Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electro...Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices,In this work,the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density threedimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte.Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure,the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L,as well as an excellent long cycle life(80% retention after 30,000 cycles at 10 A/g),which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors.This device,based on the fast ion adsorption/deso rption on the capacitor-type graphene cathode and reversible Zn^(2+) plating/stripping on the battery-type Zn anode,which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices.展开更多
The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The r...The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The resulting nickel oxide behaved as an electrochemicalcapacitor electrode with a specific capacitance (50-70 F/g) superior to most active carbonelectrodes. This kind of nickel oxide maintained high utilization at high rate of discharge (i.e.,high power density) and had excellent cycle life more than 1000 times, while the capacitance of thecell composed of two identical nickel oxide electrodes was poor at high discharge current densityand the maximum operational voltage of this type capacitor was limited to 0.5 V. A new typesuper-capacitor was designed in which the nickel oxide and the active carbon were applied to thepositive and negative electrodes respectively. The breakdown voltage of this type super-capacitorwas improved effectively to 0.8 V and excellent characteristic of high power discharge was attainedin this way. The Nickel oxide/KOH/Active carbon super-capacitor has promising potentials in portabletelecommunications, uninterruptable power supplies and battery load leveling applications.展开更多
新型电力系统和智能电网储能技术是实现“降碳、减排、节能”目标的重要路径,也是发展绿色经济和清洁能源的重要举措.对地铁列车能量调度及其制动能量回收与储存展开研究.首先,分析了超级电容器组和蓄电池组件混合储能技术原理和结构特...新型电力系统和智能电网储能技术是实现“降碳、减排、节能”目标的重要路径,也是发展绿色经济和清洁能源的重要举措.对地铁列车能量调度及其制动能量回收与储存展开研究.首先,分析了超级电容器组和蓄电池组件混合储能技术原理和结构特点.其次,改善列车制动能量回收率,加强荷电状态(State of Charge,SOC)调度过程的可控性和灵活性,为电能协同利用与回收提供安全运行保障和智能检测.实验与仿真结果表明,采用混合储能技术优化后的列车制动能量损失单位里程每小时降低2000 W,牵引网压电量回收率提升了15%,电流传输稳定效率提升8%,列车用电调度效率和SOC估算精准度分别提高了约10%和12%,有效验证该混合储能优化方案的可行性.展开更多
To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal v...To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal voltage regulation can be achieved in a DCMG simultaneously.The proposed control displays good plug-and-play features using only local measurements.For quantitative analysis and effective design of the critical parameter of unified control,two indices,equivalent power supporting time and inertia contributed by the unified controlled SC system,are introduced firstly.Then,with a simple but effective reduced-order model of a DCMG,analytical solutions are obtained for the two indices.In addition,a systematic design method is presented for the proposed unified control.Finally,to verify the proposed unified control,a switching model is developed for a typical DCMG in PSCAD/EMTDC,and theoretical analyses are conducted for different operating conditions.展开更多
为解决新型静止同步调相机(static var generator,SVG)+超级电容器(super capacitor,SSC)模型参数可靠性问题,研究SSC的大电网适用性,本文提出了一种针对SSC在弱受端电网补偿能力的建模方法与测试思路,利用ADPSS仿真平台对SSC的拓扑结...为解决新型静止同步调相机(static var generator,SVG)+超级电容器(super capacitor,SSC)模型参数可靠性问题,研究SSC的大电网适用性,本文提出了一种针对SSC在弱受端电网补偿能力的建模方法与测试思路,利用ADPSS仿真平台对SSC的拓扑结构与控制特性建模,以静止同步补偿器(static synchronous compensator,STATCOM)作为参照系对所建模型进行试验设计,通过仿真和实验结果验证并明确了SSC在所提策略下对弱受端电网稳定水平改善效果。展开更多
面向水电站场景,为解决传统黑启动方案响应慢、可靠性差以及经济性低等问题,将超级电容器(super capacitor,SC)与不间断电源(uninterruptible power supply,UPS)结合,构建一种基于SC的混合储能系统(hybrid energy storage system,HESS)...面向水电站场景,为解决传统黑启动方案响应慢、可靠性差以及经济性低等问题,将超级电容器(super capacitor,SC)与不间断电源(uninterruptible power supply,UPS)结合,构建一种基于SC的混合储能系统(hybrid energy storage system,HESS)黑启动装置.基于主从控制,提出了一种黑启动自适应柔性切换控制策略.作为主控单元,UPS采用电压/频率(voltage/frequency,V/F)控制持续提供电能支撑;作为从控单元,SC在黑启动阶段利用恒功率控制与虚拟同步发电机(virtual synchronous generator,VSG)技术提供大电流支撑.为保证HESS切换过程中稳定运行,采用一种改进预同步控制对相位和幅值进行预同步,实现HESS柔性平滑切换,同时提出一种可控硅整流器(silicon controlled rectifier,SCR)强制关断策略,实现HESS快速黑启动切换响应.仿真结果表明所提方法能够实现HESS黑启动平滑切换控制,实现毫秒级别快速响应,提高了水电站黑启动稳定性与经济性.展开更多
基金supported by the National Nature Science Foundations of China (No.21965019)the China Postdoctoral Science Foundation (No.2017M613248)+1 种基金the Natural Science Foundation of Gansu Province (No.1506 RJZA091)the Scientific Research Foundation of the Higher Education Institutions of Gansu Province (No.2015A-037)。
文摘Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices,In this work,the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density threedimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte.Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure,the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L,as well as an excellent long cycle life(80% retention after 30,000 cycles at 10 A/g),which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors.This device,based on the fast ion adsorption/deso rption on the capacitor-type graphene cathode and reversible Zn^(2+) plating/stripping on the battery-type Zn anode,which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices.
基金the National Natural Science Foundation of China (No.59807001).
文摘The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The resulting nickel oxide behaved as an electrochemicalcapacitor electrode with a specific capacitance (50-70 F/g) superior to most active carbonelectrodes. This kind of nickel oxide maintained high utilization at high rate of discharge (i.e.,high power density) and had excellent cycle life more than 1000 times, while the capacitance of thecell composed of two identical nickel oxide electrodes was poor at high discharge current densityand the maximum operational voltage of this type capacitor was limited to 0.5 V. A new typesuper-capacitor was designed in which the nickel oxide and the active carbon were applied to thepositive and negative electrodes respectively. The breakdown voltage of this type super-capacitorwas improved effectively to 0.8 V and excellent characteristic of high power discharge was attainedin this way. The Nickel oxide/KOH/Active carbon super-capacitor has promising potentials in portabletelecommunications, uninterruptable power supplies and battery load leveling applications.
文摘新型电力系统和智能电网储能技术是实现“降碳、减排、节能”目标的重要路径,也是发展绿色经济和清洁能源的重要举措.对地铁列车能量调度及其制动能量回收与储存展开研究.首先,分析了超级电容器组和蓄电池组件混合储能技术原理和结构特点.其次,改善列车制动能量回收率,加强荷电状态(State of Charge,SOC)调度过程的可控性和灵活性,为电能协同利用与回收提供安全运行保障和智能检测.实验与仿真结果表明,采用混合储能技术优化后的列车制动能量损失单位里程每小时降低2000 W,牵引网压电量回收率提升了15%,电流传输稳定效率提升8%,列车用电调度效率和SOC估算精准度分别提高了约10%和12%,有效验证该混合储能优化方案的可行性.
基金supported in part by the National Nature Science Foundation(No.51977142)National Key R&D Program of China(No.2020YFB1506803)Tianjin Natural Science Foundation(No.20JCQNJC00350)。
文摘To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal voltage regulation can be achieved in a DCMG simultaneously.The proposed control displays good plug-and-play features using only local measurements.For quantitative analysis and effective design of the critical parameter of unified control,two indices,equivalent power supporting time and inertia contributed by the unified controlled SC system,are introduced firstly.Then,with a simple but effective reduced-order model of a DCMG,analytical solutions are obtained for the two indices.In addition,a systematic design method is presented for the proposed unified control.Finally,to verify the proposed unified control,a switching model is developed for a typical DCMG in PSCAD/EMTDC,and theoretical analyses are conducted for different operating conditions.
