Study of Fractional Order PI DC-DC Converter Based on Dual Closed-loop Control

Abstract

In this paper, the dual closed-loop control strategy with fractional-order PI is applied to the field of the DC-DC converter, which effectively improves the dynamic performance and static performance of the output voltage of the power electronic DC chopper converter. The open-loop transfer function of the Boost converter is obtained by modeling and analyzing the operating principle and small-signal model of the Boost converter, and the fractional-order PI parameters of the double closed-loop control are obtained by combining the frequency-domain analysis design method of control theory. The Simulink simulation model is built, and the fractional-order PI control model is compared and analyzed with the single-voltage loop control and the integer-order PI control model. The results show that the fractional-order PI-controlled Boost converter has a faster response and stronger anti-interference capability, which effectively improves the dynamic performance and static performance index of the DC-DC converter and provides a theoretical basis for the research of dual closed-loop control strategy of the DC-DC converter.