Lines In Japan Research Articles

Development of Current Limiting Arcing Horn (MOV type arrester with external gap) for 22 kV power distribution line

In Japan, EGLA has been increasing since ZnO was developed. We developed Current Limiting Arcing Horn (CLAH) for 22kV power distribution line which was one of the EGLA. A lot of composite type lightning protection devices including CLAH are adopted for 6.6kV power line in Japan. This CLAH is the first lightning protection device, which used MOV, on 22kV distribution line in Japan. CLAH is better than arrester and arcing horn in interrupting the follow-current, re-transmission and other abilities. This product will contribute to be the decreasing outages for 22kV distribution line.

Environmental risk assessment and field performance of rose (Rosa×hybrida) genetically modified for delphinidin production

The release of genetically modified plants into the environment can only occur after permission is obtained from the relevant regulatory authorities. This permission will only be obtained after extensive risk assessment shows comparable risk of impact to the environment and biodiversity as compared to non-transgenic host plants. Two transgenic rose (Rosa×hybrida) lines, whose flowers were modified to a bluer colour as a result of accumulation of delphinidin-based anthocyanins, have been trialed in greenhouses and the field in both Japan and Australia. Flower colour modification was due to expression of genes of a viola flavonoid 3′,5′-hydroxylase and a torenia anthocyanin 5-acyltransferase. In all trials it was shown that the performance of the two transgenic lines, as measured by their growth characters, was comparable to the host untransformed variety. Biological assay showed that the transgenic lines did not produce allelopathic compounds. In Japan, seeds from wild rose species that had grown in close proximity to the transgenic roses did not carry either a Rosa×hybrida specific marker gene or the transgenes. In hybridization experiments using transgenic rose pollen and wild rose female parents, the transgenes were not detected in the seed obtained, though there was a low frequency of seed set. The transgene was also not transmitted when Rosa×hybrida cultivars were used as females. In in situ hybridization analysis transgene transcripts were only detected in the epidermal cells in the petals of the transgenic roses. In combination, the breeding and in situ analysis results show that the transgenic roses contain the transgene only in the L1 layer cells and not in the L2 layer cells that generate reproductive cells. General release permissions have been granted for both transgenic lines in Japan and one is now commercially produced.

DISPLAY DEMAND SPURS INVESTMENT

FUJIFILM AND KURARAY, two producers of key materials used in the manufacture of liquidcrystal displays (LCDs), will invest hundreds of millions of dollars in Japan in new production capacity for polarizer films. The driver behind both projects is strong global demand for flat-display television sets. Fujifilm is spending a total of $460 million on new production lines for making triacetate cellulose films. Kuraray will spend $57 million to expand production of polyvinyl alcohol-based film. Kuraray has a near-monopoly in the market for the polyvinyl alcohol films that are the base films in LCD polarizers, which sharpen TV displays. The company will add 20 million m 2 of capacity at a plant in Ehime, Japan. With a market share in excess of 80%, Fujifilm dominates the market for triacetate cellulose films used as a protective layer on the polarizers. The company is adding three production lines in Japan for films that will be used to make ...

Lightning surge characteristics of an actual distribution line and validation of a distribution line model for lightning overvoltage studies

AbstractFor distribution lines in Japan, protection measures against lightning‐induced overvoltages have been taken and can be considered almost complete. The focus of lightning protection measures has moved to overvoltages due to direct lightning strokes. Studies of such overvoltages require simulations using the EMTP (Electro‐Magnetic Transients Program), and components of a distribution line must be modeled appropriately in the EMTP simulation environment. The authors have proposed an EMTP model of a distribution line in a separate paper. This paper consists of two parts. The first part presents surge characteristics of a distribution line obtained by measurement using an actual‐scale test distribution line. In particular, the result reveals noteworthy characteristics of the surge impedance of a reinforced concrete pole and the wavefront‐time dependence of insulator voltages. The second part presents a validation of the distribution line model previously proposed by the authors. The validation shows that the distribution line model accurately reproduces the measured voltage and current waveforms for various wavefront times of the injected currents. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(1): 1–10, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.21002

雷サージ解析のための引込線および屋内配線のモデリング

As the information society progresses, a variety of electronic appliances have come into wide use in common houses. If a lightning stroke causes faults or incorrect operations of these electronic appliances, a social economic loss is considered to be large. For this reason, the focus of lightning protection measures for distribution lines in Japan has expanded to include the low-voltage side of the distribution line in addition to the high-voltage side. In order to calculate lightning overvoltages at the low-voltage side, the surge characteristics of service-drop wires and interior-wiring cables have to be modeled accurately.First, this paper describes test results of the surge characteristics of service-drop wires and interior-wiring cables. The modal surge impedances and the propagation velocities of various service-drop wires and interior-wiring cables are obtained by the test. Based on the test results obtained, this paper proposes a modeling methodology of these wires and cables for accurate EMTP (Electro-Magnetic Transients Program) lightning overvoltage simulations. The proposed model is validated by comparing EMTP simulation results with field test results.

The Influence of Wheel and Track Parameters on Rolling Noise

Railway noise from conventional meter-gauge lines in Japan mainly consists of rolling noise and traction-motor fan noise. Rolling noise is generated by vertical vibration of the wheel and rail, which is induced by relative displacement between the two due to the roughness on their surfaces. Through field tests, it was found that the excitation of rolling noise is determined by both the wheel/rail roughness and the vibratory behaviour of rolling stock and tracks. A theoretical model for rolling noise (such as TWINS) was then applied to Japanese railways, with the predictions showing a close correlation to the measured values. In terms of noise spectra, the rail was found to contribute more to rolling noise than the wheel in much of the frequency range. An attempt to estimate the effect of wheel and track parameters on rolling noise was also made using the TWINS model. The stiffness of the rail pad was found to affect the balance between the rail and sleeper components of noise, and additional damping for the rail was deemed effective in reducing the rail component of noise.

Characterization of Large Lithium Ion Battery and Its Application to Railcar

The running test of railcar was examined using large lithium ion battery in the local line in Japan. 90 kWh of Mn type lithium ion battery was used. The relation between running time and voltage, current and integrating watt was investigated in detail. The railcar was run when the lithium ion battery module was discharged between 660 V and 480 V. The use of lithium ion battery had little voltage changes and enabled the smooth running compared with contact-wire type railcar. On one charge, it was also found from the running test that the railcar could run for about 40 km and the mileage improved 9 %. The running performance of lithium ion battery type railcar was equivalent to the contact-wire type railcar. It was found that the railcar powered by lithium ion battery was effective for the replace of diesel type railcar in the local line.

Study on Transmission-Line Arresters for Tower With High Footing Resistance

The countermeasure against lightning faults is one of the most decisive factors in designing a transmission line in a high grounding resistance area. The higher the footing resistance is, the higher the resulting lightning surge voltage borne by the insulator string is. But it is practically not so easy to decrease the tower footing resistance. Lightning arresters for the transmission line have been developed and are already in successful service. However, the application effect of line arresters to the tower of high footing resistance has not been studied yet. This paper describes the results of computer calculation regarding the application effect of transmission-line arresters assuming typical parameters of the 77-kV line in Japan. As a result, the line arresters can effectively prevent the lightning faults in an area of high footing resistance.

Measurement of residual stresses in rails by neutron diffraction

Rolling contact fatigue damage is accumulated in rails during the repeated passage of trains over the rails, and an incipient crack may initiate due to the rolling contact fatigue. Rail failures can occur due to crack growth in the rails. In order to prevent such rail failures, the estimation of the behavior of internal rail cracks is required on the basis of an exact engineering analysis model as well as a method to detect rail defects before the crack grows to critical size. It is expected that the residual stress distribution in a rail has a significant influence on the growth rate of the crack. The purposes of this study are to measure the residual stress distribution in rails utilizing the neutron strain measurement. The test samples were taken from rails used in a service line in Japan for about six years (222 million gross tons). The neutron measurement was conducted using the Residual Stress Analyzer (RESA) at the Japan Atomic Energy Agency (JAEA). This report presents the results of the neutron strain measurements on a longitudinal-cut slice of a rail.

Effect of rail grinding on rolling contact fatigue in railway rail used in conventional line in Japan

Effect of rail grinding on the rolling contact fatigue in conventional railway rail used in commuter line was investigated by means of metallographic observation, crystal orientation analysis by axis density measurement with X-ray diffraction, and EBSP analysis. Grinding was carried out twice to obtain a series of test rails with different grinding history. The metallographic observation confirmed that the rail grinding directly removes the plastic flow layer at the running surface of rail. Furthermore, examinations on the variation of the 1 1 1 axis density in the direction of depth and EBSP orientation map of the test rails show that the rail grinding seems not only to remove the fatigue of influence caused by the rolling contact with wheel and accumulated at the surface but to moderate them even at the inner position below the running surface although the action of the grinding does not directly attack at the area.

Application of Neutron Diffraction Technique to Industrial Materials

As an important industrial problem, the rolling contact fatigue damage is accumulated in rails during the repeated passage of trains over the rails, and rail failures may occur from the cracks grown in the rails. In order to prevent such rail failures, the estimation of the behavior of internal rail cracks is required based on the exact engineering analysis model as well as conducting rail test to search rail defects. The purposes of this paper are to apply the neutron stress measurement to rails, and to obtain residual stress state in the rails for the above purpose. The rail samples used were those that have been used in service line in Japan for about six years (222 million gross tons). The neutron measurement was conducted using the Residual Stress Analyzer (RESA) of the Japan Atomic Energy Agency (JAEA). The present measurement of stresses in rails by the neutron diffraction method was the first attempt in Japan.

Structure of an Independent-wheel-system Bogie with a DDM and its Performance at High Speed

We have developed a new-concept bogie for gauge-changeable trains that is applicable to both standard gauge 1,435-mm line and meter gauge 1,067-mm line. The bogie must therefore feature good running stability at high speeds on standard gauge lines as well as high running performance on the curves of meter gauge line. It adopts a direct-drive motor system to enable the motor to be mounted directly to the wheels, an independent wheel system and a wheel-set steering system. The independent wheel system provides the bogie with good running stability at high speeds with a short wheelbase. We tested the model on our rolling stock test machine, and confirmed that no stability problems occurred at speeds of up to 500 km/h. We also conducted high-speed performance testing at the Transportation Technology Center Inc. in Pueblo, Colorado, USA, and on the Sanyo Shinkansen line in Japan at speeds of over 200 km/h.

実規模配電線雷サージ特性の測定と配電線解析モデルの検証

For distribution lines in Japan, protection measures against lightning induced overvoltages have been taken and can be considered almost complete. The focus of lightning protection measures has moved to overvoltages due to direct lightning strokes. Studies of such overvoltages require simulations using the EMTP (Electro-Magnetic Transients Program), and components of a distribution line must be modeled appropriately in the EMTP simulation environment. The authors have proposed an EMTP model of a distribution line in a separate paper.This paper consists of two parts. The first part presents surge characteristics of a distribution line obtained by measurement using an actual-scale test distribution line. Especially, the result reveals noteworthy characteristics of the surge impedance of a reinforced concrete pole and the wavefront-time dependence of insulator voltages. The second part presents validation of the distribution line model previously proposed by the authors. The validation shows that the distribution line model accurately reproduces the measured voltage and current waveforms for various wavefront times of injected currents.

Technical trends of high voltage and large capacity underground power cables

AbstractA 275 kV cross‐linked polyethylene (XLPE) cable with a large size conductor is mainly used for large‐capacity underground transmission lines in Japan. Furthermore, 275 kV gas insulated transmission line (GIL), which has a larger transmission capacity than 275 kV XLPE cable, has been developed and is in operation. The achievements regarding high voltage, large capacity underground transmission lines applied by the Chubu Electric Power Company will be introduced. In addition to these technologies, recent technical trends such as Rubber Blocked Joints (RBJ) will be presented. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Reevaluation of Japanese high-speed rail construction: Recent situation of the north corridor Shinkansen and its way to completion

Since the inauguration of the first “Shinkansen” high-speed railway line in Japan—the Tokaido Shinkansen—in 1964, Japan's high-speed railway lines have been a great success. On the other side of the coin, however, Japan's second phase of constructing high-speed lines, which was first planned in 1973, has made little progress over many years. It is thus interesting to consider why such a contrast between the former success and latter stagnation of Shinkansen construction has come about. While the competitiveness of high-speed railways has been reevaluated, and as various countries around the world introduce high-speed rail lines, this matter has become one of great interest. In our current research, first, it is shown that under an environment that has become surrounded by railways in Japan over recent years, these high-speed rail lines—which in Japan in the past have been called unnecessary public work projects—in fact have a significant competitive edge over other projects. As one of these lines, the Hokuriku Shinkansen, which links Tokyo and Osaka via a northern route from Tokyo that passes through the Hokuriku region, is taken up by this study and reevaluated. In doing so, considering that the reason for not precisely evaluating this line is the fact that the layout of the 100 km section of line near Osaka is not yet determined, the authors present and compare several routes for this section. As regards the evaluation of these routes, several distinctive ideas-such as routes utilizing part of the Tokaido Shinkansen line and using gauge-changeable trains are incorporated. As well as performing a detailed cost-benefit analysis, this study investigates all conceivable technical problems concerning the line. Furthermore, in the event of further increasing train speed, it is clearly shown that passenger flow through the central region of Japan will change significantly, thus generating significant demand and increasing user benefits. By precisely evaluating a high-speed railway line, this analysis has revealed the prospect of introducing such a line. Moreover, by presenting the finding of Japan—which has accumulated an extensive knowledge of high-speed railway lines—it will contribute to the evaluation of the high-speed railway lines being considered under the key transport policies of many countries around the world.

2 Rethinking the Poverty Line in Japan(Rethinking Disadvantageous Society : Viewing from the Poverty and Education Inequality Issues)

2 Rethinking the Poverty Line in Japan(Rethinking Disadvantageous Society : Viewing from the Poverty and Education Inequality Issues)

Comparison of wheel/rail noise radiation on Japanese railways using the TWINS model and microphone array measurements

The railway noise from conventional narrow-gauge lines in Japan mainly consists of rolling noise. A better understanding of rolling noise is required to reduce the noise at the wayside. In the past, in order to quantify wheel/rail noise, theoretical models, such as TWINS, have been developed, and measurements have been carried out with microphone arrays. The TWINS model has been validated in terms of noise and vibration, and used to predict the rail and wheel contributions to the total noise. Results from microphone arrays often give more prominence to the wheel than these predictions. In this paper, the TWINS model is applied to Japanese railways. Through comparisons of predictions with measurements for four types of wheel and one track type, it is shown that the TWINS model gives reliable predictions. Simulations are presented to represent a microphone array. These show that, in the frequency region where waves propagate freely along the rail, the microphone array can significantly underestimate the rail contribution to the noise.

Development of Quakeproof Reinforcement Methods for Masonry Walls

Railway lines in Japan are sometimes fl anked by earthretaining structures consisting of piled-up stones, known as masonry walls (see Fig. 1). Although railway operators are aware that these walls can collapse and damage trains in the event of an earthquake, the behavior of such structures when subjected to seismic motion has not yet been clarifi ed. Against this background, the Railway Technical Research Institute (RTRI) investigated the deformation mechanism of masonry walls in earthquake conditions. Based on the results of this research, a technique called the pin-up method was developed to effectively reinforce masonry walls against earthquakes. A model collapse test on a masonry wall revealed that its backfi ll cobblestones slid outward due to the relative movement between the ashlars on the front and the ground behind, thereby generating residual displacement in the wall. In view of these deformation-causing factors, the earthquake resistance of masonry walls is expected to improve if the movement of backfi ll cobblestones can be suppressed. It is therefore thought that measures to fi x these cobblestones using grouting materials will provide an effective means of helping masonry walls to resist earthquakes. However, these cobblestones play a role in draining water that penetrates the ground, thereby preventing it from applying pressure to the backside of ashlars. If grouting material is injected into the backfi ll cobblestone layer at random, this drainage function may be lost. The RTRI therefore designed the pin-up method (types I and II) to enable the suppression of backfi ll cobblestone movement while maintaining its drainage function (see Fig. 2). Type I of the pin-up method combines four adjacent ashlars and the backfi ll cobblestones in the wall behind them to create stiffening blocks, thereby achieving the goal of improving the earthquake resistance of the masonry wall while maintaining the drainage function of the backfi ll cobblestones and suppressing their movement. Type II, on the other hand, also anchors the combined stiffening blocks to the ground using deformed bars, and is applied when the level of earthquake resistance required is higher than that offered by type I. Pin-up method types I and II are so named because they can be likened to fi xing masonry walls to the ground with pushpins. Figure 3 shows the results of shaking table tests to verify the effect of earthquake reinforcement work applied to model masonry walls using pin-up method types I and II. When the models were subjected to sinusoidal wave excitation at a maximum acceleration of 7 m/s2, deformation was suppressed to one-third or less that of a non-reinforced wall with the model reinforced using pin-up method type I. On the other hand, the model reinforced using type II showed virtually no deformation at all. As these test results demonstrated that masonry walls reinforced using the pin-up method have a high level of earthquake resistance, the RTRI discussed concrete methods of reinforcement in consideration of actual conditions, clarified the quality of applicable grouting materials and decided on suitable methods of injection. Based on the results of model tests, the Institute also determined methods to evaluate the degree of deformation in masonry walls in earthquake conditions, evaluate their stability and design reinforcement work using the pin-up method. By summarizing these study results, the RTRI was able to create a manual for design and reinforcement work related to masonry walls. In January 2009, the pin-up method was applied in actual masonry wall reinforcement work for the fi rst time (see Fig. 4). The RTRI will strive to promote the adoption of this method over wide areas in order to contribute to the improvement of disaster prevention for railway wayside slopes.

Control Methods to Enhance Large-scale Inverter Output Voltages

A linear synchronous motor (LSM) with onboard superconducting magnets and coils on the ground is being used on the Yamanashi Maglev (magnetic levitation) Test Line in Japan. The power converter that drives the LSM needs to generate power of variable voltage and frequency as dictated by the speed and thrust of the train. A pulse width modulation (PWM) inverter was therefore designed and several control methods were then developed to enhance the output voltage of the inverter without change its circuitry. This paper describes the different control methods that were developed and tested in order to ultimately reduce manufacturing costs and expedite the commercialization of the maglev system.

Improving Maglev Vehicle Characteristics for the Yamanashi Test Line

This paper reports on the results of two new types of vehicles that have been manufactured for the Yamanashi Maglev (magnetic levitation) Test Line in Japan. The Mc5 leading car was designed to test the reductions in tunnel micro-pressure waves resulting from an improved nose shape. The M4 is a prototype commercial car intended to improve ride comfort and reduce interior noise. The paper describes the technical developments that lead to these improvements and reports on the various characteristics and the reduction in side window noise and vibration.