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Interference mechanism analysis and mitigation measures with railway signalling equipment from harmonics in the traction system

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Transportation Safety and Environment 2020年第4期2卷 271-282页

作者： Zhiyu Li shanghe liu Shijiazhuang Tiedao University Shijiazhuang 050043China CRSC Research&Design Institute Group Co. Ltd.Beijing 100070China

With the development of high-speed railway and heavy-haul rail transport in China,a large number of new types of electric locomotives and electric multiple units have been put into operation,improving the efficiency and equipment quality of railway ***,harmonics emitted from the traction system and locomotives often interfere with the railway signalling equipment,which can lead to critical malfunction of the *** on field test data,this paper analyses the interference coupling mechanism and magnitude of traction harmonics to the signalling equipment using a three-element method of *** examines the three essential elements of electromagnetic interference,studies harmonic mitigation measures and proposes to solve the problem of inteference with signalling equipment by installing a passive high-pass filter in the coupling *** comparing the effects of several types of filters using simulation tests,this paper verified the validity of the method and concluded that a second-order passive filter is the optimal solution for harmonic interference mitigation.

关键词： heavy-haul railway traction harmonics interference signalling equipment

The Biological Property of Synthetic Evolved Digital Circuits with ESD Immunity - Redundancy or Degeneracy？

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Journal of Bionic Engineering 2013年第3期10卷 396-403,F0003页

作者： Menghua Man shanghe liu Xiaolong Chang Mai Lu Electrostatic & Electromagnetic Protection Institute Mechanical Engineering College Shijiazhuang 050003 P. R. China Key Laboratory of Opt-Electronic Technology and Intelligent Control of Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 P. R. China

In the ongoing evolutionary process, biological systems have displayed a fundamental and remarkable property of robustness, i.e., the property allows the system to maintain its functions despite external and internal perturbations. Redundancy and degeneracy are thought to be the underlying structural mechanisms of biological robustness. Inspired by this, we explored the proximate cause of the immunity of the synthetic evolved digital circuits to ESD interference and discussed the biological characteristics behind the evolutionary circuits. First, we proposed an evolutionary method for intrinsic immune circuit design. The circuits＇ immunity was evaluated using the functional fault models based on probability distributions. Then, several benchmark circuits, including ADDER, MAJORITY, and C17, were evolved for high intrinsic immunity. Finally, using the quantitative definitions based on information theory, we measured the topological characteristics of redundancy and degeneracy in the evolved circuits and compared their contributions to the immunity. The results show that redundant elements are neces- sary for the ESD immune circuit design, whereas degeneracy is the key to making use of the redundancy robustly and efficiently.

关键词： electromagnetic bionics electromagnetic protection electrostatic discharge synthetic evolved circuits redundancy degeneracy

The Immunity of Evolvable Digital Circuits to ESD Interference

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Journal of Bionic Engineering 2012年第3期9卷 358-366页

作者： shanghe liu Menghua Man Zhengquan Ju Xiaolong Chang Jie Chu Liang Yuan Electrostatic and Electromagnetic Protection Institute Mechanical Engineering College Shijiazhuang 050003 P. R. China Computer Engineering Department Mechanical Engineering College Shijiazhuang 050003 P. R. China

With the rapid development of semiconductor technology and the increasing proliferation of emission sources, digital circuits are frequently used in harsh and hostile electromagnetic environments. Electrostatic Discharge （ESD） interferences are gradually gaining prominence, resulting in performance degradations, malfunctions and disturbances in component and/or system level applications. Conventional solutions to such problems are shielding, filtering and grounding. This paper proposes a novel Evolvable Digital Circuit （EDC） for intrinsic immunity. The key idea is motivated by the noise-robustness and fault-tolerance of the biological system. First, the architecture of the EDC is designed based on the cell structure. Then, ESD immunity tests are carried out on the most fragile element of the EDC in operation. Based on the results, fault models are also presented to simulate different functional disturbances. Finally, the immunity of the EDC is evaluated while it is exposed to a variety of simulated environments. The results which demonstrate a graceful immunity to ESD interference are presented.

关键词： biomimetics electrostatic interference immunity evolvable digital circuits

Bio-Inspired Electromagnetic Protection Based on Neural Information Processing

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Journal of Bionic Engineering 2014年第1期11卷 151-157页

作者： Xiaolong Chang shanghe liu Menghua Man Weihua Han Jie Chu Liang Yuan Institute of Electrostatic and Electromagnetic Protection Mechanical Engineering College Shijiazhuang 050003 P R. China Institute of Semiconductors Chinese Academy of Science Beijing 100083 P. R. China Department of Information Engineering Mechanical Engineering College Shijiazhuang 050003 P. R. China

Electronic systems are vulnerable in electromagnetic interference environment. Although many solutions are adopted to solve this problem, for example shielding, filtering and grounding, noise is still introduced into the circuit inevitably. What impresses us is the biological nervous system with a vital property of robustness in noisy environment. Some mechanisms, such as neuron population coding, degeneracy and parallel distributed processing, are believed to partly explain how the nervous system counters the noise and component failure. This paper proposes a novel concept of bio-inspired electromagnetic protec- tion making reference to the characteristic of neural information processing. A bionic model is presented here to mimic neuron populations to transform the input signal into neural pulse signal. In the proposed model, neuron provides a dynamic feedback to the adjacent one according to the concept of synaptic plasticity. A simple neural circuitry is designed to verify the rationality of the bio-inspired model for electromagnetic protection. The experiment results display that bio-inspired electromagnetic pro- tection model has more power to counter the interference and component failure.

关键词： biological nervous system robustness population coding bio-inspired electromagnetic protection model neuralcircuitry

Reflection on methodology of the correlation between electromagnetic interference and safety in high-speed railway

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Railway Sciences 2024年第1期3卷 84-96页

作者： Chang liu Shiwu Yang Yixuan Yang Hefei Cao shanghe liu Department of Electromagnetic Environmental Effects Technology Studio CRSC Research and Design Institute Group Co.Ltd.BeijingChina School of Traffic and Transportation Shijiazhuang Tiedao UniversityShijiazhuangChina School of Automation and Intelligence Beijing Jiaotong UniversityBeijingChina Infrastructure Technology Research Institute CRSC Research and Design Institute Group Co.Ltd.BeijingChina Research Center for Electromagnetic Environmental Effects Shijiazhuang Tiedao UniversityShijiazhuangChina

Purpose – In the continuous development of high-speed railways, ensuring the safety of the operation controlsystem is crucial. Electromagnetic interference (EMI) faults in signaling equipment may cause transportationinterruptions, delays and even threaten the safety of train operations. Exploring the impact of disturbances onsignaling equipment and establishing evaluation methods for the correlation between EMI and safety isurgently ***/methodology/approach – This paper elaborates on the necessity and significance of studying theimpact of EMI as an unavoidable and widespread risk factor in the external environment of high-speed railwayoperations and continuous development. The current status of research methods and achievements from theperspectives of standard systems, reliability analysis and safety assessment are examined layer by ***, it provides prospects for innovative ideas for exploring the quantitative correlation between EMIand signaling *** – Despite certain innovative achievements in both domestic and international standard systems andrelated research for ensuring and evaluating railway signaling safety, there’s a lack of quantitative and strategic research on the degradation of safety performance in signaling equipment due to EMI. A quantitativecorrelation between EMI and safety has yet to be established. On this basis, this paper proposes considerationsfor research methods pertaining to the correlation between EMI and ***/value – This paper overviews a series of methods and outcomes derived from domestic andinternational studies regarding railway signaling safety, encompassing standard systems, reliability analysisand safety assessment. Recognizing the necessity for quantitatively describing and predicting the impact ofEMI on high-speed railway signaling safety, an innovative approach using risk assessment techniques as abridge to establish the correlation between EMI and signaling safety is proposed.

关键词： Electromagnetic interference Reliability Safety Risk assessment Signaling system High-speed railway

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电磁兼容与电磁防护相关研究进展

高电压技术 2014年第6期40卷 1605-1613页

作者：刘尚合刘卫东军械工程学院静电与电磁防护研究所石家庄050003

从内涵和外延上看,电磁兼容与电磁防护是一个有机的整体,其研究重点都是电磁环境对设备或系统的作用机理、能量耦合途径等,目的都是为了保障设备或系统在预定电磁环境中的生存能力和运行能力。围绕电磁干扰源、电磁能量耦合途径和敏感... 详细信息

从内涵和外延上看,电磁兼容与电磁防护是一个有机的整体,其研究重点都是电磁环境对设备或系统的作用机理、能量耦合途径等,目的都是为了保障设备或系统在预定电磁环境中的生存能力和运行能力。围绕电磁干扰源、电磁能量耦合途径和敏感对象这3个基本要素,重点从仿真建模、实验测试、防护措施等角度对国内外开展的相关研究工作进行了概述和分析,指出日益复杂的电磁环境、高度集成的电子设备及系统对电磁兼容与电磁防护研究提出了更高要求,即发展快速、准确、智能化的电磁干扰溯源技术,建立更大规模、更复杂系统在宽带范围内的电磁兼容预测模型,研究电磁能量主要耦合途径的分析确定方法和电磁环境效应的多物理场联合建模技术,推进电磁防护新技术、新材料、新器件的开发和工程化应用等已成为该领域的研究热点。

关键词：电磁环境电磁环境效应电磁兼容电磁干扰电磁防护电磁能量耦合敏感对象

基于小波分解与滑动峰态的微弱放电信号联合检测方法

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电力自动化设备 2016年第11期36卷 152-156,164页

作者：刘卫东刘尚合军械工程学院电磁环境效应国家级重点实验室河北石家庄050003

基于四阶累积量的滑动峰态算法在表征微弱信号的非高斯特性方面具有优势,可用于对微弱放电信号进行检测。但在混合噪声干扰下,受固定滑动窗宽度的影响,该算法对微弱放电信号的检测性能会显著劣化。针对该问题,提出了基于小波分解和滑动... 详细信息

基于四阶累积量的滑动峰态算法在表征微弱信号的非高斯特性方面具有优势,可用于对微弱放电信号进行检测。但在混合噪声干扰下,受固定滑动窗宽度的影响,该算法对微弱放电信号的检测性能会显著劣化。针对该问题,提出了基于小波分解和滑动峰态相结合的联合检测方法,并进行了仿真分析和实验验证,结果表明:利用小波变换对信号的多尺度分解以及信号在不同分解尺度上的特征差异,该联合检测方法实现了信号在多个优化的滑动窗宽度共同作用下的峰态检测,进一步增强了其抗噪声干扰能力,对微弱放电信号的检测性能相比原有滑动峰态算法有明显提升。

关键词：局部放电非接触式检测微弱信号非高斯信号小波分解滑动峰态

一种非线性元件实现线性放大的改进技术与仿真

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电波科学学报 2013年第2期28卷 309-315页

作者：刘成国杨国纬刘尚合武汉理工大学理学院射频与微波技术研究中心湖北武汉430070 军械工程学院静电与电磁防护技术研究所河北石家庄050003

提出了一种改进的非线性元件实现线性放大(Linear Amplifier Using Non-linear Components,LINC)理论,将幅度和相位均有变化的射频信号分离成包络信号和恒包络角调信号,将包络信号分两路反相调制到后者的相位中,对两路调制后的恒包络信... 详细信息

提出了一种改进的非线性元件实现线性放大(Linear Amplifier Using Non-linear Components,LINC)理论,将幅度和相位均有变化的射频信号分离成包络信号和恒包络角调信号,将包络信号分两路反相调制到后者的相位中,对两路调制后的恒包络信号进行变频放大,通过减法电路得到放大后的上变频输入射频信号.因为恒幅信号可以在放大器的非线性区放大而不失真,提高了整体效率高.推导出其电压增益为KG/Em,并对不同频率和幅度进行了仿真,仿真结果表明实现了理论分析预期的放大效果.

关键词：非线性元件实现线性放大(LINC) 射频功率放大器线性化效率增强技术

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不同辐射源瞬态电磁信号辐射场特性研究

电波科学学报 2015年第2期30卷 316-322页

作者：张悦刘尚合胡小锋刘卫东军械工程学院静电与电磁防护研究所河北石家庄050003

为研究不同辐射源瞬态电磁辐射信号辐射场特性,建立了圆柱形导体传输线模型,基于频域法对电晕放电的远场辐射场进行了理论计算,计算结果表明放电信号的时域波形衰减振荡时间随导体尺寸的增加而增大,辐射场频谱高频分量减少,且随着导体... 详细信息

为研究不同辐射源瞬态电磁辐射信号辐射场特性,建立了圆柱形导体传输线模型,基于频域法对电晕放电的远场辐射场进行了理论计算,计算结果表明放电信号的时域波形衰减振荡时间随导体尺寸的增加而增大,辐射场频谱高频分量减少,且随着导体长度的增加,辐射场振荡频率逐渐降低.设计瞬态电磁辐射信号测试实验,验证了理论计算结果.同时,实验采集了摩托车火花塞打火时的时域与频域信息,结果表明火花塞放电时域波形与电晕放电相近,但频谱差别很大,火花放电频谱能达到GHz以上.

关键词：瞬态电磁辐射传输线模型辐射场电晕放电火花放电