Time-domain Dynamic-performance-improvement Method for Pulse-width-modulated DC-DC Converters Based on Eigenvalue and Eigenvector Sensitivity

Abstract

For pulse-width modulated (PWM) DC-DC converters, the input voltage fluctuation and load variation in practical applications make it necessary for them to have better dynamic performance to meet the regulation requirements of the system. The dynamic-performance-improvement method for PWM DC-DC converters is mainly based on indirect dynamic performance indices, such as the gain margin and phase margin. However, both settling time and overshoot in the time domain are important in practical engineering. This makes it difficult for designers to obtain a clear understanding of the time-domain dynamic performance that can be achieved with improved control. In this study, a direct analysis of the time-domain dynamic characteristic of PWM DC-DC converters is performed. A dynamic-performance-improvement method based on eigenvalues and eigenvector sensitivity (E ² S-based DPIM) is proposed to directly improve the time-domain dynamic performance index of PWM DC-DC converters. By considering a boost converter with proportional-integral control as an example, an additional virtual inductor current feedback control was designed using the proposed dynamic-performance-improvement method. Simulation and experimental results verify the validity and accuracy of the proposed dynamic-performance-improvement method.