Pub Date : 1900-01-01DOI: 10.1109/IPEC.2005.207036
W. Sae-Kok, A. Yokoyama, T. Nitta
High response excitation type superconducting generator has various advantages such as high efficiency, small size, light weight, including the low synchronous reactance yielding in improvement of power system stability. In addition, it also has a particular characteristic due to its structure, called SMES effect; it can enables rapid changes and the excitation power will be large and have a rapid change enough to affect the conditions of power system in self-excited operation of the generator. In this paper, energy function, which is commonly used for transient stability evaluation, is considered in designing the excitation control system for high response excitation type superconducting generator in order to improve the power system dynamics; SMES effect is taken into account in the control design so as to be used effectively for stability improvement. The control performance is examined in IEEJ East 10-machine model system
高响应励磁式超导发电机具有效率高、体积小、重量轻、同步电抗屈服小等优点，对提高电力系统的稳定性具有重要意义。此外，由于其结构，它还有一个特殊的特点，称为中小企业效应;它可以实现快速变化，励磁功率大且变化快，足以影响发电机自激运行时电力系统的状况。本文在设计高响应励磁型超导发电机励磁控制系统时，考虑了暂态稳定评价中常用的能量函数，以改善电力系统的动力学特性;在控制设计中考虑了中小企业效应，从而有效地提高了稳定性。在IEEJ East 10机模型系统中测试了控制性能
{"title":"Energy function based controllers of superconducting generators with high response excitation","authors":"W. Sae-Kok, A. Yokoyama, T. Nitta","doi":"10.1109/IPEC.2005.207036","DOIUrl":"https://doi.org/10.1109/IPEC.2005.207036","url":null,"abstract":"High response excitation type superconducting generator has various advantages such as high efficiency, small size, light weight, including the low synchronous reactance yielding in improvement of power system stability. In addition, it also has a particular characteristic due to its structure, called SMES effect; it can enables rapid changes and the excitation power will be large and have a rapid change enough to affect the conditions of power system in self-excited operation of the generator. In this paper, energy function, which is commonly used for transient stability evaluation, is considered in designing the excitation control system for high response excitation type superconducting generator in order to improve the power system dynamics; SMES effect is taken into account in the control design so as to be used effectively for stability improvement. The control performance is examined in IEEJ East 10-machine model system","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121254019","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 : 1900-01-01DOI: 10.1109/IPEC.2005.206872
T. K. Sengupta, A. Das, A. Mukhopadhya
In this paper an attempt has been made for measurement of frequency and development of frequency protection relay by simulation in a PC. System has also been developed to interface the HV/EHV power system with the PC. Development of the measurement process and also the relay has been simulated with software Simulink (Matlabtrade). For interfacing at the input, a set of hardware has been used. The output signal is generated from the analog output block of the relay unit and finally sent to the LPT1 port of the PC. The generated output signal, which sends the trip signal to the parallel port, is interfaced to the physical system. Through "digital to analog converter (DAC 0804)" the signal turns to an analogue signal. This signal further amplified and is used for monitoring, control and protection of the equipment depending on different frequency range and the logical condition framed in elements of the relay unit
{"title":"Development of on-line real-time PC based frequency meter and frequency relay for monitoring, control and protection of HV/ EHV power system","authors":"T. K. Sengupta, A. Das, A. Mukhopadhya","doi":"10.1109/IPEC.2005.206872","DOIUrl":"https://doi.org/10.1109/IPEC.2005.206872","url":null,"abstract":"In this paper an attempt has been made for measurement of frequency and development of frequency protection relay by simulation in a PC. System has also been developed to interface the HV/EHV power system with the PC. Development of the measurement process and also the relay has been simulated with software Simulink (Matlabtrade). For interfacing at the input, a set of hardware has been used. The output signal is generated from the analog output block of the relay unit and finally sent to the LPT1 port of the PC. The generated output signal, which sends the trip signal to the parallel port, is interfaced to the physical system. Through \"digital to analog converter (DAC 0804)\" the signal turns to an analogue signal. This signal further amplified and is used for monitoring, control and protection of the equipment depending on different frequency range and the logical condition framed in elements of the relay unit","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124894110","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 : 1900-01-01DOI: 10.1109/IPEC.2005.207024
C. Thammarat, S. Tadsuan, B. Suechoey, S. Bunjongjit
The purpose of this research is to study the power loss generating of the PWM inverter and the 1 HP 380 V 3-phase squirrel cage induction motor. The test procedure was performed by varying fundamental frequency in the range 25-50 Hz and at constant 1.5 kHz - PWM inverter switching frequency, as a source to the 3-phase 380 V squirrel cage induction motor in star connection with 5.1 N.m constant torque load. The test analysis was to record the input/output voltage/current waveforms by using YOKOGAWA DL1640 storage oscilloscope. Then, using the function FFT program was to determine the variety parameters at each harmonic from those waveforms. The total power loss and efficiency a were calculated by those parameters. The results show the input power is minimum at 25 Hz fundamental frequency and maximum at 50 Hz. But the efficiency is minimum at 25 Hz fundamental frequency and maximum at 50 Hz. The minimum motor power loss is at 35-40 Hz fundamental frequency and the maximum inverter power loss at 81-85% efficiency is around 25-50 Hz fundamental frequency. And also, this is the useful information in designed inverter process to extend the motor' life due to the overheat from power loss
{"title":"The result analysis of the power loss 3-phase induction motor with PWM inverter supply","authors":"C. Thammarat, S. Tadsuan, B. Suechoey, S. Bunjongjit","doi":"10.1109/IPEC.2005.207024","DOIUrl":"https://doi.org/10.1109/IPEC.2005.207024","url":null,"abstract":"The purpose of this research is to study the power loss generating of the PWM inverter and the 1 HP 380 V 3-phase squirrel cage induction motor. The test procedure was performed by varying fundamental frequency in the range 25-50 Hz and at constant 1.5 kHz - PWM inverter switching frequency, as a source to the 3-phase 380 V squirrel cage induction motor in star connection with 5.1 N.m constant torque load. The test analysis was to record the input/output voltage/current waveforms by using YOKOGAWA DL1640 storage oscilloscope. Then, using the function FFT program was to determine the variety parameters at each harmonic from those waveforms. The total power loss and efficiency a were calculated by those parameters. The results show the input power is minimum at 25 Hz fundamental frequency and maximum at 50 Hz. But the efficiency is minimum at 25 Hz fundamental frequency and maximum at 50 Hz. The minimum motor power loss is at 35-40 Hz fundamental frequency and the maximum inverter power loss at 81-85% efficiency is around 25-50 Hz fundamental frequency. And also, this is the useful information in designed inverter process to extend the motor' life due to the overheat from power loss","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125939634","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 : 1900-01-01DOI: 10.1109/IPEC.2005.207075
Mao Anjia, Yue Jiaxi, Guo Zhizhong
Secure and reliable operation of power system is significant for nation's economy development and society stability. To ascertain this, analysis and calculation plays an important role. Power system calculations can be classified into three categories in time domain: for the past, for the present and for the future respectively. And the calculations for the future seem to be more significant to support power system operation and make production arrangement. However, almost all the calculations of power system are based on the mathematic models established from the physical system; and the models may have various errors and mismatch the actual system, especially for the calculations facing the future. The mismatch between calculation model and actual system influences the analysis result and the operation of power system. In this paper, the influence of two kinds of model mismatches injection mismatch and grid structure mismatch on the actual system are analyzed for power flow calculation using matrix analysis method. The results show that the calculation errors of injection parameter mismatch are approximately linear to the mismatch quantities, and the calculation errors of grid structure mismatch are closely related to the admittance of the mismatching branch and the phase-angle difference of its node voltage. Because the mismatch between calculation model and real system always exists, so this paper also suggests that we should depend more on measurements rather than calculation models in power system analysis
{"title":"The influence of model mismatch to power system calculation, part I: on the steady state calculation","authors":"Mao Anjia, Yue Jiaxi, Guo Zhizhong","doi":"10.1109/IPEC.2005.207075","DOIUrl":"https://doi.org/10.1109/IPEC.2005.207075","url":null,"abstract":"Secure and reliable operation of power system is significant for nation's economy development and society stability. To ascertain this, analysis and calculation plays an important role. Power system calculations can be classified into three categories in time domain: for the past, for the present and for the future respectively. And the calculations for the future seem to be more significant to support power system operation and make production arrangement. However, almost all the calculations of power system are based on the mathematic models established from the physical system; and the models may have various errors and mismatch the actual system, especially for the calculations facing the future. The mismatch between calculation model and actual system influences the analysis result and the operation of power system. In this paper, the influence of two kinds of model mismatches injection mismatch and grid structure mismatch on the actual system are analyzed for power flow calculation using matrix analysis method. The results show that the calculation errors of injection parameter mismatch are approximately linear to the mismatch quantities, and the calculation errors of grid structure mismatch are closely related to the admittance of the mismatching branch and the phase-angle difference of its node voltage. Because the mismatch between calculation model and real system always exists, so this paper also suggests that we should depend more on measurements rather than calculation models in power system analysis","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126123879","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 : 1900-01-01DOI: 10.1109/IPEC.2005.207038
Hongying Li, Youyi Wang
Application of nonlinear robust decentralized control method using linear matrix inequality (LMl) approach in a multimachine environment is described in this paper. The proposed approach is evaluated by a five-machine power system model without infinite bus. The feedback gain of each generator is obtained by solving a set of LMIs based on the bounds of the machine parameters. The resulting guaranteed cost controller is valid within a wide range of operation conditions. Simulation tests and results show that the designed controller is effective despite the interconnections among generators, different operation points and fault locations of the multimachine systems
{"title":"Nonlinear robust decentralized control of multimachine power systems","authors":"Hongying Li, Youyi Wang","doi":"10.1109/IPEC.2005.207038","DOIUrl":"https://doi.org/10.1109/IPEC.2005.207038","url":null,"abstract":"Application of nonlinear robust decentralized control method using linear matrix inequality (LMl) approach in a multimachine environment is described in this paper. The proposed approach is evaluated by a five-machine power system model without infinite bus. The feedback gain of each generator is obtained by solving a set of LMIs based on the bounds of the machine parameters. The resulting guaranteed cost controller is valid within a wide range of operation conditions. Simulation tests and results show that the designed controller is effective despite the interconnections among generators, different operation points and fault locations of the multimachine systems","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114386879","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 : 1900-01-01DOI: 10.1109/IPEC.2005.206875
Jingfei Yang, J. Stenzel
Short-term load forecasting (STLF) is a significant task for power system operation. The existence of bad data in historical load curve affects the precision of load forecasting result. This paper presents the second order difference method to detect the bad data, eliminate them and evaluate the real data. To decrease the effect of impulse load on the prediction result, weighted least square quadratic fitting is proposed to filter the curve. K-means clustering and support vector machine method are employed to forecast the future load. The proposed method is successfully applied to an actual power system
{"title":"Historical load curve correction for short-term load forecasting","authors":"Jingfei Yang, J. Stenzel","doi":"10.1109/IPEC.2005.206875","DOIUrl":"https://doi.org/10.1109/IPEC.2005.206875","url":null,"abstract":"Short-term load forecasting (STLF) is a significant task for power system operation. The existence of bad data in historical load curve affects the precision of load forecasting result. This paper presents the second order difference method to detect the bad data, eliminate them and evaluate the real data. To decrease the effect of impulse load on the prediction result, weighted least square quadratic fitting is proposed to filter the curve. K-means clustering and support vector machine method are employed to forecast the future load. The proposed method is successfully applied to an actual power system","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117095306","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 : 1900-01-01DOI: 10.1109/IPEC.2005.206979
Ming-yu Yang, Wan-Ye Yao, Zengping Wang, Yanjun Jiao, Ju Zhang
A new non-unit voltage protection algorithm for extra high voltage (EHV) transmission lines is presented in this paper. The singularity of fault transient voltage signals in one terminal is utilized to discriminate clearly between internal and external faults. Lipschitz exponent (LE) is obtained from wavelet modulus maximum to detect singularity of signals. A typical 500 kV EHV transmission system has been simulated by ATP to evaluate the scheme. The simulation results show that this scheme is capable of providing correct responses under various system configurations and fault conditions
{"title":"A new protection algorithm for EHV transmission line based on singularity detection of fault transient voltage","authors":"Ming-yu Yang, Wan-Ye Yao, Zengping Wang, Yanjun Jiao, Ju Zhang","doi":"10.1109/IPEC.2005.206979","DOIUrl":"https://doi.org/10.1109/IPEC.2005.206979","url":null,"abstract":"A new non-unit voltage protection algorithm for extra high voltage (EHV) transmission lines is presented in this paper. The singularity of fault transient voltage signals in one terminal is utilized to discriminate clearly between internal and external faults. Lipschitz exponent (LE) is obtained from wavelet modulus maximum to detect singularity of signals. A typical 500 kV EHV transmission system has been simulated by ATP to evaluate the scheme. The simulation results show that this scheme is capable of providing correct responses under various system configurations and fault conditions","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129500601","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 : 1900-01-01DOI: 10.1109/IPEC.2005.206946
Zheng Hua, Xie Li, Zhang Li-zi
In electricity market, it is widely accepted that short-term load forecast is a key problem of market operation. In this paper, a novel model for load forecasting based on intelligence information processing is presented. Here, we make full use of the excellent property reconstruction ability of independent component analysis, which is a new intelligence information processing technology for separating signals and making them independent mutually, and presents STLF model based independent property reconstruction. The load properties of different kinds are restructured to enhance its representation ability and simplifying STLF modeling by ANN. After neural network is trained by new properties with lower dimension, STLF model is built. Finally, the real load data of spot market in New England is applied to demonstrate the validity of the proposed approach
{"title":"Load forecasting based on intelligence information processing","authors":"Zheng Hua, Xie Li, Zhang Li-zi","doi":"10.1109/IPEC.2005.206946","DOIUrl":"https://doi.org/10.1109/IPEC.2005.206946","url":null,"abstract":"In electricity market, it is widely accepted that short-term load forecast is a key problem of market operation. In this paper, a novel model for load forecasting based on intelligence information processing is presented. Here, we make full use of the excellent property reconstruction ability of independent component analysis, which is a new intelligence information processing technology for separating signals and making them independent mutually, and presents STLF model based independent property reconstruction. The load properties of different kinds are restructured to enhance its representation ability and simplifying STLF modeling by ANN. After neural network is trained by new properties with lower dimension, STLF model is built. Finally, the real load data of spot market in New England is applied to demonstrate the validity of the proposed approach","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129524625","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 : 1900-01-01DOI: 10.1109/IPEC.2005.206956
P. Dash, S. Samantaray, G. Panda
The S-transform (ST) is an extension of wavelet transform which possesses superior property over the latter as the moving functions are fixed with respect to time axis while the localizing scalable Gaussian window dilates and translates. Phase spectrum obtained in this transform is always with respect to fixed reference point and the real and imaginary spectrum can be localized independently. Such a transform with moving and scalable localizing Gaussian window, therefore, provides excellent time localization property for different signals. Utilizing the ST fault current signal is analyzed for an advanced series compensated transmission system. The spectral analysis of the current signals at different fault conditions of the system clearly classifies the faulty phase and faulty section
{"title":"Fault analysis of advanced series compensated line using S-transform and pattern recognition approach","authors":"P. Dash, S. Samantaray, G. Panda","doi":"10.1109/IPEC.2005.206956","DOIUrl":"https://doi.org/10.1109/IPEC.2005.206956","url":null,"abstract":"The S-transform (ST) is an extension of wavelet transform which possesses superior property over the latter as the moving functions are fixed with respect to time axis while the localizing scalable Gaussian window dilates and translates. Phase spectrum obtained in this transform is always with respect to fixed reference point and the real and imaginary spectrum can be localized independently. Such a transform with moving and scalable localizing Gaussian window, therefore, provides excellent time localization property for different signals. Utilizing the ST fault current signal is analyzed for an advanced series compensated transmission system. The spectral analysis of the current signals at different fault conditions of the system clearly classifies the faulty phase and faulty section","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129081427","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 : 1900-01-01DOI: 10.1109/IPEC.2005.207115
R. Lahiri, P. Banerjee, S. Cgowdhury, A. Saha, S. Chowdhury
This paper deals with "reorganization of Assam State Electricity Board" by disaggregation of the Assam State Electricity Board into five distinct corporations (generation, transmission and three distribution companies) to support government of Assam in restructuring it and in developing strategies for new companies to operate in an efficient and commercial manner so that the sector can become financially viable. As the reforms progresses the companies may need process improvements, which requires benchmarking the current processes with the best in industry and implementation of those process improvements. The task is to identify the key performance indicators (KPIs) for each of these processes, to establish targets and to link them to overall financial performance of new companies. The objective is that the new companies are able to deliver the strategy in the changed environment
{"title":"Process improvement in distribution for reorganization of a state electricity board","authors":"R. Lahiri, P. Banerjee, S. Cgowdhury, A. Saha, S. Chowdhury","doi":"10.1109/IPEC.2005.207115","DOIUrl":"https://doi.org/10.1109/IPEC.2005.207115","url":null,"abstract":"This paper deals with \"reorganization of Assam State Electricity Board\" by disaggregation of the Assam State Electricity Board into five distinct corporations (generation, transmission and three distribution companies) to support government of Assam in restructuring it and in developing strategies for new companies to operate in an efficient and commercial manner so that the sector can become financially viable. As the reforms progresses the companies may need process improvements, which requires benchmarking the current processes with the best in industry and implementation of those process improvements. The task is to identify the key performance indicators (KPIs) for each of these processes, to establish targets and to link them to overall financial performance of new companies. The objective is that the new companies are able to deliver the strategy in the changed environment","PeriodicalId":164802,"journal":{"name":"2005 International Power Engineering Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130578751","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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