2008 12th International Middle-East Power System Conference最新文献

{"title":"Magnetizing inductance identification algorithm for operation of speed-sensorless induction motor drives in the field weakening region","authors":"M. Zaky, M. Khater, H. Yasin, S. Shokralla","doi":"10.1109/MEPCON.2008.4562372","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562372","url":null,"abstract":"Accurate speed estimation of sensorless induction motor drives in the field weakening region depends on the precise magnetizing inductance which varies due to rotor flux reference variation and consequently, the main flux saturation. Therefore, the structure of the speed observer should be modified in such a way that the variation of main flux saturation is recognized within the speed estimation algorithm. In this paper, the sliding mode observer (SMO) of a sensorless induction motor drive is modified for a wide speed range operation at speeds higher than the base speed. The online identification algorithm of magnetizing inductance to operate in the field weakening region is presented. The identification algorithm is based on measured stator voltages and currents and the magnetizing curve of the machine. Simulation and experimental results are presented on indirect field oriented controller of an induction motor drive with compensation of main flux saturation to demonstrate the effectiveness of the modified SMO to operate in the field weakening region.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116488699","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 simplified dynamic simulation model (prototype) for a stand-alone Polymer Electrolyte Membrane (PEM) fuel cell stack","authors":"D. Ali","doi":"10.1109/MEPCON.2008.4562321","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562321","url":null,"abstract":"The ever increasing demand for electrical energy and the rise in the electricity prices due to the recent instability of the oil prices in addition to the degrading of the air quality resulting from the emissions of the existing energy conversion devices has intensified research into alternative renewable sources of electrical energy. In this paper a dynamic electrochemical model is developed to simulate a polymer electrolyte membrane fuel cell (PEMFC) system to allow the development and improvement of electrical energy generation systems using this new promising technology. Although other models have been produced but most of these capture the fuel cell (FC) steady state behaviour by estimating its voltage for a particular set of operating conditions. The proposed model allows the incorporation of effects of different dynamic conditions in load current, pressure of input reactant gases, fuel cell operating temperature as well as the mass/heat transfer transient features in the fuel cell body. Its capability of predicting transient dynamics will also prove useful when attempting to develop a control strategy. The proposed model strength is modularizing the fundamental thermal- physical behaviour of a fuel cell and developing a modular block that can be used as a part of any other schematic solution required for fuel cells' study. The developed modular block (prototype) exhibits most of the basic fuel cell properties and incorporates essential physical and electrochemical processes that happen along its operation, allowing its' easy moderation for modelling other fuel cells with different cell parameters and allow investigation of their behaviour for any operating or design configuration. The prototype can be useful in future in studying the integration of fuel cells into distribution power systems. The proposed modular block is implemented in SIMULINK and is verified by generating model results and comparing this to benchmark results for a Ballard NEXAtrade Power module. The proposed model was also compared to another simplified model; sample results for a Ballard V PEMFC were generated for both models indicating that the developed model is more accurate in simulating the fuel cell especially at high operating current densities.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124388390","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":"Nonlinear control scheme for VSC-HVDC transmission systems","authors":"M. Rashed, S.M.A. El-Anwar, F. Youssef","doi":"10.1109/MEPCON.2008.4562382","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562382","url":null,"abstract":"This paper presents a nonlinear control scheme for VSC-HVDC transmission system. The design of the proposed nonlinear controller has been performed in a rotating reference frame fixed to the grid voltage vectors. The controller is designed to provide high dynamic performance and complete decouple control of active and reactive power. Simulation of the proposed VSC-HVDC control scheme has been performed using Matlab/SimPowSys. Steady state and transient performance under various operating conditions have been examined. The results have been compared with that of a conventional PI control scheme. The nonlinear controller has provided excellent transient and steady state performance as well as complete decouple control of active and reactive power.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124486909","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":"Application of zero-reflection controllers on two-dimensional power systems","authors":"W. Sabry","doi":"10.1109/MEPCON.2008.4562330","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562330","url":null,"abstract":"This paper introduces the application of a zero-reflection controller (ZRC); designed for the two-dimensional large electric power systems. The controller is designed to oppose the effects of power system electromechanical wave propagation that follow disturbances occurring at any point in the mentioned power system. The continuum principle, which considered for the proposed power system leads to a set of nonlinear partial differential equations (PDE). So, the discretization concept was applied in this paper. Analysis of ZRC effects is performed for different system cases. MATLAB package is used to carry out the simulation. Simulation results in different situations are presented and discussed. These results present and show the important effects of ZRCs in two-dimensional power system electromechanical wave propagation mitigation.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127756884","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":"Study of nonlinear-carrier control stability for PFC boost converters","authors":"R. Haron, M. Orabi, M. El-Sadek, A. Elaroudi","doi":"10.1109/MEPCON.2008.4562300","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562300","url":null,"abstract":"Nonlinear control considers an elegant technique for boost PFC converters. Switch duty cycle is determined by comparing a signal derived from the main switch current with a periodic, nonlinear carrier waveform that forces the input current to follow the input line voltage. That results in a near unity power factor. However, nonlinear phenomena have been detected in PFC circuits resulted in low power factor. In this paper, a study of the stability of nonlinear control in pre-regulator PFC converter with resistive load and two-stage PFC converter where DC-DC has replaced the load. Both circuits have been tested to determine the practical limitation for stable and unstable regions. Lastly, some design guidelines have been made clear for stable operation using stability maps.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125685344","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":"Robust flux observer system with sliding mode field oriented control of induction motors","authors":"H. Shehadeh, H. Abu-Rub, S. Ahmed","doi":"10.1109/MEPCON.2008.4562399","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562399","url":null,"abstract":"This paper implements a new observer model in parallel with a sliding mode concept for a field oriented control drive system. The proposed system accounts for the problem of stator resistance variation. The use of feedback correction on the output of the observer eliminates the effect of stator resistance and makes the new observer robust in terms of motor parameter variation. A comparison between the outputs of a sliding mode based drive system and one without is presented. Simulation results using Matlab/Simulink are carried out.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127934776","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":"Performance analysis and realization of bipolar current waveforms for a Switched Reluctance Motor","authors":"M.A. Alkhazendar, F. Kader, Y.A. Hawwas, A. Kalas","doi":"10.1109/MEPCON.2008.4562395","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562395","url":null,"abstract":"This paper presents a detailed Performance analysis evaluation of a bipolar excitation for supplying a switched reluctance motor (SRM). The proposed method can significantly enhance the performance of the SRM in terms of efficiency and power quality. The bidirectional power converter is well justified by the extent of our improvement in performance of SRM drives, higher torque density, lower core losses. The results show that the THD in bipolar excitation is less than THD in unipolar the THD reduced by 26.77% Which introduce to improve power quality which obtained from the SRM under bipolar excitation technique.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132249854","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":"Adaptive variable structure series compensation for voltage stability improvement using internal recurrence neural network controller","authors":"A. Hemeida","doi":"10.1109/MEPCON.2008.4562324","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562324","url":null,"abstract":"The paper presents a control technique for variable structure series compensation (VSSrC) using internal recurrence adaptive neural network, IRANN controller for voltage stability enhancement in power systems. The present IRANN controller response is dependent on the power system response but independent on it's parameters. The IRANN implements a nonlinear adaptive functions which tracks the weights and bias matrices of the constructed internal recurrence neural network according to the power system response. The present controller implements speed deviation signal, Deltaomega and terminal voltage deviation signal DeltaVt added to feedback signals from the hidden layer as input signals. The output signal of the proposed controller is related to the power system response. The studied power system is modeled by a set of nonlinear algebraic and differential equations and solved by MATLAB software. The proposed scheme stabilize the studied system voltage in case of severe disturbance. A three phase short circuit fault at the main bus is considered for a period of 200 m.sec. To judge the present controller a comparative study is made with the conventional PI controller. The time response shows the superiority of the proposed IRANN controller over the PI controller in stabilizing the system voltage very fast.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133211960","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":"Long distance transmission line with controlled shunt reactors (CSRT)","authors":"G. Alexandrov, M. Dardeer","doi":"10.1109/MEPCON.2008.4562371","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562371","url":null,"abstract":"In this paper the power transmission line from hydro-power station at rapids of the river Congo to Egypt (4500 km) is considered. It is shown that the main problem of the electric energy transmission over long line is connected with a compensation of surplus reactive power of line. Three different variants for this line are presented in this paper with regulated shunt compensation in accordance with transmitted power over the line. For this purpose controlled shunt reactors of a transformer type (CSRT) are used. A mode of voltage by any transmitted power over the line is considered - from no load to natural mode of transmitted power.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115131961","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":"Operation evaluation of DWT-based earth fault detection in unearthed MV networks","authors":"N. Elkalashy, M. Lehtonen, H. A. Darwish, A. Taalab, M. Izzularab","doi":"10.1109/MEPCON.2008.4562385","DOIUrl":"https://doi.org/10.1109/MEPCON.2008.4562385","url":null,"abstract":"A novel selectivity technique to estimate the faulty feeder in MV networks was introduced in [1]. This technique depended on the directionality of discrete wavelet transform (DWT) detail coefficient of a residual current of each feeder with respect to the DWT detail coefficient of the residual voltage. The algorithm efficacy has been examined with high impedance arcing fault due to leaning trees. In this paper, the algorithm performance is tested with resistance earth faults over a wide range of the fault resistance values (1 mOmega to 100 kOmega) as well as concerning practical fault cases such as arcing faults. The fault cases occurring at different locations in an unearthed 20 kV network are simulated by ATP/EMTP. Test cases confirm the efficacy of the proposed technique.","PeriodicalId":236620,"journal":{"name":"2008 12th International Middle-East Power System Conference","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116492213","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}