A dq-Domain Impedance Measurement Methodology for Three-Stage Generator Cascade System in More-Electric Aircraft

The prevalent stability issues in power supply systems of more electric aircraft (MEA) arise from the constant power load characteristics of power electronic devices. Stability prediction can be effectively addressed using impedance-based criteria. This paper introduces a method that employs the MATLAB algorithm to inject positive and negative sequence voltage disturbances, facilitating d-q frame impedance measurement in a three-stage generator (TSG) cascade system featuring a PWM rectifier. The generalized Nyquist stability criterion (GNSC) is then applied to stabilize the AC common point. To validate the proposed method, a simulation model of the cascade system is meticulously established.