Protection against unacceptable voltages in railway systems

Based on the system voltages for AC and DC railway systems the required voltage ratings for modern gapless MO surge arresters are given. The origin of overvoltages occurring in railway systems are explained, and some typical figures are presented. VDV recommendation 525 gives a protection concept for railway systems with Un = 600 V and Un = 750 V DC, including requirements for MO arresters. This protection concept is becoming common praxis in other DC railway systems as well, e.g. in 1500 V DC and 3000 V DC systems. The described concept provides protection of equipment against overvoltages originating from lightning and switching. For the protection against dangerous touch voltages low voltage limiters are used. These devices, generally based on gap technology, have the disadvantage of short-circuiting when stressed with impulses due to lightning. To overcome this problem a new hybrid voltage limiter, a combination of MOsurge arrester and low voltage limiter was developed and introduced. Tests with LVLs prove that these devices go in short-circuit conditions after the first impulse stress. LVLs with claimed lightning resistance withstand impulse stresses originated by lightning phenomena. Anyhow, the discharge voltage is changing after applied impulse stresses, being then in some cases out of the declared tolerances. The hybrid voltage limiter HVL turns out to be the only device that protects against overvoltages and touch voltages and provides reliable and safe protection.

• Record URL:
  http://railknowledgebank.com/Presto/content/Detail.aspx?q=UHJvdGVjdGlvbiBhZ2FpbnN0IHVuYWNjZXB0YWJsZSB2b2x0YWdlcyBpbiByYWlsd2F5IHN5c3RlbXM=&ctID=MTk4MTRjNDUtNWQ0My00OTBmLTllYWUtZWFjM2U2OTE0ZDY3&rID=Mzg1&qcf=&ph=VHJ1ZQ==&bckToL=VHJ1ZQ==&
• Authors:
  • Richter B
  • Bernhard A
  • Milutinovic N
• Conference:
  • AusRAIL PLUS 2007, 4-6 December 2007, Sydney, NSW, Australia
• Publication Date: 2007

Media Info

• Pagination: 7p.
• Monograph Title: AusRAIL PLUS 2007, celebrating the past, creating the future, 4-6 December 2007, Sydney, NSW, Australia

Subject/Index Terms

• TRT Terms: Design; Electricity; Railroad transportation; Vehicle safety
• ATRI Terms: Design; Electricity; Rail transport; Vehicle safety
• Subject Areas: Design; Railroads;

Filing Info

• Accession Number: 01516842
• Record Type: Publication
• Source Agency: ARRB
• Files: ATRI
• Created Date: Mar 4 2014 7:55PM