Advanced generator design using pareto-optimization

Abstract

In upcoming and future more-electric airplanes more electrical loads connected to the power distribution network will behave nonlinearly and will be switching with advanced demands on the network to keep the power quality. While a lot of effort was already spent on techniques to design the network structure and filters, also the generators have to face the new demands and constraints. Trade offs between performance, weight, and latterly power quality have to be made and design choices have to be backed up by qualitative and quantitative measures. Therefore a convenient design tool chain was elaborated for an externally excited synchronous generator. Pre-existing analytic design functions containing electrical, mechanical and thermal analytical models were expanded by a new criterion for power quality. This criterion defined by industrial standards was included via virtual tests by timedomain simulation. Frequency domain criteria were gained in simulation by new signal property monitor blocks. Standards' conformance is visualized conveniently. A state of the art genetic algorithm similar to NSGA-II was applied to generate the Pareto-front of contrary design trade offs. Several convenient visualizations of the Pareto results are presented, which clearly link the parameters, tuners and output results. To ease the transition from theoretical design to the 3d mechanical layout, a CATIA model of the optimized generator candidate is generated directly from Matlab.

Multi Electrical Machine Pre-Design Tool with Error Handling and Machine Specific Advanced Graphical Design Aid Features Based on Modelica

“…Regarding motors using magnets: appearance and proliferation of Surface Mounted Permanent Magnet Synchronous Motors, internal Permanent Magnet Motor Family, emerge and intensive development due to magnet's price raises (substitution of rare earth magnets by ferrite magnets) and increased power density requirements (keeping rare earth magnets in geometrical configurations meant to achieve high airgap flux). Regarding externally excited Synchronous Machines [1]- [2], its ability to work in four quadrants and to work under very high temperatures (where magnet motors get demagnetized) made them resurge in micro generation, both in land and aviation fields. These new appearances did not pull back Induction Machines because of, as in Switched Reluctance Motors, its low construction and operation costs are still an advantage [3].…”