The railway line of the National Railway Infrastructure Company between Plovdiv – Svilengrad – Turkish /Greek borders, Section Harmanli-Svilengrad – Phase 4.2
Brief description of the project Harmanli – Svilengrad
The railway line of the National Railway Infrastructure Company between Plovdiv – Svilengrad – Turkish /Greek borders, are re-constructed and electrified with 25 kV, alternating current, 50 Hz with overhead catenary system, supporting maximum speed for traffic of 160 km/h for the conventional trains and 200 km/h for trains with tilting car-bodies.
The catenary, single-phase, 25 kV, 50Hz, AC along the Railway section Dimitrovgrad – Harmanli – Svilengrad – Turkish/Greek borders in Bulgaria, is implemented to be compatible with the Trans-European high-speed railway system and within working conditions that allow safe and continuous running of high-speed trains.
The design speed of Plovdiv – Svilengrad railway line is 160 km/h (maximum 200 km/h for tilting trains), with catenary for speeds within the range of 200 km/h.
The overhead contact line is designed for work with the Bulgarian standard profile, gauge GC and pantograph with 1950 mm wide and with 1600 mm wide.
The catenary, consists of:
• a bronze messenger cable of 70 mm2 for main line, and 50 mm² for secondary line (Bz II – DIN 48201).
• a copper silver contact wire of 120 mm2 for main line, and a copper contact wire 80 mm² for secondary line (CuAg0.1 AC-120 and Cu-FRHC AC-80 – EN 50149).
• a return wire of ACSR 185/30 (DIN 48204).
The contact wire is suspended from the messenger cable at the support with stitch wire with 35mm² bronze cable (Bz II – DIN 48201) and 10mm² bronze cable (Bz II – DIN 43138) droppers on span for main line.
The contact wire material permits to use plain carbon contact strips for pantographs.
• The mechanical tension of the messenger cable is 1500 daN.
• The mechanical tension of the contact wire is 1500 daN.
• The mechanical tension of the stitch wire is 280 daN.
• The catenary system is to operate at temperature of environment of -30°C to +40°C (conductors temperature up to 80°C).
• The mechanical tension of the equipment will be maintained throughout the temperature range using balance weights and a tension wheel system, with a 3:1 reduction factor.
The poles are concrete, metallically ‘H’ section beams made of galvanized and on stations hard spans and multitrack console with poles made by 2‘H’ profile.
The concrete poles are mounted in the concrete foundation. The metallically poles are mounted on the foundations with bolts.
The catenary system, in general, is supported by a simple cantilever made from aluminum alloy.
The return circuit of the traction current was done with return conductor, traction rails and earth.
The design allow to the people safe and correct operation of the adjacent electrical installations by ensuring the following protection measures:
· measures against electric shock through direct touch of elements under voltage (protection with distance, obstacle protection, laying of warning signs);
· measures against electrical shock in case of indirect touch of elements under voltage (protection by earthing the traction network to the ground through connections to the earthing plates);
· measures against electro-magnetic impacts (of resisting, inductive and capacitive nature).