IRS 70797-1ed.

Annotation of standard text IRS 70797-1ed. :

The present IRS covers substations and traction units of modern interoperable design for traction units. In particular, it applies to the electrical protection system, provided for the following AC and DC (see Abbreviations and Symbols - page 6) electric traction systems, according to IEC 60850 (see Reference documents - page 5): - 25 kV - 50 Hz; - 25 kV - 60 Hz; - 15 kV - 16 2/3 Hz; - 1.500 V DC; - 3.000 V DC. The present IRS: - establishes railway specific protection principles; - describes the railway specific protection system functionality; - describes the protection system in relation to the electric traction system, which also comprises the interface information between the electric traction system and the electric rolling stock; - specifies principles for operation coordination of circuit breakers in substations and on-board tractive units. Coordination is required because: - the cut-out power of train-borne circuit breakers is limited whereas the level of short circuit currents may exceed it under some power supply voltages; - if there is no OCL voltage, the tractive unit circuit breakers must open within a maximum predefined time; - the conditions for automatic re-closing of substation circuit breakers must be compatible with the preceding conditions. Interoperability of traction units on electrified railways using different systems requires that the compatibility of the protection systems between traction unit and substation is verified, regardless of the rail network in question. Moreover, this document specifies the limit condition of the input filter load current on tractive units under direct current power supply so that substation circuit breakers will not trip unnecessarily. A software model has been created during the drafting of this IRS. It can be easily adapted to other use cases. It is available with the IRS download file.