With the growing popularity of electric vehicles(EV),there is an urgent demand to solve the stress placed on grids caused by the irregular and frequent access of EVs.The traditional direct current(DC)fast charging sta...With the growing popularity of electric vehicles(EV),there is an urgent demand to solve the stress placed on grids caused by the irregular and frequent access of EVs.The traditional direct current(DC)fast charging station(FCS)based on a photovoltaic(PV)system can effectively alleviate the stress of the grid and carbon emission,but the high cost of the energy storage system(ESS)and the under utilization of the grid-connected interlinking converters(GIC)are not very well addressed.In this paper,the DC FCS architecture based on a PV system and ESS-free is first proposed and employed to reduce the cost.Moreover,the proposed smart charging algorithm(SCA)can fully coordinate the source/load properties of the grid and EVs to achieve the maximum power output of the PV system and high utilization rate of GICs in the absence of ESS support for FCS.SCA contains a self-regulated algorithm(SRA)for EVs and a grid-regulated algorithm(GRA)for GICs.While the DC bus voltage change caused by power fluctuations does not exceed the set threshold,SRA readjusts the charging power of each EV through the status of the charging(SOC)feedback of the EV,which can ensure the power rebalancing of the FCS.The GRA would participate in the adjustment process once the DC bus voltage is beyond the set threshold range.Under the condition of ensuring the charging power of all EVs,a GRA based on adaptive droop control can improve the utilization rate of GICs.At last,the simulation and experimental results are provided to verify the effectiveness of the proposed SCA.展开更多
A multi-lens retroreflector with field curvature compensation was designed and used in an alignment-free distributed-cavity laser with a long working distance for resonant beam charging applications.The multi-lens des...A multi-lens retroreflector with field curvature compensation was designed and used in an alignment-free distributed-cavity laser with a long working distance for resonant beam charging applications.The multi-lens design,which makes use of off-the-shelf components,also allows a large field of view[FoV]without requirement of large element aperture.By implementing this design,an end-pumped 1063 nm Nd:GdVO4 laser could deliver over 5 W continuous-wave output power over a large range of working distances(1-5 m)and with ±30°receiver FoV under an incident diode pump power of 16.6 W.The output power fluctuation was less than 10%when moving and tilting the receiver over such a large range,without requiring any realignment of the cavity.展开更多
At present, the further development of new energy vehicles industry is hindered by limited consumer's participation or capital investment. Therefore, a new multilateral model of cross-industry alliance needs to ar...At present, the further development of new energy vehicles industry is hindered by limited consumer's participation or capital investment. Therefore, a new multilateral model of cross-industry alliance needs to arise. The advanced charging technology of Internetdistributed mobile energy can link up with many market participants closely and form an effective and multilateral win-win cross-industry alliance. This new industry alliance can realize unexpected multiple goals, for example,(1)consumers who have purchased new energy vehicles can avail free charging;(2) potential vehicle buyers can be encouraged to use new energy vehicles;(3) the new energy vehicle manufacturers can expand their production scale;(4) the new energy vehicles sellers(4 S shop) can expand their sales volume;(5) large shopping malls can attain more income;(6) financial institutions can absorb more deposits;(7) governments can further promote low-carbon traffic. This article analyzes the cross-industry alliance and its forming mechanism.1)展开更多
开发具有优异综合储能特性的无铅陶瓷电容器是脉冲功率技术领域的迫切需求。相较于其他无铅储能陶瓷体系,Na Nb O_(3)(NN)陶瓷具有结构相变丰富、理论密度低、电学可调性强、轻量化发展潜力大等显著优点,因而备受关注,成为当前的研究热...开发具有优异综合储能特性的无铅陶瓷电容器是脉冲功率技术领域的迫切需求。相较于其他无铅储能陶瓷体系,Na Nb O_(3)(NN)陶瓷具有结构相变丰富、理论密度低、电学可调性强、轻量化发展潜力大等显著优点,因而备受关注,成为当前的研究热点。基于降低容忍因子稳定反铁电相和增强陶瓷弛豫性的策略,开展了NN基弛豫反铁电陶瓷的制备与储能特性研究。通过引入BiFeO_(3)和Sr(Ti_(0.85)Zr_(0.15))O_(3)成功制备了0.9[0.9NaNbO_(3)-0.1BiFeO_(3)]-0.1Sr(Ti_(0.85)Zr_(0.15))O_(3)陶瓷,相较于纯NN陶瓷(0.14 J/cm^(3)、6.39%)和0.9NaNbO_(3)-0.1BiFeO_(3)陶瓷(3.55 J/cm^(3)和70.61%),其储能特性显著提升,储能密度(Wrec)与储能效率(η)分别达到了5.22 J/cm^(3)、83.92%。其优异的储能特性源于BiFeO_(3)和Sr(Ti_(0.85)Zr_(0.15))O_(3)掺杂对陶瓷的晶粒细化、反铁电相稳定性和弛豫特性的双增强机制。同时,0.9[0.9NaNbO_(3)-0.1Bi Fe O_(3)]-0.1Sr(Ti_(0.85)Zr_(0.15))O_(3)陶瓷表现出良好的温度及频率稳定性,是一种极具应用前景的电介质储能材料。展开更多
基金supported in part by the National Key Research and Development Program of China under Grant No.2017YFF0108800in part by the National Natural Science Foundation of China under Grant No.61773109in part by the Major Program of National Natural Foundation of China under Grant No.61573094。
文摘With the growing popularity of electric vehicles(EV),there is an urgent demand to solve the stress placed on grids caused by the irregular and frequent access of EVs.The traditional direct current(DC)fast charging station(FCS)based on a photovoltaic(PV)system can effectively alleviate the stress of the grid and carbon emission,but the high cost of the energy storage system(ESS)and the under utilization of the grid-connected interlinking converters(GIC)are not very well addressed.In this paper,the DC FCS architecture based on a PV system and ESS-free is first proposed and employed to reduce the cost.Moreover,the proposed smart charging algorithm(SCA)can fully coordinate the source/load properties of the grid and EVs to achieve the maximum power output of the PV system and high utilization rate of GICs in the absence of ESS support for FCS.SCA contains a self-regulated algorithm(SRA)for EVs and a grid-regulated algorithm(GRA)for GICs.While the DC bus voltage change caused by power fluctuations does not exceed the set threshold,SRA readjusts the charging power of each EV through the status of the charging(SOC)feedback of the EV,which can ensure the power rebalancing of the FCS.The GRA would participate in the adjustment process once the DC bus voltage is beyond the set threshold range.Under the condition of ensuring the charging power of all EVs,a GRA based on adaptive droop control can improve the utilization rate of GICs.At last,the simulation and experimental results are provided to verify the effectiveness of the proposed SCA.
基金This work was supported by the National Natural Science Foundation of China(Nos.61975146 and 62075159)Major Scientific and Technological Innovation Projects of Key R&D Plans in Shandong Province(No.2019JZZY020206)+1 种基金National Key R&D Program of China(No.2017YFF0104603)Foundation for Distinguished Young Scholars of China Academy of Space Technology(2021).
文摘A multi-lens retroreflector with field curvature compensation was designed and used in an alignment-free distributed-cavity laser with a long working distance for resonant beam charging applications.The multi-lens design,which makes use of off-the-shelf components,also allows a large field of view[FoV]without requirement of large element aperture.By implementing this design,an end-pumped 1063 nm Nd:GdVO4 laser could deliver over 5 W continuous-wave output power over a large range of working distances(1-5 m)and with ±30°receiver FoV under an incident diode pump power of 16.6 W.The output power fluctuation was less than 10%when moving and tilting the receiver over such a large range,without requiring any realignment of the cavity.
文摘At present, the further development of new energy vehicles industry is hindered by limited consumer's participation or capital investment. Therefore, a new multilateral model of cross-industry alliance needs to arise. The advanced charging technology of Internetdistributed mobile energy can link up with many market participants closely and form an effective and multilateral win-win cross-industry alliance. This new industry alliance can realize unexpected multiple goals, for example,(1)consumers who have purchased new energy vehicles can avail free charging;(2) potential vehicle buyers can be encouraged to use new energy vehicles;(3) the new energy vehicle manufacturers can expand their production scale;(4) the new energy vehicles sellers(4 S shop) can expand their sales volume;(5) large shopping malls can attain more income;(6) financial institutions can absorb more deposits;(7) governments can further promote low-carbon traffic. This article analyzes the cross-industry alliance and its forming mechanism.1)
文摘开发具有优异综合储能特性的无铅陶瓷电容器是脉冲功率技术领域的迫切需求。相较于其他无铅储能陶瓷体系,Na Nb O_(3)(NN)陶瓷具有结构相变丰富、理论密度低、电学可调性强、轻量化发展潜力大等显著优点,因而备受关注,成为当前的研究热点。基于降低容忍因子稳定反铁电相和增强陶瓷弛豫性的策略,开展了NN基弛豫反铁电陶瓷的制备与储能特性研究。通过引入BiFeO_(3)和Sr(Ti_(0.85)Zr_(0.15))O_(3)成功制备了0.9[0.9NaNbO_(3)-0.1BiFeO_(3)]-0.1Sr(Ti_(0.85)Zr_(0.15))O_(3)陶瓷,相较于纯NN陶瓷(0.14 J/cm^(3)、6.39%)和0.9NaNbO_(3)-0.1BiFeO_(3)陶瓷(3.55 J/cm^(3)和70.61%),其储能特性显著提升,储能密度(Wrec)与储能效率(η)分别达到了5.22 J/cm^(3)、83.92%。其优异的储能特性源于BiFeO_(3)和Sr(Ti_(0.85)Zr_(0.15))O_(3)掺杂对陶瓷的晶粒细化、反铁电相稳定性和弛豫特性的双增强机制。同时,0.9[0.9NaNbO_(3)-0.1Bi Fe O_(3)]-0.1Sr(Ti_(0.85)Zr_(0.15))O_(3)陶瓷表现出良好的温度及频率稳定性,是一种极具应用前景的电介质储能材料。
