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A Loss-model-based Efficiency Optimization Control Method for Induction Traction System of High-speed Train under Emergency Self-propelled Mode
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作者 Yutong Zhu Yaohua Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期227-239,共13页
Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link v... Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results. 展开更多
关键词 Efficiency optimization Induction motor Loss model control Motor drives traction system
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Generalized autoencoder-based fault detection method for traction systems with performance degradation
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作者 Chao Cheng Wenyu Liu +1 位作者 Lu Di Shenquan Wang 《High-Speed Railway》 2024年第3期180-186,共7页
Fault diagnosis of traction systems is important for the safety operation of high-speed trains.Long-term operation of the trains will degrade the performance of systems,which decreases the fault detection accuracy.To ... Fault diagnosis of traction systems is important for the safety operation of high-speed trains.Long-term operation of the trains will degrade the performance of systems,which decreases the fault detection accuracy.To solve this problem,this paper proposes a fault detection method developed by a Generalized Autoencoder(GAE)for systems with performance degradation.The advantage of this method is that it can accurately detect faults when the traction system of high-speed trains is affected by performance degradation.Regardless of the probability distribution,it can handle any data,and the GAE has extremely high sensitivity in anomaly detection.Finally,the effectiveness of this method is verified through the Traction Drive Control System(TDCS)platform.At different performance degradation levels,our method’s experimental results are superior to traditional methods. 展开更多
关键词 Performance degradation Generalized autoencoder Fault detection traction control systems High-speed trains
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Electromagnetic Fields and Induced Voltages on Underground Pipeline in the Vicinity of AC Traction System 被引量:8
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作者 Bosko Milesevic Bozidar Filipovic-Grcic Tomislav Radosevic 《Journal of Energy and Power Engineering》 2014年第7期1333-1340,共8页
Various regulations, aimed at the protection of human beings and electrical equipment against possible adverse effects resulting from exposure to electromagnetic fields, have been issued in many countries. Most of the... Various regulations, aimed at the protection of human beings and electrical equipment against possible adverse effects resulting from exposure to electromagnetic fields, have been issued in many countries. Most of them are based on safety guidelines published by international expert groups. In this paper, electric and magnetic fields are calculated in the vicinity of 25 kV traction line supplying railway traction systems. Calculation results are compared to exposure limits specified by safety guidelines and regulations. Possible countermeasures for reduction of electromagnetic fields are proposed. Also, this paper presents a method for calculation of the induced voltages to an underground gas pipeline from a neighbouring 25 kV electric traction overhead line in case of short circuit. Calculations are performed with EMTP-ATP software. Possible countermeasures for reduction of induced voltages are proposed. 展开更多
关键词 Electric and magnetic fields electric traction system induced voltages underground gas pipeline.
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Machine learning for fault diagnosis of high-speed train traction systems: A review
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作者 Huan WANG Yan-Fu LI Jianliang REN 《Frontiers of Engineering Management》 CSCD 2024年第1期62-78,共17页
High-speed trains(HSTs)have the advantages of comfort,efficiency,and convenience and have gradually become the mainstream means of transportation.As the operating scale of HSTs continues to increase,ensuring their saf... High-speed trains(HSTs)have the advantages of comfort,efficiency,and convenience and have gradually become the mainstream means of transportation.As the operating scale of HSTs continues to increase,ensuring their safety and reliability has become more imperative.As the core component of HST,the reliability of the traction system has a substantially influence on the train.During the long-term operation of HSTs,the core components of the traction system will inevitably experience different degrees of performance degradation and cause various failures,thus threatening the running safety of the train.Therefore,performing fault monitoring and diagnosis on the traction system of the HST is necessary.In recent years,machine learning has been widely used in various pattern recognition tasks and has demonstrated an excellent performance in traction system fault diagnosis.Machine learning has made considerably advancements in traction system fault diagnosis;however,a comprehensive systematic review is still lacking in this field.This paper primarily aims to review the research and application of machine learning in the field of traction system fault diagnosis and assumes the future development blueprint.First,the structure and function of the HST traction system are briefly introduced.Then,the research and application of machine learning in traction system fault diagnosis are comprehensively and systematically reviewed.Finally,the challenges for accurate fault diagnosis under actual operating conditions are revealed,and the future research trends of machine learning in traction systems are discussed. 展开更多
关键词 high-speed train traction systems machine learning fault diagnosis
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Traction power systems for electrified railways:evolution,state of the art,and future trends 被引量:1
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作者 Haitao Hu Yunjiang Liu +4 位作者 Yong Li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao 《Railway Engineering Science》 EI 2024年第1期1-19,共19页
Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified ... Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy. 展开更多
关键词 Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system
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Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform
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作者 Lu Li Zeduan Zhang +5 位作者 Wang Cai Qikang Zhuang Guihong Bi Jian Deng Shilong Chen Xiaorui Kan 《Global Energy Interconnection》 EI CSCD 2024年第2期206-216,共11页
This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a disti... This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances. 展开更多
关键词 Through-type Cophase traction direct power supply system traction network Empirical wavelet transform(EWT) Longitudinal protection
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Theoretical and Experimental Study on Tension–Torsion Coupling Vibration for Time-Varying Elevator Traction System
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作者 Peng Xu Qifeng Peng +2 位作者 Fusong Jin Jianghong Xue Hong Yuan 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2023年第6期899-913,共15页
Elevators used in ultra-high buildings are prone to vibrating due to their ultra-long traction ropes,which significantly affects the comfort and safety of high-speed elevators.Therefore,vibration of the elevator has a... Elevators used in ultra-high buildings are prone to vibrating due to their ultra-long traction ropes,which significantly affects the comfort and safety of high-speed elevators.Therefore,vibration of the elevator has always been a topic of research interest.This paper presents a theoretical model for analyzing the tension–torsion coupling vibration of the time-varying elevator traction system.The constitutive relations with the tension–torsion coupling effect of the wire rope are reduced by analyzing the deformation mechanism of the spiral winding wire rope.Based on Hamilton’s principle,the equations of motion and corresponding boundary conditions for the tension–torsion coupling vibration of the elevator traction system are derived.The Galerkin method is employed to account for the influence of nonlinear boundary conditions and to transform the equations of motion into discrete ones with variable coefficients of time,which are solved using the Newmark-βmethod.The accuracy of the proposed model is justified by the good agreement between theoretical predictions and experimental results,following which,the influence of the operation status and structural parameters of the elevator traction system on its vibration performance is discussed in detail. 展开更多
关键词 Elevator traction system Wire rope Tension–torsion vibration TIME-VARYING
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Cooling System Design Optimization of an Enclosed PM Traction Motor for Subway Propulsion Systems 被引量:1
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作者 Longnv Li Nan Jia +2 位作者 Xizhe Wang Yiran Yun Gaojia Zhu 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第4期390-396,共7页
This paper presents the design optimization of a self-circulated ventilation system for an enclosed permanent magnet(PM)traction motor utilized in the propulsion systems for subway trains.In order to analyze accuratel... This paper presents the design optimization of a self-circulated ventilation system for an enclosed permanent magnet(PM)traction motor utilized in the propulsion systems for subway trains.In order to analyze accurately the machine's inherent cooling capacity when the train is running,the ambient airflow and the related heat transfer coefficient(HTC)are numerically investigated considering synchronously the bogie installation structure.The machine is preliminary cooled with air ducts set on the motor shell,and the fluidic-thermal field distributions with only the shell air duct cooling are numerically calculated.During simulations,the HTC obtained in the former steps is applied to the external surface of the machine to model the inherent cooling characteristic caused by the train movement.To reduce the temperature rise and thus guarantee the motor's working reliability,an internal self-circulated air cooling system is proposed according to the machine temperature distribution.The air enclosed in the end-caps is driven by the blades mounted on both sides of the rotor core and forms two air circuits to bring the excessive power losses generated in the heating components to cool regions.The fluid flow and temperature rise distributions of the cooling system's structural parameters are further improved by the Taguchi method in order to confirm the efficacy of the internal air cooling system. 展开更多
关键词 Permanent magnet(PM)traction motor Bogie installation structure Self-circulated ventilation system Taguchi method
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Pars plana vitrectomy with internal limiting membrane plugging assisted by autologous blood for optic disc pit associated with vitreomacular traction
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作者 Bin Chen Yan-Ting Li +2 位作者 Tian-Hong Wu Ya-Ping Yuan Yun-Feng Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第10期1957-1959,共3页
Dear Editor,We report a case of optic disc pit(ODP)associated with vitreomacular traction which has been successfully treated by a combined technique.We have obtained the written informed consent from the patient,and ... Dear Editor,We report a case of optic disc pit(ODP)associated with vitreomacular traction which has been successfully treated by a combined technique.We have obtained the written informed consent from the patient,and this case study is in accordance with the tenets of the Declaration of Helsinki. 展开更多
关键词 TECHNIQUE traction MACULAR
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Effect of endoscopic full-thickness resection assisted by distal serosal turnover with floss traction for gastric submucosal masses
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作者 Tian-Wen Liu Xiao-Feng Lin +3 位作者 Shu-Ting Wen Jing-Yi Xu Zhao-Li Fu Shu-Min Qin 《World Journal of Clinical Cases》 SCIE 2024年第16期2738-2744,共7页
BACKGROUND Complex and high-risk surgical complications pose pressing challenges in the clinical implementation and advancement of endoscopic full-thickness resection(EFTR).Successful perforation repair under endoscop... BACKGROUND Complex and high-risk surgical complications pose pressing challenges in the clinical implementation and advancement of endoscopic full-thickness resection(EFTR).Successful perforation repair under endoscopy,thereby avoiding surgical intervention and postoperative complications such as peritonitis,are pivotal for effective EFTR.AIM To investigate the effectiveness and safety of EFTR assisted by distal serosal inversion under floss traction in gastric submucosal tumors.METHODS A retrospective analysis of patients with gastric and duodenal submucosal tumors treated with EFTR assisted by the distal serosa inversion under dental floss traction from January 2023 to January 2024 was conducted.The total operation time,tumor dissection time,wound closure time,intraoperative bleeding volume,length of hospital stay and incidence of complications were analyzed.RESULTS There were 93 patients,aged 55.1±12.1 years.Complete tumor resection was achieved in all cases,resulting in a 100% success rate.The average total operation time was 67.4±27.0 min,with tumor dissection taking 43.6±20.4 min.Wound closure times varied,with gastric body closure time of 24.5±14.1 min and gastric fundus closure time of 16.6±8.7 min,showing a significant difference(P<0.05).Intraoperative blood loss was 2.3±4.0 mL,and average length of hospital stay was 5.7±1.9 d.There was no secondary perforation after suturing in all cases.The incidence of delayed bleeding was 2.2%,and the incidence of abdominal infection was 3.2%.No patient required other surgical intervention during and after the operation.CONCLUSION Distal serosal inversion under dental-floss-assisted EFTR significantly reduced wound closure time and intraoperative blood loss,making it a viable approach for gastric submucosal tumors. 展开更多
关键词 Endoscopic full-thickness resection Serosa inversion Dental floss traction Gastric submucosal tumor Auxiliary technology
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Laparoscopic Orchidopexy after 4 Weeks of Testicular Traction with Preservation of Blood Supply: A New Concept for the Treatment of Intra-Abdominal Cryptorchidism: Original Article
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作者 Ntsobe Tobie Eric Haijin Liu +5 位作者 Nyanit Bob Dorcas Wei Peng Feng Chen Ndikontar Raymond Kouna Tsala Irene Nadine Qian Liu 《Open Journal of Pediatrics》 2024年第2期205-217,共13页
Background: Testicular atrophy is recurrent after orchidopexy for intra-abdominal cryptorchidism due to damage to vessels. Fowlers-Stephens and Shehata methods proposed staged orchidopexy, but are still associated to ... Background: Testicular atrophy is recurrent after orchidopexy for intra-abdominal cryptorchidism due to damage to vessels. Fowlers-Stephens and Shehata methods proposed staged orchidopexy, but are still associated to a rate of atrophy greater than 10%. Purpose: We set out to present a new technique that preserves testicular vessels. Our study is aimed at investigating testicular vitality after surgery. Patients and Method: We reviewed files of boys who underwent orchidopexy for 2 years in our department. Those who have been operated for intra-abdominal cryptorchidism with the new technique and aged between 6 months and 14 years old were included in our study. We excluded boys who have been operated before 6 months and after 14 years old and those who did not respect their follow-up plane. Ultrasound (US) outcomes were used to measure testicular volumes and blood flow at each postoperative visit. The Sample population was divided into group A and group B representing testes that were followed respectively for 12 and 24 months. Results: 22 boys with 25 testes were included in our study;11 testes in group A and 14 testes in group B. In each group, we noted a significant difference of UDT volumes from the third month after surgery with respective P-values 0.05. There was no statistical difference between UDT and contra lateral testes volumes 12 months after surgery in group A and 24 months in group B with respective P-values of 0.07 and 0.72. All volume differential indexes were Conclusion: This method offers a new perspective in performing safe orchidopexy for intra abdominal undescended testes. 展开更多
关键词 LAPAROSCOPY Staged-Orchidopexy Testicar traction Testicular Atrophy
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Lasting Attraction
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作者 XIA YUANYUAN 《ChinAfrica》 2024年第4期22-24,共3页
High-level opening up and policies to attract foreign direct investment(FDI)were hot topics during the annual sessions of the National People’s Congress(NPC)and the Chinese People’s Political Consultative Conference... High-level opening up and policies to attract foreign direct investment(FDI)were hot topics during the annual sessions of the National People’s Congress(NPC)and the Chinese People’s Political Consultative Conference(CPPCC)National Committee,China’s key annual political meetings commonly known as Two Sessions. 展开更多
关键词 INVESTMENT traction POLITICAL
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Review and prospect of maintenance technology for traction system of high-speed train 被引量:3
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作者 Shaolong Xu Chunyang Chen +3 位作者 Zhenjun Lin Xiao Zhang Jisheng Dai Liangjie Liu 《Transportation Safety and Environment》 EI 2021年第3期196-215,共20页
In the past few decades,high-speed trains have witnessed tremendous and vigorous development with the appearance of the oil crisis and industrialization,which became a significant trend in the transportation industry ... In the past few decades,high-speed trains have witnessed tremendous and vigorous development with the appearance of the oil crisis and industrialization,which became a significant trend in the transportation industry the world over.With the increase of high-speed railway mileage,the amount of high-speed train has grown sharply,the service life of the trains has increased gradually and the components of the vehicle traction system have become worn and aged as a result.Therefore,advanced maintenance technology and its application are key factors to reduce maintenance cost,human resource input and ensure safe,stable and reliable operation of trains.This paper summarizes and discusses the development,application mode,maintenance management and maintenance technology of high-speed railways of the major countries in the world,especially discusses the condition-based maintenance and the key technology of the traction electrical system,and offers the prospect of research direction and the development of traction maintenance technology. 展开更多
关键词 high-speed railway traction system maintenance technology condition assessment life prediction condition-based maintenance Prognostic and health management(PHM)
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Health Status Assessment for New Urban Rail Vehicle Traction Systems Based on Cross Entropy and SVM
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作者 Zhenglong Zhou Yang Cheng +2 位作者 Shenggang Lv Kai Chen Weijing Du 《Chinese Journal of Electrical Engineering》 CSCD 2022年第2期108-120,共13页
A health status assessment method based on cross entropy and support vector machine(SVM)is proposed for the new urban rail vehicle traction systems.First,an index system for health assessment of the traction system is... A health status assessment method based on cross entropy and support vector machine(SVM)is proposed for the new urban rail vehicle traction systems.First,an index system for health assessment of the traction system is established,and combined weights of the index layer are obtained via cross entropy.Then,an SVM assessment model considering actual operating data and each status level of the traction system is established.Finally,the model is simulated in Matlab to obtain assessment results.The results indicate that the proposed method can provide the health status information of the traction system intuitively and complete the health status assessment of the traction system of the new urban rail vehicle effectively,by exploiting the traction system’s layered analysis model.The health status can be assessed accurately and reliably by adopting the cross entropy theory and SVM theory. 展开更多
关键词 New urban rail vehicle traction system cross entropy SVM health status assessment
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Algorithm for Calculating Torque Base in Vehicle Traction Control System 被引量:4
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作者 LI Hongzhi LI Liang +4 位作者 SONG Jian WU Kaihui QIAO Yanjuan LIU Xingchun XIA Yongguang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1130-1137,共8页
Existing research on the traction control system(TCS) mainly focuses on control methods, such as the PID control, fuzzy logic control, etc, aiming at achieving an ideal slip rate of the drive wheel over long control... Existing research on the traction control system(TCS) mainly focuses on control methods, such as the PID control, fuzzy logic control, etc, aiming at achieving an ideal slip rate of the drive wheel over long control periods. The initial output of the TCS (referred to as the torque base in this paper), which has a great impact on the driving performance of the vehicle in early cycles, remains to be investigated. In order to improve the control performance of the TCS in the first several cycles, an algorithm is proposed to determine the torque base. First, torque bases are calculated by two different methods, one based on states judgment and the other based on the vehicle dynamics. The confidence level of the torque base calculated based on the vehicle dynamics is also obtained. The final torque base is then determined based on the two torque bases and the confidence level. Hardware-in-the-loop(HIL) simulation and vehicle tests emulating sudden start on low friction roads have been conducted to verify the proposed algorithm. The control performance of a PID-controlled TCS with and without the proposed torque base algorithm is compared, showing that the proposed algorithm improves the performance of the TCS over the first several cycles and enhances about 5% vehicle speed by contrast. The proposed research provides a more proper initial value for TCS control, and improves the performance of the first several control cycles of the TCS. 展开更多
关键词 traction control system torque base torque control initial value
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New generation traction power supply system and its key technologies for electrified railways 被引量:6
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作者 Qunzhan Li 《Journal of Modern Transportation》 2015年第1期1-11,共11页
Unlike the traditional traction power supply system which enables the electrified railway traction sub- station to be connected to power grid in a way of phase rotation, a new generation traction power supply system w... Unlike the traditional traction power supply system which enables the electrified railway traction sub- station to be connected to power grid in a way of phase rotation, a new generation traction power supply system without phase splits is proposed in this paper. Three key techniques used in this system have been discussed. First, a combined co-phase traction power supply system is applied at traction substations for compensating negative sequence current and eliminating phase splits at exits of substations; design method and procedure for this system are presented. Second, a new bilateral traction power supply technology is proposed to eliminate the phase split at section post and reduce the influence of equalizing current on the power grid. Meanwhile, power factor should be adjusted to ensure a proper voltage level of the traction network. Third, a seg- mental power supply technology of traction network is used to divide the power supply arms into several segments, and the synchronous measurement and control technology is applied to diagnose faults and their locations quickly and accurately. Thus, the fault impact can be limited to a min- imum degree. In addition, the economy and reliability of the new generation traction power supply system are analyzed. 展开更多
关键词 New generation traction power supplysystem Combined co-phase power supply Bilateralpower supply Segmental power supply technology Synchronous measurement and control
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Wide speed range for traction motor in braking force of electric braking control system 被引量:2
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作者 Young-Choon Kim Moon-Taek Cho 《Journal of Central South University》 SCIE EI CAS 2014年第10期3837-3843,共7页
A vehicle stopping method using an electric brake until a traction motor is stopped is studied. At the moment of vehicle stop, electric brake is changed to control mode where torque is reduced at a low speed. Gradient... A vehicle stopping method using an electric brake until a traction motor is stopped is studied. At the moment of vehicle stop, electric brake is changed to control mode where torque is reduced at a low speed. Gradient is controlled by estimating the load torque of motor, thereby traction motor is not rotated after stop. In addition, coasting operation and brake test are performed from normal-opposite operation and start using a small-scale model comprising the inertial load equipment and the power converter. Further, traction motor is made to be equipped with a suspension torque. Pure electric braking that makes traction motor stop by an air brake at the time of stop is also implemented. Constant torque range and constant power range are expanded during braking so that braking force is secured with the electric brakes even in high speed region. Therefore, vehicle reduction effect can be expected by reducing parts related with an air brake which is not used frequently by using a pure electric brake in the M car in wide speed region. Further, maintenance of brake system can be reduced. Besides, ride comfort of passenger in the electric rail car, energy efficiency improvement, and noise reduction effect can be additionally expected. Further, an improved brake method that uses only an electric brake till motor stop is proposed by comparing those in the blending brake that uses an air brake while reducing brake torque at vehicle stop. 展开更多
关键词 wide speed range electric braking control traction motor
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Interference mechanism analysis and mitigation measures with railway signalling equipment from harmonics in the traction system 被引量:2
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作者 Zhiyu Li Shanghe Liu 《Transportation Safety and Environment》 EI 2020年第4期271-282,共12页
With the development of high-speed railway and heavy-haul rail transport in China,a large number of new types of electric locomotives and electric multiple units have been put into operation,improving the efficiency a... With the development of high-speed railway and heavy-haul rail transport in China,a large number of new types of electric locomotives and electric multiple units have been put into operation,improving the efficiency and equipment quality of railway transportation.However,harmonics emitted from the traction system and locomotives often interfere with the railway signalling equipment,which can lead to critical malfunction of the equipment.Based on field test data,this paper analyses the interference coupling mechanism and magnitude of traction harmonics to the signalling equipment using a three-element method of interference.It examines the three essential elements of electromagnetic interference,studies harmonic mitigation measures and proposes to solve the problem of inteference with signalling equipment by installing a passive high-pass filter in the coupling path.After comparing the effects of several types of filters using simulation tests,this paper verified the validity of the method and concluded that a second-order passive filter is the optimal solution for harmonic interference mitigation. 展开更多
关键词 heavy-haul railway traction harmonics INTERFERENCE signalling equipment
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A preventive opportunistic maintenance method for railway traction power supply system based on equipment reliability 被引量:3
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作者 Sheng Lin Nan Li +4 位作者 Ding Feng Xiaomin Guo Weiguo Pan Jun Wang Chao Yang 《Railway Engineering Science》 2020年第2期199-211,共13页
Conventional maintenance mode for the traction power supply system(TPSS)is to perform scheduled regular maintenance activities for power supply equipment,while such maintenance mode may result in undue maintenance tas... Conventional maintenance mode for the traction power supply system(TPSS)is to perform scheduled regular maintenance activities for power supply equipment,while such maintenance mode may result in undue maintenance tasks and low efficiency due to different degradation processes of different sorts of equipment.To address this problem,this paper introduces a preventive opportunistic maintenance(POM)method for TPSS based on equipment reliability.Firstly,a POM model is established by considering the equipment reliability degradation process based on Weibull distribution.Then,by considering the total power outage time in the planned operation cycle of TPSS as the optimization objective,the optimal maintenance scheme of TPSS is formulated by iterative method of maintenance strategies.The proposed method is verified by introducing practical maintenance strategies and fault record data of the traction transformer,circuit breaker and disconnector in an actual TPSS of a railway administration.Results show that the presented method can make full use of the existing fault data to develop a POM scheme for TPSS.It can improve maintenance efficiency and reduce power outage time,providing guidance to formulate scientific maintenance strategies for TPSS. 展开更多
关键词 Electrified railway Opportunistic maintenance interval Preventive opportunistic maintenance RELIABILITY traction power supply system Weibull distribution
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Power management in co-phase traction power supply system with super capacitor energy storage for electrified railways 被引量:4
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作者 Xiaohong Huang Qinyu Liao +2 位作者 Qunzhan Li Sida Tang Ke Sun 《Railway Engineering Science》 2020年第1期85-96,共12页
Increasing railway traffic and energy utilization issues prompt electrified railway systems to be more economical,efficient and sustainable.As regenerative braking energy in railway systems has huge potential for opti... Increasing railway traffic and energy utilization issues prompt electrified railway systems to be more economical,efficient and sustainable.As regenerative braking energy in railway systems has huge potential for optimized utilization,a lot of research has been focusing on how to use the energy efficiently and gain sustainable benefits.The energy storage system is an alternative because it not only deals with regenerative braking energy but also smooths drastic fluctuation of load power profile and optimizes energy management.In this work,we propose a co-phase traction power supply system with super capacitor(CSS_SC)for the purpose of realizing the function of energy management and power quality management in electrified railways.Besides,the coordinated control strategy is presented to match four working modes,including traction,regenerative braking,peak shaving and valley filling.A corresponding simulation model is built in MATLAB/Simulink to verify the feasibility of the proposed system under dynamic working conditions.The results demonstrate that CSS_SC is flexible to deal with four different working conditions and can realize energy saving within the allowable voltage unbalance of 0.008%in simulation in contrast to 1.3%of the standard limit.With such a control strategy,the performance of super capacitor is controlled to comply with efficiency and safety constraints.Finally,a case study demonstrates the improvement in power fluctuation with the valley-to-peak ratio reduced by 20.3%and the daily load factor increased by 17.9%. 展开更多
关键词 Electrified railway Co-phase traction POWER supply system Energy storage Peak SHAVING VALLEY FILLING POWER quality Super capacitor
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