Development of Contact-Loss Measuring System Using Ultraviolet Ray Detection

1. Development of Contact-Loss Measuring System Using Ultraviolet Ray Detection Pantograph Catenary Interaction Framework for Intelligent Control December 8th ,2011 Amiens, France Takamasa HAYASAKA Railway Technical Research Institute

2. Table of Contents 1. Motivation Contact loss, measurement, conventional system and technical issues 2. Development Japanese Contact-Loss Measuring System Development of new measuring system 3. Verification Tests and Results Verification test of the new measuring system 4. Summery and Future plane

3. Feature of Japan and Japanese Railway Network Feature of Japan Distance：3,000km Area：380,000 km2 Population：128,000,000 Feature of Japanese Railway Network All Railways：10,000km High-speed railway：2,400km Aomori 福島 Tokyo Osaka Since many people live along railway, railway companies pay attention to noise generation. Kagoshima

4. Influence of Contact-loss Whatis problem by contact-loss? At the moment of arc discharge occurring and extinction, it generates noise. moreover Current collecting materials take a damage during arc discharge. Contact wire Pantograph head

5. Prevent Contact-loss We make an effort to prevent contact-loss. In other words, we are trying to improve current collecting character. For example, Shape Air Conditioning unit Developing new types of pantograph system Developing new types of overhead contact system

6. Necessity of Contact-loss Measurement We need those researches to prevent contact losses, however, we also need to know where contact losses occur, for preventing unusual wear of current collecting material. Contact-loss is measured in various situations such as certification of a new line, line test for a new type train set, inspection of overhead contact wire and so on.

7. How to Measure Contact-loss There are some measurement ways to detect arc light. One example of the measurement for arc light detection system installed on a train is shown below. Contact wire Pantograph Acquisition device Optical fiber detector Acceptor ・Optical fiber and acceptor are fixed on the train roof. ・The optical fiber is connected to a detector installed in the train. ・The detector is connected to data acquisition system.

8. Conventional System to Detect Arc Light Output Output Arc light consists of some optical wave lengths, though, the ways of arc light detection are two types from view points of optical wave length. One is ultraviolet rays detection, the other is visible rays detection. There is the difference in optical fiber of these systems. Ultraviolet rays detecting system Visible rays detection system Ultraviolet rays Visible rays Infrared rays Quartz optical fiber Detector Interference filter Arc light Ultraviolet rays Visible rays Infrared rays Plastic optical fiber Detector

9. Japanese Conventional System to Detect Arc Light In Japan, railways company used to the visible rays detection systems. But the system has a disadvantage that it can not measure arc light in daytime. So, they hoped to adopt the ultraviolet rays detection system. However, also the ultraviolet rays detection system has a disadvantage that it uses quartz optical fibers.

10. Development of New System Output In development of Japanese contact-loss measuring system using ultraviolet ray detection, we tried adopting plastic optical fibers that can not transmit ultraviolet rays. In other words, we decided to use the visible rays detection system for development of contact-loss measuring system using ultraviolet ray detection. • If we can transform ultraviolet rays to visible rays in front of plastic optical fibers, we can use the system for contact-loss measuring system using ultraviolet ray detection. Transform Ultraviolet rays Visible rays Infrared rays Plastic optical fiber Detector

11. Interference filter Fluorescent glasses How to Transform Wavelength • We developed a wavelength transformer that transforms ultraviolet rays to visible rays. • Wavelength transformer Ultraviolet ray Visible rays • Plastic optical fiber • Wavelength transformer If we attach the transformer to plastic optical fiber’s acceptor, we can detect ultraviolet rays using visible rays detection system.

12. Transmissibility (%) Fluorescent glasses Wavelength (nm) Detectable Wavelength • Arc light has various wavelength, though, there are special wavelength ranges that has strong intensity. • So, we developed the interference filter that can transmit light of 200-240nm. 200-240 nm Relativity intensity 320-335 nm Wavelength (nm) We adopted a fluorescent glasses developed by Dr. Sawanobori [7].

13. Angular Characteristic • The system has an output change with an angle deviation of light incidence. • This result is the output ratio when light incidence deviates from vertical line against acceptance surface. Output ratio When light goes straight to acceptor, the output is 1. But when the light deviates from vertical line, the output become a little small against vertical line’s output. Angle (degree)

14. Output by Short Time Arc • This is whether the system can detect short time arc. We made an arc generator to test it. • The test condition is 50V and 100 A. Voltage of between electric contacts (V) • This is the voltage of between electrodes. 94 μsec • This is the output of the system. Output voltage of the system (V) • The system can detect short time arc. 0 0.1 0.2 0.3 0.4 Time (sec)

15. Verification Test After tests of basic characteristics of the system, we verified the system by two tests, laboratory and on-board test. • In laboratory verification, • We used the equipment with rotating disk and pantograph. Rotating disk Pantograph • In on-board test, • We used a inspection car in Shinkansen.

16. Result of Verification Test • This is the result of on-board test. The test car has two pantographs. The pantograph of car number 5 is taking large current while the pantograph of car number 12 is losing contact. • Arc detector is detecting arc light until the current crosses zero. Car No.5 Current Car No.12 Current Car No.5 Arc detector Car No.12 Arc detector Time (s)

17. User of This System in Asia • We tested the system step-by-step. Now, the users of the system is gradually increase. • Shinkansen’s inspection car • Low speed railway’s inspection car • High speed railway’s test car • High speed railway’s inspection car

18. Summary • We developed contact-loss measuring system using ultraviolet ray detection. • In the system, although plastic optical fiber can not transmit ultraviolet rays, we adopted it. • We made a transformer that can transform ultraviolet rays to visible rays. • The systems were verified in some tests. • Now, the system is being used in many railway companies.

19. Future Plan We also research arc phenomena between contact wires and contact strips. In the research, we are trying to solve the wearing mechanism by arcing. Arc trace of Contact wire The amount of wear by arc are proportional to energy between electrodes. So, if we can measure the energy at a distance from electrodes, we can estimate the amount of wear. The system can measure energy of light. We will show the relation between arc light energy and amount of wear. Arc trace of Contact strips

20. Thank you for your attention ご清聴ありがとうございます

21. Rotation disk 160μs 0.08 V Detector Light source Rotating disk：1500rpm 0.04ms/div

22. 0.15, 0. 3 , 0.6 Ω 50 V Thyrister Contact wire Contact strip