무선통신기반 열차제어시스템에서의 운전시격 계산과 간격제어 성능개선을 위한 열차간격제어 알고리즘

오세찬(Oh, Seh-Chan),김경희(Kim, Kyung-Hee),이성훈(Lee Seong-Hoon),김자영(Kim, Ja-Young),전종화(Quan, Zhong-Hua) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.10

무선통신기반 열차제어시스템은 관할영역 내에 운행 중인 열차의 위치정보를 지상시스템에서 실시간으로 수신하고 다시 각각의 열차의 차상시스템에 새로운 이동권한을 제공함으로써 안전한 간격제어를 수행한다. 열차제어시스템의 성능은 최소 운전시격으로 평가되며 그것은 열차제어시스템의 간격제어 성능뿐만 아니라 운영특성 그리고 열차의 특성을 반영하여 계산된다. 본 논문은 무선통신기반 열차제어시스템의 운전시격 계산과 운전시격을 개선하기 위한 새로운 열차간격제어 알고 리즘을 제안한다. 제안된 운전시격 계산 방법은 열차제어시스템 간격제어 성능을 반영한 안전마진 추정을 통해 각각 역간 운전시격과 역 운전시격을 정의한다. 또한 제안된 열차간격제어 개선 알고리즘은 간격제어 개선을 위해 거리와 속도를 포함 하는 이동권한을 새롭게 정의하며 선행열차에서 필연적으로 발생하는 제동거리를 이용함으로써 열차의 운전시격을 향상시 킬 수 있다. 제안된 운전시격 계산방법을 한국형 무선통신기반 열차제어시스템의 간격제어 성능을 대상으로 시뮬레이션을 수행하며 개선된 열차간격제어 알고리즘과 비교분석 한다. 시뮬레이션 결과에 따르면 제안된 운전시격 계산방법은 향후 무 선통신기반 열차제어시스템의 성능 지표로 활용이 가능하며 제안된 간격제어 알고리즘은 기존의 무선통신기반 열차제어시 스템의 역 운전시격과 역간 운전시격을 개선할 수 있음을 확인한다. Radio based train control system performs train safe interval control by receiving in realtime the position information of trains driving in the control area of the wayside system and providing onboard system in each train with updated movement authority. The performance of the train control system is evaluated to calculate the minimum operation headway, which reflects the operation characteristics and the characteristics of the train as well as the interval control performance of the train control system. In this paper, we propose the operation headway calculation for radio based train control system and a new train interval control algorithm to improve the operation headway. The proposed headway calculation defines line headway and station headway by the estimation the safety margin distance reflecting the performance of the train control system. Furthermore the proposed Enhanced Train Interval Control(ETIC) algorithm defines a new movement authority including both distance and speed, and improves the train operation headway by using braking distance occurring inevitably in the preceding train. The proposed operation headway calculation is simulated with Korean Radio-based Train Control System(KRTCS) and the simulated result is compared to improved train interval control algorithm. According to the simulated results, the proposed operation headway calculation can be used as performance indicator for radio based train control system, and the improved train control algorithm can improve the line and station headway of the conventional radio based train control system.

무선통신기반 열차간격제어를 위한 전처리 기반 속도프로파일 계산 알고리즘

오세찬(Oh, Seh-Chan),김경희(Kim, Kyung-Hee),김민수(Kim, Min-Su) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.9

무선통신기반 열차제어시스템은 차상과 지상과의 양방향 무선통신을 기반으로 실시간 열차간격제어가 가능하므로 운전시격 단축 효과가 있으며 궤도회로를 사용하지 않기 때문에 설비투자를 절감 할 수 있다. 무선통신기반 열차제어시스템 에서 가장 중요한 부분인 자동열차방호(ATP: Automatic Train Protection)는 실시간 열차위치 추적을 기반으로 선행열차와 후행열차간의 안전한 간격제어를 수행한다. 본 논문은 도시철도용 무선통신기반 열차제어시스템의 열차간격제어를 위한 전 체적인 ATP 열차간격제어 알고리즘과 ATP의 처리속도 향상을 위해 전처리 기반 속도프로파일 계산 알고리즘을 제안한다. 제안된 속도프로파일 계산 알고리즘은 사전에 선로와 열차의 영구속도제한에 해당하는 프로파일을 미리 계산하여 가장제한 적인 속도프로파일로 활용한다. 만약 운행 중 특정 노선 구간에 임시속도제한이 발생하는 경우 미리 계산된 영구속도프로파 일에 임시속도제한을 반영하여 해당 구간의 속도프로파일을 업데이트함으로써 계산효율을 높일 수 있다. 제안된 속도프로파 일 계산 알고리즘의 성능을 평가하기 위해 시간복잡도 O-notation으로 분석하였으며 그 결과 기존에 비해 시간 복잡도를 개선 할 수 있음을 확인하였다. 또한 ATP 열차간격제어 검증을 위해 열차간격제어 시뮬레이터를 제작하였으며 실험결과를 통해 다양한 운영상황에서 안전한 열차간격제어가 이루어지고 있음을 확인하였다. Radio-based train control system has driving headway shortening effect by real-time train interval control using two-way radio communication between onboard and wayside systems, and reduces facility investment because it does not require any track-circuit. Automatic train protection(ATP), the most significant part of the radio-based train control system, makes sure a safe distance between preceding and following trains, based on real-time train location tracing. In this paper, we propose the overall ATP train interval control algorithm to control the safe interval between trains, and preprocessing-based speed profile calculation algorithm to improve the processing speed of the ATP. The proposed speed profile calculation algorithm calculates the permanent speed limit for track and train in advance and uses as the most restrictive speed profile. If the temporary speed limit is generated for a particular track section, it reflects the temporary speed limit to pre-calculated speed profile and improves calculation performance by updating the speed profile for the corresponding track section. To evaluate the performance of the proposed speed profile calculation algorithm, we analyze the proposed algorithm with O-notation and we can find that it is possible to improve the time complexity than the existing one. To verify the proposed ATP train interval control algorithm, we build the train interval control simulator. The experimental results show the safe train interval control is carried out in a variety of operating conditions.

A Feasibility Study on TETRA System Application for Train Control Systems

Tsogtbayar, Chinzorig,Kang, Hyoungseok,Lee, Jongwoo,Boldbaatar, Tsevelsuren The Korean Society for Railway 2016 International Journal of Railway Vol.9 No.2

TETRA communication system is very versatile system which can transmit voice + data and packet data optimized. Direct mode operation permits to connect between mobiles when mobile stain is out of coverage of networks. It can be more secure communication channel for railway signaling systems. Railway signaling systems use many of wayside signal equipment, which require many maintenance efforts and budget. Many railway authorities want to reduce and replace the wayside equipment. Radio based signaling systems are one of candidate for replacing the conventional signaling systems. The radio based signaling systems can replace track circuit and wayside signal. The radio systems permit to connect between control centers and trains. The radio systems have to ensure high quality of the connectivity more or equal to the existed track circuits. We studied the application of TETRA systems for railway radio systems for bridging between train control centers and trains. We provide an operation scenario for radio based train control system to ensure the safety require to the existed trains control system and satisfied the existed operational availability. We showed the data transmission speed, maximum bit error rate, and data coding for the radio-based signal system using TETRA systems.

A Feasibility Study on TETRA System Application for Train Control Systems

Chinzorig Tsogtbayar,Hyoungseok Kang,Jongwoo Lee,Tsevelsuren Boldbaatar 한국철도학회 2016 International Journal of Railway Vol.9 No.2

TETRA communication system is very versatile system which can transmit voice + data and packet data optimized. Direct mode operation permits to connect between mobiles when mobile stain is out of coverage of networks. It can be more secure communication channel for railway signaling systems. Railway signaling systems use many of wayside signal equipment, which require many maintenance efforts and budget. Many railway authorities want to reduce and replace the wayside equipment. Radio based signaling systems are one of candidate for replacing the conventional signaling systems. The radio based signaling systems can replace track circuit and wayside signal. The radio systems permit to connect between control centers and trains. The radio systems have to ensure high quality of the connectivity more or equal to the existed track circuits. We studied the application of TETRA systems for railway radio systems for bridging between train control centers and trains. We provide an operation scenario for radio based train control system to ensure the safety require to the existed trains control system and satisfied the existed operational availability. We showed the data transmission speed, maximum bit error rate, and data coding for the radio-based signal system using TETRA systems.

열차 제어 시스템을 위한 자동 진단 및 실시간 모니터링 소프트웨어

서동진(Dong-Jin Suh),박재근(Jaegeun Park),원유창(Yuchang Won),은용순(Yongsoon Eun) 제어로봇시스템학회 2021 제어·로봇·시스템학회 논문지 Vol.27 No.3

Train control systems consist of supervisory controller, network, and multiple trains. Actual trains are controlled and supervised by computer based signals, which put this system in the paradigm of CPS (Cyber-Physical Systems). Recent trends in train control systems are adopting wireless communication protocols to improve operational efficiency. While efficiency is improved by overcoming legacy fixed block based operation, wireless communication channels open new surfaces for external attack and malfunction. Actual attacks on CPS indeed have been materialized in trains, and as a result, attention from academia and industry for resiliency for train control systems are increasing. This manuscript overviews the trend and latest effort to this regard and introduces status of train control software that enhances the aspect of automatic diagnosis and real-time monitoring features.

무선통신 열차제어시스템 선로 용량에 대한 정보 전송 시간의 영향 분석

김정태(Jungtai Kim) 대한전자공학회 2017 전자공학회논문지 Vol.54 No.10

무선통신기반 열차제어시스템을 위한 개선된 ATP 핸드오버

오세찬,김영주 한국산학기술학회 2022 한국산학기술학회논문지 Vol.23 No.12

All trains in a communication-based train control(CBTC) system report their position to a wayside ATP in the jurisdictional area and travel when the wayside ATP provides movement authority, which is a limit of the distance to travel. For a train to travel between two or more jurisdictions, handover is required. Handover is a complex process of exchanging control information between the train and ground ATP. This study analyzes the problems of the handover algorithm of the Korean Radio-based Train Control System (KRTCS) and proposes a handover algorithm that supports various operation schedules by handover revocation or handover authority transfer according to the traveling direction and position of a train. In addition, a handover message structure for the Korean Railway Standards(KRS SG 0069) of KRTCS is proposed to support the new handover algorithm. In order to analyze the performance of the proposed handover algorithm, a zone for a train model and route was defined. Through simulation, the handover suggested in the existing standard and various operation schedules were compared and analyzed. The simulation results confirmed that the proposed handover algorithm enables stable handover even in situations such as a direction change at all handover sections. 무선통신기반 열차제어시스템의 모든 열차는 관할영역의 지상 ATP에 자신의 위치를 보고하고 지상 ATP로부터주행 가능한 거리의 한계인 이동권한을 받아 주행한다. 열차가 두 개 이상의 관할영역을 주행하기 위해서는 열차와 지상ATP간 복잡한 제어정보 교환 절차인 핸드오버가 필요하다. 본 논문은 한국형 무선통신기반 열차제어시스템의 핸드오버알고리즘의 문제점을 분석하여 이를 보완할 수 있는 핸드오버 알고리즘을 제시한다. 제안된 핸드오버 알고리즘은 열차의주행 방향과 위치에 따라 핸드오버 취소 또는 핸드오버 권한 이전을 수행함으로써 다양한 운행 스케줄을 지원한다. 또한새로운 핸드오버 알고리즘을 지원하도록 한국형 무선통신기반 열차제어시스템의 한국철도표준규격(KRS SG 0069)의핸드오버 메시지 구조를 새롭게 제시한다. 제안된 핸드오버 알고리즘의 성능분석을 위해 열차 모델과 노선에 대한 zone 을 정의하고 시뮬레이션을 통해 기존 표준규격에서 제시한 기존 핸드오버와 다양한 운행 스케줄을 대상으로 비교분석한다. 시뮬레이션 결과를 통해 제안된 핸드오버 알고리즘은 모든 핸드오버 영역에서의 방향 전환 등의 상황에도 안정적인 핸드오버가 가능함을 확인할 수 있다.

The Influence of Noise Environment upon Voice and Data Transmission in the RF-CBTC System

Kim, Min-Seok,Lee, Sang-Hyeok,Lee, Jong-Woo The Korean Society for Railway 2010 International Journal of Railway Vol.3 No.2

The RF-CBTC (Radio Frequency-Communication Based Train Control) System is a communication system in railroad systems. The communication method of RF-CBTC system is the wireless between the wayside device and on-board device. The wayside device collects its location and speed from each train and transmits the distance from the forwarding train to the speed-limit position to it. The on-board device controlling device controls the speed optimum for the train. In the case of the RF-CBTC system used in Korea, transmission frequency is 2.4 [GHz]. It is the range of ISM(Industrial Scientific and Medical equipment) band and transmission of voice and data is performed by CDMA (Code Division Multiple Access) method. So noises are made in the AWGN (Additive White Gaussian Noise) and fading environment. Currently, the SNR (Signal to Noise Ratio) is about 20 [dB], so due to bit errors made by noises, transmission of reliable information to the train is not easy. Also, in the case that two tracks are put to a single direction, it is needed that two trains transmit reliable voice and data to a wayside device. But, by noises, it is not easy that just a train transmits reliable information. In this paper, we estimated the BER (Bit Error Rate) related to the SNR of voice and data transmission in the environment such as AWGN and fading from the RF-CBTC system using the CDMA method. Also, we supposed the SNR which is required to meet the BER standard for voice and data transmission. By increasing the processing gain that is a ratio of chip transmission to voice and data transmission, we made possible voice and data transmission from maximally two trains to a wayside device, and demonstrated it by using Matlab program.

CBTC 무선기반열차제어 시스템에서 RFID를 이용한 실시간 열차 현재위치 구현에 관한 연구

강구안(Ku-An Kang),김대일(Dae-Il Kim),김장열(Jang-Yeol Kim),김윤수(Yoon-Soo Kim) 한국철도학회 2013 한국철도학회 학술발표대회논문집 Vol.2013 No.11

부산김해경전철은 한국에서 처음으로 계통된 CBTC(Communication Based Train Control) 기반 궤도 방식의 무인경전철이다. CBTC 방식의 무인경전철이 운영되기 위해서는 열차의 현재위치 계산은 필수적이다. 현재 위치를 실시간으로 계산이 되어야 열차의 속도, 안정된 위치에서의 비상정지, PMA에 열차의 진입 허가 금지 등의 제어가 가능하기 때문이다. 현재 무선열차제어에서 현재위치를 계산하는 방식은 두 가지 방법이 있다. 첫 번째는 열차의 절대 위치를 계산하기 위하여 트랜스폰드(RFID Tag)를 사용하여 열차의 절대 위치를 데이터베이스에서 불러오고 또한 미세거리 차이를 보정하는 기능을 한다. Tag와 Tag사이의 상대 거리는 타코미터라는 장비를 두 개 사용하여 바퀴회전 수로 거리값을 비교하여 산출한다. 본 논문에서는 RFID 리더와 Tag만을 사용하여 이동하는 열차의 진행방향을 결정하는 방법, 결정된 방향으로 산출된 절대위치에서 Tag와 Tag 사이의 상대위치를 속도와 시간을 사용하여 상대 위치를 계산하는 방법, 상대위치에서 차량의 역전기와 마스콘의 모드를 활동하여 상대위치의 거리를 가감하는 방법, 절대 위치를 저장한 데이터베이스의 개략적인 구조를 제안하고자 한다. BGLRT(Busan-Gimhae Light Rail Train) based railroad in Korea is applied first time used by CBTC method which is driverless train. The most important in driverless trains is how go get the real time current position for running trains. These methods which are getting the current position are using for two methods. The first is using for RFID Tag to get the current position that is get the fixed position at each Tag. The RFID reader read the tag and then gets the current position from Database in VOBC at each trains. Second method is using Tachometer to gets the relative position between tag and tag which relative distance is counting the Tachometer’s rolling. This thesis is supposed to: how to define running train’s direction used by tag ID in database. And how to get the relative position between tag and tag that only used by speed and time. And others are how to increment/decrement the relative distance between tag and tag form fixed position about running trains.

The Influence of Noise Environment upon Voice and Data Transmission in the RF-CBTC System

Minseok Kim,Sanghyeok Lee,Jongwoo Lee 한국철도학회 2010 International Journal of Railway Vol.3 No.2