Modular Modeling and Bus-Port Impedance Analysis of DC Three-Stage Generator for More Electric Aircraft

DC three-stage generator (TSG) has been widely adopted as the main power source in aviation high-voltage dc power systems. With the increase in nonlinear loads, it poses challenges to the stability of the DC-TSG. Thus, the modeling of the system is important. In this article, a modular modeling method for the DC-TSG is proposed, and the overall model is established based on the two-port model of its each part, with a more accurate dynamic representation. This modeling method is simple, greatly facilitates design, and provides more physical insight into the system analysis. On this basis, the effects of the main exciter, output filter capacitor, and generator control unit on the bus-port impedance are discussed. Finally, the advantages and correctness of the model and theoretical analysis are verified by hardware-in-the-loop simulation.