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Adaptive Fault Estimation for Dynamics of high speed train Based on Robust UKF Algorithm

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Journal of Harbin Institute of Technology(New Series) 2023年第1期30卷 61-72页

作者： Kexin Li Tiantian Liang School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian 116028China

This paper proposes an adaptive unscented Kalman filter algorithm(ARUKF)to implement fault estimation for the dynamics of high⁃speed train(HST)with measurement uncertainty and time⁃varying noise with unknown statistics.Firstly,regarding the actuator and sensor fault as the auxiliary variables of the dynamics of HST,an augmented system is established,and the fault estimation problem for dynamics of HST is formulated as the state estimation of the augmented system.Then,considering the measurement uncertainties,a robust lower bound is proposed to modify the update of the UKF to decrease the influence of measurement uncertainty on the filtering accuracy.Further,considering the unknown time⁃varying noise of the dynamics of HST,an adaptive UKF algorithm based on moving window is proposed to estimate the time⁃varying noise so that accurate concurrent actuator and sensor fault estimations of dynamics of HST is implemented.Finally,a five-car model of HST is given to show the effectiveness of this method.

关键词： high speed train Kalman filter adaptive algorithm robust algorithm unknown noise measurement uncertainty

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Simulation Analysis and Verifcation of Temperature and Stress of Wheel-Mounted Brake Disc of a high-speed train

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 331-339页

作者： Junsheng Qu Wenjing Wang Ziyu Dong Wei Shan School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Department of Locomotive&Vehicle China National Railway Group Co.LtdBeijing 100844China

During the braking process,a large amount of heat energy is generated at the friction surfaces between the brake disc and pads and rapidly dissipates into the disc volume.In this paper,a three-dimensional thermo-mechanical coupling model of high-speed wheel-mounted brake discs containing bolted joints and contact relationships is established.The direct coupling method is used to analyze the temperature and stress of the brake discs during an emergency braking event with an initial speed of 300 km/h.A full-scale bench test is also conducted to monitor the temperatures of the friction ring and bolted joints.The simulation result shows that the surface temperature of the friction ring reaches its peak value of 414°C after 102 s of braking,which agrees well with the bench test result.The maximum alternating thermal stress occurs in the bolt hole where the maximum circumferential compressive stress is−658 MPa and the maximum circumferential tensile stress is 134 MPa.During the braking process,the out-of-plane deformation of the middle part of the friction ring is larger than that of the edge,which increases the axial tensile load of the connecting bolt.This work provides support for the design of brake discs and connecting bolts.

关键词： high speed train Wheel-mounted brake disc Temperature feld Stress feld Thermo-mechanical coupling model Bolt

Numerical simulation and control of welding distortion for double floor structure of high speed train

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Acta Mechanica Sinica 2014年第6期30卷 849-859页

作者： Wen-Chao Dong Shan-Ping Lu Hao Lu Dian-Zhong Li Li-Jian Rong Yi-Yi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences CSR Qingdao Sifang Co. Ltd.

The welding heat source models and the plastic tension zone sizes of a typical weld joint involved in the double floor structure of high speed train under different welding parameters were calculated by a thermal-elastic-plastic FEM analysis based on SYSWELD code.Then,the welding distortion of floor structure was predicted using a linear elastic FEM and shrinkage method based on Weld Planner software.The effects of welding sequence,clamping configuration and reverse deformation on welding distortion of floor structure were examined numerically.The results indicate that the established elastic FEM model for floor structure is reliable for predicting the distribution of welding distortion in view of the good agreement between the calculated results and the measured distortion for real double floor structure.Compared with the welding sequence,the clamping configuration and the reverse deformation have a significant influence on the welding distortion of floor structure.In the case of30 mm reverse deformation,the maximum deformation can be reduced about 70%in comparison to an actual welding process.

关键词： Welding distortion Double floor welded structure high speed train Numerical simulation

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Detached-eddy simulation of flow around high-speed train on a bridge under cross winds

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Journal of Central South University 2016年第10期23卷 2735-2746页

作者：陈敬文高广军朱春丽 School of Traffic & Transportation Engineering Central South University Changsha 410075 China Key Laboratory of Traffic Safety on the Track of Ministry of Education (Central South University) Changsha 410075 China

In order to describe an investigation of the flow around high-speed train on a bridge under cross winds using detached-eddy simulation(DES), a 1/8th scale model of a three-car high-speed train and a typical bridge model are employed, Numerical wind tunnel technology based on computational fluid dynamics(CFD) is used, and the CFD models are set as stationary models. The Reynolds number of the flow, based on the inflow velocity and the height of the vehicle, is 1.9×10~6. The computations are conducted under three cases, train on the windward track on the bridge(WWC), train on the leeward track on the bridge(LWC) and train on the flat ground(FGC). Commercial software FLUENT is used and the mesh sensitivity research is carried out by three different grids: coarse, medium and fine. Results show that compared with FGC case, the side force coefficients of the head cars for the WWC and LWC cases increases by 14% and 29%, respectively; the coefficients of middle cars for the WWC and LWC increase by 32% and 10%, respectively; and that of the tail car increases by 45% for the WWC whereas decreases by 2% for the LWC case. The most notable thing is that the side force and the rolling moment of the head car are greater for the LWC, while the side force and the rolling moment of the middle car and the tail car are greater for the WWC. Comparing the velocity profiles at different locations, the flow is significantly influenced by the bridge-train system when the air is close to it. For the three cases(WWC, LWC and FGC), the pressure on the windward side of train is mostly positive while that of the leeward side is negative. The discrepancy of train's aerodynamic force is due to the different surface area of positive pressure and negative pressure zone. Many vortices are born on the leeward edge of the roofs. Theses vortices develop downstream, detach and dissipate into the wake region. The eddies develop irregularly, leading to a noticeably turbulent flow at leeward side of train.

关键词： detached-eddy simulation high speed train bridge cross wind flow structure train aerodynamics

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Genetic Algorithms with Application to Optimize high speed train ATO

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Genetic Algorithms with Application to Optimize High Speed T...

Robust and Adaptive Control of high speed train Systems

第一届交通运输工程国际学术会议

作者： YU Jin1, QIAN Qingquan2 , and HE Zhengyou 1Traction Power State Key Laboratory, Southwest Jiaotong University, Number 111 North Section1 Roundabout Road 2, Chengdu City, China P.O. BOX 610031 2Southwest Jiaotong University, Chengdu City, China. Academician of Chinese Academy of Engineering P.O. BOX 610031

In this paper, the distance-velocity curve of high speed train obtained with traction calculation is optimized by means of genetic algorithms, which safety, punctuality, comfort, energy cost of train running and stopping a train at target point have been considered. Accordingly, the optimal switch point of the train running condition （traction, inertia, braking and release etc.） can be got, which can be used for instructing high speed train automatic operation（ATO）. Simulation results show that this method is adequate and effective, and the expectation is achieved.

关键词： high speed train genetic algorithms optimization ATO

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Robust and Adaptive Control of High Speed Train Systems

A Glance of China high speed train

2010 Chinese Control and Decision Conference

作者： Qi Song~1,Y.D.Song~(1,2) 1 Center for Intelligent Systems and Renewable Energy,2 State Key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University,Beijing 100044

＜正＞This paper investigates the automatic control problem of high speed train systems under immeasurable aerodynamic drag.Robust and adaptive control algorithms are developed to ensure high precision tracking of train position and velocity.The control scheme does not rely on precise system parameters.Furthermore,there is no need for analytic estimation or experimental determination of resistance coefficients.It is also able to deal with various additional resistance due to uncertain operation railway conditions.The effectiveness of the proposed method is confirmed by theoretical analysis and numerical simulations.

关键词： Automatic train Operation Position and Velocity Tracking Robust and Adaptive Control high speed train Resistance

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校园英语 2017年第47期 255-255页

作者： Yaya Han Shuai Han CRRC Qingdao Sifang Co. Ltd.

China high speed rail has experienced rapid development in the recent decade with the longest operation mileage and largest number of high speed trains(HST) in the world. As the "Golden business card" of China’s diplomacy,China high speed train becomes the most popular transportation tool. This essay will start with an introduction of high speed rail.Before the conclusion, priority will be given to the social and environmental advantages that HST could bring.

关键词： high speed rail high speed train

Shear Flows in the Near-Turbulent Wake Region of high speed trains

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Fluid Dynamics & Materials Processing 2020年第6期16卷 53-66页

作者： Liang Ce Yongchen Pan China Academy of Railway Sciences Co. Ltd.Beijing100081China

Two flow cases for scaled high speed train models with different length are numerically analyzed in the framework of the improved delayed detachededdy simulation model.Specific attention is paid to the shear flows and related mechanisms in the near turbulent wake created by these moving models.In particular,a comparative analysis is made on the distributions of turbulent kinetic energy(TKE)and turbulence production(TP)in planes perpendicular to the streamwise direction.The numerical results suggest that,in the wake region very close to the tail,significant TKE and TP can be ascribed to the dynamic interaction between powerful eddies and strong shear,which explain why these quantities are sensitive to the shear strength.The shear flows are essentially governed by the boundary layers developing along the streamwise direction on the train surfaces,especially from the under-body region and the side walls.For other positions located in the downstream direction away from the tail,the interaction of vortices with the non-slip ground serves as a mechanism to promote transfer of energy from weak eddies to turbulence through the shear present in planes parallel to the ground.

关键词： high speed train near turbulent wake shear flow turbulent kinetic energy turbulence production

Influence of HIGP on Ground-reliance to Monopole Antennas

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Influence of HIGP on Ground-reliance to Monopole Antennas