A Single-Switch Quadratic Boost DC-DC Converter With Inherent Clamped Circuit

This paper proposes a quadratic boost DC-DC converter with an inductor at the input to ensure uninterrupted input current and a combination of switched capacitor (SC) cells and coupled inductor (CL) to greatly enhance the boost capability, while one of the SC cells is used as a clamped circuit to mitigate the leakage inductance-induced voltage spikes. In contrast to a direct connection to the output ground, the output capacitor is linked to the SC of the SC cell in order to reduce the capacitor voltage stress. The proposed converter employs a single switch, low input current ripple, and common ground, thereby achieving an ultra-high voltage gain that is higher than that of the existing proposals with a duty cycle less than 0.5. It also features an inherent clamped circuit and a small passive component volume. For illustration purposes, the operating mode, steady-state parameters, small-signal mode, and comparison studies are provided. A 150-W prototype was constructed to validate the analysis, comprising a 30-V input and 600-V output voltage. The prototype demonstrated voltage gains of 20 and 14.2 times with efficiencies of 92.7% and 94.2%, respectively, under full-load conditions.