An assembly set and method for equipping a railway traction vehicle with brake energy recovery using standardised traction modules

An assembly set (1) comprising a non-operational railway traction vehicle (11) including a first main traction bogie (120) a main traction engine (12) for delivering traction power to the first main traction bogie (120); at least one second auxiliary traction bogie (160); at least one auxiliary installation space (16) for an auxiliary traction module (18a, 18b) for delivering traction power to the second auxiliary traction bogie (160); and a vehicle traction controller, characterised by an auxiliary regenerative brake traction module (18b). The assembly set having a preferred application to passenger diesel multiple unit and electric multiple unit train sets.