Bifurcation Analysis and Stabilization of DC Power Systems for Electrified Transportation Systems

Tightly controlled power converters are often modeled as constant power load. In transportation system, the input filters are small and not much damped to save weight/volume. In order to know when the system becomes unstable with those small LC filters and high cut-off frequency, the conventional analysis based on an average model may not be accurate enough. In this paper, a new discrete-time model is proposed to investigate the behavior of the studied system and to take into account the switching effect. A stabilizer is also proposed to increase the maximum power. This system is composed of a dc-dc boost converter with a modified control, an LC filter, and a constant power load. Experimental results confirm the validity of the proposed tool.