Compensation system for the thermal expansion of a main cable comprising a first main cable portion and a second main cable portion, two portions both extending along one direction, said longitudinal direction, and arranged between two distinct attachment points, said first and second main cable portions each being respectively connected to an attachment point, said compensation system comprising: - at least one traction cable extending substantially parallel to said longitudinal direction and comprising a first end and a second end, said first end being attached to said first main cable portion; - an adjusting device for regulating the tension of said main cable, comprising: o a first fixing point to which said second end of said traction cable is mechanically connected; o a second fixing point to which said second main cable portion is mechanically connected; and o return means arranged between said first and second fixing points (31; 32) and being configured to enable mechanical tension to be exerted between the first fixing point and the second fixing point in order to compensate for thermal expansion of said main cable, said compensation system being characterized in that said return means comprise at least one cam and a torsion spring: - said at least one cam surrounding said torsion spring so as to allow winding of said second end of said traction cable; - said torsion spring comprising a first anchoring rod and a second anchoring rod: o said first anchoring rod being integral with said cam so as to form the first fixing point; o said second anchoring rod being mechanically connected to said second main cable portion so as to form the second fixing point, and o said torsion spring being configured to allow mechanical tension to be exerted between the first fixing point and the second fixing point. - at least one traction cable extending substantially parallel to said longitudinal direction and comprising a first end and a second end, said first end being attached to said first main cable portion; - an adjusting device for regulating the tension of said main cable, comprising: o a first fixing point to which said second end of said traction cable is mechanically connected; o a second fixing point to which said second main cable portion is mechanically connected; and o return means arranged between said first and second fixing points (31; 32) and being configured to enable mechanical tension to be exerted between the first fixing point and the second fixing point in order to compensate for thermal expansion of said main cable, o a first fixing point to which said second end of said traction cable is mechanically connected; o a second fixing point to which said second main cable portion is mechanically connected; and o return means arranged between said first and second fixing points (31; 32) and being configured to enable mechanical tension to be exerted between the first fixing point and the second fixing point in order to compensate for thermal expansion of said main cable, - said at least one cam surrounding said torsion spring so as to allow winding of said second end of said traction cable; - said torsion spring comprising a first anchoring rod and a second anchoring rod: o said first anchoring rod being integral with said cam so as to form the first fixing point; o said second anchoring rod being mechanically connected to said second main cable portion so as to form the second fixing point, and o said torsion spring being configured to allow mechanical tension to be exerted between the first fixing point and the second fixing point. o said first anchoring rod being integral with said cam so as to form the first fixing point; o said second anchoring rod being mechanically connected to said second main cable portion so as to form the second fixing point, and o said torsion spring being configured to allow mechanical tension to be exerted between the first fixing point and the second fixing point.