load diagrams as recorded at few household meters demonstrates the efficiency of the proposed approach. The utility of ANNs for extracting further useful information concerning energy usage from data bases typically available for electric companies is finally discussed.
{"title":"A neuron nets based procedure for identifying domestic appliances pattern-of-use from energy recordings at meter panel","authors":"A. Prudenzi","doi":"10.1109/PESW.2002.985144","DOIUrl":"https://doi.org/10.1109/PESW.2002.985144","url":null,"abstract":"The paper illustrates an artificial neural network (ANN) based procedure for the identification of pattern-of-use of some main domestic electric appliances from daily profiles of energy recordings taken at household's meter panel at 15 minute steps. The paper describes the architecture used which is structured into multiple subsequent stages based on ANNs. The application of the procedure to some real daily load diagrams as recorded at few household meters demonstrates the efficiency of the proposed approach. The utility of ANNs for extracting further useful information concerning energy usage from data bases typically available for electric companies is finally discussed.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131848880","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 : 2002-08-07DOI: 10.1109/PESW.2002.985107
Hyungchul Kim, C. Singh
This paper proposes a new probabilistic method involving transient stability and voltage stability for power system security assessment by combining Monte Carlo simulation and self organizing map (SOM). This overcomes the problem of large amount of computation time required for Monte Carlo simulation. SOM learns to recognize groups of similar input vectors in such a way that neurons physically near each other in the neuron layer respond to similar input vectors. Data classification by SOM can reduce sampling data, which reduces computation time for the reliability security index when using classified data. A case study of the IEEE RTS is given to demonstrate the efficiency of this approach.
{"title":"Probabilistic security analysis using SOM and Monte Carlo simulation","authors":"Hyungchul Kim, C. Singh","doi":"10.1109/PESW.2002.985107","DOIUrl":"https://doi.org/10.1109/PESW.2002.985107","url":null,"abstract":"This paper proposes a new probabilistic method involving transient stability and voltage stability for power system security assessment by combining Monte Carlo simulation and self organizing map (SOM). This overcomes the problem of large amount of computation time required for Monte Carlo simulation. SOM learns to recognize groups of similar input vectors in such a way that neurons physically near each other in the neuron layer respond to similar input vectors. Data classification by SOM can reduce sampling data, which reduces computation time for the reliability security index when using classified data. A case study of the IEEE RTS is given to demonstrate the efficiency of this approach.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134436889","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 : 2002-08-07DOI: 10.1109/PESW.2002.984987
Feng Tu, A. Flueck
This paper presents a parallel direct linear solver based on a message-passing distributed-memory multiprocessor architecture such as a cluster of workstations. The results show that the new algorithm can achieve nearly linear speedup for two large-scale power system cases on a small cluster of GNU/Linux dual-processor workstations. The workstations are connected via 100 Mbit/s Ethernet, i.e., the parallel machine consists of hardware readily found in any engineering department. Based on the presented parallel direct linear solver, it is possible to parallelize totally the Newton power flow solution process. In addition, the METIS-based partitioning scheme can handle common control devices such as PV-PQ switching. Furthermore, by tuning the vertex and branch weights, the performance of the power flow solution can be optimized for the available hardware. For a workstation cluster on 100 Mbit/s Ethernet, the speedup appears to saturate beyond eight processors due to load imbalance and the aggregate growth of the partition separators. Nevertheless, the message-passing distributed-memory multiprocessor architecture can be used in other power system applications, such as state estimation and transient stability. Furthermore, an iterative linear solver could improve scalability.
{"title":"A message-passing distributed-memory parallel power flow algorithm","authors":"Feng Tu, A. Flueck","doi":"10.1109/PESW.2002.984987","DOIUrl":"https://doi.org/10.1109/PESW.2002.984987","url":null,"abstract":"This paper presents a parallel direct linear solver based on a message-passing distributed-memory multiprocessor architecture such as a cluster of workstations. The results show that the new algorithm can achieve nearly linear speedup for two large-scale power system cases on a small cluster of GNU/Linux dual-processor workstations. The workstations are connected via 100 Mbit/s Ethernet, i.e., the parallel machine consists of hardware readily found in any engineering department. Based on the presented parallel direct linear solver, it is possible to parallelize totally the Newton power flow solution process. In addition, the METIS-based partitioning scheme can handle common control devices such as PV-PQ switching. Furthermore, by tuning the vertex and branch weights, the performance of the power flow solution can be optimized for the available hardware. For a workstation cluster on 100 Mbit/s Ethernet, the speedup appears to saturate beyond eight processors due to load imbalance and the aggregate growth of the partition separators. Nevertheless, the message-passing distributed-memory multiprocessor architecture can be used in other power system applications, such as state estimation and transient stability. Furthermore, an iterative linear solver could improve scalability.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115804868","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 : 2002-08-07DOI: 10.1109/PESW.2002.985241
T. Nagata, K. Hirai, S. Iwasaki, Y. Ebisawa
In this paper the discussions on the on-load vibration of transformer windings are presented. Firstly, the vibration of the windings was investigated on the 6 kVA model coil both experimentally and analytically. On the on-load condition, the axial vibration of conductors was measured by the accelerometers. Numerical analysis was also conducted on the model coil. The electromagnetic force was calculated by a conventional mirror method. The steady state response of the windings was estimated by the finite element analysis. The calculated result showed fairly good agreement with the measurement and the validity of the numerical method was affirmed. Finally, the vibrations of the full-scale transformer windings were estimated with the same calculation method.
{"title":"Estimation on on-load vibration of transformer windings","authors":"T. Nagata, K. Hirai, S. Iwasaki, Y. Ebisawa","doi":"10.1109/PESW.2002.985241","DOIUrl":"https://doi.org/10.1109/PESW.2002.985241","url":null,"abstract":"In this paper the discussions on the on-load vibration of transformer windings are presented. Firstly, the vibration of the windings was investigated on the 6 kVA model coil both experimentally and analytically. On the on-load condition, the axial vibration of conductors was measured by the accelerometers. Numerical analysis was also conducted on the model coil. The electromagnetic force was calculated by a conventional mirror method. The steady state response of the windings was estimated by the finite element analysis. The calculated result showed fairly good agreement with the measurement and the validity of the numerical method was affirmed. Finally, the vibrations of the full-scale transformer windings were estimated with the same calculation method.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125032502","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 : 2002-08-07DOI: 10.1109/PESW.2002.985195
I. Kamwa, D. Lefebvre, L. Loud
The paper describes a transient stability program (TSP) based approach to identify numerically, a state-space, small-signal model of the open-loop system seen by the hydro-turbine governor during its normal operation. This single-input multiple-output model is validated successfully by comparing actual closed-loop responses computed in the TSP with those simulated in Matlab using the linearized model. For illustration, three governing systems found in the Hydro-Quebec's grid are studied: (1) a mechanical hydraulic; (2) a Woodward PID; and (3) a classical Neyrpic's governor. System performance with respect to the speed of response, interarea modes sensitivity and closed-loop gain and phase margins is assessed, evidencing the somewhat detrimental impact of the derivative control term for interconnected operation. Overall, the small-signal analysis approach devised appears well-suited for determining and/or assessing unit-connected settings of hydro-turbine speed governing systems.
{"title":"Small signal analysis of hydro-turbine governors in large interconnected power plants","authors":"I. Kamwa, D. Lefebvre, L. Loud","doi":"10.1109/PESW.2002.985195","DOIUrl":"https://doi.org/10.1109/PESW.2002.985195","url":null,"abstract":"The paper describes a transient stability program (TSP) based approach to identify numerically, a state-space, small-signal model of the open-loop system seen by the hydro-turbine governor during its normal operation. This single-input multiple-output model is validated successfully by comparing actual closed-loop responses computed in the TSP with those simulated in Matlab using the linearized model. For illustration, three governing systems found in the Hydro-Quebec's grid are studied: (1) a mechanical hydraulic; (2) a Woodward PID; and (3) a classical Neyrpic's governor. System performance with respect to the speed of response, interarea modes sensitivity and closed-loop gain and phase margins is assessed, evidencing the somewhat detrimental impact of the derivative control term for interconnected operation. Overall, the small-signal analysis approach devised appears well-suited for determining and/or assessing unit-connected settings of hydro-turbine speed governing systems.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132422167","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 : 2002-08-07DOI: 10.1109/PESW.2002.985191
Y. Chung
This paper describes a hybrid transfer switch (HTS) made up of the solid-state switches and the high-speed mechanical switches in parallel. In the proposed HTS, the solid-state switches can be turned off and turned on at any given instant so that the transfer time can be minimized under all kinds of power line disturbances. Also the solid-state switches are bypassed during steady-state operation by the mechanical switch, and only conducted during a transfer or other such operation. This eliminates the need for any type of cooling equipment for the solid-state switches. Three different control concepts for the solid-state switches are given and compared through the computer simulations. Experimental equipment was designed and built with a solid-state AC switch, composed of 20 IGBTs in series and 5 IGBTs in parallel, rated to 11 kV/sub RMS//125 A. Experimental results are given for the series connected solid-state switches. Finally conclusions are given.
{"title":"Medium voltage hybrid transfer switch","authors":"Y. Chung","doi":"10.1109/PESW.2002.985191","DOIUrl":"https://doi.org/10.1109/PESW.2002.985191","url":null,"abstract":"This paper describes a hybrid transfer switch (HTS) made up of the solid-state switches and the high-speed mechanical switches in parallel. In the proposed HTS, the solid-state switches can be turned off and turned on at any given instant so that the transfer time can be minimized under all kinds of power line disturbances. Also the solid-state switches are bypassed during steady-state operation by the mechanical switch, and only conducted during a transfer or other such operation. This eliminates the need for any type of cooling equipment for the solid-state switches. Three different control concepts for the solid-state switches are given and compared through the computer simulations. Experimental equipment was designed and built with a solid-state AC switch, composed of 20 IGBTs in series and 5 IGBTs in parallel, rated to 11 kV/sub RMS//125 A. Experimental results are given for the series connected solid-state switches. Finally conclusions are given.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131499508","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 : 2002-08-07DOI: 10.1109/PESW.2002.984994
Yuan Zhou, V. Ajjarapu
This paper provides a unified framework to identify and trace voltage as well as oscillatory stability margin boundaries. The system load margin is traced for any control configuration without tracing the entire PV curve. The eigenvalue calculation associated with Hopf bifurcation is avoided.
{"title":"Identification and tracing of voltage and oscillatory stability margins","authors":"Yuan Zhou, V. Ajjarapu","doi":"10.1109/PESW.2002.984994","DOIUrl":"https://doi.org/10.1109/PESW.2002.984994","url":null,"abstract":"This paper provides a unified framework to identify and trace voltage as well as oscillatory stability margin boundaries. The system load margin is traced for any control configuration without tracing the entire PV curve. The eigenvalue calculation associated with Hopf bifurcation is avoided.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122299255","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：