A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit....A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit.With the application of two-stage three-phase continuous power supply structure,the electrical characteristics exhibit new features differing from the existing traction system.In this work,the principle for voltage levels determining two-stage network is dissected in accordance with the requirements of traction network and electric locomotive.The equivalent model of three-phase traction system is built for deducing the formula of current distribution and voltage losses.Based on the chain network model of the traction network,a simulation model is established to analyze the electrical characteristics such as traction current distribution,voltage losses,system equivalent impedance,voltage distribution,voltage unbalance and regenerative energy utilization.In a few words,quite a lot traction current of about 99%is undertaken by long-section cable network.The proportion of system voltage losses is small attributed to the two-stage three-phase power supply structure,and the voltage unbal-ance caused by impedance asymmetry of traction network is less than 1‰.In addition,the utilization rate of regenerative energy for locomotive achieves a significant promotion of over 97%.展开更多
The Asia Pacific Economic Cooperation(APEC)comprises of the world’s largest producers and consumers of energy,accounting for 60.3%of primary energy supply,50.0%of final energy consumption,and 63.0%of electricity gene...The Asia Pacific Economic Cooperation(APEC)comprises of the world’s largest producers and consumers of energy,accounting for 60.3%of primary energy supply,50.0%of final energy consumption,and 63.0%of electricity generation worldwide in 2016.This study discusses the primary energy supply and final energy consumption situation of the APEC and analyzes the characteristics of electricity in terms of its generation structure based on fuel,consumption by the end-use sector,access to electricity,and so on.The renewable energy and electricity generation projections up to 2030 based on trends in the APEC are also assessed.It is seen that electricity in final energy consumption has been on an upward trend,with an average annual growth rate of about 4.8%during 2006–2016,in 2016,its share reached 24.3%.The industry sector consumes the largest share of electricity,accounting for about 45.5%in 2016.Coal supply and consumption peaked in 2011 and then began to decline,while renewable energy has been on an upward trend,with its primary energy supply share increasing from 4.80%in 2010 to 6.29%in 2016.Solar photovoltaic and onshore wind power are on the verge of costing less than the operating cost of existing coal-fired plants in 2018.In the APEC’s target scenario in which renewable energy is doubled,the predicted net growth from 2017 to 2030 of solar,wind,and hydro power is about 963,497,and 157 GW,respectively,and to reach this target,the APEC economies need to accelerate renewable energy development.展开更多
National development requires adequate electricity supply of which all activities--generation, transmission and distribution leading to it are capital-intensive in terms of funds, natural and human resources. The dwin...National development requires adequate electricity supply of which all activities--generation, transmission and distribution leading to it are capital-intensive in terms of funds, natural and human resources. The dwindling power sector government funding coupled with low private sector participation and weak level political will require creative and innovative solutions in addressing the power supply problem in Nigeria. Hence, this paper seeks to examine power sector privatization as a viable option.展开更多
This research aims to study the sustainability of Taiwan power supplychain based on system dynamics forecasting. The paper tries to investigate electricity shortage effects not only on the industrial side, but also f...This research aims to study the sustainability of Taiwan power supplychain based on system dynamics forecasting. The paper tries to investigate electricity shortage effects not only on the industrial side, but also from the standpointof society. In our model, different forecasting methods such as linear regression,time series analysis, and gray forecasting are also considered to predict the parameters. Further tests such as the structure, dimension, historical fit, and sensitivityof the model are also conducted in this paper. Through analysis forecasting result,we believe that the demand for electricity in Taiwan will continue to increase to acertain level for a period of time in the future. This phenomenon is closely relatedto Taiwan’s economic development, especially industrial development. We alsopoint out that electricity prices in Taiwan do not match with high industrialdemand, and that prices are still slightly low. Finally, the future growth trend ofTaiwan’s electricity demand has not changed, and ensuring adequate supply tomeet electricity demand to prevent potential power shortages will pose somedifficulty.展开更多
基金This research was supported by the Science and Technology Plan Project of Sichuan Province(No.21YYJC3324)the Science and Technology Plan Project of Sichuan Province(No.2022YFQ0104).
文摘A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit.With the application of two-stage three-phase continuous power supply structure,the electrical characteristics exhibit new features differing from the existing traction system.In this work,the principle for voltage levels determining two-stage network is dissected in accordance with the requirements of traction network and electric locomotive.The equivalent model of three-phase traction system is built for deducing the formula of current distribution and voltage losses.Based on the chain network model of the traction network,a simulation model is established to analyze the electrical characteristics such as traction current distribution,voltage losses,system equivalent impedance,voltage distribution,voltage unbalance and regenerative energy utilization.In a few words,quite a lot traction current of about 99%is undertaken by long-section cable network.The proportion of system voltage losses is small attributed to the two-stage three-phase power supply structure,and the voltage unbal-ance caused by impedance asymmetry of traction network is less than 1‰.In addition,the utilization rate of regenerative energy for locomotive achieves a significant promotion of over 97%.
基金sponsored by the National Key Research and Development Program of China (Grant No. 2018YFC0704400)the Programmer of Introducing Talents (Grant No. B13011)
文摘The Asia Pacific Economic Cooperation(APEC)comprises of the world’s largest producers and consumers of energy,accounting for 60.3%of primary energy supply,50.0%of final energy consumption,and 63.0%of electricity generation worldwide in 2016.This study discusses the primary energy supply and final energy consumption situation of the APEC and analyzes the characteristics of electricity in terms of its generation structure based on fuel,consumption by the end-use sector,access to electricity,and so on.The renewable energy and electricity generation projections up to 2030 based on trends in the APEC are also assessed.It is seen that electricity in final energy consumption has been on an upward trend,with an average annual growth rate of about 4.8%during 2006–2016,in 2016,its share reached 24.3%.The industry sector consumes the largest share of electricity,accounting for about 45.5%in 2016.Coal supply and consumption peaked in 2011 and then began to decline,while renewable energy has been on an upward trend,with its primary energy supply share increasing from 4.80%in 2010 to 6.29%in 2016.Solar photovoltaic and onshore wind power are on the verge of costing less than the operating cost of existing coal-fired plants in 2018.In the APEC’s target scenario in which renewable energy is doubled,the predicted net growth from 2017 to 2030 of solar,wind,and hydro power is about 963,497,and 157 GW,respectively,and to reach this target,the APEC economies need to accelerate renewable energy development.
文摘National development requires adequate electricity supply of which all activities--generation, transmission and distribution leading to it are capital-intensive in terms of funds, natural and human resources. The dwindling power sector government funding coupled with low private sector participation and weak level political will require creative and innovative solutions in addressing the power supply problem in Nigeria. Hence, this paper seeks to examine power sector privatization as a viable option.
文摘This research aims to study the sustainability of Taiwan power supplychain based on system dynamics forecasting. The paper tries to investigate electricity shortage effects not only on the industrial side, but also from the standpointof society. In our model, different forecasting methods such as linear regression,time series analysis, and gray forecasting are also considered to predict the parameters. Further tests such as the structure, dimension, historical fit, and sensitivityof the model are also conducted in this paper. Through analysis forecasting result,we believe that the demand for electricity in Taiwan will continue to increase to acertain level for a period of time in the future. This phenomenon is closely relatedto Taiwan’s economic development, especially industrial development. We alsopoint out that electricity prices in Taiwan do not match with high industrialdemand, and that prices are still slightly low. Finally, the future growth trend ofTaiwan’s electricity demand has not changed, and ensuring adequate supply tomeet electricity demand to prevent potential power shortages will pose somedifficulty.
