Establishment of a Quality Assurance System in the Online Monitoring of Electromagnetic Environment of Alternating Current Power Transmission and Transformation Facilities

With the acceleration of urbanization and increase of points in power systems,complaints about power grids have increased.In the actual on-site measurement process,although the actual measurement results can meet the relevant standards,some people are still concerned that the electromagnetic environment may change drastically outside the measurement period,which will have an impact on human health.In this study,the situation of electromagnetic online monitoring systems at home and abroad was introduced firstly,and then some practical requirements for establishing monitoring stations were analyzed.According to existing technologies and related writings,the methods and steps for establishing a quality assurance system were introduced,including the identification of quality assurance system activities and their corresponding structure of quality assurance system documents,the preparation and principles of the documents,and the operation of the quality assurance system.It intends to provide reference for the relevant organizations and personnel conducting electromagnetic environment monitoring when establishing a quality assurance system.Through the establishment of the online monitoring system and the later data publicity,the public have an intuitive understanding of the electromagnetic environment attenuation around power transmission and transformation projects,which can not only make China's electric power industry develop better,but also monitor the unexpected situation in time,maintain public safety and reduce people's fear of electromagnetic radiation in substations.

Compliance verification and probabilistic analysis of state-wide power quality monitoring data

This paper introduces the implementation and data analysis associated with a state-wide power quality monitoring and analysis system in China. Corporation specifications on power quality monitors as well as on communication protocols are formulated for data transmission. Big data platform and related technologies are utilized for data storage and computation. Compliance verification analysis and a power quality performance assessment are conducted, and a visualization tool for result presentation is finally presented.

A Remote Real-Time Monitoring System for Power Quality

An introduction is made to the composition, design method and engineering application of a remote real time monitoring system of power quality in substations based on internet. With virtual instrument and network technique adopted, this system is characterized by good real time property, high reliability, plentiful functions, and so on. It also can be used to monitor the load of a substation, such as electric locomotives.

Using Grey Target Theory for Power Quality Evaluation Based on Power Quality Monitoring Data

Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is proposed for power quality evaluation.The grey target is composed of power quality evaluation standard and power quality monitoring data to be evaluated.Combining with the characteristics of each power quality evaluation index,the target center of the whole grey target system is found.Then,the power quality monitoring data to be evaluated and the power quality standard mode are compared and analyzed to construct the power quality grey correlation difference information space.Finally,the target center coefficient and target degree of power quality are calculated to realize the comprehensive evaluation of power quality,and the evaluation grade of power quality monitoring data to be evaluated is obtained.Compared with the evaluation results of the existing literature,the effectiveness of the proposed method is verified,which shows that grey target theory is reasonable in the comprehensive evaluation of power quality.

Remote Visualization of High-Speed Rail Power Quality Monitoring

The visualization techniques were explored for power quality monitoring.And remote visualization solutions were proposed for highspeed rail power quality monitoring.Taking the Beijing-Shanghai highspeed rail power monitoring as a study case,a remote visualization client,based on our proposed solutions,was developed for high-speed rail power quality monitoring to efficiently support power quality data analysis of the electricity business.The solutions collected data from monitoring stations deployed along the high-speed rail route and visualized the data set with a variety of visualization technologies to alert the specific stations of catastrophic events.The proposed solutions have been proved to be effective in supporting decision-making for the railway power scheduling and providing diagnosis information for quickly spotting any possible runtime failure in operation.

The New Brazilian Power Quality Standard and a Low Cost Device Meter

This paper presents an overview about the new Brazilian Power Quality Standard and provides a low cost device PQ meter, developed and implemented to assist the national campaign to assess the Brazilian power quality indices, unknown until now. This work contributes with the search of a low cost devices PQ meter for a cost sensitive market, and introduces the new Brazilian Power Quality Standard to the international community.

Site Characterization Index for Continuous Power Quality Monitoring Based on Higher-order Statistics

The high penetration of distributed generation(DG)has set up a challenge for energy management and consequently for the monitoring and assessment of power quality(PQ).Besides,there are new types of disturbances owing to the uncontrolled connections of non-linear loads.The stochastic behaviour triggers the need for new holistic indicators which also deal with big data of PQ in terms of compression and scalability so as to extract the useful information regarding different network states and the prevailing PQ disturbances for future risk assessment and energy management systems.Permanent and continuous monitoring would guarantee the report to claim for damages and to assess the risk of PQ distortions.In this context,we propose a measurement method that postulates the use of two-dimensional(2D)diagrams based on higher-order statistics(HOSs)and a previous voltage quality index that assesses the voltage supply waveform in a continous monitoring campaign.Being suitable for both PQ and reliability applications,the results conclude that the inclusion of HOS measurements in the industrial metrological reports helps characterize the deviations of the voltage supply waveform,extracting the individual customers’pattern fingerprint,and compressing the data from both time and spatial aspects.The method allows a continuous and robust performance needed in the SG framework.Consequently,the method can be used by an average consumer as a probabilistic method to assess the risk of PQ deviations in site characterization.

A power-quality monitoring and assessment system for high-speed railways based on train-network-data center integration

In recent years,with the rapid development of high-speed railways(HSRs),power interruptions or disturbances in traction power supply systems have become increasingly dangerous.However,it is often impossible to detect these faults immediately through single-point monitoring or collecting data after accidents.To coordinate the power quality data of both traction power supply systems(TPSSs)and high-speed trains(HSTs),a monitoring and assessing system is proposed to access the power quality issues on HSRs.By integrating train monitoring,traction substation monitoring and data center,this monitoring system not only realizes the real-time monitoring of operational behaviors for both TPSSs and HSTs,but also conducts a comprehensive assessment of operational quality for train-network systems.Based on a large number of monitoring data,the field measurements show that this real-time monitoring system is effective for monitoring and evaluating a traction-network system.

Novel quantum-inspired firefly algorithm for optimal power quality monitor placement

The application of a quantum-inspired firefly algorithm was introduced to obtain optimal power quality monitor placement in a power system. The conventional binary firefly algorithm was modified by using quantum principles to attain a faster convergence rate that can improve system performance and to avoid premature convergence. In the optimization process, a multi-objective function was used with the system observability constraint, which is determined via the topological monitor reach area concept. The multi-objective function comprises three functions： number of required monitors, monitor over-lapping index, and sag severity index. The effectiveness of the proposed method was verified by applying the algorithm to an IEEE 118-bus transmission system and by comparing the algorithm with others of its kind.

基于在线监测时间序列数据的水质预测模型研究进展

当前地表水突发性污染事件频发,已造成严重的环境和社会影响,对环境监管部门应急处置能力建设提出了新要求和新挑战。地表水水质在线监测数据具有高频率和高时效等特点,系统论述了基于在线监测时间序列数据的水质预测模型的研究现状和进展,包括数据软测量、预处理方法和水质预测模型等,分析了不同水质预测模型在应用过程中存在的问题,并对未来研究方向进行了展望,以期为水质预测预警和环境监管提供技术支持和方法参考。

牵引变流器功率器件结温在线监测方法综述

功率器件结温在线监测对牵引变流器安全可靠运行至关重要,准确的结温监测是牵引变流器失效分析、运行状态监测、健康管理和剩余服役寿命预测的基础。因此,面向功率器件结温在线监测开展了大量研究。在此基础上,概述了以热网络模型法和温敏参数法为主的功率器件结温在线监测方法,以此为分类基准梳理了现有功率器件的结温监测方法并讨论了在牵引变流器中在线实现的可能,详细介绍了功率器件结温监测方法针对在线应用及客观因素干扰的发展与改进。最后,总结并对比了现有功率器件结温在线监测方法的演变、联系与差异,在分析现有结温监测方法面临挑战的基础上,展望功率器件结温在线监测在人工智能技术辅助下的前景。

企业何以提升治理质量?——基于网约车平台监管的制度分析

数字时代,由于技术壁垒等的存在,平台型企业行使监管权力成为一种政府的“刚需”。监管质量的提升离不开企业的参与。企业是追求盈利的市场组织,与追求公共利益的政府组织不同。传统理论强调企业的政治参与,或是企业作为治理主体之一,配合参与治理,对企业行使公共权力的现象缺少关注。如何保证企业有效行使公共权力,提升治理质量,成为一个重要的理论问题。中国网约车平台监管的制度建构和监管质量的提升,为分析这个问题提供了样本。研究发现:政府通过创造压力和动力,建立起松紧适度的“企业-政府”利益共同体,可以促使企业愿意且有效地行使公共权力,促成治理质量的提升。企业既需要适当的“嵌入性”,也需要适当的“自主性”,并构筑起合适的边界。关注企业行使公共权力的新现象,有助于进一步推进数字治理理论研究。

基于特征集重构与多标签分类模型的谐波源定位方法

传统基于谐波状态估计的谐波源定位方法需要专门的同步相量量测装置,工程应用受到限制。为此,基于电能质量监测装置所采集的非同步量测数据,提出了基于特征集重构与多标签分类模型的谐波源定位方法。利用监测数据的充分统计量来挖掘量测时段的谐波信息,同时利用标签特定特征学习算法重构特征集,从而消除冗余特征以及无关特征对于谐波源定位精度的影响;提出基于邻接矩阵以及灵敏度分析的测点配置方法,结合电路网络拓扑信息实现测点的优化配置;提出基于改进极限学习机的谐波源定位方法,该方法以重构特征集为输入,建立多标签分类模型,实现谐波源定位。通过仿真与算例分析,验证了所提方法的可行性及有效性。

基于DBSCAN聚类和区间回归的多谐波责任划分

在背景谐波阻抗变化和背景谐波电压波动的情况下,传统谐波责任划分方法难以适用于现有的统计型谐波监测数据,提出一种背景谐波变化下基于监测数据的多谐波责任划分方法。首先,构建谐波监测数据区间样本集,并建立背景谐波变化下的多谐波源区间谐波责任划分数学模型;其次,利用基于密度的聚类算法(DBSCAN)将采集到的统计型谐波数据集以簇为评价周期进行场景划分,并采用滑窗动态相关性分析方法筛选出满足线性关系阈值要求的数据;最后,利用基于参数化回归算法(PM)的区间线性进行方程参数计算并获取最佳样本划分方案,在构造的区间谐波责任划分基础上计算中长期时间范畴的谐波责任。利用实际电网中的谐波监测数据对所提方法进行验证,验证了该方法能利用现有的统计型谐波监测数据在背景谐波变化的情况下对每个谐波源进行合理时间尺度的谐波责任划分,可为实际电力系统运行过程中的多谐波责任划分提供一种新的思路。

基于多源数据的馈线谐波频谱估计方法

随着分布式电源和非线性负荷的投运规模不断增加,电网谐波污染愈加严重和复杂,有必要对各馈线谐波电流进行监测。但基于经济性考虑,对变电站所有馈线均进行谐波电流监测并不可行。针对上述问题,提出了基于多源数据的馈线谐波频谱估计方法。该方法基于电网现有电能质量监测系统、调度系统、营销业务应用系统等多源数据,只需对母线谐波电压和进线谐波电流开展监测,即可估计出变电站所有馈线的谐波电流情况。首先,根据馈线谐波电流的相量运算关系和功率关系构建馈线谐波频谱估计的目标函数。其次,基于多源数据利用改进粒子群算法求解目标函数,进而得到各馈线的各次谐波电流含有率及馈线谐波电流间的相角差,实现了各馈线谐波电流频谱的估计。最后,通过仿真算例和实测算例验证了方法的可行性。算例表明该方法仅需在变电站母线处安装一台电能质量监测终端,结合现有业务系统的基本电气数据等信息,可实现馈线谐波频谱的估计,有助于节约变电站监测装置的配置成本。

基于在线教学大数据的教学过程质量监控体系研究

教育信息化背景下,在线教学已然成为高校开展教学的主要形式。如何提取运用在线教学海量数据,挖掘分析其内在价值,促进数据与教学管理相融合,全面、及时、准确地把握在线教学质量,推动教育管理高效化、精准化、科学化发展非常值得探究。文章定位于中医药院校在线教学过程质量监控体系研究,以技术手段为支撑,以大数据分析为抓手,对相关案例进行剖析,试图搭建智能化的大数据在线教学质量监控平台,构建科学合理的在线教学过程质量监控体系,为提升高校教育管理效率和教育决策科学化水平提供一些借鉴和参考。

基于垂直中继的U型高压线路无线供电系统设计

为解决110 kV输电线路杆塔侧在线监测设备的供电问题,文中提出一种基于垂直中继的U型高压线路无线供电系统。首先结合互感耦合理论与有限元仿真,提出U型无线供电系统的整体设计方案,实现杆塔侧在线监测设备长距离、大功率、高效率、宽频带的无线供电。在此基础上建立系统级仿真模型,对U型无线供电系统的距离特性、频率特性、负载特性及电磁分布特性进行分析,验证了设计方案的可行性和电磁兼容性。最后搭建实验平台,在600 kHz的工作频率和1.2 m的传输距离下,系统输出功率达到73.58 W,能够满足杆塔侧在线监测设备的实际功率需求,为无线电能传输技术在高压设备供电领域的应用提供了参考依据。