We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in t...We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under it.Compared with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the device.Furthermore,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also obtained.Simulation results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μm.Moreover,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,respectively.With the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,respectively.The proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON).展开更多
Nickel metal hydride battery in bipolar design offers some advantages for its application as a power storage system for electric and hybrid vehicles. This paper deals with the structure design and electrochemical stud...Nickel metal hydride battery in bipolar design offers some advantages for its application as a power storage system for electric and hybrid vehicles. This paper deals with the structure design and electrochemical studies of bipolar Ni/MH batteries for hybrid vehicles. An improvement is applied in bipolar battery design, and such bipolar Ni/MH batteries with 5 sub-cells have been assembled and investigated. Testing results show that bipolar batteries with improved structure have better compression tolerance and cycle performance than conventional ones. In addition, the improved bipolar batteries display excellent large current discharge ability and high power density. As simulating working conditions for hybrid vehicles, the batteries show good stability during pulse cycles, which verifies the possibility of being used as a power storage device on hybrid vehicles.展开更多
In the last years a variety of plasma sources have been developed for filmdeposition by plasma activated deposition techniques. In addition to RF- and DC-sources, pulsedplasma sources are gaining increased attention. ...In the last years a variety of plasma sources have been developed for filmdeposition by plasma activated deposition techniques. In addition to RF- and DC-sources, pulsedplasma sources are gaining increased attention. This interest is driven by the wish of depositingcoatings with superior properties as compared to those deposited by conventional techniques. Oneprominent example of coatings that are significantly enhanced by the usage of pulsed plasmas isalumina. Although crystalline o-alumina can be deposited by thermal CVD at temperatures above 1000deg C for two decades, no process for the deposition of crystalline alumina on heat sensitivesubstrates like tempered steels at low temperatures is commercially available up to now. In thispaper, the deposition of alumina films from gaseous mixtures of AlCl_3-N_2-H_2-Ar in a bipolarpulsed glow discharge at about 500 deg C is reported. Special attention was paid on the correlationbetween plasma characteristics and film properties. The measurements revealed that the properties ofthe resulting coatings were significantly influenced by the characteristics of the power supply.Depending on the gas composition and the plasma parameters, alumina films with high hardness andgood adhesion were deposited.展开更多
Interest in large-scale energy storage technologies has risen in recent decades with the rapid development of renewable energy.The redox flow battery satisfies the energy storage demands well owing to its advantages o...Interest in large-scale energy storage technologies has risen in recent decades with the rapid development of renewable energy.The redox flow battery satisfies the energy storage demands well owing to its advantages of scalability,flexibility,high round-trip efficiency,and long durability.As a critical component of the redox flow battery,the bipolar plates provide mechanical support for the electrodes and act as a physical separator between adjacent cells,as well as constructing the internal circuit and guiding the electrolyte flow.The present work offers a comprehensive review of the development of bipolar plates in redox flow batteries,covering materials,structures,and manufacturing methods.In terms of materials,the effects of material types and composition on the compactness,mechanical strength,and electrical conductivity are summarized in detail.Furthermore,the corrosion mechanisms of bipolar plates and the corresponding detection and mitigation methods are discussed.In addition,the structures of the bipolar plates refer to the flow field designs on the surface.The advantages and disadvantages of these existing flow fields are described,and the tendencies for further optimization are also discussed.The manufacturing of composite bipolar plates in terms of material cost and preparation methods is also outlined.Based on the summary of previous research,this work provides suggestions for the future development of high-performance bipolar plates.展开更多
为实现配电网的柔性互联,提出一种基于多绕组变压器的直接式AC-AC型智能软开关(direct AC-AC soft open point,AC-SOP)拓扑结构,可在四象限内独立控制输出电压的幅值及相位,且无直流环节,拓扑灵活性较高。建立AC-SOP互联馈线环网的数学...为实现配电网的柔性互联,提出一种基于多绕组变压器的直接式AC-AC型智能软开关(direct AC-AC soft open point,AC-SOP)拓扑结构,可在四象限内独立控制输出电压的幅值及相位,且无直流环节,拓扑灵活性较高。建立AC-SOP互联馈线环网的数学模型,并结合所提出的AC-SOP的等效占空比算法,给出AC-SOP在潮流控制模式和恢复供电模式下的闭环解耦控制策略。最后,通过仿真验证所提AC-SOP在控制互联馈线环网潮流和恢复供电方面的有效性;通过搭建单相1kW子模块,验证了所提拓扑结构可实现电压幅值与相位的独立控制。展开更多
基金the National Key Research and Development Program of China(Grant No.2018YFB1201802)the Key Realm R&D Program of Guangdong Province,China(Grant No.2018B010142001)the Guangdong Basic and Applied Basic Research Foundation,China(Grant No.2020A1515010128).
文摘We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under it.Compared with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the device.Furthermore,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also obtained.Simulation results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μm.Moreover,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,respectively.With the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,respectively.The proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON).
文摘Nickel metal hydride battery in bipolar design offers some advantages for its application as a power storage system for electric and hybrid vehicles. This paper deals with the structure design and electrochemical studies of bipolar Ni/MH batteries for hybrid vehicles. An improvement is applied in bipolar battery design, and such bipolar Ni/MH batteries with 5 sub-cells have been assembled and investigated. Testing results show that bipolar batteries with improved structure have better compression tolerance and cycle performance than conventional ones. In addition, the improved bipolar batteries display excellent large current discharge ability and high power density. As simulating working conditions for hybrid vehicles, the batteries show good stability during pulse cycles, which verifies the possibility of being used as a power storage device on hybrid vehicles.
基金The authors gratefully acknowledge the financial support of the Deutsche Forschungs-gemeinschaft (DFG) within the Collaborative Research Center (SFB).
文摘In the last years a variety of plasma sources have been developed for filmdeposition by plasma activated deposition techniques. In addition to RF- and DC-sources, pulsedplasma sources are gaining increased attention. This interest is driven by the wish of depositingcoatings with superior properties as compared to those deposited by conventional techniques. Oneprominent example of coatings that are significantly enhanced by the usage of pulsed plasmas isalumina. Although crystalline o-alumina can be deposited by thermal CVD at temperatures above 1000deg C for two decades, no process for the deposition of crystalline alumina on heat sensitivesubstrates like tempered steels at low temperatures is commercially available up to now. In thispaper, the deposition of alumina films from gaseous mixtures of AlCl_3-N_2-H_2-Ar in a bipolarpulsed glow discharge at about 500 deg C is reported. Special attention was paid on the correlationbetween plasma characteristics and film properties. The measurements revealed that the properties ofthe resulting coatings were significantly influenced by the characteristics of the power supply.Depending on the gas composition and the plasma parameters, alumina films with high hardness andgood adhesion were deposited.
基金the Basic Science Center Program for Ordered Energy Conversion of the National Natural Science Foundation of China(No.51888103)the National Key Research and Development Program of China(No.2017YFB0102703)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.51721004).
文摘Interest in large-scale energy storage technologies has risen in recent decades with the rapid development of renewable energy.The redox flow battery satisfies the energy storage demands well owing to its advantages of scalability,flexibility,high round-trip efficiency,and long durability.As a critical component of the redox flow battery,the bipolar plates provide mechanical support for the electrodes and act as a physical separator between adjacent cells,as well as constructing the internal circuit and guiding the electrolyte flow.The present work offers a comprehensive review of the development of bipolar plates in redox flow batteries,covering materials,structures,and manufacturing methods.In terms of materials,the effects of material types and composition on the compactness,mechanical strength,and electrical conductivity are summarized in detail.Furthermore,the corrosion mechanisms of bipolar plates and the corresponding detection and mitigation methods are discussed.In addition,the structures of the bipolar plates refer to the flow field designs on the surface.The advantages and disadvantages of these existing flow fields are described,and the tendencies for further optimization are also discussed.The manufacturing of composite bipolar plates in terms of material cost and preparation methods is also outlined.Based on the summary of previous research,this work provides suggestions for the future development of high-performance bipolar plates.
文摘为实现配电网的柔性互联,提出一种基于多绕组变压器的直接式AC-AC型智能软开关(direct AC-AC soft open point,AC-SOP)拓扑结构,可在四象限内独立控制输出电压的幅值及相位,且无直流环节,拓扑灵活性较高。建立AC-SOP互联馈线环网的数学模型,并结合所提出的AC-SOP的等效占空比算法,给出AC-SOP在潮流控制模式和恢复供电模式下的闭环解耦控制策略。最后,通过仿真验证所提AC-SOP在控制互联馈线环网潮流和恢复供电方面的有效性;通过搭建单相1kW子模块,验证了所提拓扑结构可实现电压幅值与相位的独立控制。
