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Raman spectroscopy based detection of corrosive sulfur in transformer oil:Method and application

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High Voltage 2022年第6期7卷 1175-1184页

作者： Ziyi wang Ruimin Song Weigen Chen Xinyuan Zhang pinyi wang State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina

In order to overcome the shortcomings of traditional methods for corrosive sulfur detection in transformer oil,Raman spectroscopy based detection is proposed in this paper.The widely concerned corrosive sulfur,Dibenzyl Disulfide(DBDS),was chosen as the characteristic molecule to be detected.A series of oil samples with different DBDS concentrations was prepared.And these samples were extracted by 1-methyl-2-pyrrolidinone for DBDS enrichment to improve the sensitivity of detection.Then Raman spectra of samples were obtained,and a linear model was established by analysing the relationship between the characteristic peak and the DBDS concentration.The limit of detection reached 7.98 mg/kg.For determining the DBDS concentrations causing sulfur corrosion,the sulfur weight content on the copper conductor surface was measured by Scanning Electron Microscope-Energy Dispersive Spectrometer after a corrosion test.The results show that the corrosion limitation highly depends on the type of transformer oil,and the Raman spectroscopy detection can meet the limit of detection requirement in practical condition.Finally,an on-site oil sample and five Lab-made samples were detected via our new method and the current Gas Chromatography-Mass Spectrometry based method.It is found that there is no significant divergence between the measurement results.And good applicability was also demonstrated in onsite sample test.

关键词： corrosion sulfur spectroscopy

Review of optical fibre sensors for electrical equipment characteristic state parameters detection

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High Voltage 2019年第4期4卷 271-281页

作者： Weigen Chen Jianxin wang Fu Wan pinyi wang State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044People's Republic of China

Optical fibre sensing technology is a powerful method for long-term reliable sensing in harsh environments,which means it is particularly suitable for the detection of electrical equipment characteristic state parameters,including characteristic gases,abnormal vibration,ultrasonic produced by partial discharge,and abnormal temperature rise.This paper reviews several individual optical fibre sensors for different state parameters detection,discusses the advantages,limitations and possible improvement methods,and finally presents the most promising optical fibre sensor for each state parameter.

关键词： fibre state electrical

A DYNAMIC SPECTRUM ACCESS NETWORK BASED ON COGNITIVE RADIO

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Journal of Electronics(China) 2010年第5期27卷 577-610页

作者： Ren pinyi wang Jun Li Shaoqian Department of Electronics and Information Engineering Xi＇an Jiaotong UniversityXi＇an 710049China

Dynamic spectrum access technologies based on Cognitive Radio(CR) is under intensive research carried out by the wireless communication society and is expected to solve the problem of spectrum scarcity.However,most enabling technologies related to dynamic spectrum access are con-sidered individually.In this paper,we consider these key technologies jointly and introduce a new implementation scheme for a Dynamic Spectrum Access Network Based on Cognitive Radio(DSAN-BCR).We start with a flexible hardware platform for DSAN-BCR,as well as a flexible protocol structure that dominates the operation of DSAN-BCR.We then focus on the state of the art of key technologies such as spectrum sensing,spectrum resources management,dynamic spectrum access,and routing that are below the network layer in DSAN-BCR,as well as the development of technologies related to higher layers.Last but not the least,we analyze the challenges confronted by these men-tioned technologies in DSAN-BCR,and give the perspectives on the future development of these technologies.The DSAN-BCR introduced is expected to provide a system level guidance to alleviate the problem of spectrum scarcity.

关键词： Cognitive Radio (CR) Dynamic Spectrum Access Network Based on Cognitive Radio (DSAN-BCR) Spectrum sensing Spectrum management Dynamic Spectrum Access (DSA) Cognitive routing

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A directional MAC protocol with long-range communication ability in ad hoc networks

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Science China(Information Sciences) 2012年第4期55卷 765-777页

作者： REN pinyi,FENG Jia & wang YiChen School of Electronics and Information Engineering,Xi’an Jiaotong University,Xi’an 710049,China School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an China

To address the problem that long-range communication capability in ad hoc networks using directional antenna is not generally utilized,a directional media access control (DMAC) protocol with long-range communication (LRC) capability in ad hoc networks is proposed.In the LRC-DMAC,the intermediate node uses a long-range orientation (LRO) algorithm to help the transmitter obtain the directional information of the receiver which is two hops away.Consequently,the long-range link between such two hops nodes can be set up.According to whether the received power information is available or not,we propose two types of LRO algorithm:without the received power information,a basic LRO obtains the approximate directional informa-tion of the long-range receiver by a geometric relationship;however,the LRO-PI can calculate the accurate directional information of the long-range receiver using the received power.Performance analysis indicates that the LRO algorithm achieves high accuracy when the relevant parameters are properly chosen.Simulation results show that the establishment of long-range links can effectively improve the network throughput and reduce the end-to-end delay.

关键词： ad hoc networks directional antenna MAC

变压器故障特征气体空芯反谐振光纤增强拉曼光谱检测

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中国电机工程学报 2022年第16期42卷 6136-6144页

作者：王建新陈伟根王品一张知先蔚超万福汤思蕊输配电装备及系统安全与新技术国家重点实验室(重庆大学) 重庆市沙坪坝区400044 国网江苏省电力有限公司江苏省南京市210024 重庆电力设计院有限责任公司重庆市渝北区401121

油中特征气体检测与分析是判断油浸式电力变压器早期潜伏性故障的有效方法之一。拉曼光谱技术具有利用单一波长的激光同时实现混合气体直接检测的独特优势。然而,拉曼信号弱导致气体检出限较高,无法满足变压器故障特征气体检测需求。鉴... 详细信息

油中特征气体检测与分析是判断油浸式电力变压器早期潜伏性故障的有效方法之一。拉曼光谱技术具有利用单一波长的激光同时实现混合气体直接检测的独特优势。然而,拉曼信号弱导致气体检出限较高,无法满足变压器故障特征气体检测需求。鉴于此,该文开展变压器故障特征气体空芯反谐振光纤增强拉曼光谱检测研究,对H、CO、CO、CH、CH、CH、CH等气体的检出限分别达到了8、22、5、2、6、3、3μL/L;结合最小二乘法,建立各气体特征拉曼峰峰面积与其浓度间的定量分析模型,并对配置的气体样品进行检测与分析。研究表明,光纤增强拉曼光谱技术具有高选择性、低检出限、高准确性及重复性,为变压器故障特征气体拉曼光谱在线监测与变压器故障诊断奠定了基础。

关键词：油浸式电力变压器故障特征气体拉曼光谱空芯反谐振光纤

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Rectangle blocking matrices based unitary multistage Wiener reduced-rank joint detection algorithm for multiple input multiple output systems

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Science China(Information Sciences) 2010年第10期53卷 2116-2126页

作者： REN pinyi 1 , wang Rui 2 & ZHANG ShiJiao 1 1 School of Electronic Engineering, Xi’an Jiaotong University, Xi’an 710049, China 2 Xi’an Monitoring Station, The State Administration of Radio Film and Television, Xi’an 710101, China School of Electronic Engineering Xi’an Jiaotong University Xi’an China Xi’an Monitoring Station The State Administration of Radio Film and Television Xi’an China

Traditional equalization algorithms for multiple input multiple output (MIMO) systems suffer from high complexity and low convergence rate. So an improved adaptive reduced-rank joint detection algorithm of multistage Wiener filter (MSWF) based on rectangle blocking matrices is proposed. The MSWF is implemented by the correlation subtraction algorithm (CSA) structure and is called unitary multistage Wiener filter (UMSWF). The new scheme adopts rectangle submatrix as blocking matrix, which is chosen from the square blocking matrix for UMSWF. The proposed algorithm can reduce the size of the observation data vectors step by step in the forward recursion decomposition of UMSWF. Thus, the computational complexity is reduced and the convergence rate is increased. Theoretical analysis and simulation results show that this improved adaptive reduced-rank joint detection algorithm of UMSWF based on rectangle blocking matrix has better performance such as lower complexity and faster convergence rate. In particular, simulations are conducted in the verticalBell Labs layered space-time (V-BLAST) system which adopts BPSK modulation, where 4 and 8 antennas are equipped at the transmitter and receiver, respectively. Compared with traditional equalization algorithm based on UMSWF, our new method can achieve the same BER performance at high SNR with only 0.5 times that of computational complexity.

关键词： multiple input multiple output (MIMO) systems unitary multistage Wiener filter (UMSWF) joint detection blocking matrix

基于频率锁定吸收光谱技术的变压器故障特征气体检测研究

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中国电机工程学报 2017年第18期37卷 5504-5510+5550页

作者：万福陈伟根王品一王建新王美林输配电装备及系统安全与新技术国家重点实验室(重庆大学)

高准确度、高灵敏度检测故障特征气体是基于油中溶解气体分析的变压器早期潜伏性故障诊断的关键。该文开展了基于频率锁定吸收光谱技术的变压器故障特征气体检测研究。基于电四极跃迁理论,论证了H;等同核双原子分子同样存在吸收效应;为... 详细信息

高准确度、高灵敏度检测故障特征气体是基于油中溶解气体分析的变压器早期潜伏性故障诊断的关键。该文开展了基于频率锁定吸收光谱技术的变压器故障特征气体检测研究。基于电四极跃迁理论,论证了H;等同核双原子分子同样存在吸收效应;为提高H;最小浓度的检测极限,搭建了频率锁定腔增强吸收光谱气体检测平台,首次实现了基于吸收光谱技术的变压器故障特征气体H;的定性与定量检测分析,检测准确度与重复性分别达到约93.82%及94.35%。腔内气体压强为101k Pa时,H;最小检测浓度的实验值约为7.5μL/L,与计算值的相对偏差仅为3.8%。此外,基于激光器阵列技术,实现了其他6种变压器故障特征混合气体CO、CO2、CH;、C;H;、C;H;与C;H;的吸收光谱检测,其检测准确度与最小检测浓度同样满足变压器油中溶解气体分析的需求。该研究为研制基于频率锁定吸收光谱技术的变压器故障特征气体现场检测系统提供了理论依据和技术支撑。

关键词：油中溶解气体分析 H2吸收谱线电四极跃迁频率锁定增强腔激光器阵列

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动车组故障预测与健康管理体系架构研究

智慧轨道交通 2022年第2期59卷 20-23页

作者：王中尧麻竞文王连富王品一刘健宇中车长春轨道客车股份有限公司国家工程研究中心吉林长春130062

近年来,随着全国大中城市轨道交通发展建设热潮的兴起,高速铁路运营总里程及车辆总数不断上升,列车车辆的复杂性及综合化不断提升,这对轨道交通车辆设备的安全性和维修的高效性提出了更高的要求。目前,我国的轨道车辆维修模式仍然采用... 详细信息

近年来,随着全国大中城市轨道交通发展建设热潮的兴起,高速铁路运营总里程及车辆总数不断上升,列车车辆的复杂性及综合化不断提升,这对轨道交通车辆设备的安全性和维修的高效性提出了更高的要求。目前,我国的轨道车辆维修模式仍然采用基于计划性维修和故障维修的事后维修方法,导致维修不足或过度维修,降低设备故障处理效率,增加维护成本。本文研究基于故障预测与健康管理(Prognostic and Health Management,PHM)的智能运维体系,利用列车多维度数据提前进行故障的可靠预测和精准维修,可以确保车辆的安全驾驶、低故障运营和高效率检修。

关键词：故障预测健康管理 PHM 智能运维精准维修动车组

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变压器油中气体拉曼光谱检测及信号处理方法

仪器仪表学报 2016年第11期37卷 2482-2488页

作者：万福杨曼琳贺鹏王建新王品一陈伟根重庆大学输配电装备及系统安全与新技术国家重点实验室

准确检测变压器油中溶解故障特征气体是诊断变压器运行状态的重要技术手段之一。论文基于拉曼光谱和腔长调制频率锁定原理,搭建了变压器故障特征气体频率锁定腔增强拉曼光检测平台,实现了H、CH、CH、CH、CH、CO、CO等七种故障特征气体... 详细信息

准确检测变压器油中溶解故障特征气体是诊断变压器运行状态的重要技术手段之一。论文基于拉曼光谱和腔长调制频率锁定原理,搭建了变压器故障特征气体频率锁定腔增强拉曼光检测平台,实现了H、CH、CH、CH、CH、CO、CO等七种故障特征气体的同时检测;1atm时,H、CH、CH、CH、CH、CO、CO的最小检测浓度实验值分别达到106、25、45、73、41、170、126(ppm)。频率锁定增强腔技术使最小检测浓度提高了约68倍。运用小波模极大值法对H的拉曼光谱检测信号进行了去噪处理,提出了基于包络线迭代法的光谱基线校正方法,校正后的光谱荧光背景残留减少,使气体拉曼光谱检测准确度提高了约2.95%,为变压器油中溶解故障气体同时准确检测提出了一种新方法。

关键词：变压器故障特征气体拉曼光谱检测频率锁定腔增强基线校正