Medium-voltage(MV)power electronics equipment has been increasingly applied m distnbution grids,and high-voltage(HV)silicon carbide(SiC)power semiconductors have attracted considerable attention in recent years.This p...Medium-voltage(MV)power electronics equipment has been increasingly applied m distnbution grids,and high-voltage(HV)silicon carbide(SiC)power semiconductors have attracted considerable attention in recent years.This paper first overviews the development and status of HV SiC power semiconductors.Then,MV power-converter applications in distribution grids are summarized and the benefits of HV SiC in these applications are presented.Microgrids,including conventional and asynchronous microgrids,that can fully demonstrate the benefits of HV SiC power semiconductors are selected to investigate the benefits of HV SiC in detail,including converter-level benefits and system-level benefits.Finally,an asynchronous microgrid power-conditioning system(PCS)prototype using a 10 kV SiC MOSFET is presented.展开更多
中国散裂中子源研发了一台射频四极RFQ(Radio Frequency Quadrupole)强流质子加速器。为保证RFQ顺利出束,对加工焊接阶段、RF调谐调场、高功率RF(Radio Frequency)老练过程中出现的问题进行了分析,给出了解决办法,并进行了调束实验。三...中国散裂中子源研发了一台射频四极RFQ(Radio Frequency Quadrupole)强流质子加速器。为保证RFQ顺利出束,对加工焊接阶段、RF调谐调场、高功率RF(Radio Frequency)老练过程中出现的问题进行了分析,给出了解决办法,并进行了调束实验。三坐标测量测得RFQ精加工后的加工公差约在20μm,RFQ腔体无载品质因子Q0大于7 679,约为理论无载Q0值的80%。RFQ腔内RF电场分布的平整度好于2.5%,RFQ高功率RF老练入腔功率达到450 k W,是理论腔耗390 k W的1.15倍,且保持连续12 h不打火。在RFQ调束实验中,RFQ出口得到3 Me V、28 m A的负氢束流,满足中国散裂中子源的要求。展开更多
大容量链式电池储能系统(battery energy storagesystem,BESS)是解决风力发电等可再生能源发电大规模并网问题的有效手段之一。针对BESS的功率调节系统(powerconditioning system,PCS)控制策略,在α-β静止坐标系下应用比例谐振(proport...大容量链式电池储能系统(battery energy storagesystem,BESS)是解决风力发电等可再生能源发电大规模并网问题的有效手段之一。针对BESS的功率调节系统(powerconditioning system,PCS)控制策略,在α-β静止坐标系下应用比例谐振(proportional resonant,PR)调节器实现瞬时功率无静差控制;通过注入零序电压实现相簇间荷电状态(stateof charge,SOC)均衡控制,并通过在各级联单元叠加相应交流电压实现相簇内各单元SOC均衡。仿真结果表明,采用该控制策略的PCS进行瞬时功率控制时具有较快的动态响应速度和较小的稳态误差,同时能有效实现SOC均衡控制,验证了该控制策略的正确性和可行性。展开更多
基金Supported by the DOE through Oak Ridge National Lab and the Power America Program,the Engineering Research Center Program of the National Science Foundation,and the CURENT Industry Partnership Program.
文摘Medium-voltage(MV)power electronics equipment has been increasingly applied m distnbution grids,and high-voltage(HV)silicon carbide(SiC)power semiconductors have attracted considerable attention in recent years.This paper first overviews the development and status of HV SiC power semiconductors.Then,MV power-converter applications in distribution grids are summarized and the benefits of HV SiC in these applications are presented.Microgrids,including conventional and asynchronous microgrids,that can fully demonstrate the benefits of HV SiC power semiconductors are selected to investigate the benefits of HV SiC in detail,including converter-level benefits and system-level benefits.Finally,an asynchronous microgrid power-conditioning system(PCS)prototype using a 10 kV SiC MOSFET is presented.
文摘中国散裂中子源研发了一台射频四极RFQ(Radio Frequency Quadrupole)强流质子加速器。为保证RFQ顺利出束,对加工焊接阶段、RF调谐调场、高功率RF(Radio Frequency)老练过程中出现的问题进行了分析,给出了解决办法,并进行了调束实验。三坐标测量测得RFQ精加工后的加工公差约在20μm,RFQ腔体无载品质因子Q0大于7 679,约为理论无载Q0值的80%。RFQ腔内RF电场分布的平整度好于2.5%,RFQ高功率RF老练入腔功率达到450 k W,是理论腔耗390 k W的1.15倍,且保持连续12 h不打火。在RFQ调束实验中,RFQ出口得到3 Me V、28 m A的负氢束流,满足中国散裂中子源的要求。
