A Low-stress High-gain Interleaved DC-DC Converter with Self-balancing Capacitor Voltage

A low current ripple and low voltage stress interleaved high-gain boost converter is proposed in this paper. The proposed converter has two inductors in parallel at the input side and multiple capacitors in series at the output side, which reduces the ripple of the input current and the voltage stress on the output capacitor. In addition, the capacitor voltage at the output side of the proposed converter can be self-balancing. In this paper, the operating principle of the proposed converter is analyzed for different duty cycles (d> 0.5, d < 0.5), the small-signal model and the average model of the converter are derived, and the transfer function of the proposed converter is further obtained. To ensure the response speed and stability of the converter, the voltage and current double closed-loop control is adopted, with which classical PI regulators are utilized and designed. Finally, based on the theoretical analysis, a prototype with 150W, 30-70V input and 300V output is built, which controlled by a digital signal processor TMS320F28335. The proposed converter can be utilized in wide-scale fields such as electric vehicles, photovoltaic, and DC microgrid fields.