A new control scheme for DC-DC converter feeding constant power load in electric vehicle

Abstract

When a boost/buck DC-DC converter is added to the traditional voltage source inverters (VSI) drive system of electric vehicles (EV), the drive system is transformed into an electronic cascaded system. A new load current forward feed control strategy for the DC/DC converter is presented in order to improve the DC-link voltage stability. The small-signal model of the DC/DC converter with the proposed scheme is built, the theoretical analysis results based on which show the relationship between several important variables and the DC-link voltage stability. A PMSM drive system with boost/buck DC-DC converter modeled using MATLAB/simulink, and the typical operation condition in EV is simulated to verify the present strategy. The simulation and theoretical analysis results match with good agreement.