Verification Tests of Energy Storage System for DC Electrified Railways using EDLC

• Published in: Quarterly Report of RTRI Vol. 48; no. 2; pp. 71 - 77
• Main Authors: KONISHI, Takeshi, HASE, Shin-ichi, NAKAMICHI, Yoshinobu
• Format: Journal Article
• Language: English
• Published: Tokyo Railway Technical Research Institute 2007; Japan Science and Technology Agency
• Subjects: electric double-layer capacitors; energy storage system
• ISSN: 0033-9008; 1880-1765
• DOI: 10.2219/rtriqr.48.71

Power-source stabilization methods such as measures against voltage drop, power loading fluctuation and regenerative power lapse represent important issues in DC railway-feeding circuits. Providing an energy storage medium that uses power efficiently and reduces the problems mentioned above is therefore a major concern. The development of such a medium has attracted public interest, with several energy storage applications (including batteries and flywheels) already having been investigated. A wide range of large-scale electric double-layer capacitors [EDLCs] that are rapidly charged and discharged have been developed, and offer durability, maintenance-free features, low-pollution and high efficiency. For their fundamental study, we produced a prototype DC electrified railway energy storage system consisting of EDLCs, a diode bridge rectifier, a chopper system and a pulse-width modulated [PWM] converter, with useful information obtained from charge/discharge tests. Based on these results, two energy storage systems were built for DC 600 V and DC 750 V, and verification tests were conducted in conjunction with the Enoshima Electric Railway Company Ltd. and the Osaka Municipal Transportation Bureau. It was confirmed through verification tests that energy storage using electric double-layer capacitors provided effective functions to DC 600V and DC 750V railway systems. The tests proved to be a guideline for actual application in DC 1,500V or DC 3,000V railway systems.