Passivity Enhancement Strategy for Voltage-Controlled Aviation Converters with High Harmonic Mitigation Performance

The rapid advancement of more electric aircraft technology has led to the widespread integration of non-linear loads into aircraft power supply systems. Passivity-based control (PBC) is a well-established method for enhancing system stability. However, existing research mainly focuses on current-controlled converters with control strategies confined to the fundamental component, while studies on passivity control for voltage-controlled converters incorporating harmonic mitigation remain limited. To enhance the stability of the standalone converters in aircraft power systems, this paper first proposes a method that transforms the converter output impedance into a product of two sub-impedances, thereby revealing the compensation mechanism of the output current feedforward active damping on the converter output impedance. Based on this insight, a second-order generalized integrator based active damping strategy is introduced to achieve sub-impedance phase compensation. Furthermore, to mitigate the adverse effect on converter passivity introduced by resonant controllers, a phase lead angle design strategy is proposed to ensure converter passivity from 0 Hz to the Nyquist frequency without compromising harmonic mitigation capability. Experimental results on a 5 kW three-phase converter validate the effectiveness of the proposed method.