Abstract: To improve metro vehicle curve passing performance, targeting B-type vehicle bogie with conical primary springs without third-rail current collection, a technical upgrade scheme of plug-in active steering same side drive is proposed. The active steering actuators in this scheme are directly connected to the front and rear axle boxes on the same side, while not associated with the bogie frame. Compared to conventional scheme, this scheme has advantages of simple structure and a minor and cheaper modification to the original bogie. A dynamic model is established, and a dynamics simulation analysis is emphatically carried out for the aspects including the influence of active steering curve on wheelset steering attitude through primary spring longitudinal time-varying stiffness, and the hunting stability. Analysis results show that the same side drive technical scheme can effectively improve the curve passing performance. Longitudinal time-varying stiffness doesn′t affect the same side drive steering attitude, and the critical hunting speed is higher than the maximum running speed requirement.