Modeling and control of bidirectional DC-DC converter fed PMDC motor for electric vehicles

This paper presents modelling and control design for a bidirectional dc-dc converter fed permanent magnet dc (PMDC) motor traction drive system for EV applications. The incorporation of the half bridge non-isolated bidirectional dc-dc converter improves the efficiency by allowing the provision for energy regeneration during braking (in the case of an EV or an HEV) and during down slope motion (in case of a pedalled electric bicycle). The state space averaging technique has been used to obtain the small signal model of the system. A unified PID controller working in both the modes i.e motoring and regeneration has been implemented for the speed control. The soft switching technique has also been incorporated to minimize the switching losses as well as to address the issue of parasitic ringing. The system model has been simulated in the MATLAB/SIMULINK and the results have been verified with the theoretical calculations.