基于人工神经网络的整流电路故障诊断

提出了一种基于人工神经网络进行整流电路故障诊断的方法.分析了变频器整流电路的故障模式,提出了根据直流母线电压频谱作为神经网络的输入进行故障定位的方法,并进行了仿真研究.     

Fault detection and isolation for a nonlinear railway vehicle suspension with a Hybrid Extended Kalman filter

Fault detection is considered to be one way to improve system reliability and dependability for railway vehicles. The secondary lateral and anti-yaw dampers are the most critical parts in railway suspension systems. So far, the dampers have been modelled as linear components in the fault detection and isolation observer design. In this work, a Hybrid Extended Kalman filter is used to capture the nonlinear characteristics of the dampers. In order to detect and isolate faults, a nonlinear residual generator is developed, which can distinguish clearly between different types of faults. A lateral half train model serves as an example for the proposed technique. The results show that failures in the nonlinear suspension system can be detected and isolated accurately.     

A real-time impact detection and diagnosis system of catenary using measured strains by fibre Bragg grating sensors

This paper describes an impact detection system using strain signals based on fibre optic sensors(FBG) for the real-time monitoring of the catenary system. The proposed detection system consists of three subsystems: a measuring system, a data processing and analysis system, and a status display and data access system. Because the strain signals obey the normal distribution, to monitor the catenary system in real time, a novel method that combines mobile standard deviation with the mobile Pauta criterion is proposed to distinguish real impact from the strain signal background. The use of this adaptive judging method reduces the misjudgment rate of impacts and improves the impact recognition accuracy. These impacts can be identified by the data analysis system, which provides impact location and their causes using the features of the catenary system. This method can simplify the detection system compared with the traditional location method. An application to a commercial metro line system indicated that the impacts on the catenary system were main caused by overlaps, expansion joints or steady arms, and were verified by correspondence with the floor plan of the catenary and manual inspection results. These results verified the reliability and effectiveness of the proposed impact detection system.     

现代化驼峰气动调速设备动力系统节能分析

根据多年驼峰气动系统的工作经验,对现代化驼峰气动调速设备动力系统的能耗问题进行多方面的分析,并由此提出节约能耗的方法和手段,为路内各编组站驼峰气动系统的节能工作提供一定的参考和帮助。     

汽车空调系统性能优化研究

为优化某车型空调系统性能,本文通过环境模拟试验、系统台架试验、零部件台架试验手段,从鼓风机、蒸发器、膨胀阀匹配等方面提出性能提升方案。改进后的空调系统呼吸点温度在前20min与改进前相比较降低了6~7℃,优化方案实施效果良好。     

浅谈市区沥青路面病害成因及处治措施

道路是城市的动脉,沥青路面因其噪音低、舒适性高的特点得以在市区快速推广。该文以惠州市的市区沥青路面的病害为例,总结了市区沥青路面病害的特点、成因及处置维修措施。对城市沥青路面的管养维护总结了较丰富的实践经验,以供同行借鉴。     

船用柴油机故障诊断的综合法研究

文章针对当前船舶柴油机常用故障诊断方法的基本原理，总结了各种方法的优缺点，提出了故障诊断综合法。运用该方法对两起故障进行了分析，结果表明综合法对及时发现并排除故障是有效的，具有一定的现实意义。     

接触网可靠性研究方法浅析

介绍了国内外接触网可靠性研究的现状,分析了接触网的主要故障、接触网强度可靠性分析的计算模型和可靠性计算方法,对接触网可靠性研究存在的难点及其进一步研究的方向提出了几点建议。     

A comparison between two pneumatic suspension architectures

The aim of this work is to assess and compare the mathematical models of two pneumatic suspension architectures and show how they can converge, after appropriate simplifications, to a general linear form. After making this model dimensionless, it will be used to study, with a transmissibility analysis, the behaviour of a mono-suspension (quarter-car model). Finally, an example of a design process will be shown to highlight the strengths and weaknesses of both architectures and to provide the reader with a practical design tool.     

基于组合式BP网络的空压机故障诊断

针对空压机故障诊断过程中参数的多样性及复杂性,分别采用单BP网络和组合式BP网络两种方法对其主要故障进行建模和诊断。结果表明:采用组合式BP网络的故障诊断方法更加简单实用,能有效地提高空压机故障诊断的准确率。