Bumpless transfer of non-inverting buck boost converter among multiple working modes

In dealing with the wide operation voltage of renewable energy and energy storage devices, Non-inverting buck-boost converter (NIBB) has been utilized for DC-DC power conversion. This converter shows high efficiency with multi-mode operation. However, transition among multiple working modes will inevitably introduce the “voltage bump”, thus hindering the performance of power converter. In this paper, the cause of voltage bump is first revealed. In elimination of the voltage bump, an improved buck/boost mode is introduced as transition mode, and current feed-forward compensation has been proposed. The combined method is evaluated against classical solutions and verified through the gradual improvement of control performance.