in order to finish the regeneration step in a short time and improve fuel efficiency , a regeneration control device for a post - processing device of a hybrid vehicle is constructed such that , at the time of deceleration during the regeneration of the post - processing device , the hybrid vehicle is driven by the electric motor , and the engine is controlled so as to retain a rotation speed suitable for the regeneration of the post - processing device in a manner irrelevant to the driving system , and a control force equivalent to the braking force provided by the engine brake is generated by the recovery of the electric motor .