Power Distribution Algorithm and Steady-State Operation Analysis of a Modular Multiactive Bridge Converter

Electrical distribution systems comprising different power sources and loads, such as electric vehicles, aircraft electrical distribution systems, and residential microgrids, need new power conversion architectures. Multiport converters are an alternative to conventional multiconverter systems. This work studies a modular multiactive bridge (MMAB) converter, which is a multiport converter based on the connection of active bridges and independent transformers. The converter is bidirectional, fully modular, and scalable. It allows the connection of multiple power sources and loads that may change its power flow direction, allowing hot connection and disconnection of modules. The control of the power flow in each port depends on the relative phase shift among the control pulses of the other active bridges. An iterative algorithm is developed and implemented in a digital device to control the converter in real time. Besides theoretical analysis, the main characteristics of the converter have been validated in a lab prototype with five modules. The experimental results validate the theoretical predictions. Power distribution among the modules has been kept under 9% of error with respect to the desired value, considering an open-loop control.