Adaptive Impedance-Based Stabilization of Multi-Bus DC Power Distribution Systems Using Positive Feed-Forward and Resonance-Enhanced Voltage Controller

In this work an adaptive stabilization control scheme is proposed for multi-bus DC power distribution systems. Multibus DC systems are generally formed by several intermediate converters that interconnect the upstream source and downstream load converters. Therefore, in such systems, the stability of multiple buses is of concern due to the interactions among the tightly-regulated interconnected converters. Based on the operating conditions, either the source-or load-side buses could be unstable or prone to instability. In this work, the stability of each bus will be analyzed using the measured respective bus impedance. In the proposed control scheme, an intermediate converter utilizes both adaptive positive feed-forward and resonance-enhanced voltage control strategies, which can stabilize the source-and load-side buses respectively. Therefore, this converter, using the measured bus impedances, is capable of detecting which of the two buses is more prone to instability and activating the relevant stabilizing controller. Simulation and experimental results are provided to validate the effectiveness of the proposed control method.