Online Impedance Measurement of Cascaded DC/DC Converters

Distributed power systems (DPS) offer flexibility, cost reduction, energy efficiency and ability to integrate multiple sources and loads. DPS are multi-converter systems and its design needs for special attention to the dynamic interaction between the power converters. The output and input impedance of the converters are the key parameters to study and ensure the stability of the system. Modern digital controllers allow for the online measurement of the output impedance of the converters and the integration of new capabilities such as monitoring and stability surveillance. The controller can measure the dynamic condition of the system and make decisions about the tuning of compensators. This work describes the online measurement of the impedance of a converter supplying another power converters using an auto-identification system implemented in the digital controller.