Abstract:
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The trend of the last years in the aeronautic industry is to reduce the weight
of the commercial aircrafts. This weight reduction implies the need for more
electrical power on board, since the heavy hydraulic drive system is replaced
by and an electromechanical system. In order to supply this amount of extra
electrical power, a Symmetric 270V DC Power Supply as a part of a Universal
Power Converter is presented in this thesis. The Universal Power Converter
generates the di erent airborne voltages - 32VDC, 270V DC and 230V AC-
using as Fuel Cell Stack as raw energy supply.
The thesis focus on the the power conditioning system includes three DC-DC
converters, generating regulated 270V DC output. The rst stage, a 3-phase
interleaved full-bridge soft-switching converter, so called V6, boosts the Fuel
cell voltages to a non regulated DC-Link bus with a voltage between the 320
and 580 Volts. The following stage, composed of a SEPIC converter and C uk
converter parallel connected and in interleaving operation provide the regulated
output. The three converters of the proposed conditioning system has been
studied obtaining the design equations, sized the components and then veri ed
with computer simulations using Matlab Simulink. The simulation results
show regulation in the entire range of load with and excellent result within
the Continuous Conduction Mode of the converter, a high performance of 93%
at full load and a small current ripple at the Fuel Cell input, less than 17%
peak-to-peak of the drawn current at full load.
Furthermore, this thesis presents the Universal Power Converter at system level,
to place the reader in context. The system supplied with a 16kW Proton
Membrane Fuel Cell is designed to generate di erent outputs: 32Vdc at 5kW,
270Vdc at 16kW and 230Vac at 16kW; supplying at a time three, two or one
voltage. Furthermore, the selected Fuel Cell is introduced and a Simulink model
is build to perform simulations of th econverters. |