A Minimum DC-Link Capacitance Estimation and Robust Voltage Control for an N-Phase Interleaved Boost Converter Supplying a Traction Inverter

There is a growing demand for high-power-density powertrains in electric and hybrid vehicles to increase the space available for passengers and/or other high-technology electronics. The dc-link capacitor bank occupies a large volume in traction inverters, so minimizing the needed capacitance reduces system volume. Thus, in this paper a numerical method is proposed to estimate the minimum required dc-link capacitor value. Then a novel control strategy, which integrates the current loop with an energy loop, is proposed for the interleaved boost dc-dc converter supplying a traction inverter. The impacts that the inductor value and control settling time of the dc-dc converter have upon the system stability are analyzed. The feasibility and effectiveness of the proposed controller are validated through experimental studies using a three-phase boost-interleaved dc-dc converter connected to a three-phase inverter.