Control of a DC-DC Converter as an Active Filter in Combination with Switched Reluctance Generators for Gas Turbine Applications
Duc Pham, Annegret Klein-Heßling, Rik W. De Doncker,
2019 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)
More-electric aircraft enable a sustainable increase of flights. Hybrid-electric drive train topologies allow to reduce the size of conventional gas turbines which are still inevitable in commercial aircraft. The high rotational speed of gas turbines offers a direct coupling with switched reluctance machines (SRMs) for electromechanical conversion due to their simple and robust structure. However, the output current from SRMs has a pulsating waveform at high speed causing an oscillation of the dc-link voltage. An active power filter is considered between the dc-bus of the distribution network and the dc-link of the inverter. With the proposed control scheme a decoupling of the two terminals is achieved satisfying voltage requirements for aircraft distribution systems. Furthermore, it reduces the current ripple of the SRM leading to reduced RMS current values. Simulations show the capability of designing active power filters with smaller electrical components compared to pure passive filters.