Discontinuous conduction mode three phase buck-boost derived PFC converter for more electric aircraft with reduced switching, sensing and control requirements

In more electric aircraft (MEA), three phase power factor correction (PFC) rectifiers of several kilowatts are required. In this paper, a three phase buck-boost derived PFC converter with inductors connected in delta configuration for aircraft application is presented. The proposed converter is operated in discontinuous conduction mode (DCM) to achieve PFC at ac input. This avoids the inner current control loop which further eliminates the current sensors. It requires only one output voltage sensor unlike five sensors in conventional PFC converter and uses a simple voltage control loop to regulate the output voltage. This makes the system cost effective, more reliable and robust. The steady state operation, design calculations and simulation results are presented. The experimental results from a 2kW laboratory prototype are also presented to confirm the operation of the proposed converter.