面向不间断供电(UPS)系统的电能质量分析技术

针对现行UPS电能质量检测过程存在的准确率低、实时性差且成本高的缺点,文中基于VMD-SAE-1DCNN模型提出了一种UPS电能质量检测与识别算法。对于电能信号非线性与非平稳的特点,使用变分模态算法对原信号进行分解,从而得到本征模态信号。同时,采用稀疏自编码器对本征模态信号进行特征提取,通过建立多层一维卷积神经网络模型对特征进行训练,提升了运算效率。实验测试结果表明,所提算法的迭代次数与运行时间在对比算法中均为最优,分类准确率可达97%以上,充分证明了改进算法的有效性。

The relationship between the high-frequency performance of supercapacitors and the type of doped nitrogen in the carbon electrode

Nitrogen doping has been widely used to improve the performance of carbon electrodes in supercapacitors,particularly in terms of their high-frequency response.However,the charge storage and electrolyte ion response mechanisms of different nitrogen dopants at high frequencies are still unclear.In this study,melamine foam carbons with different configurations of surfacedoped N were formed by gradient carbonization,and the effects of the configurations on the high-frequency response behavior of the supercapacitors were analyzed.Using a combination of experiments and first-principle calculations,we found that pyrrolic N,characterized by a higher adsorption energy,increases the charge storage capacity of the electrode at high frequencies.On the other hand,graphitic N,with a lower adsorption energy,increases the speed of ion response.We propose the use of adsorption energy as a practical descriptor for electrode/electrolyte design in high-frequency applications,offering a more universal approach for improving the performance of N-doped carbon materials in supercapacitors.

Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment

The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the foundation.The high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe cases.This article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element model.By proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through coupling.Taking into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are obtained.The validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance region.The design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel.

Review of the Analysis and Suppression for High-frequency Oscillations of the Grid-connected Wind Power Generation System

High-frequency oscillation(HFO)of gridconnected wind power generation systems(WPGS)is one of the most critical issues in recent years that threaten the safe access of WPGS to the grid.Ensuring the WPGS can damp HFO is becoming more and more vital for the development of wind power.The HFO phenomenon of wind turbines under different scenarios usually has different mechanisms.Hence,engineers need to acquire the working mechanisms of the different HFO damping technologies and select the appropriate one to ensure the effective implementation of oscillation damping in practical engineering.This paper introduces the general assumptions of WPGS when analyzing HFO,systematically summarizes the reasons for the occurrence of HFO in different scenarios,deeply analyses the key points and difficulties of HFO damping under different scenarios,and then compares the technical performances of various types of HFO suppression methods to provide adequate references for engineers in the application of technology.Finally,this paper discusses possible future research difficulties in the problem of HFO,as well as the possible future trends in the demand for HFO damping.

Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding

BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion.

UPS在医院系统中的应用

不间断电源(UPS)作为一种性能优良的供电设备,对医疗设备及数据运算、存储系统等的正常、安全、稳定运行起着重要的保障作用。文章研究广东省第二人民医院检验科UPS系统改造项目,该项目通过更换整套UPS设备及其安全管理系统,实现对UPS设备的实时监控与管理,有效减轻维护人员的压力,提高UPS设备的运行水平,为医院系统UPS设备全面升级改造提供参考。

广播电视制播工程项目中UPS的选用研究

对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电源设备技术架构成为一个关键问题。主要探讨了广播电视制播工程项目中UPS电源设备的选用,对UPS高频机和UPS工频机进行了比较分析,进而给出了广播电视制播工程中UPS电源设备的选用策略。

基于NB-IoT的UPS智能在线监测系统的设计

针对UPS机房在运行过程中无人监守,工作人员无法及时排查故障的问题,设计并实现了一套基于ARM和NB-IoT的UPS智能在线监测系统,由检测终端、云服务器和监管中心组成;检测终端使用各类传感器和检测电路获取多个UPS设备的输入输出电压和电流、负载率、蓄电池电量等数据以及机房温湿度环境参数,通过无线模块发送给云服务器,监管中心从云服务器获取数据,用户可以登录监管中心远程查询UPS的工作数据;经测试,系统能够实现对UPS各项数据的采集和无线传输,可以通过监管中心实时查询UPS工作状态以及下发指令,能达到实时监控的效果;具有数据测量准确,实时性响应良好等特点,减少了管理人员的工作量,提高了UPS的管理效率。

综合性医院UPS选型及运维关键问题探讨

通过文献研究法,根据应用场景差异,设计UPS选型流程,明确选型策略,同时借助信息化手段,以全生命周期运维为思路,在医院后勤智慧运维平台架构上拓展UPS运维模块,设计UPS巡检方案并实施,解决了UPS选型及运维过程中存在的问题,提升了运维效能。

电液3-UPS/S并联稳定平台参数振动特性分析

针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律,最后采用四阶龙格库塔法与模态试验对参数振动模型进行验证。结果表明:数值解与理论解之间的最大误差为4.20%,固有频率理论值与试验值之间的最大误差为4.66%,可验证参数振动模型的正确性。

中国先进研究堆UPS优化改进

中国先进研究堆(CARR)应急供电系统是为保障核反应堆的安全目标和运行目标而设置的重要系统,而1E级UPS是应急供电系统的核心设备,为了满足后续中国先进研究堆持续长时间安全稳定运行的要求,对UPS设备提出了升级优化要求。通过对UPS元件升级、增加防人因工具、优化风冷控制系统、优化变压器性能等方面提高应急供电系统的可靠性,使UPS能向安全系统有关设备提供充足的、质量合格的电力,为反应堆后续长期安全稳定运行夯实基础。

化工仪表UPS配置管理及维护探讨

不间断电源(UPS,Uninterrupted power supply),由电力变流器、储能装置(如蓄电池)和开关(电子式、机械式或混合式)等组合而成,在供电中断后能持续一定供电时间的电源设备[1]。随着技术的发展,UPS不间断电源应用范围逐渐扩大,特别在电信、石油、化工等领域得到了广泛的应用。石油化工企业生产装置电力设计技术规范规定一级负荷中当生产装置工作电源突然中断时,为确保安全停车,避免引起爆炸、火灾、中毒、人员伤亡、关键设备损坏,或事故一旦发生能及时处理,防止事故扩大,保证关键设备,抢救及撤离工作人员,而必须保证用电的负荷,应视为一级负荷中特别重要负荷,特别重要负荷必须设置UPS电源[2]。一般情况下,化工装置一级负荷都基本配备UPS电源,通过我司多年来对UPS电源应用过程中的经验,探讨化工仪表UPS电源的配置、管理、维护等要点问题,优化UPS配置,不断改善管理及维护能力。

基于UPS策略自我训练的半监督语义分割

为提高半监督语义分割的效果,文章提出一种损失归一化技术结合UPS策略的半监督语义分割网络SPNS。利用损失归一化技术缓解标准损失函数的自我训练不稳定问题;UPS策略是结合不确定性估计和消极学习的技术,通过计算输出值的不确定性作为另一种阈值,用以挑选可靠的伪标签,最后利用生成的伪标签和标记数据完成半监督语义分割任务。SPNS方法在PASCAL·VOC数据集上相对于只使用标记数据训练有着+2.06的效果提升,与其他方法相比也有一定提升。

UPS电控系统在降低海上平台电力关断风险中的应用

阐述钻采平台UPS系统的故障原因,通过对UPS系统馈线柜开关保护方式的优化升级,将欠压脱扣优化为分励脱扣,并对UPS电控系统、镍铬蓄电池备用电源系统优化,从而解决设计缺陷。

智能一体化UPS电源系统设计方案

广播电视发射的政策性、技术性及专业性较强,对于广播电视系统安全播出任务的要求日益严格,对发射台机房电源保障能力的要求也愈发严格。由于发射台机房停播故障70%以上源于供电系统,文章设计了智能一体化不间断电源(Uninterruptible Power Supply,UPS)系统方案,旨在避免广播电视发射台电源故障导致的停播事故,实现供配电系统零停播的要求和规范化、标准化、智慧化的用电目标。

基于电子电路原理的UPS故障分析与解决方案研究

不间断电源(Uninterruptible Power Supply,UPS)作为电力保障系统的重要组成部分,在现代电力系统中扮演着至关重要的角色。然而,由于UPS具有复杂的电子电路结构,在实际运行中常常面临各种故障问题,不仅影响系统的可靠性和稳定性,而且可能导致重大的经济损失和安全风险。因此,深入分析UPS故障,并提出有效的解决方案具有重要意义。文章通过研究基于电子电路原理的UPS故障分析与解决方案,梳理相关理论和实践经验,为UPS故障诊断与维修提供参考与指导。

浅谈医院UPS不间断电源安全管理问题及对策建议

UPS不间断电源是医院内部提供正常电源分配的重要基础,关系到医院急救类设备的正常使用和患者的生命健康,但同时也存在安全隐患,必须加强安全管理。本文通过总结安全巡检发现的安全隐患问题,包括UPS不间断电源性能问题,环境存在漏水和火灾隐患,以及临床使用部门日常保养中存在问题。分析医院安全管理方面的问题,可以归纳为部门间责权不到位、安全风险防范意识不足和保障措施不完善。建议通过明确部门间责权分配,通过宣传培训与绩效考核结合的方式提高员工安全风险意识,同时通过引入三级保养模式完善UPS不间断电源的性能保障措施。本文希望通过不断循序渐进的安全隐患排查行动提高医院设备安全管理水平。

Edge-Oriented Graphene on Carbon Nanofiber for High-Frequency Supercapacitors

High-frequency supercapacitors are being studied with the aim to replace the bulky electrolytic capacitors for current ripple filtering and other functions used in power systems. Here, 3 D edge-oriented graphene(EOG)was grown encircling carbon nanofiber(CNF) framework to form a highly conductive electrode with a large surface area. Such EOG/CNF electrodes were tested in aqueous and organic electrolytes for high-frequency supercapacitor development. For the aqueous and the organic cell, the characteristic frequency at-45° phase angle was found to be as high as 22 and 8.5 k Hz, respectively. At 120 Hz, the electrode capacitance density was 0.37 and 0.16 m F cm^(-2) for the two cells. In particular, the 3 V high-frequency organic cell was successfully tested as filtering capacitor used in AC/DC converter, suggesting the promisingpotential of this technology for compact power supply design and other applications.

Kinematic deformation and intensity assessment of the 2021 Maduo M_(S)7.4 earthquake in Qinghai revealed by high-frequency GNSS

Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advancement of GNSS observation and data processing makes it play an important role in this field,especially the high-frequency GNSS.We used the differential positioning method to calculate the 1 HZ GNSS data from 98 sites within 1000 km of the M_(S)7.4 Maduo earthquake epicenter.The kinematic deformation field and the distribution of the seismic intensity by using the peak ground velocity derived from displacement waveforms were obtained.The results show that:1)Horizontal coseismic response deformation levels ranging from 25 mm to 301 mm can be observed within a 1000 km radius from the epicenter.Coseismic response deformation on the east and west sides shows bilateral asymmetry,which markedly differs from the symmetry presented by surface rupture.2)The seismic intensity obtained through high-frequency GNSS and field investigations exhibits good consistency of the scope and orientation in the high seismic intensity area,although the former is generally slightly smaller than the latter.3)There may exist obstacles on the eastern side of the seismogenic fault.The Maduo earthquake induced a certain tectonic stress loading effect on the western Kunlun Pass-Jiangcuo fault(KPJF)and Maqin-Maqu segment,resulting in higher seismic risk in the future.

高频UPS在变电站交直流电源系统中的应用

高频UPS是高频开关电源技术在不间断电源领域的应用成果。其内部整流器与逆变器的开关频率高达几十甚至上百kHz,没有隔离变压器,整机效率更高,体积更小。在220kV及以下电压等级变电站交直流系统中,高频UPS的成本、体积、输出质量及工作效率等一系列指标优于工频机器,而其自身在负载能力、工作环境要求等方面的天然劣势也可以得到有效的规避。笔者认为应当加大高频UPS在低电压等级变电所中的应用,高频UPS在未来会如同高频开关电源取代线性电源一样逐步取代相应的工频产品。