Analysis of the dc-link stability for the stacked polyphase bridges converter

This paper presents an analysis of the capacitor voltage stability for a stacked polyphase bridges (SPB) type converter. The SPB converter comprises of several submodules which are connected in series. Therefore, stability of the dc-link voltage is very important to investigate. From the analysis, a corresponding controller and an analytical expression for stability are derived. The proposed controller and the associated stability condition are verified in a simulation environment and on a small experimental setup.