Bifurcation analysis of cascaded H-bridge converter controlled by proportional resonant. (February 2021)

• Record Type: Journal Article
• Authors: Yu, Yongjin; Zhang, Chao
• Is Part Of: International journal of electrical power & energy systems. Volume 125(2021)
• Publication Date: 2021-02
• Subjects: Cascaded H-bridge converter -- Bifurcation analysis -- Chaos -- Proportional resonant; Electrical engineering -- Periodicals; Electric power systems -- Periodicals; Électrotechnique -- Périodiques; Réseaux électriques (Énergie) -- Périodiques; Electric power systems; Electrical engineering; Periodicals; 621.3
• DOI: 10.1016/j.ijepes.2020.106476
• Languages: English
• ISSNs: 0142-0615

Abstract

Highlights: A new stroboscopic mapping model is proposed to study the chaos and bifurcation phenomena of PWM converter. A time delay loop is added on the PR control, which effectively suppresses the chaos and bifurcation in the current loop after increasing the proportional gain. A new controller is proposed for the suppression of chaos and bifurcation. Abstract: This paper is concerned with the nonlinear dynamics of Cascaded H-Bridge Converter under PR (Proportional Resonant) control. First, a stroboscopic mapping model of PWM (Pulse Width Modulation) converter is established and the corresponding dynamics, including bifurcations and chaos is investigated analytically. Taking the switching frequency, controller parameters as the bifurcation parameter, some different dynamic behaviors are identified over a wide range of some specified parameter. Moreover, the bifurcation condition is further verified based on the root locus diagram and Lyapunov exponential spectrum. Second, aiming at deriving the stability regions of PWM converter, the variable substitution approach is utilized to transform the non-autonomous converter model into an autonomous one. Then, the PR (Proportional Resonant) controller is applied to control the grid-side current, which can suppress the chaos and bifurcation in the current loop by increasing the proportional gain. Finally, the experiment results are presented to illustrate the validity of the control scheme.