{"title":"Partial Least-Squares Regression Based Harmonic Emission Level Assessing at the Point of Common Coupling","authors":"Xu Yonghai, Huang Shun, L. Yingying","doi":"10.1109/ICPST.2006.321428","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321428","url":null,"abstract":"This paper proposes a new method, called PLSR (partial least-squares regression), which is used for assessing harmonic impedance and the harmonic emission level at the point of common coupling (PCC). Utilizing the signals of harmonic voltage and harmonic current measured synchronously at PCC, regression coefficients are worked out through partial least-squares algorithm. By separating and filtering the measured data, the comprehensive variables that can explain dependent variables most effectively are distilled, and then the useful information and noise are identified from the measured data. Therefore, the disadvantage of variable dependence in establishing of the system model is overcome. After that, the supply harmonic impedance is got, consequently the harmonic emission level of customer is calculated. The simulation analysis and the analytic result of practical engineering road-testing data indicate that the proposed method is valid and feasible.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"78 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121820896","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}
{"title":"A Wavelet Transform Method for Characterization of Voltage Variations","authors":"H.Y. Zhu, S. Chen","doi":"10.1109/ICPST.2006.321959","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321959","url":null,"abstract":"Short duration voltage variation is one of the most commonly encountered power quality disturbances. The severity is generally determined by the remaining voltage RMS magnitude and the duration of the disturbance. These are generally determined through the RMS measurement method, which at times faces difficulties especially with variations of very short duration. This paper proposes an alternative technique to effectively characterize voltage variations of all durations. It uses wavelet analysis to zoom into a high frequency band for the time information, and the fundamental frequency band for the magnitude change. It is shown to be effective even for very short interruption, which is difficult to determine using the RMS method. Compared to other wavelet methods, its low computational requirement makes it suitable for real-time application. Dynamic simulations were used to demonstrate the capability of this method.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123805054","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}
{"title":"A novel nucleolus allocation of fixed transmission cost for various transaction modes","authors":"X. Gao, J. Peng, A. Luo","doi":"10.1109/ICPST.2006.321501","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321501","url":null,"abstract":"A novel nucleolus allocation of fixed transmission cost for various transaction modes is presented in this paper. It is based on newly proposed definition and method of the equivalent transformation of bilateral transactions into pool ones. A nucleolus model for allocating fixed transmission cost is established after all bilateral transactions changed into pool ones. The nucleolus resolution is then taken as the allocation results of the fixed transmission cost to both pool and equivalent pool transactions according to cooperative game and economic theories. In turn, the load and generator(s) involved in a transaction will further share half of the fixed transmission cost allocated to the transaction, respectively. Each generator will share the fixed transmission cost in proportion to their contribution to the load of the transaction. Simulation results of IEEE 14-bus system show that the proposed method is effective.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"256 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114296492","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}
Youzhong Miao, Tao Wu, Jiayang Guo, Qunju Li, Weimin Su, Yong Tang
{"title":"Mechanism Study of Large Power Oscillation of Inter-area Lines Caused by Local Mode","authors":"Youzhong Miao, Tao Wu, Jiayang Guo, Qunju Li, Weimin Su, Yong Tang","doi":"10.1109/ICPST.2006.321872","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321872","url":null,"abstract":"Based on eigenvalue analysis of small signal stability analysis, mechanism of large power oscillations of inter-area lines caused by local mode is studied by right eigenvector characteristic and generator power-angle characteristic. Eigenvalue of local mode is changing with running conditions and relations between the elements of right eigenvector of all generators also are changed. When power deviations' sum of all generator units located in one area caused by local mode oscillation is very large value, large power oscillations in inter-area lines will emerge, and the synthetic direction of power deviations of the generators in other area is similar to the strong participation generator of local mode, is contrary to the generators located in the same area with the local mode generator. A field data case of West Inner Mongolia power grid oscillation has proved the oscillation mechanism being, and corresponding analytic method and improved measures are proposed.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125116092","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}
{"title":"Research on Integration of Transformer Protection and On-line Detecting Winding Deformation Based on Equivalent Circuit Equation","authors":"Hao Zhi-guo, Zhang Bao-hui, Li Peng, Chu Yun-long","doi":"10.1109/ICPST.2006.321615","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321615","url":null,"abstract":"This paper bring forward new algorithms that integrate on-line detecting winding deformation into transformer, which is based on Equivalent Circuit Equation (ECE) of transformer. Firstly, the protection algorithm based on ECE is presented, and the criterion functions are derived for single-phase and three-phase transformer. The leakage inductance is the key parameter in ECE, which is not available and changes follow winding deformation, the least square is adopted to service as parameter identification. The mathematical models for identification are derived. The dynamic simulation experiment data indicates that on-line identification of transformer winding leakage inductance parameter is not only precise but can effectively detect winding deformation. The protection algorithm is theoretically clear and it can correctly and rapidly recognize the various transformer internal short circuits with distinct features.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"158 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122420674","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}
{"title":"Optimal Measurement Placement for Power System State Estimation Using Hybrid Genetic Algorithm and Simulated Annealing","authors":"T. Kerdchuen, W. Ongsakul","doi":"10.1109/ICPST.2006.321730","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321730","url":null,"abstract":"This paper proposes a hybrid genetic algorithm and simulated annealing (GA/SA) for solving optimal measurement placement for power system state estimation. Even though the global minimum measurement pair number is (N- 1) , their positions are required to make the system observable. GA/SA algorithm is based on genetic algorithm (GA) process. The acceptance criterion of simulated annealing (SA) is used for chromosome selection. Single measurement pair loss contingency is also considered. The Pthetas observable concept is used to check the network observability. Test results of 10-bus, IEEE 14, 30, 57 and 118-bus systems indicate that GA/SA is superior to tabu search (TS), GA and SA in terms of higher frequency of the best hit and faster computational time.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131406489","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}
Yin Yonghua, Zhang Jinping, Z. Hui, Song Dunwen, Xiong Min
{"title":"Development of Transformer Neutrals DC Current Blocking Device in High Power System","authors":"Yin Yonghua, Zhang Jinping, Z. Hui, Song Dunwen, Xiong Min","doi":"10.1109/ICPST.2006.321506","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321506","url":null,"abstract":"The DC current through transformer neutrals was harmful for transformer operation and influenced system stability. Among several methods of limiting or eliminating neutrals DC current, series capacitor method, composed by capacitor and fault bypass system, was an ideal way. Several criterions must be followed, they were: no or less influence to relevant relays and automations; tolerance worst fault current and keep safety of transformers and neutrals; in normal system mode must ensure neutrals in capacitor ground state; once neutrals voltage overpass threshold, bypass system should be put into operation in limited time; economical and feasible for installation, testing & maintenance, etc. Capacitor had been adopted as main component, which had been inserted between transformer neutrals and earth. Bypass system had paralleled with capacitor and composed of a full- wave diode bridge rectifier, thyristor trigger circuit, pre-test circuit before capacitor-ground, fast breaker and other auxiliary components. When transformer neutrals in direct-ground state, and DC current through transformer neutrals over setting up value, a pre -trigger process of thyristor started to check whether bypass system run correctly, if right, device transferred neutral grounding state from direct-ground to capacitor-ground; when in capacitor-ground state, if system fault event occurred and terminal voltage surpassed threshold, trigger circuit had been fired to make neutrals to direct ground state as quickly as 20 us and simultaneously fast breaker operated and ensured metal ground below 25 ms. Built in control unit and recorder unit improved device automation and reliability .By remote terminal several devices could be monitored. For engineering required, the prototype model device had been produced. Factory test including big current surge endurance and automation characteristic showed this device could satisfy power system field application.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131493416","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}
{"title":"Design and Reliability Analysis of High Power DC Thyristor Breaker","authors":"J. Wen, P. Fu, G. Tang, Z.Z. Liu","doi":"10.1109/ICPST.2006.321810","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321810","url":null,"abstract":"As a new type of circuit interrupter, DC thyristor breaker is very suit for high power DC system, such as subway, poloidal field power supply system of TOKAMAK (nuclear fusion experiment device), in which the transfer principle and force commutation technology was applied. In this paper, firstly, design of high power DC thyristor breaker has been finished, including main circuit design, snubber circuit design, commutation circuit optimize design, charger circuit design. Secondly, the reliability analysis of high power DC thyristor breaker has been presented, such as turn-off reliability analysis, turn-on reliability analysis, on-state and off-state reliability analysis. In these design and reliability analysis, some important conclusion have been derived, especially such as optimize design formulation of commutation circuit, the influences of distribution resistance in commutated circuit, the influence of stray inductance and their dispersivity in parallel connection thyristor branches for turn-off reliability, the influences of snubber circuit design for turn-on reliability, on- state and off-state reliability and so on. At last, we finished development and experiment of a bi-directional DC thyristor breaker for the poloidal field power supply system in EAST Super-conductive TOKAMAK Experiment result validated the correctness of the work above.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131527555","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}
{"title":"Tracing the Flow for Transmission System Based on Components","authors":"Wei Li, H. Bao, Bo Li","doi":"10.1109/ICPST.2006.321507","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321507","url":null,"abstract":"In this paper a method, which is called injection power components theory, for tracing power flow and loss allocation is brought forward. By means of dividing the injection power of sources into components including self-power and mutual-power components and analyzing components' distribution on meshed network, the characteristics of power distribution is given. Firstly, based on the basic circuit theory without assumptions, analytic expression of power injection of a source is put forward. Then power injection of a particular source is decomposed into power components which number is equal to the square of the number of total sources in meshed network. At last the mathematical process is given to prove that any a component meets the power conservation law, and any a power component is independently distributed based on the different rules and complies with the law of power components conservation. In order to demonstrate the applications of the proposed method, IEEE 9-bus system are used to allocate to participants. Result studies show that the proposed method is simple, reasonable and practical.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127699008","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}
{"title":"Predictive Optimal algorithm based Coordinated voltage Control for large power system","authors":"P. Ye, Qing Bian, Jiahua Song, B. Yao","doi":"10.1109/ICPST.2006.321671","DOIUrl":"https://doi.org/10.1109/ICPST.2006.321671","url":null,"abstract":"Misbalance between reactive power production and consumption in power system causes the variation of node voltage outside the proposed limit. It is a main task for system operators to maintain the voltage profile against any unexpected disturbance. In this paper a simple and practical coordinated secondary voltage control (CSVC) method was present, which was based on the predictive optimal algorithm. By taking the changing tendency of reactive power into consideration, a discrete predictive optimal control scheme was proposed, additional measurements were used in order to offset the effects of the loads variation and the changing of reactive power among neighboring areas. Grey model (GM) was employed to predict the changing tendency of reactive power in the tie lines and in the main loads node. Then based on the prediction results an optimal calculation was used to get the control law in each control step with the consideration of reactive power changing tendency. The simulation results as examples on the large power system were presented to illustrate the validity of the improved control scheme.","PeriodicalId":181574,"journal":{"name":"2006 International Conference on Power System Technology","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132820240","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}