Retractable catenary
The retractable catenary system LU7 Concept is used inside maintenance workshops for High Speed Trains, Commuter and Regional train, or other electrified rolling stocks.
To ease the rolling stock roofing maintenance operation, the retractable rigid catenary enables:
In « Traction » position (unfold)
The arrival and departure of trains by electrical traction inside the building, the train electric motors testing, pantograph testing, and other operation requiring overhead contact line.
In « Retracted » position
The possibility of intervention over the trains, at all points, by means of roof working platforms, lifting platforms or baskets, or gantry crane on the total length of the workshops.
Specific intervention such as calibration adjusting of pantograph. The lifting of trains with lifting jacks for under-coach works.
To allow retracting the train electrification system, the overhead contact line, usually made of mechanically tightened hard copper contact cable, is substituted by an aluminium profile gripping a copper contact wire in its low part. The union of both aluminium profile and copper cable is thus named “rigid catenary”.
Rigid catenary is hung to several swivelling jib arms, motorized or not, according to the implantation drawing. The union of rigid catenary and jib arms is named « retractable rigid catenary ». The folding of the rigid catenary is achieved thanks to the simultaneous motorization according to the horizontal plan of all jib arms. The swivelling action to retract the catenary is only possible when all safety conditions are made: power supply of the catenary, footbridges accesses, gantry crane position, …
Each motorized jib arm is operated by a 0,37kW gear motor equipped with an integrated torque limiter. In order to avoid any shaking effect, the retractable catenary swivelling motion is made at variable speed. A variable frequency drive, common for up to 8 jib arms, enables a progressive starting phase as well as deceleration phase at the end of the swivelling process. This variable frequency drive is programmed for 3 speeds (acceleration, nominal, end of cycle) to make a smooth motion, without jolt and jerk.
Main characteristics of the LU7 Concept are the followings:
- Maximal distance between jib arms (span):……………up to 18m, 10-12m advised
- Length of jib arms:……………………………………………up to 6m
- Motorized jib arms ratio number:…………………………according to layout, from 1/1 up to 1/3 or minimum 1 each 24m of catenary
- Possible voltages:…………………………………………….all known, Direct Current or Alternative: from 750V to 25kV
- Time for one cycle (fold or unfold):………………………approx. 60s
- Maximal angle for retracted position:……………………up to 85° compare to the track perpendicular
- Positioning accuracy above the track:……………………+/- 20 mm
- Contact line height accuracy:…………………………………from +/- 4 to 25 mm, according to distance between jib arms
