Results 41 to 50 of about 9,264 (142)
超级电容储能和卸荷电路协调控制的永磁同步风电机组低电压穿越策略
针对永磁同步风力发电机组的低电压穿越问题,结合超级电容储能与卸荷电路的优点,提出了一种超级电容储能和卸荷电路协调控制的低电压穿越策略。当低电压故障发生时,在机组变流器的直流侧同时投入卸荷电阻和超级电容储能系统共同吸收故障期间的不平衡功率。在故障清除后,超级电容储能系统根据网侧变流器的运行状态将故障期间吸收的能量回馈电网。仿真结果表明,所提协调控制策略能在保证机组可靠实现故障穿越的同时,降低超级电容的设计容量和成本,并提高风能的利用率。
王雨欣 +6 more
doaj
Compression and energy absorption behavior of high entropy alloy syntactic foams
金属空心微球泡沫材料由于具有轻质,高比强度,高吸能性能等特点被广泛应用于轻质结构和吸能材料领域。因此,研发更高强度和吸能性能的金属空心微球泡沫材料并对其变形失效和吸能机理进行研究具有重要意义。本论文采用高熵合金作为基体,Al2O3空心陶瓷微球作为填充颗粒,利用渗流铸造法研发了两种新型金属空心微球泡沫材料,并对它们的静动态力学性能及变形破坏宏微观机理展开了系统的研究工作,取得的主要创新成果如下: (1)探索并优化了利用渗流铸造法制备高熵合金空心微球泡沫的工艺,确定了优选的预热温度及渗流压力 ...
孟锦
core
ABSTRACT The central challenge in the development of high‐performance electromagnetic wave‐absorbing materials lies in achieving an optimal balance between impedance matching and attenuation characteristics. This is particularly critical for purely dielectric absorbers, where precise tailoring of the real (ε′) and imaginary (ε″) parts of the complex ...
Zhixiao Wang +7 more
wiley +1 more source
介绍了对10kV合成套无间隙氧化锌避雷器重复吸收较大能量的耐受能力方面的试验研究结果。实测所得这雷器的泄漏电流随着重复吸收能量的大小和次数而变化的数据结果及变化原因的剖析,对估计无间隙氧化锌避雷器用于限制电弧接地过电压的可能性,有重要的参考价值。
高玉明, 杨立波
doaj
ABSTRACT Carbon dots (CDs) have emerged as promising modifiers for boosting the photocatalytic H2O2 production, yet their precise role remains to be quantitatively elucidated. Herein, S, N‐codoped lignin‐derived carbon dots (SN‐LCDs) and lignin‐derived carbon dots (LCDs) were synthesized and employed to modify TiO2.
Bin‐Peng Zhang +6 more
wiley +1 more source
通过对氧化锌电阻片承受短时过电压作用时的电气特性、能量吸收能力特性的研究,对氧化锌电阻片耐受短时过电压能力的评定方法提出讨论。对用变压器进行氧化锌电阻片短时过电压耐受能力试验出现残压波形畸变时,提出用等能量进行耐受时间等价性处理的办法。
李淑芳
doaj
Summary Fine roots are critical for soil resource uptake, yet how declining plant diversity alters fine root biomass (RB) and traits remains unclear. We tested how plant functional trait dissimilarity in shade tolerance, drought tolerance, growth rate, and nitrogen‐fixation ability drives variation in root attributes.
Sai Peng, Yakun Zhang, Han Y. H. Chen
wiley +1 more source
Read the free Plain Language Summary for this article on the Journal blog. Abstract Nitrogen (N) deposition strongly affects litter decomposition and nutrient release, thereby reshaping carbon cycling in terrestrial ecosystems. Although most studies have focused on above‐ground litter, the effects of N addition on fine root decomposition and their ...
Yuneng Wang +5 more
wiley +1 more source
基于换流站直流极线近区发生对地短路,直流滤波器的F1避雷器出现的冲击电流特征,分析了多次大电流冲击对F1避雷器用电阻片的性能影响。以平高东芝(廊坊)避雷器有限公司用于F1避雷器的两种电阻片为对象,研究了多次大电流冲击对电阻片老化特性、2 ms能量吸收能力以及保护特性的影响。验证了电阻片性能满足扎鲁特—青州±800 kV特高压直流工程需求。结果表明:多次大电流冲击对电阻片的能量吸收能力、老化特性以及保护性能没有明显影响。
姚玉锁 +6 more
doaj

