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Networked Protection Scheme with Feeding Section as a Unit for High-speed Railway Traction Power Supply System

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1935-1941页

作者： Zhengqing Han Rui Shen Shuping Liu shibin gao the School of Electrical Engineering Southwest Jiaotong UniversityChengduChengdu 611756China

In order to rapidly clear a fault in all-parallel autotransformer(AT)railway system,the existing protection scheme trips both faulted line and healthy line.To solve this problem,a novel unit protection scheme is proposed in this paper.From fault characteristics measured at substation(SS),AT station(ATS)and section post(SP),we can observe that SS protective relays can detect all the faults but could not be selective,and ATS or SP relays can discriminate the faulted line but not sensitively enough;therefore,we make full use of the fault characteristics and propose a novel unit protection scheme.We employ directional distance protections at SS,ATS and SP,and unify them with networked inter-tripping signals and interlocking signals.When a forward distance protection detects a fault and does not receive inter-locking signals from reverse distance protections of other relays in a short setting time,it will trip the relevant circuit breaker and send an inter-tripping signal to other relays in the same protection unit.Field test results show the proposed scheme trips only the faulted line rapidly and never interrupts the power supply of healthy lines;therefore,the proposed protection scheme obtains both selectivity and speed.

关键词： All-parallel AT railway system distance protection unit protection

Fault diagnosis of high-speed train bogie based on LSTM neural network

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Science China(Information Sciences) 2021年第1期64卷 260-262页

作者： Deqing HUANG Yuanzhe FU Na QIN shibin gao Institute of System Science and Technology Southwest Jiaotong University National Rail Transit Electrification and Automation Engineering Technique Research Center Southwest Jiaotong University

Dear editor,With the extensive implementation of high-speed railway acceleration,higher requirements for safety and stability are put forward.In order to guarantee the safety of the highspeed train (HST),it is critical to detect the abnormal state in operation.Bogie that plays an important role in reducing vehicle vibration is connected to the track and the train body,and its health condition directly affects the safe operation of train.

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Adaptive droop control for better current-sharing in VSC-based MVDC railway electrification system

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 962-974页

作者： Salman AATIF Haitao HU Xiaowei YANG Yinbo GE Zhengyou HE shibin gao College of Electrical Engineering Southwest Jiaotong UniversityChengduChina National Rail Transit Electrification and Automation Engineering Technique Research Center Southwest Jiaotong UniversityChengduChina

The share of voltage source converter(VSC)technology is increasing in conventional power systems,and it is penetrating into specific transportation systems such as electric vehicles,railways,and ships.Researchers are identifying feasible methods to improve the performance of railway electrification systems(RESs)by utilizing VSC-based medium-voltage direct current(MVDC)railways.The continuous motion of electric trains makes the catenary resistance a variable quantity,as compared to the traction substation(TSS),and affects the currentsharing behavior of the system.A modified droop control technique is proposed in this paper for VSC-based MVDC RES to provide more effective current-sharing while maintaining catenary voltages above the minimum allowable limit.The droop coefficient is selected through an exponential function based on the ratio between the concerned TSS current and the system average current.This enables small adjustments of droop values in less concerning marginal current deviations,and provides higher droop adjustments for large current deviations.Meanwhile,the catenary voltages are regulated by considering the voltage data at the midpoint between two TSSs,which experiences the lowest voltages owing to the larger distance from the TSSs.The proposed techniques are validated via simulations and experiments.

关键词： Railway electrification Voltage source converter(VSC) Medium-voltage direct current(MVDC) Current-sharing Renewable energies in railways

Genetic architecture of maize yield traits dissected by QTL mapping and GWAS in maize

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The Crop Journal 2022年第2期10卷 436-446页

作者： Xiao Zhang Zhiyong Ren Bowen Luo Haixu Zhong Peng Ma Hongkai Zhang Hongmei Hu Yikai Wang Haiying Zhang Dan Liu Ling Wu Zhi Nie Yonghui Zhu Wenzhu He Suzhi Zhang Shunzong Su Yaou Shen shibin gao Maize Research Institute Sichuan Agricultural UniversityChengdu 611130SichuanChina Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region Ministry of AgricultureChengdu 611130SichuanChina Guangxi Qingqing Agricultural Technology CO. LTD.Nanning 530000GuangxiChina Biotechnology and Nuclear Technology Research Institute Sichuan Academy of Agricultural SciencesChengdu 610066SichuanChina Crop Research Institute Sichuan Academy of Agricultural SciencesChengdu 610066SichuanChina State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Chengdu 611130SichuanChina g College of Agronomy Sichuan Agricultural UniversityChengdu 611130SichuanChina

The study of yield traits can reveal the genetic architecture of grain yield for improving maize production.In this study, an association panel comprising 362 inbred lines and a recombinant inbred line population derived from X178 × 9782 were used to identify candidate genes for nine yield traits. High-priority overlap(HPO) genes, which are genes prioritized in a genome-wide association study(GWAS), were investigated using coexpression networks. The GWAS identified 51 environmentally stable SNPs in two environments and 36 pleiotropic SNPs, including three SNPs with both attributes. Seven hotspots containing 41 trait-associated SNPs were identified on six chromosomes by permutation. Pyramiding of superior alleles showed a highly positive effect on all traits, and the phenotypic values of ear diameter and ear weight consistently corresponded with the number of superior alleles in tropical and temperate germplasm. A total of 61 HPO genes were detected after trait-associated SNPs were combined with the coexpression networks. Linkage mapping identified 16 environmentally stable and 16 pleiotropic QTL.Seven SNPs that were located in QTL intervals were assigned as consensus SNPs for the yield traits.Among the candidate genes predicted by our study, some genes were confirmed to function in seed development. The gene Zm00001 d016656 encoding a serine/threonine protein kinase was associated with five different traits across multiple environments. Some genes were uniquely expressed in specific tissues and at certain stages of seed development. These findings will provide genetic information and resources for molecular breeding of maize grain yield.

关键词： Maize Yield traits Genome-wide association study(GWAS) Quantitative trait locus(QTL) Coexpression networks

A fault prediction method for catenary of high-speed rails based on meteorological conditions

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Journal of Modern Transportation 2019年第3期27卷 211-221页

作者： Sheng Lin Qinyang Yu Zhen Wang Ding Feng shibin gao School of Electrical Engineering Southwest Jiaotong University Chengdu 610031 China Laiwu Power Supply Company State Grid Shandong Electric Power Company Laiwu 271100 China

Fault frequency of catenary is related to meteo-rological conditions. In this work, based on the historical data, catenary fault frequency and weather-related fault rate are introduced to analyse the correlation between catenary faults and meteorological conditions, and further the effect of meteorological conditions on catenary oper-ation. Moreover, machine learning is used for catenary fault prediction. As with the single decision tree, only a small number of training samples can be classified cor-rectly by each weak classifier, the AdaBoost algorithm is adopted to adjust the weights of misclassified samples and weak classifiers, and train multiple weak classifiers. Finally, the weak classifiers are combined to construct a strong classifier, with which the final prediction result is obtained. In order to validate the prediction method, an example is provided based on the historical data from a railway bureau of China. The result shows that the mapping relation between meteorological conditions and catenary faults can be established accurately by AdaBoost algorithm. The AdaBoost algorithm can accurately predict a catenary fault if the meteorological conditions are provided.

关键词： High-speed rail Catenary Trip Fault prediction Data processing Meteorological conditions

电气化铁路分区所多功能潮流控制系统及其控制策略研究

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中国电机工程学报 2024年第12期44卷 4639-4651,I0005页

作者：王翼云胡海涛黄毅葛银波王科高仕斌郭旭刚西南交通大学电气工程学院四川省成都市611756 中国铁道科学研究院集团有限公司北京市海淀区100081

针对既有电气化铁路分段、分相式供电结构导致的列车过分相速度损失、再生制动能量利用率低等问题,提出一种分区所多功能潮流控制系统(multi-functional power flow control system for section post,SP-MPFC)及其控制策略,旨在充分利... 详细信息

针对既有电气化铁路分段、分相式供电结构导致的列车过分相速度损失、再生制动能量利用率低等问题,提出一种分区所多功能潮流控制系统(multi-functional power flow control system for section post,SP-MPFC)及其控制策略,旨在充分利用变流设备容量,兼顾实现分区所处列车柔性过分相、牵引网末端电压稳定与再生制动能量转移利用。首先,介绍分区所多功能潮流控制系统的拓扑结构。然后,详细分析了柔性过分相、牵引网末端电压稳定与再生制动能量转移利用3种功能的实现原理。在此基础上,提出分区所多功能潮流控制系统分层控制策略,其中能量管理层计算系统内各个变流器的有功/无功输出功率参考值,设备层协同控制多个变流器快速跟踪各自功率参考值。最后,通过仿真验证所提系统结构与控制策略的有效性。

关键词：电气化铁路分区所柔性过分相网压稳定再生制动能量

基于共溅射ZnO/SnO_(2)异质结薄膜的气体传感器研究

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传感器与微系统 2024年第2期43卷 61-64页

作者：孙士斌张叶裕高晨阳常雪婷上海海事大学物流工程学院上海201306 上海海事大学海洋科学与工程学院上海201306

采用射频磁控共溅射法在叉指电极上制备了ZnO/SnO_(2)n-n异质结复合薄膜,系统测试了其气敏特性,并分析了其气敏机理。结果表明,与ZnO薄膜和SnO_(2)薄膜气体传感器相比,ZnO/SnO_(2)异质结薄膜气体传感器具有更低的工作温度、更高的灵敏... 详细信息

采用射频磁控共溅射法在叉指电极上制备了ZnO/SnO_(2)n-n异质结复合薄膜,系统测试了其气敏特性,并分析了其气敏机理。结果表明,与ZnO薄膜和SnO_(2)薄膜气体传感器相比,ZnO/SnO_(2)异质结薄膜气体传感器具有更低的工作温度、更高的灵敏度以及更快的响应和恢复速度。ZnO/SnO_(2)异质结薄膜气体传感器对乙醇具有较好的选择性,最低检测体积分数为1×10^(-6),最佳工作温度为250℃;对1×10^(-4)乙醇气体的灵敏度可达18.4,响应时间和恢复时间分别为10 s和19 s。

关键词：磁控共溅射 ZnO/SnO_(2)异质结复合薄膜气体传感器

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用于薄层油气藏的聚丙烯酰胺全悬浮压裂液

油田化学 2024年第1期41卷 10-18页

作者：游兴鹏王历历高杨王世彬李健山赵金洲油气藏地质及开发工程全国家重点实验室(西南石油大学) 四川成都610500 中国石油长庆油田分公司油气工艺研究院陕西西安710018 中国石油集团川庆钻探工程有限公司页岩气勘探开发项目经理部四川成都610051

基于薄层油气资源开发中控制缝高和低排量的需求,以丙烯酰胺(AM)、丙烯酸(AA)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)、2-丙烯酰胺基乙基溴化铵(DAMAB)、烷基酚聚氧乙烯醚(NP-10)等为原料,通过水溶液自由基胶束聚合法合成聚丙烯酰胺嵌段共聚物... 详细信息

基于薄层油气资源开发中控制缝高和低排量的需求,以丙烯酰胺(AM)、丙烯酸(AA)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)、2-丙烯酰胺基乙基溴化铵(DAMAB)、烷基酚聚氧乙烯醚(NP-10)等为原料,通过水溶液自由基胶束聚合法合成聚丙烯酰胺嵌段共聚物(PMASD)。采用荧光分光光度计、流变仪和扫描电子显微镜研究了PMASD的临界缔合浓度、黏弹性和微观结构;同时,研究了PMASD压裂液的静态、动态携砂性能,并与聚丙烯酰胺滑溜水进行对比;最后,将PMASD压裂液进行了现场应用。结果表明,PMASD压裂液存在胶束结构,临界缔合浓度为0.127%。PMASD压裂液体系表现出较好的黏弹性,线性黏弹区范围为0.01~1.00 Pa,疏水缔合后强度大,抗剪切能力强。在低排量(20 L/min)的注入过程中,PMASD压裂液形成的网络结构呈无规则分布,具有很高的结构强度,可以有效携带支撑剂。PMASD压裂液的静态和动态携砂性能均较好。在砂液体积比为12%的实验条件下,PMASD质量分数≥0.25%(黏度为147 m Pa·s)时,在常温及80℃下均表现出较好的悬浮及携砂能力。相较于聚丙烯酰胺滑溜水,PMASD压裂液的携砂效果同比提高160%。在江苏油田X5-X井现场应用中,以2 m3/min的排量泵入PMASD压裂液,日产液由1.4 t增至6.5 t,日产油由0.6 t增至4.2 t,增产效果明显。全悬浮压裂液PMASD体系能满足薄层油气资源在低施工排量下有效携砂的压裂改造需求。

关键词：聚丙烯酰胺疏水缔合携砂性全悬浮压裂液薄层油气藏

生物炭和河沙对盐碱土壤水盐分布和小麦生长的影响

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甘肃农业大学学报 2024年第1期59卷 86-93页

作者：吴畏赵亚东高佩玲郭祥林王世斌山东理工大学农业工程与食品科学学院山东淄博255000 山东理工大学资源与环境工程学院山东淄博255000

【目的】探究生物炭与河沙对黄河三角洲地区盐碱土的改良效果。【方法】通过大田试验,分析了盐碱化土壤在生物炭和河沙作用下,土壤水盐的时空运移及冬小麦生长情况和产量。试验设置:CK、S1(136 t/(hm^(2)·a)河沙)、S2(272 t/(hm^(2)·a... 详细信息

【目的】探究生物炭与河沙对黄河三角洲地区盐碱土的改良效果。【方法】通过大田试验,分析了盐碱化土壤在生物炭和河沙作用下,土壤水盐的时空运移及冬小麦生长情况和产量。试验设置:CK、S1(136 t/(hm^(2)·a)河沙)、S2(272 t/(hm^(2)·a)河沙)、S3(408 t/(hm^(2)·a)河沙)、C1(5 t/(hm^(2)·a)生物炭)、C2(10 t/(hm^(2)·a)生物炭)、C3(20 t/(hm^(2)·a)生物炭)7个处理。【结果】对于土壤平均含水率,在0~20 cm土层C2处理最高为15.13%,在20~40、40~60 cm土层S3处理最高分别为17.35%、20.53%,生物炭和河沙处理均能影响土壤水分分布,前者主要增加表层土壤含水率,后者则对增加深层土壤含水率效果较好。而对于土壤含盐量,生物炭处理会增加初期的土壤含盐量,但返青期后含盐量会持续降低,土壤平均含盐量在0~20、20~40 cm土层S3处理最低,在40~60 cm土层C2处理最低。从冬小麦生育初期到收获期的含盐量变化来看,0~20、20~40、40~60 cm土层降盐率最高的处理分别为S2(32.34%)、C2(29.86%)、C1(12.38%),其中河沙处理在40~60 cm土层发生积盐。根据冬小麦生长和产量情况,生物炭与河沙均能促进冬小麦生长及增产,其中生物炭对促进冬小麦初期的生长有更好的效果,各处理中C2处理冬小麦产量最高,为5815.4 kg/hm^(2),比CK增产20.46%,S3处理产量为5795.1 kg/hm^(2),均显著高于CK。【结论】综上所述,对于盐碱土的改良效果,生物炭C2处理效果最好,河沙S3处理效果次之,可因地制宜选择合适的改良方法。

关键词：生物炭河沙盐碱土土壤含水率土壤含盐量冬小麦