The development of aqueous zinc ion battery cathode materials with high capacity and high magnification is still a challenge.Herein,porous vanadium oxide/carbon（p-VO x @C,mainly VO 2 with a small amount of V 2 O 3 ） core/shell microspheres with oxygen vacancies are facilely fabricated by using a vanadium-based metal-organic framework（MIL-100（V）） as a sacrificial template.This unique structure can improve the conductivity of the VO x ,accelerate electrolyte diffusion,and suppress structural collapse during circulation.Subsequently,H 2 O molecules are introduced into the interlayer of VO x through a highly efficient in-situ electrochemical activation process,facilitating the intercalation and diffusion of zinc ions.After the activation,an optimal sample exhibits a high specific capacity of 464.3 mA h g -1 at0.2 A g -1 and 395.2 mA h g -1 at 10 A g -1 ,indicating excellent rate performance.Moreover,the optimal sample maintains a capacity retention of about 89.3% after 2500 cycles at 10 A g -1 .Density functional theory calculation demonstrates that the presence of oxygen vacancies and intercalated water molecules can significantly reduce the diffusion barrier for zinc ions.In addition,it is proved that the storage of zinc ions in the cathode is achieved by reversible intercalation/extraction during the charge and discharge process through various ex-situ analysis technologies.This work demonstrates that the p-VO x @C has great potential for applications in aqueous ZIBs after electrochemical activation.
变电站发生故障后断路器拒动可能会给区域电网带来功角稳定的问题.以山西电网500 kV明海湖变电站为例,在分析典型变电站发生故障后断路器拒动以及相关开关失灵保护参数设定对区域电网稳定问题影响的基础上,考虑500 kV明海湖变电站实际接线方式,用PSD-BPA仿真软件进行模拟,分析了不同故障下站内各开关拒动对区域电网稳定的影响,并结合仿真分析结果对相关断路器失灵整定时间的设置给出了相关建议.
±800 kV雁淮直流是山西电网跨区外送的重要通道,承担着新能源消纳、跨区电力互济的重要任务.雁淮直流的送电能力受雁门关换流站交流母线低电压约束、暂态压升约束及500 kV湖关三回线的热稳约束,其送电能力与配套电源的开机方式强耦合.当雁淮直流近区500 kV交流线路检修时,其送出能力受到了严重削弱,对电力保供、新能源消纳带来不利影响.提出了在交流线路检修方式下通过配置安控装置来提升送电能力的方案,并给出了相应的控制策略.
山西省电力现货市场下火电机组需要频繁启停调峰提高收益,但机组频繁启动不仅耗油量增加影响供电煤耗升高,而且也增加了二氧化碳排放量.对600 MW亚临界汽包锅炉进行了无启动炉机组启动试验,通过采用变更启动煤种、优化磨煤机启动边界参数、快速投入磨煤机运行等措施,使每次机组启动燃油耗量仅5 t,同时提出在一次风风道增加加热器的方案,使锅炉无启动炉冷态启动耗油量降至1t左右.这种启动方式不仅节能减排效果明显,而且还增强了机组在电力现货市场中的竞争力,对其他同类型机组启动节约燃油量有较好的借鉴作用.
在介绍某电厂氧化风管固定式空气喷雾器布置情况的基础上,结合其脱硫设计和运行情况存在的不足,分析了氧化风管堵塞的原因,提出了切除伸入氧化风母管的多余分支管、调整吸收塔内部分支管水平度、增加冲洗水系统以及检修孔等有效措施,有效遏制了氧化风管堵塞现象,确保了脱硫系统安全稳定及经济运行.
