Mitigating the impedance-based interaction in DC distributed power systems

This paper presents a method to eliminate the sensitivity of impedance-interaction between source and load converters in a DC distributed power system (DPS). The impedance-interaction adversely alters the dynamic performance of the switched-mode converters, in a DPS, leading to destabilizing the voltage at their point of interface. Therefore, the proposed method lowers the interaction level by shaping the magnitude of the source converter output impedance (Zo(s)). Reducing the magnitude of Zo(s) mitigates the impedance-interaction and, consequently, improves the dynamic performance of each converter. The proposed controller utilizes the output voltage (Vo) of the source converter in order to reduce |Zo (s)| by a factor of (1 + Vo). The controller is effective with output voltages as low as 1 V because 1 V will reduce |Zo(s)| by 6 dB. The controller was experimentally validated in order to prove the offered theoretical analyses and time-based simulations.