Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398657
A. Bonfiglio, M. Brignone, F. Delfino, M. Invernizzi, F. Pampararo, R. Procopio
The strong and intense increase of the number of Photovoltaic production plants has slowly changed the asset and the operation conditions of the electric system. The aim of the present work is to introduce an innovative optimized control strategy to exploit the reactive power resource generated by photovoltaic plants in order to improve the quality and efficiency of the low/medium voltage distribution network. Here, a methodology to define the optimal reactive power reference for every photovoltaic unit of the network is presented in order to pursue a well-defined goal, such as the minimization of the Joule losses or the voltage support. Such reference signals are then provided to the photovoltaic control systems that will guarantee the decoupling between the reactive power channel and the active power one, thanks to the use of the FeedBack Linearization (FBL) control technique. The problem is here formulated in a general way, therefore it can be extended to any possible grid configuration and test case scenario.
{"title":"A technique for the optimal control and operation of grid-connected photovoltaic production units","authors":"A. Bonfiglio, M. Brignone, F. Delfino, M. Invernizzi, F. Pampararo, R. Procopio","doi":"10.1109/UPEC.2012.6398657","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398657","url":null,"abstract":"The strong and intense increase of the number of Photovoltaic production plants has slowly changed the asset and the operation conditions of the electric system. The aim of the present work is to introduce an innovative optimized control strategy to exploit the reactive power resource generated by photovoltaic plants in order to improve the quality and efficiency of the low/medium voltage distribution network. Here, a methodology to define the optimal reactive power reference for every photovoltaic unit of the network is presented in order to pursue a well-defined goal, such as the minimization of the Joule losses or the voltage support. Such reference signals are then provided to the photovoltaic control systems that will guarantee the decoupling between the reactive power channel and the active power one, thanks to the use of the FeedBack Linearization (FBL) control technique. The problem is here formulated in a general way, therefore it can be extended to any possible grid configuration and test case scenario.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127407849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398654
F. Parillo
In this paper are described a PI controller and an Active Filtering control strategy, applied to a Dual Boost Power Factor Correction (PFC) implementation, on a low cost FPGA device, using a custom developed sfloat24 math library. The implemented control strategy consists in an optimized power sharing where the active filtering approach is used to increase the current quality and at the same time to reduce the switching losses. The simulation results show that the sfloat24 floating point, IEEE 754 compliant, digital PI controller and the active filtering approach outperform by high-speed response, better precision, minor error and high dynamic range. Both the simulation and experimental results show that the adopted control strategy for PFC achieves near unity power factor and a not negligible switching losses reduction.
{"title":"Dual boost high performances Power Factor Correction (PFC) control strategy implemented on a low cost FPGA device, using a custom sfloat24 developed math library","authors":"F. Parillo","doi":"10.1109/UPEC.2012.6398654","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398654","url":null,"abstract":"In this paper are described a PI controller and an Active Filtering control strategy, applied to a Dual Boost Power Factor Correction (PFC) implementation, on a low cost FPGA device, using a custom developed sfloat24 math library. The implemented control strategy consists in an optimized power sharing where the active filtering approach is used to increase the current quality and at the same time to reduce the switching losses. The simulation results show that the sfloat24 floating point, IEEE 754 compliant, digital PI controller and the active filtering approach outperform by high-speed response, better precision, minor error and high dynamic range. Both the simulation and experimental results show that the adopted control strategy for PFC achieves near unity power factor and a not negligible switching losses reduction.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128986375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398429
L. Wu, D. Infield
As wind power penetration into power systems increases, it poses a growing challenge to power system operation and stability. This is partly because wind power is highly time variable and cannot inherently contribute to power system frequency regulation. The provision of frequency support from wind turbines under changing wind conditions is examined in this paper. A simplified variable speed wind turbine model is developed. A modified turbine controller to deliver inertial and droop response is proposed. The interaction between inertial and droop response from wind turbines is examined under varying wind.
{"title":"Investigation on the interaction between inertial response and droop control from variable speed wind turbines under changing wind conditions","authors":"L. Wu, D. Infield","doi":"10.1109/UPEC.2012.6398429","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398429","url":null,"abstract":"As wind power penetration into power systems increases, it poses a growing challenge to power system operation and stability. This is partly because wind power is highly time variable and cannot inherently contribute to power system frequency regulation. The provision of frequency support from wind turbines under changing wind conditions is examined in this paper. A simplified variable speed wind turbine model is developed. A modified turbine controller to deliver inertial and droop response is proposed. The interaction between inertial and droop response from wind turbines is examined under varying wind.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127361091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398688
Z. Benhachani, B. Azoui, R. Abdessemed, M. Chabane
In this paper, we study the sizing and economic optimization of a stand-alone photovoltaic-wind hybrid system with storage batteries, installed in a semi arid region of Algeria supplying a farm. Two methods are developed. The first method is based on the average annual monthly values in which the size of photovoltaic (PV) and wind generators is determined from the average monthly contribution of each component. In the second method, the determination of the size of these two components of the system is based on the worst month. The data comes from the local meteorological station. The consumption profile which has been adopted corresponds to the profile typically found in isolated sites. The optimization was performed taking into account the economic parameter to find the technical and economic optimum configuration. The results show that the studied site is well adapted for solar and wind applications. The sunshine duration is over 2000 hours annually. The energy acquired daily on a horizontal surface can exceed 7kWh/m2 in the summer period and it is annually in the order of 1780 kWh/m2 for a horizontal plane and can exceed 2000 kWh/m2 for an optimal tilt. The average annual wind speed at a 10m height is 3.61m/s and the monthly average speed is over 4m/s in the period of March, April and May. Our study shows that the main benefit of introducing a wind system with a solar one is in the total cost reduction especially in the size of the PV array and battery.
{"title":"Optimal sizing of a solar-wind hybrid system supplying a farm in a semi-arid region of Algeria","authors":"Z. Benhachani, B. Azoui, R. Abdessemed, M. Chabane","doi":"10.1109/UPEC.2012.6398688","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398688","url":null,"abstract":"In this paper, we study the sizing and economic optimization of a stand-alone photovoltaic-wind hybrid system with storage batteries, installed in a semi arid region of Algeria supplying a farm. Two methods are developed. The first method is based on the average annual monthly values in which the size of photovoltaic (PV) and wind generators is determined from the average monthly contribution of each component. In the second method, the determination of the size of these two components of the system is based on the worst month. The data comes from the local meteorological station. The consumption profile which has been adopted corresponds to the profile typically found in isolated sites. The optimization was performed taking into account the economic parameter to find the technical and economic optimum configuration. The results show that the studied site is well adapted for solar and wind applications. The sunshine duration is over 2000 hours annually. The energy acquired daily on a horizontal surface can exceed 7kWh/m2 in the summer period and it is annually in the order of 1780 kWh/m2 for a horizontal plane and can exceed 2000 kWh/m2 for an optimal tilt. The average annual wind speed at a 10m height is 3.61m/s and the monthly average speed is over 4m/s in the period of March, April and May. Our study shows that the main benefit of introducing a wind system with a solar one is in the total cost reduction especially in the size of the PV array and battery.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"29 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134010267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398607
J. Bekker, H. Vermeulen
The installed capacity of wind generation systems has increased dramatically in recent years, thereby increasing the need for efficient model implementations for operational applications such as simulating system behaviour and grid interactions, identifying and quantifying ageing effects and performing condition monitoring. While the model topologies for conventional systems are well established, the methodologies for determining parameter values from online measurements require further research, especially for applications such as condition monitoring. This paper presents the results of an exploratory investigation to estimate the model parameters of a double-fed induction generator used in a classical wind generation system that includes a wind turbine blade, gearbox and simplified grid model. The investigation is conducted using dedicated Matlab implementations of C-code S-function models of the various system components, compiled as a Simulink library. This approach ensures highly efficient model implementations with fast simulation times as is typically required by parameter estimation processes. Results are presented for case studies performed on both ABC and DQ generator model implementations, with the generator either operated in isolation or as part of a wind generation system. The investigation considers two perturbation signals, namely step perturbations applied to the rotor angular velocity and stator voltages respectively. The results show that the electrical parameters of the generator can be estimated with good accuracy using these model implementations, operating topologies and perturbation signals.
{"title":"Parameter estimation of a doubly-fed induction generator in a wind generation topology","authors":"J. Bekker, H. Vermeulen","doi":"10.1109/UPEC.2012.6398607","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398607","url":null,"abstract":"The installed capacity of wind generation systems has increased dramatically in recent years, thereby increasing the need for efficient model implementations for operational applications such as simulating system behaviour and grid interactions, identifying and quantifying ageing effects and performing condition monitoring. While the model topologies for conventional systems are well established, the methodologies for determining parameter values from online measurements require further research, especially for applications such as condition monitoring. This paper presents the results of an exploratory investigation to estimate the model parameters of a double-fed induction generator used in a classical wind generation system that includes a wind turbine blade, gearbox and simplified grid model. The investigation is conducted using dedicated Matlab implementations of C-code S-function models of the various system components, compiled as a Simulink library. This approach ensures highly efficient model implementations with fast simulation times as is typically required by parameter estimation processes. Results are presented for case studies performed on both ABC and DQ generator model implementations, with the generator either operated in isolation or as part of a wind generation system. The investigation considers two perturbation signals, namely step perturbations applied to the rotor angular velocity and stator voltages respectively. The results show that the electrical parameters of the generator can be estimated with good accuracy using these model implementations, operating topologies and perturbation signals.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130507325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398587
F. Olobaniyi, Hassan NOURI, S. Ghauri
The resourcefulness of Diakoptics as a tool with the potential ability to meet the challenges of modern power system analysis is outlined. The benefits include the generally accepted saving in computation time, but higher accuracy and the ability to use multicomputer configurations in analyses are highlighted. One of the reasons for the non-acceptance of Diakoptics as a universal tool is said to be the difficulty in understanding the concept. The concept is demonstrated using simple illustrative examples that are easy to understand and verify.
{"title":"Investigation of Diakoptics as a resourceful tool in power system analysis","authors":"F. Olobaniyi, Hassan NOURI, S. Ghauri","doi":"10.1109/UPEC.2012.6398587","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398587","url":null,"abstract":"The resourcefulness of Diakoptics as a tool with the potential ability to meet the challenges of modern power system analysis is outlined. The benefits include the generally accepted saving in computation time, but higher accuracy and the ability to use multicomputer configurations in analyses are highlighted. One of the reasons for the non-acceptance of Diakoptics as a universal tool is said to be the difficulty in understanding the concept. The concept is demonstrated using simple illustrative examples that are easy to understand and verify.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130507950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398645
L. Shpanin, G. Jones, N. Shammas, J. Humphries, S. Tennakoon, J. W. Spencer
This paper describes a novel technique for interrupting direct currents (D.C.) with an electromagnetically convoluted arc in air at atmospheric pressure. Investigations are reported on the effects of using a separate current for producing the arc convolving electromagnetic field (B-field) to that being interrupted and using a separate R, L, C circuit in parallel with the arc contacts. Experimental results are presented for the time variation of currents flowing through the arc gap, the B-field coil and the parallel R, L, C circuit, along with the voltage across the arc gap.
{"title":"Electromagnetically convoluted arcs for the interruption of quasi direct current","authors":"L. Shpanin, G. Jones, N. Shammas, J. Humphries, S. Tennakoon, J. W. Spencer","doi":"10.1109/UPEC.2012.6398645","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398645","url":null,"abstract":"This paper describes a novel technique for interrupting direct currents (D.C.) with an electromagnetically convoluted arc in air at atmospheric pressure. Investigations are reported on the effects of using a separate current for producing the arc convolving electromagnetic field (B-field) to that being interrupted and using a separate R, L, C circuit in parallel with the arc contacts. Experimental results are presented for the time variation of currents flowing through the arc gap, the B-field coil and the parallel R, L, C circuit, along with the voltage across the arc gap.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"227 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134481995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398421
P. Mikropoulos, V. Zagkanas, T. S. Koustoulidis
Knowledge on the effects of air density on corona discharge is of great importance for many practical applications, including overhead transmission lines. In the present study the salient characteristics of both positive and negative DC corona on 7-stranded conductors, namely the corona inception voltage, corona current and the associated power losses, are experimentally investigated in the coaxial cylindrical electrode arrangement under variable air density. Theoretical predictions of the corona current and losses are in good agreement with experimental values for an ion mobility decreasing with relative air density according to a power law, the rate of decrease being higher for negative than positive ions. Irregularity factors for the 7-stranded conductors have been obtained based on electric field simulations and Peek's formula for smooth conductors. Logarithmic expressions, describing well the dependence of the irregularity factor on the product of relative air density and conductor radius, allow for a satisfactory estimation of the corona inception field strength of 7-stranded conductors.
{"title":"Experimental investigation of DC corona on stranded conductors under variable air density","authors":"P. Mikropoulos, V. Zagkanas, T. S. Koustoulidis","doi":"10.1109/UPEC.2012.6398421","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398421","url":null,"abstract":"Knowledge on the effects of air density on corona discharge is of great importance for many practical applications, including overhead transmission lines. In the present study the salient characteristics of both positive and negative DC corona on 7-stranded conductors, namely the corona inception voltage, corona current and the associated power losses, are experimentally investigated in the coaxial cylindrical electrode arrangement under variable air density. Theoretical predictions of the corona current and losses are in good agreement with experimental values for an ion mobility decreasing with relative air density according to a power law, the rate of decrease being higher for negative than positive ions. Irregularity factors for the 7-stranded conductors have been obtained based on electric field simulations and Peek's formula for smooth conductors. Logarithmic expressions, describing well the dependence of the irregularity factor on the product of relative air density and conductor radius, allow for a satisfactory estimation of the corona inception field strength of 7-stranded conductors.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133498322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398428
R. J. de Groot, J. Morren, J. Slootweg
Implementation of distribution automation into medium and low voltage grids is gaining more and more support amongst distribution grid operators. In order to assess the feasibility and usefulness of dynamic network reconfiguration for the purpose of reducing losses and increasing available network capacity, it is necessary to know to what extent simultaneity amongst MV/LV transformers within distribution networks occurs. Measurements have been done in parts of the distribution network of Enexis, one of the largest distribution network operators in the Netherlands. For a full year, in 30 MV/LV substations the transformer and all outgoing low voltage feeders have been measured. In this paper the measurement data is being analyzed in order to determine the degree of simultaneity in low voltage distribution grids, both seen from the low- and the medium-voltage level. The results of this analysis will be used to assess the feasibility of power flow optimization by using distribution automation. Furthermore, an example of a field application will be simulated and discussed.
{"title":"Investigation of simultaneity in distribution networks for the assessment of DA feasibility","authors":"R. J. de Groot, J. Morren, J. Slootweg","doi":"10.1109/UPEC.2012.6398428","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398428","url":null,"abstract":"Implementation of distribution automation into medium and low voltage grids is gaining more and more support amongst distribution grid operators. In order to assess the feasibility and usefulness of dynamic network reconfiguration for the purpose of reducing losses and increasing available network capacity, it is necessary to know to what extent simultaneity amongst MV/LV transformers within distribution networks occurs. Measurements have been done in parts of the distribution network of Enexis, one of the largest distribution network operators in the Netherlands. For a full year, in 30 MV/LV substations the transformer and all outgoing low voltage feeders have been measured. In this paper the measurement data is being analyzed in order to determine the degree of simultaneity in low voltage distribution grids, both seen from the low- and the medium-voltage level. The results of this analysis will be used to assess the feasibility of power flow optimization by using distribution automation. Furthermore, an example of a field application will be simulated and discussed.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122962120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1109/UPEC.2012.6398552
Yongzheng Mu, Zongxiang Lu, Ying Qiao, K. Lo
To increase the stability and efficiency of the Grid with wind power integration, one of the solutions is to control the active power output of wind farms. This paper focuses on wind farms with DFIG wind turbines, and analyzes the stability of DFIGs working in different control strategies. An optimized control strategy is proposed that guides the active power output of a DFIG wind farm to follow the reference power curve. By controlling the rotating speed of the DFIGs in a wind farm, the control strategy minimizes the amount of energy loss during its operation. Simulation results show that the control strategy can effectively follow the reference power curve and keep the DFIGs stable.
{"title":"Optimized active power control of DFIG wind farm","authors":"Yongzheng Mu, Zongxiang Lu, Ying Qiao, K. Lo","doi":"10.1109/UPEC.2012.6398552","DOIUrl":"https://doi.org/10.1109/UPEC.2012.6398552","url":null,"abstract":"To increase the stability and efficiency of the Grid with wind power integration, one of the solutions is to control the active power output of wind farms. This paper focuses on wind farms with DFIG wind turbines, and analyzes the stability of DFIGs working in different control strategies. An optimized control strategy is proposed that guides the active power output of a DFIG wind farm to follow the reference power curve. By controlling the rotating speed of the DFIGs in a wind farm, the control strategy minimizes the amount of energy loss during its operation. Simulation results show that the control strategy can effectively follow the reference power curve and keep the DFIGs stable.","PeriodicalId":326950,"journal":{"name":"2012 47th International Universities Power Engineering Conference (UPEC)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128406082","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：