• Study on Parallel Resonance Frequency of Traction Power Supply System for Train Groups Based on Modal Analysis Method
• Yang Jin
• 2024 Vol. 21 (5): 1-7. DOI:10.3969/j.issn.1673-4440.2024.05.001
• Abstract ( ) PDF (1332KB)( )
• As the transport volume of heavy-haul railways continuously increases, the problem of insufficient traffic capacity may be addressed by increasing the number of trains utilizing one and the same supply arm. However, when the number of trains is increased, the harmonic currents generated by multiple trains may be distributed at multiple locations of the traction network and may be superimposed, which causes serious accidents related to the parallel resonance of traction power supply systems. Therefore, it is necessary to study the frequency distribution of system harmonic resonance in the situation of multi-train operation. In this paper, the conductor multi-conductor step-down method is adopted to establish a simplified equivalent circuit model for the traction network.  Then, the modal analysis method is utilized to study the frequency changes of the parallel resonance of traction power supply systems in the situation of multi-train operation with power variation, so as to obtain the node participation information of harmonic resonance. The research results shows that when 6 trains operate in the traction network with power variation of 4~8 MW, there are 38~43 low-order harmonic waves and 116~118 high-order harmonic waves related to system harmonic resonance.
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• Optimization Method for Segmented Speed and Distance Monitoring Curve
• Zhang Guijuan, Bao Pengyu, Yu Xiaona, Wang Jianmin, Zhang Youbing, Zhang Zhenxing
• 2024 Vol. 21 (5): 8-13,19. DOI:10.3969/j.issn.1673-4440.2024.05.002
• Abstract ( ) PDF (1175KB)( )
• The existing segmented speed and distance monitoring curve is generated on the basis of the UIC544-1 standard, and by means of a braking deceleration model based on the vehicle braking performance (segmented braking speed and braking deceleration). As the impacts of external environment on vehicle braking performance are not fully considered, the resulting segmented speed and distance monitoring curve is not sufficiently accurate, which affects the safety and effectiveness of train operation. To solve the above problem, this paper studies the existing segmented speed and distance monitoring curve, and on this basis, proposes an optimization method. The proposed method combines multiple types of trackside data (such as gradient and adhesion data) with vehicle braking data, to generate more accurate segmented speed and distance monitoring curves, and ensure safer and more efficient train operation under various trackside conditions.
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• DCC-based Processing for Line Data Transmission, Reception and Utilization by Onboard ATP
• Chen Yang, Hao Yuxiang, Liu Yun
• 2024 Vol. 21 (5): 14-19. DOI:10.3969/j.issn.1673-4440.2024.05.003
• Abstract ( ) PDF (977KB)( )
• The line data is a key factor for the stable operation of trains. The traditional methods for line data update usually rely on stable network communication or plenty human resources. In some special scenarios, wireless network coverage is not available or network communication is not sufficiently reliable, which causes difficulties in line data update. To solve this problem, this paper studies a new method for line data update featuring data storage at the stations and data update at the sections. The proposed method enables timely line data update when wireless network coverage is not available. Thus, it improves the operation efficiency of trains, which has great importance for the stable operation of the railway transportation systems. 
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• Research on Hybrid Control Method for Safety Train Control System
• Hu Rui
• 2024 Vol. 21 (5): 20-26. DOI:10.3969/j.issn.1673-4440.2024.05.004
• Abstract ( ) PDF (1212KB)( )
• The Safety Train Control (STC) system is a type of core safety guarantee equipment that supports the interlocking functions related to the autonomous train control system. The control method for the signaling equipment in the STC system has been optimized and designed on the basis of the control method for the signaling system in existing mature interlocking systems. The advantages of relay control and fully electronic module control are combined, and different control methods are adopted for different types of signaling equipment and according to the type and scale of the stations. The control method for the signaling equipment in the STC system not only inherits the features of intelligentization, electronization and networkization of fully electronic control, but also reduces the use of signaling relays during the on-site installation of signaling equipment, which reduces the construction and retrofitting costs of station equipment to some extent. This paper first introduces the STC system, and elaborates on its system functions and interface characteristics. It then describes the control methods of such signaling equipment as signals, switches, and scattered relays in STC system. It also analyzes the mapping principles of the fully electronic modules and relays in signaling system control of STC system, and describes the prospects of the future promotion and application of signaling system control of STC system in view of its advantages.
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• Design and Implementation of IO Simulation System for DS6-100 Computer Interlocking
• Liu Xin
• 2024 Vol. 21 (5): 27-31. DOI:10.3969/j.issn.1673-4440.2024.05.005
• Abstract ( ) PDF (1403KB)( )
• This paper builds on the system structure of new self-developed DS6-100 computer interlocking (CI), and intends to solve the problems of needing to use a large number of IO modules and having difficulty in meeting the laboratory testing conditions during DS6-100 CI software testing. It describes the design and implementation of an IO simulation system for DS6-100 CI. The actual testing and application results show that the proposed system can meet the testing requirements of interlocking software, and expand testing coverage and improve testing efficiency.
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• Design and Implementation of Automatic Test Platform for Fully Electronic Interlocking
• Peng Dong, Cui Yan, Cao Yaxin
• 2024 Vol. 21 (5): 32-37,61. DOI:10.3969/j.issn.1673-4440.2024.05.006
• Abstract ( ) PDF (1129KB)( )
• To explore how to improve the coverage rate and accuracy of automatic tests for full electronic interlocking, this paper analyzes the functional test requirements and test scenarios of fully electronic interlocking. It also presents the design and implementation of an automatic test platform for fully electronic interlocking with the help of test script modularity and test library architecture. The proposed automatic test platform provides users with a test function library, which can effectively enhance the test efficiency and accuracy of full electronic interlocking.
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• Implementation Scheme for Replacing Manual Release Panel of QJK Equipment with CTC Equipment
• Pan Shenghao
• 2024 Vol. 21 (5): 38-41,74. DOI:10.3969/j.issn.1673-4440.2024.05.007
• Abstract ( ) PDF (835KB)( )
• At present, when the QJK equipment is used on normal speed railways provide the logical check function of section occupation, the block section release after section occupation loss is achieved with the manual release panel. Meanwhile, when the TCC equipment is used on dedicated passenger lines to achieve such logical check function, such block section release is achieved with the CTC equipment. This paper presents a scheme for replacing the manual release panel of the QJK equipment with the CTC equipment on normal speed railways. Based on any analysis of different types of stations, it proposes the replacement of the manual release panel of the QJK equipment by adding interfaces with the CTC equipment. The proposed scheme can improve the function expansibility of the manual release panel, and has obvious advantages in construction as well as operation and maintenance.
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• New Method of Level Crossing Protection Based on DX3 Level Crossing Signaling System
• Zhao Qianru
• 2024 Vol. 21 (5): 42-45,69. DOI:10.3969/j.issn.1673-4440.2024.05.008
• Abstract ( ) PDF (894KB)( )
• This paper proposes a new method of level crossing protection based on the DX3 level crossing signaling system. The requirement on the level crossing guard to confirm the completion of level crossing protection and the status of obstruction signals is added to the clearance conditions of train signals. Thus, the clearance conditions of train signals are controlled with the completion status of level crossing protection. When all the conditions are met, the proposed method can ensure traffic safety at the level crossing without delaying the clearance of train signals. Moreover, it greatly reduces traffic congestion pressure, improves the transport efficiency of railway trains and road vehicles, and upgrades the management level of railway level crossings. The proposed method is applicable to level crossings in stations and sections of single-track, double-track and multi-track lines with various types of traction interlocking and blocking systems.
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• Discussion on "Beidou+5G" Fusion Scheme for Train Positioning in Platform Area of High Speed Railways#br#
• Luo Yingxin, Ding Xun
• 2024 Vol. 21 (5): 46-52. DOI:10.3969/j.issn.1673-4440.2024.05.009
• Abstract ( ) PDF (1452KB)( )
• One current research focus is the train positioning technology that takes Beidou satellite navigation and positioning as the core and combines multiple positioning methods. To adress the current problem of obstruction of such structures as rain sheds, which affects satellite positioning accuracy, this paper discusses the feasibility of the technical scheme of "Beidou+5G" fusion for train positioning in the platform area of high speed railways. It also presents the accuracy verification of the 5G positioning technology in an experimental environment (simulated platform environment), and proposes a fusion algorithm for Beidou and 5G positioning data, which provides a new solution for improving train positioning accuracy.
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• Research and Design of Redundant Control Method for Double Radios Based on CTCS-N Train Control System
• Shan Feilong, Wang Jia
• 2024 Vol. 21 (5): 53-61. DOI:10.3969/j.issn.1673-4440.2024.05.010
• Abstract ( ) PDF (2335KB)( )
• For most existing CTCS train control systems, the single-radio and single-connection method is used to achieve wireless connection with the core network, which can neither effectively ensure the high reliability of wireless connection nor decrease the system failure rate. The design scheme proposed in this paper can not only achieve redundant control over double radios of the CTCS train control system, but also ensure that after the in-use radio fails, the onboard unit will automatically select the standby radio to re-establish a safe wireless connection with the wayside equipment. Thus, it ensures fast recovery of wireless communication between the onboard equipment and wayside equipment of the train control system. Moreover, the proposed design scheme allows multiple safe wireless connections between the in-use radio and multiple devices. Thus, it greatly improves the safety, reliability and fault tolerance of the CTCS train control system. Although there is some time delay in the switching process of double radios, this has very small impacts on the wireless communication between the onboard equipment and wayside equipment of the train control system. Therefore, redundant control over double radios will become a development trend of new train control systems in the future.
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• Research and Implementation of Train Approach Early Warning System Based on Secondary Radar
• Shi Yunfei
• 2024 Vol. 21 (5): 62-69. DOI:10.3969/j.issn.1673-4440.2024.05.011
• Abstract ( ) PDF (2865KB)( )
• During on-track railway construction operation, the construction personnel have to leave the track when a train approaches, to avoid collision between the train and the personnel and machinery. Therefore, accurate and reliable train approach early warning is critical for railway construction safety. This paper describes the application of the secondary radar technology to train approach early warning. It presents an analysis of the system application scenarios, a description of the working principles and communication scheme of the radar communication module, and proposes a design of the onboard and wayside devices. The test results show that the train approach early warning system based on secondary radar meets the requirements in railway construction operation.
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• Design and Implementation of Rail Network Diagram System for Regional Rail Transit
• Zhang Yewei
• 2024 Vol. 21 (5): 70-74. DOI:10.3969/j.issn.1673-4440.2024.05.012
• Abstract ( ) PDF (866KB)( )
• To meet the requirement of integrated collaborative transportation of regional rail transit, this paper proposes a rail network diagram system for regional rail transit. The information from various systems, such as the infrastructure status, passenger flow data, train operation situation, train equipment status and meteorological condition of the lines connected to the regional rail network, is split with stations and sections as nodes. Then, the split data is calculated and restructured, so that a node data model is generated with stations and sections as basic units, and all the data is displayed on the same base map. Thus, the proposed rail network diagram system provides comprehensive visual display of such information as the train distribution, real-time passenger flow, equipment status and safety early-warning of various lines in the regional rail network. It can facilitate manual decision-making and provide basic data for intelligent decision-making and commanding of the entire system.
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• Research on IPv6 Evolution in Railway Communication Networks of China Railway Jinan Group Co., Ltd.
• Gao Yuan, Zhang Lejun
• 2024 Vol. 21 (5): 75-80,121. DOI:10.3969/j.issn.1673-4440.2024.05.013
• Abstract ( ) PDF (1099KB)( )
• As a key component of railway transportation systems, the railway communication network plays a crucial role in this data age. As the next generation internet protocol, IPv6 has larger addressing space, better security, and higher performance. It has become an inevitable choice for the evolution of the railway communication networks, and provided broad prospects for the upgrade of railway communication networks and the development of smart railways. Taking the railway communication networks of China Railway Jinan Group Co, Ltd. (CR-Jinan) as the research object, this paper discusses the evolution method of IPv6 in the railway communication networks of CR-Jinan. Making use of the SRv6 technology, it also proposes a native IPv6 based SRv6 application plan for CR-Jinan, to meet the requirements of service applications in the future era of railway smart cloud network, such as jumping into the cloud. Thus, this paper provides a deployment plan and application suggestions for the development and construction of IPv6 based railway communication networks for CR-Jinan.
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• Residual Weighting Algorithm for Position Estimation Subway Construction Environment#br#
• Wang Lijun, Jiang Rui, Du Xiaowei, Li Dapeng
• 2024 Vol. 21 (5): 81-89,128. DOI:10.3969/j.issn.1673-4440.2024.05.014
• Abstract ( ) PDF (1405KB)( )
• For the underground indoor positioning in the subway construction environment, the Non-Line-Of-Sight (NLOS) error is an important influencing factor for the stability and accuracy of position estimation. Some existing techniques can eliminate NLOS errors to some extent, but these techniques often require priori information about NLOS channel conditions. This paper proposes a Developed residual weighting algorithm (D-rwgh) for position estimation based on the minimum residual principles. The proposed algorithm continuously rejects the base station with the largest error through the previous round of calculation, then conducts residual weighting for the position estimation corresponding to the number of base stations, and finally takes the weighting result as the final positioning result. The test results show the proposed algorithm does not need priori information about channel conditions, and has high positioning accuracy in the NLOS environment.
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• Research on Train Speed Measurement Method Based on Multiple-source Information Fusion Using Neural Network#br#
• Lu Haiting, Sun Chunyang, Wang Liangjun, Fu Baoming, Chen Linshan
• 2024 Vol. 21 (5): 90-95. DOI:10.3969/j.issn.1673-4440.2024.05.015
• Abstract ( ) PDF (913KB)( )
• The accuracy and reliability of autonomous speed measurement and positioning for subway trains are prerequisites for ensuring their driving safety and efficiency. This paper builds on the commonly used speed measurement methods for subway trains, and studies the selection of sensors and corresponding algorithms for multi-source data fusion. On this basis, it proposes an intelligent speed measurement method for subway trains using artificial neural networks and combining photoelectric sensors, Doppler radars and accelerometers. The proposed method fully utilizes the self-learning, adaptive, and non-linear capabilities of artificial neural networks. It uses the measured data from three types of sensors, i.e. photoelectric sensors, Doppler radars and accelerometers as its input. It utilizes RBF artificial neural networks for intelligent fusion and rapid optimization. Thus, the weights of the measured data from these sensors are adaptively adjusted to obtain the real-time speed values of subway trains, to achieve the goal of further improving the accuracy and reliability of train speed measurement.
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• Research on Cloud Platform Solution for Multi-node Network of Urban Rail Transit
• Liu Guodong, Li Jinlong
• 2024 Vol. 21 (5): 96-102,114. DOI:10.3969/j.issn.1673-4440.2024.05.016
• Abstract ( ) PDF (1082KB)( )
• Although a variety of cloud-edge collaboration solutions have been gradually implemented in the field of urban rail transit, most projects that have gone online still have such problems as low resource utilization and excess basic performance. To solve these problems, this paper proposes the optimized design idea of constructing a cloud platform for multi-node line network with a two-tier flat architecture consisting of a central layer and a line layer, to eliminate the division of work between the central layer and the line layer. Thus, the central layer takes charge of the dispatching and commanding of the line network, the collection of and service for subway data assets, as well as the basic support for intelligent applications at the network level. Meanwhile, the line layer breaks the barriers among various lines, builds edge nodes around transfer stations, provides basic resources for service systems of these lines, and meets the real-time service operation needs at the line side. The two-layer architecture design achieves the separation of network and line services. It also improves the real-time response capability of the cloud architecture, and greatly reduces the construction scale of the network data center.
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• Thoughts on Construction of Intelligent Operation and Maintenance Platform for Existing Line Signal System
• Yu Ke, Wang Chao
• 2024 Vol. 21 (5): 103-108. DOI:10.3969/j.issn.1673-4440.2024.05.017
• Abstract ( ) PDF (929KB)( )
• The signal system, as an important system to ensure the train operation of urban rail transit, has undergone rapid changes in its standards. At the same time, the types of signal equipment have become more diverse, which puts higher requirements on the operation and maintenance support of the signal system. The traditional maintenance methods can no longer meet the current operational and production needs. This paper provides a method to solve the maintenance difficulties of existing line signal systems by considering the construction of intelligent operation and maintenance platforms for existing line signal systems. 
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• Impacts of Accidental Faults of Train ATC Brake Relay and Countermeasures#br#
• Zhao Yong, Liu Lian, Chen Mida
• 2024 Vol. 21 (5): 109-114. DOI:10.3969/j.issn.1673-4440.2024.05.018
• Abstract ( ) PDF (2539KB)( )
• This paper build on the real scene of an event of train surpassing the fouling post during the subway operation period, and provides an in-depth analysis of some fault causes of trains not executing the braking command in the ATO mode. It also presents the study and implementation of relevant preventive measures, which can effectively improve the intervention efficiency of drivers and reduce the secondary impacts of faults.
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• Analysis of Frequency Use by LTE-M System in Shared Yard Section of Rail Transit Lines in Beijing#br#
• Li Ming
• 2024 Vol. 21 (5): 115-121. DOI:10.3969/j.issn.1673-4440.2024.05.019
• Abstract ( ) PDF (1018KB)( )
• All the new rail transit lines in Beijing have used the LTE-M system for comprehensive bearing of data and cluster services. In the case where the two lines use a shared yard section, frequency interference becomes inevitable. To ensure the overall reliability of the LTE-M system, this paper describes the service scenarios at the rolling stock depot and analyzes the frequency use of the LTE-M system in scenario of shared yard section. On this basis, it summarizes the principles of 1.8 G frequency use for shared yard section, which improves the reliability of vehicle-ground communication, and provides reference for the frequency planning of the LTE-M system for shared yard sections.
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• Research on Interface Scheme Between Depot Garage Door Control System and Signaling System for Urban Rail Transit Lines
• Li Yong
• 2024 Vol. 21 (5): 122-128. DOI:10.3969/j.issn.1673-4440.2024.05.020
• Abstract ( ) PDF (1040KB)( )
• For urban rail transit lines equipped with the Fully Automatic Operation (FAO) system, the doors of the train parking and maintenance garage in the depot service the purpose of isolating and blocking various fully automatic areas. As the garage doors need to be opened and closed when the trains enter and leave the garage, the control mode of the garage doors of urban rail transit lines can affect the safety and efficiency of train entrance to and exit from the garage. This paper first describes the principles of garage door control and protection for FAO lines. It then analyzes and compares different interface modes between the garage door control system and the signaling system. It finally proposes the interface mode suitable for FAO lines.
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