为了提高混合式直流断路器的开断能力,降低半导体器件的使用成本,提出了一种基于串联晶闸管强迫过零关断技术的具备双向开断能力的混合式直流断路器拓扑方案。在分析关断过程的基础上,推导了串联晶闸管阀与二极管阀组件反向恢复过程中...为了提高混合式直流断路器的开断能力,降低半导体器件的使用成本,提出了一种基于串联晶闸管强迫过零关断技术的具备双向开断能力的混合式直流断路器拓扑方案。在分析关断过程的基础上,推导了串联晶闸管阀与二极管阀组件反向恢复过程中均压回路的参数设计方法,然后以10 k V样机为例,开展了主支路和转移支路器件选型与参数设计,并搭建了10 k V直流断路器原理样机及其实验回路。研究结果表明：正常运行时,主支路由机械开关和少量的全控型半导体器件串联构成,其损耗较小;在开断电流时,故障电流首先转移至晶闸管阀支路,再通过放电回路注入反向电流迫使晶闸管阀过零关断,最后通过耗能支路吸收系统感性能量。原理样机实现了直流电压10 k V下短路电流峰值为8.8 k A的过零快速关断、且开断时间小于3 ms;转移支路可通过调整半导体器件的串联数量和选型大幅提升直流断路器的电压等级和故障电流耐受能力;串联二极管阀能在大电流关断暂态过程中抑制晶闸管器件的反向恢复过电压,降低晶闸管器件的损坏风险;在混合式直流断路器的换流和关断阶段,无需针对串联的晶闸管器件调整触发时间与匹配参数。综上所述,所提出的混合式直流断路器具有快速直流短路故障清除能力,可以作为未来柔性高压直流输电系统组网的工程实施方案之一。展开更多
The currently available 3D printing still cannot simultaneously deal with the metal and nonmetal inks together due to their huge difference in the melting points and poor compatible printability between each other. He...The currently available 3D printing still cannot simultaneously deal with the metal and nonmetal inks together due to their huge difference in the melting points and poor compatible printability between each other. Here through introducing the low melting point alloy Bi35In48.6Sn16Zno.4 and silicone rubber as functional inks, we proposed a compatible hybrid 3D printing method for manufacturing the desired device, the supporting substrate and the allied package structure together. The principle of pneumatic-typed 3D printing of multiple inks was described and typical physical properties of the ink Bi35In48.6Sn16Zno.4 were measured. Several key factors dominating the printing quality such as the temperature of the printing head, the air pressure exerted upon the liquid metal ink in the syringe, the moving velocity and the height of the printing head etc. were clarified. A general way of directly printing out 3D structured electronic devices consisting of both metal and nonmetal materials was demonstrated. Such hybrid objects were patterned and formed up layer by layer with Bi35In48.6Sn16Zno.4 alloy and silicone rub- ber which would become solidified after standing for a period of time under room temperature. To illustrate the compatible printability of these printing inks, a three-layer tricolor LED stereo circuit with controlled lighting capability was further man- ufactured and evaluated. The present study opens an important hybrid 3D printing way for directly manufacturing functional and structural end devices in an easy and low cost way.展开更多
Avariety of nonlinear circuits can be tamed to reproduce the main dynamical properties in neural activities for biological neurons while designing reliable artificial synapses for connecting these neural circuits beco...Avariety of nonlinear circuits can be tamed to reproduce the main dynamical properties in neural activities for biological neurons while designing reliable artificial synapses for connecting these neural circuits becomes a challenge.In this paper,a Josephson junction is used to build coupling channel for connecting two FitzHugh-Nagumo neural circuits driven by periodical voltage source.The hybrid synapse is designed by using a linear resistor paralleled with a Josephson junction,which can estimate the effect of external magnetic field by generating additive phase error between the junction.Indeed,it activates nonlinear coupling due to phase diversity in the Josephson junction.The coupled circuits are estimated in dimensionless dynamical systems by applying scale transformation on the variables and parameters in neural circuits.In fact,the intrinsic parameters of coupling channel are adjusted to detect the occurrence of synchronization.Bifurcation analysis is calculated to predict and confirm the occurrence of synchronization between two neural circuits.It is found that synchronization can be stabilized between two FHN neural circuits by selecting appropriate values for parameters in the Josephson junction involved in the coupling channel.It gives useful guidance for implementing artificial synapse for signal processing in neural circuits.展开更多
Constrained by the characteristics of neutral sec- tions (NS) and traditional vacuum circuit breakers, previous phase-controlled strategies have a long power supply dead time, it is difficult to realize a continuous p...Constrained by the characteristics of neutral sec- tions (NS) and traditional vacuum circuit breakers, previous phase-controlled strategies have a long power supply dead time, it is difficult to realize a continuous power supply to the auxiliary power system. The dead time can be reduced by using the ground automatic convert method, hybrid phase-controlled technologies can in theory completely eliminate inrush currents. In this paper, a new system based on hybrid phase-controlled switches is described and termed ground-switching passing neutral section system (GPNSS). The principle for restraining inrush currents is analyzed and strategies are carried out with the dead time limited to 5 ms. The characteristics of the vacuum circuit breaker are illustrated and the closing time window of the transformer is quantified. Through the use of mechanical switches and power electronics, the auxiliary power system may be continuously pow- ered. The prototype system is implemented and experimentally tested in the laboratory.展开更多
With the development of power electronic technologies and distributed power generation,DC distribution networks attract increasing attention due to their various advantages compared with traditional AC distribution ne...With the development of power electronic technologies and distributed power generation,DC distribution networks attract increasing attention due to their various advantages compared with traditional AC distribution networks.However,DC fault protection is one of the major issues in DC distribution networks.To improve their reliability and protect the semiconductor devices under DC faults,a current-limiting and energy-transferring DC circuit breaker topology is proposed in this paper.By applying passive components and thyristors,the proposed topology is capable of quickly limiting the fault current and transferring the faulty energy.The working principle,mathematical model and parameter designing method of the proposed topology are presented in this paper.The simulation results verify that the proposed DC circuit breaker could effectively limit the fault current and quickly interrupt the fault current.Cost and conduction power loss evaluation proves the practicality of the proposed topology in medium-voltage DC distribution networks.展开更多
Spin qubits and superconducting qubits are promising candidates for realizing solid-state quantum information processors.Designing a hybrid architecture that combines the advantages of different qubits on the same chi...Spin qubits and superconducting qubits are promising candidates for realizing solid-state quantum information processors.Designing a hybrid architecture that combines the advantages of different qubits on the same chip is a highly desirable but challenging goal.Here we propose a hybrid architecture that utilizes a high-impedance SQUID array resonator as a quantum bus,thereby coherently coupling different solid-state qubits.We employ a resonant exchange spin qubit hosted in a triple quantum dot and a superconducting transmon qubit.Since this hybrid system is highly tunable,it can operate in a dispersive regime,where the interaction between the different qubits is mediated by virtual photons.By utilizing such interactions,entangling gate operations between different qubits can be realized in a short time of 30 ns with a fidelity of up to 96.5%under realistic parameter conditions.Further utilizing this interaction,remote entangled state between different qubits can be prepared and is robust to perturbations of various parameters.These results pave the way for exploring efficient fault-tolerant quantum computation on hybrid quantum architecture platforms.展开更多
文摘为了提高混合式直流断路器的开断能力,降低半导体器件的使用成本,提出了一种基于串联晶闸管强迫过零关断技术的具备双向开断能力的混合式直流断路器拓扑方案。在分析关断过程的基础上,推导了串联晶闸管阀与二极管阀组件反向恢复过程中均压回路的参数设计方法,然后以10 k V样机为例,开展了主支路和转移支路器件选型与参数设计,并搭建了10 k V直流断路器原理样机及其实验回路。研究结果表明：正常运行时,主支路由机械开关和少量的全控型半导体器件串联构成,其损耗较小;在开断电流时,故障电流首先转移至晶闸管阀支路,再通过放电回路注入反向电流迫使晶闸管阀过零关断,最后通过耗能支路吸收系统感性能量。原理样机实现了直流电压10 k V下短路电流峰值为8.8 k A的过零快速关断、且开断时间小于3 ms;转移支路可通过调整半导体器件的串联数量和选型大幅提升直流断路器的电压等级和故障电流耐受能力;串联二极管阀能在大电流关断暂态过程中抑制晶闸管器件的反向恢复过电压,降低晶闸管器件的损坏风险;在混合式直流断路器的换流和关断阶段,无需针对串联的晶闸管器件调整触发时间与匹配参数。综上所述,所提出的混合式直流断路器具有快速直流短路故障清除能力,可以作为未来柔性高压直流输电系统组网的工程实施方案之一。
基金supported by the Research Funding of the Chinese Academy of Sciences(Grant No.KGZD-EW-T04-4)
文摘The currently available 3D printing still cannot simultaneously deal with the metal and nonmetal inks together due to their huge difference in the melting points and poor compatible printability between each other. Here through introducing the low melting point alloy Bi35In48.6Sn16Zno.4 and silicone rubber as functional inks, we proposed a compatible hybrid 3D printing method for manufacturing the desired device, the supporting substrate and the allied package structure together. The principle of pneumatic-typed 3D printing of multiple inks was described and typical physical properties of the ink Bi35In48.6Sn16Zno.4 were measured. Several key factors dominating the printing quality such as the temperature of the printing head, the air pressure exerted upon the liquid metal ink in the syringe, the moving velocity and the height of the printing head etc. were clarified. A general way of directly printing out 3D structured electronic devices consisting of both metal and nonmetal materials was demonstrated. Such hybrid objects were patterned and formed up layer by layer with Bi35In48.6Sn16Zno.4 alloy and silicone rub- ber which would become solidified after standing for a period of time under room temperature. To illustrate the compatible printability of these printing inks, a three-layer tricolor LED stereo circuit with controlled lighting capability was further man- ufactured and evaluated. The present study opens an important hybrid 3D printing way for directly manufacturing functional and structural end devices in an easy and low cost way.
基金This work was supported by the National Natural Science Foundation of China(Grant No.11765011)and the HongLiu First-Class Disciplines Development Program of Lanzhou University of Technology.
文摘Avariety of nonlinear circuits can be tamed to reproduce the main dynamical properties in neural activities for biological neurons while designing reliable artificial synapses for connecting these neural circuits becomes a challenge.In this paper,a Josephson junction is used to build coupling channel for connecting two FitzHugh-Nagumo neural circuits driven by periodical voltage source.The hybrid synapse is designed by using a linear resistor paralleled with a Josephson junction,which can estimate the effect of external magnetic field by generating additive phase error between the junction.Indeed,it activates nonlinear coupling due to phase diversity in the Josephson junction.The coupled circuits are estimated in dimensionless dynamical systems by applying scale transformation on the variables and parameters in neural circuits.In fact,the intrinsic parameters of coupling channel are adjusted to detect the occurrence of synchronization.Bifurcation analysis is calculated to predict and confirm the occurrence of synchronization between two neural circuits.It is found that synchronization can be stabilized between two FHN neural circuits by selecting appropriate values for parameters in the Josephson junction involved in the coupling channel.It gives useful guidance for implementing artificial synapse for signal processing in neural circuits.
文摘Constrained by the characteristics of neutral sec- tions (NS) and traditional vacuum circuit breakers, previous phase-controlled strategies have a long power supply dead time, it is difficult to realize a continuous power supply to the auxiliary power system. The dead time can be reduced by using the ground automatic convert method, hybrid phase-controlled technologies can in theory completely eliminate inrush currents. In this paper, a new system based on hybrid phase-controlled switches is described and termed ground-switching passing neutral section system (GPNSS). The principle for restraining inrush currents is analyzed and strategies are carried out with the dead time limited to 5 ms. The characteristics of the vacuum circuit breaker are illustrated and the closing time window of the transformer is quantified. Through the use of mechanical switches and power electronics, the auxiliary power system may be continuously pow- ered. The prototype system is implemented and experimentally tested in the laboratory.
基金This work is supported by National Key R&D Program(2018YFB0904600).
文摘With the development of power electronic technologies and distributed power generation,DC distribution networks attract increasing attention due to their various advantages compared with traditional AC distribution networks.However,DC fault protection is one of the major issues in DC distribution networks.To improve their reliability and protect the semiconductor devices under DC faults,a current-limiting and energy-transferring DC circuit breaker topology is proposed in this paper.By applying passive components and thyristors,the proposed topology is capable of quickly limiting the fault current and transferring the faulty energy.The working principle,mathematical model and parameter designing method of the proposed topology are presented in this paper.The simulation results verify that the proposed DC circuit breaker could effectively limit the fault current and quickly interrupt the fault current.Cost and conduction power loss evaluation proves the practicality of the proposed topology in medium-voltage DC distribution networks.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974336 and 12304401)the National Key R&D Program of China(Grant No.2017YFA0304100)+1 种基金the Key Project of Natural Science Research in Universities of Anhui Province(Grant No.KJ2021A1107)the Scientific Research Foundation of Suzhou University(Grant Nos.2020BS006 and 2021XJPT18).
文摘Spin qubits and superconducting qubits are promising candidates for realizing solid-state quantum information processors.Designing a hybrid architecture that combines the advantages of different qubits on the same chip is a highly desirable but challenging goal.Here we propose a hybrid architecture that utilizes a high-impedance SQUID array resonator as a quantum bus,thereby coherently coupling different solid-state qubits.We employ a resonant exchange spin qubit hosted in a triple quantum dot and a superconducting transmon qubit.Since this hybrid system is highly tunable,it can operate in a dispersive regime,where the interaction between the different qubits is mediated by virtual photons.By utilizing such interactions,entangling gate operations between different qubits can be realized in a short time of 30 ns with a fidelity of up to 96.5%under realistic parameter conditions.Further utilizing this interaction,remote entangled state between different qubits can be prepared and is robust to perturbations of various parameters.These results pave the way for exploring efficient fault-tolerant quantum computation on hybrid quantum architecture platforms.
