An improved step-down conversion ratio interleaved buck converter for aircraft applications

This paper proposes an improved step-down conversion ratio interleaved buck converter which is suitable for aircraft applications. Power supply systems in the aircrafts usually utilize a high voltage dc bus, but the fly-wire control systems consist of electro-magnetic actuators generally works in low voltages (24V-30V). The proposed converter can provide a much lower output voltage with a moderate duty ratio, instead of an extremely short duty ratio. It also reduces the voltage stress across the switches and diodes and thus efficiency of the converter is improved. Pre-requisite for the above mentioned advantages is the pre-charging of blocking capacitors. In this paper, a novel concept of pre-charging using a snubber circuit is proposed thereby avoiding a dedicated circuitry for pre-charging. The snubber circuit takes care of pre-charging at start and snubber function for the rest of the operation. This paper also explores some other advantages of the proposed topology. Simulation results of proposed converter topology are presented to justify the theoretical analysis.