A PFC topology with low input current distortion suitable for aircraft power supplies

Abstract

This paper presents an AC-DC converter topology for realization of PFC converters for applications where the mains frequency is high and a low input current harmonics is required, e.g., in aircraft power systems. The proposed topology eliminates crossover distortion due to the presence of input rectifiers and the inevitable input current phase lead. The idea is to stack a DC voltage on top of the AC mains voltage to prevent voltage polarity reversal in the input, eliminating the input bridge rectifier. This eliminates the crossover distortion, which can be significant for supply systems having a high mains frequency. In addition, the proposed PFC converter allows bi-directional energy flow, ensuring all inductors work in continuous conduction mode and hence eliminating the distortion due to the abrupt change of dynamic response when the operating mode changes. Analysis and design of the power and control circuits will be given and discussed. An experimental system will be presented for verification purposes.