This thesis discusses a new approach to improve the existing emergency power system (RAT assembly) in aircraft to integrate it in more electric aircraft (MEA). Indeed, the MEA has a high demand of electric energy and it is difficult for the existing emergency power system to provide it. To meet this demand, the alternative chosen is the connection of lithium-ion batteries in parallel with the RAT assembly. In order to integrate these batteries, two power converters and one braking resistor are used. The first one is a voltage controlled dc-dc converter. His role is to maintain a dc bus of 270V from the batteries voltage. The converter is bidirectional allowing the RAT assembly to recharge the batteries. The second converter is an inverter, his goal is to converts the dc bus in a three-phase voltage of 200V at a frequency of 400Hz. The ac-dc converter is controlled by current and aims to regulate the speed of the RAT assembly generator (ADG). According to the technical specifications provided by Bombardier Aerospace (B.A.), the RAT assembly is modeled in Simulink® / SimPowersSystems™ (SPS). From test results of B.A., the model of the RAT assembly is validated. Simulation results obtained from the model are similar to those obtained in experimental tests. Also, detailed models of the converters are constructed. The topology and the control of each one are explained in details. From the RAT assembly model and those of the two converters, the simulation model of the hybrid emergency power system is built. Finally, two simulations are made with the new design. The first simulation takes into account the characteristics of a Bombardier Global Express aircraft, while the second takes those of a Bombardier CRJ-900. The results of the two simulations show that the newly developed emergency system works as it should. The batteries can provide power greater than the rated power of the ADG to the essentials loads.
| Date | 21 Dec 2011 |
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| Original language | French |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Louis-A. Dessaint (Supervisor) |
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Bérubé, D. (Author),
Dessaint (Supervisor),
21 Dec 2011Student thesis: Master's thesis › Master in Engineering: Electrical Engineering