Stability-improvement method of cascaded DC-DC converters with additional voltage-error mutual feedback control

Abstract

The interaction between the source and load converters in cascaded DC-DC converters may cause instability. Thus, improving the stability of cascaded DC-DC converters is important. To solve the above-mentioned problem, a flowchart to improve the control method is established by calculating the eigenvalue sensitivity of a time-domain model of cascaded DC-DC converters. Further, an additional voltage-error mutual feedback control method is firstly proposed based on the flowchart provided in this study to improve the stability of cascaded DC-DC converters. Subsequently, the influence of the proposed mutual feedback control on the stability of cascaded DC-DC converters is analyzed. Finally, the effectiveness of the proposed control method is verified by simulation and experiment.