Dynamic Behavior Analysis of Nonideal Single‐Inductor Dual‐Output Buck Converter With Voltage Mode Control

ABSTRACT Single‐inductor multi‐output dc–dc converters have been widely used in the field of power energy due to their advantages of small size, multiple outputs, and low cost. However, the parasitic parameters of components lead to complex dynamic behaviors, which seriously impact the stability of the converter. In this paper, the dynamic behavior of a nonideal SIDO buck converter with voltage control is analyzed. A discrete iterative mapping model of the nonideal SIDO buck converter is established. Based on the bifurcation diagram of output voltage and the eigenvalues of the model Jacobian matrix, the impact of control parameters on the stability of ideal and nonideal systems is analyzed, and the impact of parasitic parameters on the stability of the nonideal system is discussed. The theoretical analysis results show that the stability domain between ideal and nonideal SIDO buck converters exhibits significant differences when the control parameters change. The decrease in a parasitic resistor of circuit components or increase in the forward voltage of the freewheeling diode will cause Hopf bifurcation in the nonideal SIDO buck converter. Finally, the simulation results and experimental results verify the correctness of the theoretical analysis.