Kyohei Nagao

Railway Technical Research Institute

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Yusuke Wakabayashi

East Japan Railway (Japan)

Takeshi MITSUMOJI

Railway Technical Research Institute

Takayuki Usuda

Railway Technical Research Institute

Tatsuya KOYAMA

Waseda University

Mitsuru Ikeda

Japan Advanced Institute of Science and Technology

Hiromasa Hirakawa

Railway Technical Research Institute

Shigeyuki KOBAYASHI

Railway Technical Research Institute

Arata MASUDA

Kyoto Institute of Technology

Tatsushi ISONO

Railway Technical Research Institute

Masaki Takahashi

Keio University

Cooperative Institutions

Railway Technical Research Institute

Keio University

Kyoto Institute of Technology

Osaka University

Tohoku University

Tokyo Institute of Technology

Waseda University

Nagoya University

PhoenixBio (Japan)

Kyorin University Hospital

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Three-dimensional Simulation of Catenary/Pantograph Dynamic Interaction

Quarterly Report of RTRI (2021)

Tatsuya KOYAMA Kyohei Nagao Mitsuru Ikeda

Simulation of Catenary/Pantograph dynamic interaction is used for understanding the dynamic behavior of overhead contact lines (OCL) and pantographs, and stability to supply electric power to a vehicle. The authors developed a new simulation tool using a three-dimensional model of OCL and a pantograph, which can calculate their full three-dimensional dynamic behavior. Each node in the OCL model has 6 degrees of freedom; this tool can evaluate contact quality between the OCL and a pantograph system even on curved sections. Furthermore, it can evaluate the expansion/contraction of OCL due to temperature change, which affects contact quality. This paper describes this simulation tool in detail, through the example of an analysis of the contact between contact lines and a pantograph from the results of a simulation of a pantograph passing a crossing section.

Pantograph

Catenary

Dynamic simulation

Contact force

10.2219/rtriqr.62.2_104

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Citations (3)

3204 Seismic Response of High-Speed-Moving Railway Vehicles Subjected to Long-period Earthquake Motions

The Proceedings of the Transportation and Logistics Conference (2014)

Hideki OHARA Akira SONE Arata MASUDA Kyohei Nagao Hayato Nakakoji

Recently, for the long-period ground motions by the Tokai earthquake, the Tonankai earthquake, et al., the safety of Tokaido-Shinkansen becomes a problem. In this paper, Using the analytical model of high-speed moving railway vehicles proposed by Shintani, et al., its dynamic behavior is studied by use of the artificial long-period ground motions and actual ground motion in lateral and vertical directions simultaneously. From the analytical results, some correlation effects between the lateral ground motion and vertical ground motion on the possibility of rollover of the vehicle are shown. Also, it is clear that the possibility of rollover of the vehicle is large for the long-period ground motions used in this study.

Rollover (web design)

Strong ground motion

10.1299/jsmetld.2014.23.107

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Citations (0)

The contact performance of prototype of multi-segment pantograph head

The Proceedings of the Transportation and Logistics Conference (2018)

Takayuki Usuda Takeshi MITSUMOJI Kyohei Nagao Yoshiki Kubota Yusuke Wakabayashi

In developing a pantograph of a high speed train, reducing aerodynamic noise of the pantograph is one of the most important subjects. For reducing this noise, suitable configuration of pantograph head, which has a smooth cross section profile, is investigated. However, the pantograph head with smooth cross section profile and conventional support system of contact strip sometimes wreak undesirable lift force characteristic. Authors are developing multi-segment pantograph head, which has a new support system without deterioration of lift force characteristic. This paper describes the validation result of this support system by model analysis and some test bench.

Pantograph

Lift (data mining)

Contact force

10.1299/jsmetld.2018.27.1310

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Parameter Identification of the Three-Dimensional Pantograph Simulation Model based on Vibration Test of the Actual Pantograph

The Proceedings of the Transportation and Logistics Conference (2018)

Kyohei Nagao Tatsuya KOYAMA Mitsuru Ikeda

Railway Technical Research Institute has been upgrading the pantograph/catenary simulator. As a part of the simulator improvement, a three-dimensional simulation model of pantograph was constructed. In this paper, the method of vibration test of actual pantograph to identify parameters of the pantograph model is introduced. First, the pantograph model is divided into two parts - panhead and the other. Then, vibration test for each part of actual pantograph is conducted, and acceleration and strain at multiple points on the pantograph are obtained to identify parameters of simulation model, for example, bending rigidity, torsion rigidity and so on. In the end, a simulation model of the entire pantograph is constructed and validated by comparing the result of vibration test of simulation model with that of the actual pantograph.

Pantograph

Catenary

10.1299/jsmetld.2018.27.1309

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Citations (2)

A study for practical application of aerodynamic noise reduction method of pantograph head and its support

The Proceedings of the Symposium on Environmental Engineering (2020)

Takeshi MITSUMOJI Takayuki Usuda Hiromasa Hirakawa Tatsushi ISONO Kyohei Nagao

Reduction in aerodynamic noise emitted from a pantograph is an important subject for reducing environmental impact and speed-up of high-speed trains. In the previous study, aerodynamic noise reduction method by smoothing pantograph head cross section, shifting pantograph head position, and applying porous material were proposed. In this study, a study for practical application of these aerodynamic noise reduction method is carried out and improved pantograph head and its support are developed. From a wind tunnel test result, it is clarified that these aerodynamic noise reduction method can reduce aerodynamic noise at 2.7dB compared to the currently used pantograph.

Pantograph

10.1299/jsmeenv.2020.30.106

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Citations (0)

Reduction of Aerodynamic Noise Emitted from Pantograph by Applying Multi-Segmented Smooth Profile Pantograph Head and Low Noise Pantograph Head Support

Lecture notes in mechanical engineering (2024)

Takeshi MITSUMOJI Takayuki Usuda Shigeyuki KOBAYASHI Kyohei Nagao Yuki Amano

Pantograph

10.1007/978-981-99-7852-6_19

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Citations (0)

Analysis of Pantograph and Catenary Behavior at Tunnel Entrance

Keisan Rikigaku Koenkai koen ronbunshu/Keisan Rikigaku Kouenkai kouen rombunshuu (2019)

Tatsuya KOYAMA Kyohei Nagao

In order to stably supply electric power to electric railcar, it is important to understand the interaction between overhead contact lines and pantographs. Lifting force of a pantograph is one of the important factor that influences the dynamic behavior of contact lines and a pantograph. The force has a characteristic that increases in proportion to the square of flow velocity around the pantograph. Since the flow velocity rapidly increases when a pantograph enters a tunnel, the flow velocity itself must be considered when the dynamic behavior is understood. Then, authors have developed a simulator, which can analyze the dynamic behavior when pantographs enter a tunnel, by one-way coupled analysis between numerical calculation result of air flow in the tunnel and pantograph/catenary simulation.

Pantograph

Catenary

Contact force

10.1299/jsmecmd.2019.32.225

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Citations (0)

Dynamic simulation of overhead contact lines and pantograph using three-dimensional MBD models

The Proceedings of the Dynamics & Design Conference (2020)

Tatsuya KOYAMA Kyohei Nagao Mitsuru Ikeda Takayuki Usuda

It is important to understand the dynamic behavior of overhead contact lines and pantographs to achieve stable power supply. For this purpose, simulation of catenary/pantograph dynamic interaction is often performed. However, since lumped-mass model of a pantograph has been used in the conventional simulation, the three-dimensional dynamic behavior of the pantograph is not able to be calculated. The authors developed a new simulation method using a threedimensional model of overhead contact lines and a pantograph. This paper shows contact analysis between contact lines and a pantograph, and a simulation result when a pantograph passes a crossing section.

Pantograph

Catenary

Overhead line

Contact force

Dynamic simulation

10.1299/jsmedmc.2020.507

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Citations (1)

Aerodynamic noise reduction by applying porous material to pantograph head support

The Proceedings of the Symposium on Environmental Engineering (2018)

Takeshi MITSUMOJI Kyohei Nagao Takayuki Usuda Yusuke Wakabayashi

Pantograph

10.1299/jsmeenv.2018.28.125

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Citations (0)

Transient wave propagation analysis of a pantograph- catenary system

Journal of Physics Conference Series (2016)

Kyohei Nagao Arata MASUDA

This paper proposes a systematic method to analyze the dynamic response of an overhead catenary with pantographs moving at constant speed. The overhead catenary is modeled as a onedimensional infinite-length string, which is periodically supported by hangers. On the other hand, the pantograph is a sub-structure moving at a constant speed, which is modeled as a lumped mass system contacting the catenary. In this study, the whole system is divided into elements in the manner of the transfer matrix method. Then, the relationship among traveling waves in every element is systematically obtained in the Laplace domain following the method of reverberation-ray matrix. Since the governing equation of the system changes periodically with time, the analysis of the temporal evolution of the system can be realized by repeating a single period analysis starting from the instant when the pantograph comes into a unit cell by means of the reverberation-ray matrix analysis followed by the inverse Laplace transform. When the pantograph reaches the opposite hanger, the whole elements are shifted backward, and the catenary response of the forehead element is used as the initial condition of the next period.

Catenary

Pantograph

Matrix (chemical analysis)

Transient (computer programming)

Constant (computer programming)

10.1088/1742-6596/744/1/012086

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Citations (1)