As a ground transportation, the tram needs frequent speed regulation. Relying on mechanical braking when decelerating will cause excessive wear of the mechanical devices. Therefore, it is proposed to install a permanent magnet reduction device on the tram. In this paper, a permanent magnet deceleration device was designed without changing the original brake control system of the tram and its associated mechanism. The position of the magnetic pole of the permanent magnet was changed by the actuating mechanism to obtain different spatial magnetic fields, to achieve the purpose of obtaining different induced eddy currents and corresponding braking torques on the turntable, which achieved the conversion of braking and mitigation. Under the limited space of the tram, the structural size of the deceleration device and the braking torque of the deceleration target were derived. The mathematical model of the eddy current braking torque was established, and the influence of structural parameters on the braking torque was analyzed. The prototype was developed and the performance parameters were verified to meet the design requirements.

长期以来,列车制动系统在实验室内只能进行制动阀和制动系统静置试验,难以直接测试列车实际动态制动性能,因而对于长大货物列车制动性能及引起的纵向动力学效果难以判断.为此提出了基于滚动制动试验台进行车辆动态制动试验,即将虚拟列车制动系统模型与实际车辆制动系统组合,应用虚拟列车制动系统模型,通过计算机控制模拟不同编组列车的不同位置车辆的制动管路气压曲线,控制滚动制动试验台上单车做各种制动试验,以得出比较准确的列车各个车辆的实际动态制动效果.滚动制动试验台上车辆实际制动减速度和车辆前后拉杆承受的纵向力,为进一步评估各种编组列车制动纵向动力学性能提供了准确的依据,为长大货物列车运行安全提供了可靠的评估试验仿真装置.

针对高速列车在进一步发展过程中面临的轮轨黏着力不足的问题,基于电磁作用原理,提出一种电磁增压装置,利用电磁线圈在车轮和钢轨之间产生吸力,增加列车黏着力.首先建立电磁增压装置基本结构模型,进行电磁吸力计算,仿真分析研究列车速度、励磁电流、缠绕线圈形状和匝数分布、线圈距轨面高度等对电磁吸力的影响.研制了电磁试验装置对模型进行试验,验证了电磁场仿真结果的准确性,得到电磁吸力随速度、电流、线圈距轨面高度、线圈形状变化的规律.结果表明电磁增压装置能满足不同速度阶段的增加黏着力需求,并在需要时可对车轮添加反向励磁电流进行消磁.研究表明通过合理调节励磁电流大小可实现对转向架各车轮电磁吸力的稳定控制,可有效改善列车运行平稳性,提高列车运行的安全性.

随着铁路货车制动技术快速发展,新型控制阀不断涌现,列车编组辆数不断增加,传统的列车制动性能试验设备已经不能满足发展需要.引入计算机虚拟仿真技术,探索列车制动性能智能化试验方法及装备,是提升试验研究能力的必由之路.提出了基于虚拟仿真技术与实物试验台相结合的列车制动性能半实物仿真试验新思路.介绍了半实物仿真试验方法及技术方案、制动系统虚拟仿真模型建立、接口设备及控制系统研发、实物列车制动性能试验台研制及试验系统试验验证情况.

针对列车曲线通过安全性问题,设计了一种电磁增粘装置,通过增大轮轨间的垂向电磁吸力来增加轴重,从而改善列车曲线运行过程中的轮轨粘着关系,保障列车安全运行.在SIMPACK中建立CRH2型车动力学模型进行仿真分析,结果发现随着励磁电流的增加,列车曲线通过性明显改善.励磁电流的增大可以明显降低四个车轮的脱轨系数与轮轨垂向力和横向力,降低对钢轨的冲击力.在速度250～300 km·h-1的高速运行工况情况下,装有电磁增粘装置的转向架对脱轨系数的改善效果明显,脱轨系数降低6％左右.

随着经济不断发展,铁路向重载列车发展,现有室内制动试验都是静置试验.为了保证列车在制动过程中的安全性,提出了建立基于车辆滚动制动试验台的制动试验仿真系统基本思路,为了适用于车辆制动控制,将复杂的制动系统归纳出基本数学模型,结合列车实际制动时的工况,研究不同编组列车的不同位置车辆制动特性,对该系统的控制模型进行优化与完善,建立了制动试验仿真系统控制模型,实现在车辆滚动制动试验台上,模拟列车编组中任一辆车的制动试验.

设计了一种应用于有轨电车的永磁减速装置.基于永磁体移位形成不同磁路的基本原理,产生不同的磁场与涡流作用条件,分析永磁减速装置制动性能,建立了结构仿真模型.通过优化永磁体磁极厚度、转盘厚度和永磁体内外半径尺寸等主要结构参数,进行提高制动力矩分析演算.为验证仿真模型的有效性,研制试验样机.将制动转矩仿真值与试验值进行对比,制动转矩误差在5％以内.

针对磁悬浮列车线性涡流制动装置制动力不足的问题,对励磁电流和气隙等参数以及磁轭厚度、铁芯宽度和极距等结构参数进行分析.基于电磁场形态分析,采用脉冲电流作为激励形式,增大磁场作用范围,从而有效提高制动力.结果表明,在一定范围内,增加脉冲幅值能有效提高制动力,随着脉冲高电平幅值的增加,制动力明显减小;脉冲频率对制动力的影响较小;占空比越高,制动力越大.

针对列车牵引和制动时黏着力不足的问题,基于电磁作用原理提出一种安装在转向架上的新型电磁增黏装置。围绕高速旋转车轮,设置电磁线圈,建立电磁增黏装置基本结构模型,在车轮与钢轨之间形成电磁场,分析轮轨之间电磁作用力随列车速度的变化规律,以及电磁吸力对轮轨黏着力的影响。通过调整线圈高度和厚度比例及围绕车轮上下空间的布置,强化轮轨接触附近的磁场强度和磁力线分布,设计电磁增黏装置导磁外壳形式和气隙控制磁路的导向及作用范围,同时考虑车辆限界及安装条件,优化性能和结构参数。仿真结果表明,电磁增黏装置可以明显提高各个速度阶段轮轨之间垂向压力,增加轮轨黏着力;同时,通过调节两侧车轮压力,可提高列车运行平稳性。

With the rapid development of heavy haul freight train technology in China, especially the new type of freight car brake technology, the difficulty of air brake performance test for long formation trains is also increasing. The structural characteristics and design parameters of each truck brake are the same, and the performance of single vehicle test is the same, but the process of air pressure transmission is different under the condition of initial inflation of train tube and braking relief. By establishing the mathematical model of air pressure in train brake pipeline and combining the single valve and single vehicle physical test, the semi-physical simulation test platform of whole train about brake condition and mitigation condition was established. The hardware-in-the-loop test platform required that the simulation model was controlled in real time through hardware interface, and the model was revised according to the real data collected from the test to ensure the rationality and scientificity of the established test simulation model, and the brake aerodynamics equation was used for analysis and solution. In this paper, the aerodynamic partial differential equations method was used, and the characteristic line method and the gas volumetric charge and discharge model were used for analytical simulation calculation. Combined with the correction function for real-time correction, the real-time control of the semi-physical simulation test system was realized, which provided a theoretical basis for intelligent test platform and an ideal mathematical model.

The performance of the rotatory eddy current brake device directly affects the safety of train operation. Based on the change of the electromagnetic field vortex source density during the operation of the rotatory eddy current brake device, for improving its safety and reliability, main structural parameters such as the air gap size, the thickness of the turntable, the magnetic permeability of the core, the magnetic permeability of the turntable, the electrical conductivity of the turntable, the different currents and the arrangement of the magnetic poles of the eddy current brake device was adjusted to improve the braking torque and reduce the weight by means of simulation and experiment.

基于气体流动理论,依据气体状态方程和质量方程以及流量特性,建立货运列车制动系统再充气过程的数学模型,然后在智能化仿真试验平台上对该模型进行验证,试验所得曲线与仿真曲线基本吻合.考察150辆编组货运列车首车和尾车的再充气过程,得到了不同位置车辆再充气缓解过程的变化特征,并且测试出不同位置处车辆列车管与制动缸的作用时间差.

In order to adapt to the improvement of freight train braking technology, it is a good method to establish a semi‐physical braking intelligent test system, and the core technology of modeling and interface that supports the system is especially critical. Based on the above background, this paper is focus on the simulation modeling that reflects the braking performance characteristics of freight trains and designs the interface system that can be connected with the test equipment. Based on the analysis of the state equations of pressure gas during the braking process and the characteristics of fluid changes, this paper deduces a modular digital model of the braking machine that reflects the structural factors and the influencing factors of the process of fluid transfer. Then it combines the specific braking tests to verify the significance of the model and the effect of parameter changes on braking performance. The experimental results show the accuracy and feasibility of the modeling process, which provides a reference model establishing method and a research idea for the establishment of a more completed set of freight train braking system mathematical model. The design and implementation of this part of the technology also provide an important basis for the control part of the entire semi‐physical braking intelligent test system.

The system is based on aerodynamic power generation devices. The STM32 is the control core. A power management system suitable for heavy-duty trains is designed to solve the problem that heavy-duty trains cannot achieve electronically controlled air braking. Among them, the power management system detects the battery voltage current and temperature, and can accurately estimate the battery's remaining power through the Kalman filtering algorithm. The pneumatic power generation system in this paper is the basis of the electronically controlled air brake for heavy-duty trains, which provides the conditions for the future research on electronically controlled air brakes.

研究涡流电磁场的基本定律和作用关系,探究感应盘上的涡流电磁场的基本特征,对静态磁场在旋转导体上产生的涡流以及涡流感应电场对磁场的影响进行分析.从计算衍生电磁场涡旋源密度变化对磁电作用的影响,提出了周期变化的涡流感应电场对励磁线圈电流影响即产生互感效应的推论.推导涡流制动过程中旋转磁场变化特征,并对制动盘上感生电流即涡流分布进行分析.

In the electro-pneumatic breaking system,the dynamic performance of the electro-pneumatic brake solenoid valve directly determines the train safety.To improve the sensitivity and reliability,the solenoid valve armature clearance,coil turns,spring preload and other major structural parameters were adjusted based on the law of electromagnetic wave energy flow fluctuation and its influence on the dynamic characteristics of valve during action process.The dynamic electromagnetic field range of changes was controlled,and the performance parameters were optimized.It is found that the electromagnetic field energy output was reduced and the operating temperature rising velocity was decreased.

In order to establish a mathematical model of the air brake that can reflect the braking performance characteristics of the wagon braking system,and to analyze the working process of wagon brake under various working conditions,the brake model was divided into corresponding functional modules.Based on the deconstruction of the balance of fluid action in the brake pipe of each module,and the derivation of the gas state equations,the mathematical models were established for the decompression of the train pipe and for the pressurization of the brake cylinder under common brake module.The mathematical models were combined with the wagon brake system to establish a simulation model.The influence of brake structural parameters on the braking performance was analyzed.Then a modular braking model which can reflect the structural factors and influencing factors of the fluid transfer process was established.Through test results,the accuracy and feasibility of the modelling process were verified.Finally,combined with the models and tests,the impact of different positions of the vehicles of a long train on the brake performance was obtained.It provides a reference modeling method and a research thinking idea for the establishment of a more complete set of mathematical models for the wagon braking system.

利用所设计板件焊接试验台对两1 mm厚一系铝板进行了电磁焊接试验,利用扫描电子显微镜(SEM)对样件波状焊接界面的微观形貌进行观察.为解释其形成原因,对电磁焊接过程中两被焊板件的撞击过程进行3D数值模拟,获得该过程中飞板所受垂向应力变化规律及撞击速度变化曲线,仿真结果与试验所观察现象相符.通过分析焊接接头界面和撞击点应力与撞击速度关系,表明撞击应力并非由撞击速度单独决定,还与撞击位置有关,撞击速度、撞击应力及材料的流动性共同导致了波状焊接界面的形成,对其进行合理控制是改善焊接效果的关键.

为了研究制动机的制动性能,模拟制动或缓解时列车管及风缸压力变化曲线,采用MATLAB与C#开发平台的混合编程技术,能够实现输入车辆设备等参数,后台调用MATLAB进行压力计算并将结果反馈给C#,在软件界面中形象的以曲线形式实时显示出来.以列车管初充气模块为案例,开发了基于MATLAB与C#的初充气模型性能试验模拟系统.整套系统软件易于开发,操作方便,功能优良.

货车制动仿真系统采用电磁阀对列车管进行充排气,电磁阀的控制策略是准确模拟制动作用过程中气压变化的关键技术.提出一种基于模糊控制的制动回馈策略,以列车管理论计算模型为原型,以实际传感器测得的气压与理论值的气压差和气压差变化率为模糊输入,以控制电磁阀的开启时间,从而实现电磁阀对制动排气的实时准确控制.仿真结果表明,该策略控制列车制动过程中的气压变化更加精准.