Fuzzy Adaptive Time-Delay Feedback Controlling Chaos in Buck Converter

摘要

In order to control the chaotic phenomenon of the buck converter, a nonlinear model based on differential equation is established for the buck converter in this paper. The system phase portrait and bifurcation diagram are analyzed based on the output voltage and input current, then the fuzzy adaptive time-delay feedback control (TDFC) strategy is proposed to control the buck converter. The strategy is designed for the purpose of calculating the delay time and the range of feedback gain based on quantitative analysis in the frequency domain via the harmonic balance method. By adaptively adjusting the parameters of the time delay and feedback gain based on fuzzy adaptive algorithm, the buck converter can work in the period-1 orbit to ensure an ideal output quality. Moreover, better robustness and smaller voltage ripple for the buck converter are also achieved compared to traditional TDFC control methods. Numerical simulation results are provided to show the good performance of the proposed strategy.