Results 11 to 20 of about 12,978 (169)
A Wireless Multi-Objective Power Sharing Method for Energy Storage System in DC Micro-Grid Considering Oscillatory-Type Power [PDF]
As the construction of new power systems, DC microgrids will become an important part of the distribution network. As AC load connecting to DC microgrids, the oscillating power will enter the DC system, which affects the power distribution of energy ...
LU Gang +4 more
core +1 more source
Gaoya dianqi, 2022 为提升柔性直流输电系统稳定性，一般在柔直单元逆变侧设置辅助直压环，当正、负极间直流电压跌落到一定阈值时，直流电压由逆变侧控制，整流侧输送固定有功功率，并为交流系统电压提供无功功率支撑。然而受环境或自身质量影响，高压直流分压器有可能产生故障，进而引发直流电压波动。当整流侧测量异常偏高时，引起逆变侧辅助直压环起动作，导致此时系统的整流侧和逆变测两端均控直流电压，直流系统输送功率失控，甚至发生反转。针对这一风险，文中基于RTDS的异步联网仿真平台，通过对测量值乘一个异常系数k来模拟直流电压电流测量异常 ...
罗炜, 谢超, 陈培龙
doaj
Gaoya dianqi, 2020 电力系统短路电流中直流分量的衰减时间常数超过现有断路器的标准时间常数将导致断路器实际开断能力下降,因此亟需研究直流分量对高压断路器的影响以准确评估其开断能力,防止开断失败造成重大损失。文中提出基于KEMA电弧模型研究SF6断路器直流分量开断能力的方法。首先,将KEMA模型引入直流分量开断仿真中,给出额定开断能力对应的临界电弧参数获取方法,然后使用临界参数仿真实际含更高直流分量的短路电流,最后用该方法验证宁夏电网断路器的实际开断能力。研究结果表明,当断路器的额定开断能力包含20%的直流分量时 ...
丁培 +6 more
doaj
Research on Methods of Modeling and Fault Diagnosis for Micro Direct-Current Motors [PDF]
, 2015 直流微电机以体积小、重量轻、便于控制等优点被广泛应用于生产消费领域，在微型精密仪器中尤为重要。为了保证产品出厂品质，生产过程必须对直流微电机进行100%检测。目前检测主要依靠人工的经验来判断电机的好坏，其工作量大，生产效率低，漏检现象严重，导致电机出厂质量不稳定。因此有必要寻找一种简便和可靠的直流微电机在生产线上的故障检测技术。该技术即可以对出厂前的直流微电机进行自动在线检测，以保证直流微电机的出厂合格率；又可以推广应用于其他永磁直流电机的故障检测与诊断。 通过分析空载下直流电机的动态数学模型 ...
谢志平
core
Application of Magnetic Coupling Resonance Wireless Power Transfer in Power System [PDF]
, 2022 Wireless power transfer (WPT) can transmit electric wirelessly. It performs better under some paticular circumstances compared with the traditonal transmission mode.
HE Hao +4 more
core +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The realization of bifunctional perovskite devices integrating photovoltaic (PV) and light‐emitting diode (LED) capabilities requires precisely controlled grain architectures to facilitate dual carrier transport pathways. In this work, sulfaguanidine (SG) molecules were introduced into the perovskite solution to reconstruct the crystallization
Jiong Li +7 more
wiley +1 more source
All-optical pattern matching system of 42 Gbit/s 4-bit BPSK signals and its demonstration for optoelectronic firewall [PDF]
, 2022 To achieve the all-optical pattern matching for optoelectronic firewall which could process high-speed optical signals efficiently, a BPSK all-optical pattern recognition system with the data rate up to 42 Gbit/s was proposed and demonstrated by ...
Lei GUO +5 more
core +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Chemically self‐charging aqueous zinc‐ion batteries (AZIBs) have emerged as promising candidates for energy storage technologies owing to their environmental autonomy and structural simplicity. Nonetheless, the self‐charging performance is significantly compromised by the limited potential difference between cathodes and oxygen, as well as the
Yan Wang +5 more
wiley +1 more source
Gaoya dianqi, 2023 温度分布是直流电缆运维检修的重要参数之一。由于高压直流输电起步较晚，高压直流电缆的研究不如交流电缆丰富、深入，因此对其温度分布影响因素的研究具有重要意义。通过Comsol有限元软件建立二维对称模型，计算±500 kV高压直流XLPE电缆稳态运行时的温度分布，求出适合电缆长期运行的载流量，并从载流量和环境温度两方面研究温度分布变化。仿真结果表明：载流量对温度分布变化具有较大的影响，当环境温度高于15℃时，导体温度约束载流量大小，环境温度低于15℃时，绝缘层最大允许温差约束载流量大小 ...
吴晶晶, 陈丽安, 严有祥, 赵鹏
doaj
Ultrasound in Obstetrics &Gynecology, Volume 67, Issue 3, Page 376-384, March 2026.ABSTRACT Objective To investigate whether combining abnormal morphological features observed on ultrasound in live pregnancies that ended in a first‐trimester miscarriage can predict an abnormal karyotype. Methods This retrospective observational cohort study was conducted at the early‐pregnancy assessment unit at University College London Hospital ...
T. Setty +5 more
wiley +1 more source