Traction box of a railway vehicle with a cooling system, associated application method and railway vehicle

1. The traction box ( 10 ) of a railway vehicle, comprising:

first ( 16 , 17 ) and second ( 18 ) pieces of electric equipment, and

a cooling device ( 20 ), able to remove heat dissipated by said first and second pieces of electric equipment,

the cooling device comprising:

first ( 54 , 62 , 70 , 71 ) and second ( 54 , 60 , 70 , 71 ) fluid circuits, respectively crossing heat exchange areas with the first and second ( 40 ) pieces of electric equipment, each of the first and second fluid circuits forming a closed loop; and

first ( 34 ) and second ( 36 ) heat exchangers, respectively crossed by said first ( 54 ) and second ( 60 ) fluid circuits and allowing a heat exchange between said fluid circuits and a first air flow ( 32 ),

wherein:

the first and second fluid circuits comprise a first common conduit ( 70 , 71 , 54 ) for fluid circulation, crossing the first heat exchanger ( 34 ); and

at an outlet ( 58 ) of said first heat exchanger, said first conduit is connected to second ( 60 ) and third ( 62 ) conduits parallel to the circulation of fluid, said second conduit ( 60 ) belonging to the second fluid circuit, said second conduit first crossing the second heat exchanger ( 36 ) and then the heat exchange area ( 40 ) with the second piece of electric equipment ( 18 ).

2. The traction box according to claim 1 , wherein the cooling device ( 20 ) further comprises a device ( 66 ) for regulating a fluid flow rate in the second ( 60 ) and/or third ( 62 ) parallel conduits.

3. The traction box according to claim 2 , wherein the regulation device ( 66 ) and the second ( 60 ) and third ( 62 ) conduits are configured for a lower flow rate in the second conduit ( 60 ) than in the third conduit ( 62 ).

4. The traction box according to claim 1 , wherein the heat exchange area ( 38 , 39 ) with the first pieces of electric equipment is positioned on the first common conduit for fluid circulation.

5. The traction box according to claim 1 , wherein the heat exchange area with the first pieces of electric equipment is formed with at least two heat exchange units ( 38 , 39 ), positioned in parallel on the first fluid circuit.

6. The traction box according to claim 1 , including a first fan ( 30 ) able to generate the first air flow ( 32 ), said first air flow crossing the first ( 34 ) and second ( 36 ) heat exchangers.

7. The traction box according to claim 6 , configured so that the first ( 34 ) and second ( 36 ) heat exchangers are positioned in parallel in the first air flow ( 32 ).

8. The traction box according to claim 6 , including a closed compartment ( 12 ) wherein are located the first ( 16 , 17 ) and second ( 18 ) pieces of electric equipment, said closed compartment being isolated from the first air flow ( 32 ).

9. The traction box according to claim 1 , wherein the cooling device comprises a second fan ( 42 ) able to generate a second air flow ( 44 ) towards the second piece of electric equipment ( 18 ),

the heat exchange area with the second piece of electric equipment comprising a third heat exchanger ( 40 ) positioned between the second fan and the second piece of electric equipment ( 18 ), said third exchanger thus being able to cool the second air flow upstream from said second piece of electric equipment.

10. A method for applying a traction box ( 10 ) according to claim 1 , comprising the following steps:

circulating a heat transfer fluid in the first common conduit ( 54 ) crossing the first heat exchanger ( 34 ), reducing a temperature of said heat transfer fluid by heat exchange with the first air flow ( 32 ) as far as a first value (T 1 ) at the outlet ( 58 ) of said first heat exchanger; and then

circulating a first portion and a second portion of said heat transfer fluid respectively in the second ( 60 ) and third ( 62 ) parallel conduits,

crossing the first portion of heat transfer fluid at the second heat exchanger ( 36 ), reducing a temperature of said heat transfer fluid by heat exchange with the first air flow ( 32 ) down to a second value (T 2 ), crossing said first heat transfer fluid portion at the heat exchange area ( 40 ) with the second piece of electric equipment ( 18 );

and

crossing the second portion of the heat transfer fluid, at a temperature greater than the second value (T 2 ) at the heat exchange area with the first pieces of electric equipment ( 16 , 17 ).

11. A railway vehicle including at least one traction motor controlled by a traction box ( 10 ) according to claim 1 .

12. The traction box according to claim 7 , including a closed compartment ( 12 ) wherein are located the first ( 16 , 17 ) and second ( 18 ) pieces of electric equipment, said closed compartment being isolated from the first air flow ( 32 ).