Fiber-shaped supercapacitors(FSSCs)show great potential in portable and wearable electronics due to their unique advantages of high safety,environmental friendliness,high performances,outstanding flexibility and integ...Fiber-shaped supercapacitors(FSSCs)show great potential in portable and wearable electronics due to their unique advantages of high safety,environmental friendliness,high performances,outstanding flexibility and integrability.They can directly act as the power sources or be easily integrated with other flexible devices to constitute self-powered and sustainable energy suppliers,providing excellent adaptability to irregular surfaces.This review mainly summarizes the recently reported works of FSSCs including preparation methods of various fiber electrodes,construction strategies of FSSCs and multi-functional device integrations,exploration of reaction mechanisms and strategies to improve the electrochemical performance and provision of suggestions on further designing and optimization of FSSCs.Meanwhile,it shares our perspectives on challenges and opportunities in this field,shedding light on the development of high-performance fiber-shaped supercapacitors with multifunctions.展开更多
随着柔性直流电网的发展,其边界结构将发生改变,从“有边界电网”转变为“无边界电网”。如果在配置保护时,能够在原理上尽量适用于两种边界结构,则可以大大降低电网结构变化时保护验证的繁复性、提升保护应用的经济性。为提升线路行波...随着柔性直流电网的发展,其边界结构将发生改变,从“有边界电网”转变为“无边界电网”。如果在配置保护时,能够在原理上尽量适用于两种边界结构,则可以大大降低电网结构变化时保护验证的繁复性、提升保护应用的经济性。为提升线路行波保护对不同边界结构的适用性,该文提出一种新型的行波保护方案。该保护方案主要通过非故障极电流首行波积分(first current integration of non-fault pole,FCINP)实现。基于FCINP在不同边界结构电网下的距离特性和边界特性,可有效地提升保护在有边界电网和无边界电网下的故障识别性能,从而提升保护适用性。所提保护在基于PSCAD/EMTDC直流电网仿真模型中进行了性能验证。展开更多
Aiming at solving the problems existing in the landscape planning of waterfront areas in Yichang City,such as the contradiction of traffic organization,the waste of historical space resources and the insufficient util...Aiming at solving the problems existing in the landscape planning of waterfront areas in Yichang City,such as the contradiction of traffic organization,the waste of historical space resources and the insufficient utilization of hydrological characteristics,systematic renewal strategies were proposed.Through empirical research and spatial behavioral analysis,a renewal paradigm of“ecological restoration-cultural inheritance-spatial creation”was constructed according to topographic texture and hydrological characteristics.The innovation lies in proposing a renewal model of vertical corridors that integrates“transportation,ecology and landscape”,as well as a three-dimensional transportation scheme for separating pedestrians and vehicles based on the theory of alleviating spatial ownership contradictions.This study provides a technical path for improving the functions of high-density urban waterfront areas and optimizing their spatial efficiency,and has a practical value for enhancing citizens’water-friendly experiences and promoting cultural and tourism economy.展开更多
基于二阶广义积分器锁相环(second-order generalized integrator-phase-locked loop,SOGI-PLL)的图腾柱无桥功率因数校正变换器(totem pole bridgeless power factor correction,TBPFC)可有效滤除电网电压谐波,但对于包含谐波及直流分...基于二阶广义积分器锁相环(second-order generalized integrator-phase-locked loop,SOGI-PLL)的图腾柱无桥功率因数校正变换器(totem pole bridgeless power factor correction,TBPFC)可有效滤除电网电压谐波,但对于包含谐波及直流分量的复杂电网抑制谐波能力有限,锁相精确有待提高。为此提出4种改进SOGI-PLL的控制策略:嵌入型SOGI-PLL、级联型SOGI-PLL、并联型SOGI-PLL和增强并联型SOGI-PLL锁相设计方法。通过分别阐述4种策略的改进结构,将4种改进锁相方法与SOGI-PLL进行对比,分析出不同锁相策略的谐波及直流分量的抑制能力,并针对TBPFC变换器电流环比例积分控制器存在谐波抑制能力不足的问题,采用能够改善对电网谐波的抑制能力的比例积分谐振控制器,将该控制器与4种改进锁相环相结合重塑电流内环控制结构,实现谐波抑制,优化电感电流波形质量,降低总谐波失真。经仿真试验证明,与SOGI-PLL相比,所提出的4种改进策略的抑制谐波能力均优于SOGI-PLL,总谐波失真均低于SOGI-PLL。展开更多
提出了一种带PD输出电压瞬时值反馈内环的内模控制(internal model control,IMC)-PID电压型逆变电源控制方案:PD瞬时值反馈内环提高系统的动态性能,IMC-PID外环保证系统的稳态性能。给出了详细的基于极点配置的内环PD控制器和外环IMC-PI...提出了一种带PD输出电压瞬时值反馈内环的内模控制(internal model control,IMC)-PID电压型逆变电源控制方案:PD瞬时值反馈内环提高系统的动态性能,IMC-PID外环保证系统的稳态性能。给出了详细的基于极点配置的内环PD控制器和外环IMC-PID控制器设计步骤和方法。该方案只需检测输出电压,控制器结构简单,分析设计容易。仿真和实验结果表明该控制系统不仅具有优良的动、稳态性能,而且有很强的鲁棒性。相对电压、电流双环控制方案而言,该文提出的方案控制器结构和分析更加简单,成本更低,鲁棒性更强。展开更多
基金upported by the National Natural Science Foundation of China(No.21875226)the Science Fund for Distinguished Young Scholars of Sichuan Province(No.2017JQ0036)the Chengdu Rongpiao Talent plan,the Sichuan'Ten-thousand Talents Program",the"QianYingBaiTuan"Plan of China Mianyang Science City,the Science Foundation of Institute of Chemical Materials(No.O11100301)the"Global Experts Recruitment"program.
文摘Fiber-shaped supercapacitors(FSSCs)show great potential in portable and wearable electronics due to their unique advantages of high safety,environmental friendliness,high performances,outstanding flexibility and integrability.They can directly act as the power sources or be easily integrated with other flexible devices to constitute self-powered and sustainable energy suppliers,providing excellent adaptability to irregular surfaces.This review mainly summarizes the recently reported works of FSSCs including preparation methods of various fiber electrodes,construction strategies of FSSCs and multi-functional device integrations,exploration of reaction mechanisms and strategies to improve the electrochemical performance and provision of suggestions on further designing and optimization of FSSCs.Meanwhile,it shares our perspectives on challenges and opportunities in this field,shedding light on the development of high-performance fiber-shaped supercapacitors with multifunctions.
文摘随着柔性直流电网的发展,其边界结构将发生改变,从“有边界电网”转变为“无边界电网”。如果在配置保护时,能够在原理上尽量适用于两种边界结构,则可以大大降低电网结构变化时保护验证的繁复性、提升保护应用的经济性。为提升线路行波保护对不同边界结构的适用性,该文提出一种新型的行波保护方案。该保护方案主要通过非故障极电流首行波积分(first current integration of non-fault pole,FCINP)实现。基于FCINP在不同边界结构电网下的距离特性和边界特性,可有效地提升保护在有边界电网和无边界电网下的故障识别性能,从而提升保护适用性。所提保护在基于PSCAD/EMTDC直流电网仿真模型中进行了性能验证。
文摘Aiming at solving the problems existing in the landscape planning of waterfront areas in Yichang City,such as the contradiction of traffic organization,the waste of historical space resources and the insufficient utilization of hydrological characteristics,systematic renewal strategies were proposed.Through empirical research and spatial behavioral analysis,a renewal paradigm of“ecological restoration-cultural inheritance-spatial creation”was constructed according to topographic texture and hydrological characteristics.The innovation lies in proposing a renewal model of vertical corridors that integrates“transportation,ecology and landscape”,as well as a three-dimensional transportation scheme for separating pedestrians and vehicles based on the theory of alleviating spatial ownership contradictions.This study provides a technical path for improving the functions of high-density urban waterfront areas and optimizing their spatial efficiency,and has a practical value for enhancing citizens’water-friendly experiences and promoting cultural and tourism economy.
文摘基于二阶广义积分器锁相环(second-order generalized integrator-phase-locked loop,SOGI-PLL)的图腾柱无桥功率因数校正变换器(totem pole bridgeless power factor correction,TBPFC)可有效滤除电网电压谐波,但对于包含谐波及直流分量的复杂电网抑制谐波能力有限,锁相精确有待提高。为此提出4种改进SOGI-PLL的控制策略:嵌入型SOGI-PLL、级联型SOGI-PLL、并联型SOGI-PLL和增强并联型SOGI-PLL锁相设计方法。通过分别阐述4种策略的改进结构,将4种改进锁相方法与SOGI-PLL进行对比,分析出不同锁相策略的谐波及直流分量的抑制能力,并针对TBPFC变换器电流环比例积分控制器存在谐波抑制能力不足的问题,采用能够改善对电网谐波的抑制能力的比例积分谐振控制器,将该控制器与4种改进锁相环相结合重塑电流内环控制结构,实现谐波抑制,优化电感电流波形质量,降低总谐波失真。经仿真试验证明,与SOGI-PLL相比,所提出的4种改进策略的抑制谐波能力均优于SOGI-PLL,总谐波失真均低于SOGI-PLL。
文摘提出了一种带PD输出电压瞬时值反馈内环的内模控制(internal model control,IMC)-PID电压型逆变电源控制方案:PD瞬时值反馈内环提高系统的动态性能,IMC-PID外环保证系统的稳态性能。给出了详细的基于极点配置的内环PD控制器和外环IMC-PID控制器设计步骤和方法。该方案只需检测输出电压,控制器结构简单,分析设计容易。仿真和实验结果表明该控制系统不仅具有优良的动、稳态性能,而且有很强的鲁棒性。相对电压、电流双环控制方案而言,该文提出的方案控制器结构和分析更加简单,成本更低,鲁棒性更强。
