The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the develo...The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the development and fabrication costs significantly.In this paper,the TOPSIS method along with the NSGA-Ⅱis employed to find an optimum family of EPS for an automotive platform.A multi-objective optimization problem is defined considering road feel,steering portability,RMS of Ackerman error,and product family penalty function(PFPF)as the conflicting objective functions.The results for the single objective optimization problems and the ones for the multi-objective optimization problem,as well as two suggested trade-off design points are presented,compared and discussed.For the two suggested points,performance at one objective function is deteriorated by about 1%,while the commonality is increased by 20%–40%,which shows the effectiveness of the proposed method in first finding the non-dominated design points and then selecting the trade-off among the obtained points.The results indicate that the obtained trade-off points have superior performance within the product family with maximum number of common parts.展开更多
A theoretical analysis of the electricity production of a photovoltaic solar power plant of 22 MW for different sites in Senegal is presented. The study is carried out in two coastal regions (Dakar and Saint-Louis) an...A theoretical analysis of the electricity production of a photovoltaic solar power plant of 22 MW for different sites in Senegal is presented. The study is carried out in two coastal regions (Dakar and Saint-Louis) and two continental regions (Mbacké and Linguère). This study is done using the RET Screen clean energy project management software climate data. The amount of electricity exported to the grid is calculated for each site. The results show that the climatic conditions of the coastal and continental regions are different from November to June. From July to October, which corresponds to the rainy season in Senegal, the climatic conditions of the coastal and continental regions are similar. The results also show that although the efficiency of photovoltaic modules is better on the coast, electricity production varies little from one site to another. Climate conditions in Senegal therefore have no impact on electricity production.展开更多
The low electricity supply rate is a major cause of underdevelopment in Cameroon. To address this issue, Cameroon outlined a strategy in 2003 aiming for a production capacity of 3000 MW by 2020. However, by 2020, prod...The low electricity supply rate is a major cause of underdevelopment in Cameroon. To address this issue, Cameroon outlined a strategy in 2003 aiming for a production capacity of 3000 MW by 2020. However, by 2020, production had only reached 1040 MW, leading Cameroon to devise a new national energy sector development strategy targeting 5000 MW by 2035. This paper provides an overview of the current state of energy production and projects future output by 2035. Scientific articles and investigative reports on energy production in Cameroon have enabled an assessment of the current electrical energy production. The 2035 production estimate is based on the Energy Sector Development Projects (PDSEN) report in Cameroon. The current production is estimated at around 1600 MW. Considering the ongoing construction of power plants, future projects, and financing delays, achieving the 5000 MW goal by 2035 appears challenging. Nonetheless, diversifying energy production sources could bring Cameroon closer to this target.展开更多
It is important to distribute the load efficiently to minimize the cost of the economic dispatch of electrical power system. The uncertainty and volatility of wind energy make the economic dispatch much more complex w...It is important to distribute the load efficiently to minimize the cost of the economic dispatch of electrical power system. The uncertainty and volatility of wind energy make the economic dispatch much more complex when the general power systems are combined with wind farms. The short term wind power prediction method was discussed in this paper. The method was based on the empirical mode decomposition (EMD) and ensemble empirical mode decomposition (EEMD). Furthermore,the effect of wind farms on the traditional economic dispatch of electrical power system was analyzed. The mathematical model of the economic dispatch was established considering the environmental factors and extra spinning reserve cost. The multi-objective co-evolutionary algorithm was used to figure out the model. And the results were compared with the NSGA-Ⅱ(non-dominated sorting genetic algorithm-Ⅱ) to verify its feasibility.展开更多
To address the challenges associated with existing separated zone oil production technologies,such as incompatibility with pump inspection operations,short effective working life,and poor communication reliability,an ...To address the challenges associated with existing separated zone oil production technologies,such as incompatibility with pump inspection operations,short effective working life,and poor communication reliability,an innovative electromagnetic coupling intelligent zonal oil production technology has been proposed.The core and accessory tools have been developed and applied in field tests.This technology employs a pipe string structure incorporation a release sub,which separates the production and allocation pipe strings.When the two strings are docked downhole,electromagnetic coupling enables close-range wireless transmission of electrical power and signals between the strings,powering multiple downhole intelligent production allocators(IPAs)and enabling two-way communication.Core tools adapted to the complex working conditions downhole were developed,including downhole electricity&signal transmission equipment based on electromagnetic coupling(EST),IPAs,and ground communication controllers(GCCs).Accessory tools,including large-diameter release sub anchor and cable-crossing packers,have also been technically finalized.Field tests conducted on ten wells in Daqing Oilfield demonstrated that the downhole docking of the two strings was convenient and reliable,and the EST worked stably.Real-time monitoring of flow rate,pressure and temperature in separate layers and regulation of zonal fluid production were also achieved.This technology has enhanced reservoir understanding and achieved practical production results of increased oil output with reduced water cut.展开更多
文摘The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the development and fabrication costs significantly.In this paper,the TOPSIS method along with the NSGA-Ⅱis employed to find an optimum family of EPS for an automotive platform.A multi-objective optimization problem is defined considering road feel,steering portability,RMS of Ackerman error,and product family penalty function(PFPF)as the conflicting objective functions.The results for the single objective optimization problems and the ones for the multi-objective optimization problem,as well as two suggested trade-off design points are presented,compared and discussed.For the two suggested points,performance at one objective function is deteriorated by about 1%,while the commonality is increased by 20%–40%,which shows the effectiveness of the proposed method in first finding the non-dominated design points and then selecting the trade-off among the obtained points.The results indicate that the obtained trade-off points have superior performance within the product family with maximum number of common parts.
文摘A theoretical analysis of the electricity production of a photovoltaic solar power plant of 22 MW for different sites in Senegal is presented. The study is carried out in two coastal regions (Dakar and Saint-Louis) and two continental regions (Mbacké and Linguère). This study is done using the RET Screen clean energy project management software climate data. The amount of electricity exported to the grid is calculated for each site. The results show that the climatic conditions of the coastal and continental regions are different from November to June. From July to October, which corresponds to the rainy season in Senegal, the climatic conditions of the coastal and continental regions are similar. The results also show that although the efficiency of photovoltaic modules is better on the coast, electricity production varies little from one site to another. Climate conditions in Senegal therefore have no impact on electricity production.
文摘The low electricity supply rate is a major cause of underdevelopment in Cameroon. To address this issue, Cameroon outlined a strategy in 2003 aiming for a production capacity of 3000 MW by 2020. However, by 2020, production had only reached 1040 MW, leading Cameroon to devise a new national energy sector development strategy targeting 5000 MW by 2035. This paper provides an overview of the current state of energy production and projects future output by 2035. Scientific articles and investigative reports on energy production in Cameroon have enabled an assessment of the current electrical energy production. The 2035 production estimate is based on the Energy Sector Development Projects (PDSEN) report in Cameroon. The current production is estimated at around 1600 MW. Considering the ongoing construction of power plants, future projects, and financing delays, achieving the 5000 MW goal by 2035 appears challenging. Nonetheless, diversifying energy production sources could bring Cameroon closer to this target.
基金Innovation Program of Shanghai Municipal Education Commission,China(No.13YZ139)Climbing Peak Discipline Project of Shanghai Dianji University,China(No.15DFXK01)
文摘It is important to distribute the load efficiently to minimize the cost of the economic dispatch of electrical power system. The uncertainty and volatility of wind energy make the economic dispatch much more complex when the general power systems are combined with wind farms. The short term wind power prediction method was discussed in this paper. The method was based on the empirical mode decomposition (EMD) and ensemble empirical mode decomposition (EEMD). Furthermore,the effect of wind farms on the traditional economic dispatch of electrical power system was analyzed. The mathematical model of the economic dispatch was established considering the environmental factors and extra spinning reserve cost. The multi-objective co-evolutionary algorithm was used to figure out the model. And the results were compared with the NSGA-Ⅱ(non-dominated sorting genetic algorithm-Ⅱ) to verify its feasibility.
基金Supported by the National Natural Science Foundation of China(52374067)PetroChina Scientific Research and Technology Development Project(2021ZG12)PetroChina Technology Project(2023ZZ09).
文摘To address the challenges associated with existing separated zone oil production technologies,such as incompatibility with pump inspection operations,short effective working life,and poor communication reliability,an innovative electromagnetic coupling intelligent zonal oil production technology has been proposed.The core and accessory tools have been developed and applied in field tests.This technology employs a pipe string structure incorporation a release sub,which separates the production and allocation pipe strings.When the two strings are docked downhole,electromagnetic coupling enables close-range wireless transmission of electrical power and signals between the strings,powering multiple downhole intelligent production allocators(IPAs)and enabling two-way communication.Core tools adapted to the complex working conditions downhole were developed,including downhole electricity&signal transmission equipment based on electromagnetic coupling(EST),IPAs,and ground communication controllers(GCCs).Accessory tools,including large-diameter release sub anchor and cable-crossing packers,have also been technically finalized.Field tests conducted on ten wells in Daqing Oilfield demonstrated that the downhole docking of the two strings was convenient and reliable,and the EST worked stably.Real-time monitoring of flow rate,pressure and temperature in separate layers and regulation of zonal fluid production were also achieved.This technology has enhanced reservoir understanding and achieved practical production results of increased oil output with reduced water cut.
