Study on the Dynamical Characteristic for Current-Feedback BUCK Converter

Current-feedback BUCK Converter, namely CCBUCK, which is the dominant component of SMPS system, have rich dynamical characteristic. For revealing internal relation between stability and system circuit parameters, Dynamical Characteristic for Current-feedback BUCK Converter was studied. Two closed loop circuit model based on PI regulator was built. The simulation model for CCBUCK, controlled by peak current or valley value current, was constructed by using the exact state equations of CCBUCK. Through varying parameters nonlinearity characteristic was simulated and analyzed by numerical method. Through the experiments, the result shows CCBUCK is very sensitive to input voltage, while nonlinearity of CCBUCK, controlled by peak current or valley value current, was opposite. The research results could serve guidance for circuit parameters selection in CCBUCK converter application.