In recent years, the stacked polyphase bridges converter has gained increasing interest due to its modularity and scalability for different power and voltage levels. To maintain the advantages from this architecture, distributed control system is required instead of centralized control system. A serial communication protocol based distributed control architecture for an SPB converter consisting of four submodules is presented and experimentally verified in this paper. Moreover, the sensitiveness of the distributed control system to modulation effect, communication delay, and communication speed is also investigated.