Investigation into the design domains’ interdependencies of an inverter

Abstract

The continuous development of power electronic converters has opened new opportunities for the More-Electrical Aircraft (MEA) concept, where the conventional power sources (pneumatic, hydraulic, mechanical) are replaced with electric sources to support secondary loads in the aircrafts. It is expected that more efficient, lighter and lower maintenance solutions can be obtained with high power density power electronics. In order to obtain optimal designs for power system integration, new methodologies employing multi-objective optimization have been reported. However, the application of multi-objective optimization is more powerful with multi-domain modeling, which is not always a straightforward task. The reason is that power electronics design is a complex design problem, mainly because of the multi-disciplinary nature of its physical aspects (domains), including electric circuit behavior, thermal performance, electromagnetic compatibility issues and packaging constraints. Therefore, a subsequent modeling effort for the power electronics design is necessary to fully exploit the advantages of optimization techniques. To obtain a comprehensive insight in the system behavior, the mutual dependencies of the power electronics' design domains need to be characterized and quantified. This thesis investigates into the interdependencies between the design domains of an inverter for aerospace applications. In this thesis project a design methodology is developed based on the multi-domain approach. The converter design is treated as a system in a top level design aspect, leading to the selection of a topology, modulation and control strategy. In addition, the circuit level design is effectively decoupled into the electrical, EMI, thermal and mechanical design domains, which are treated independently. The boundaries of the design levels and domains are determined and the links between the design domains are established though their mutual dependencies. Based on this methodology, a design framework for an aerospace inverter is realized in software using analytical modeling. This framework is used to investigate the mutual dependencies of the design domains and the impact of the design choices on the inverter performance. The interdependencies of the design domains are manipulated using design variables, similar to an optimization problem, by employing parametric sweep. A high efficiency and high power density aerospace inverter is designed, according to the specifications of Aeronamic B.V. and aerospace regulations.