中国物理B ›› 2017, Vol. 26 ›› Issue (11): 118401-118401.doi: 10.1088/1674-1056/26/11/118401

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Sampled-data modeling and dynamical effect of output-capacitor time-constant for valley voltage-mode controlled ewline buck-boost converter

Shu-Han Zhou(周述晗), Guo-Hua Zhou(周国华), Shao-Huan Zeng(曾绍桓), Min-Rui Leng(冷敏瑞), Shun-Gang Xu(徐顺刚)   

  1. Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle of Ministry of Education, School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031, China
  • 收稿日期:2017-04-30 修回日期:2017-07-24 出版日期:2017-11-05 发布日期:2017-11-05
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61371033 and 51407054), the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 201442), and the Fundamental Research Funds for the Central Universities of China (Grant No. 2682016CX035).

Sampled-data modeling and dynamical effect of output-capacitor time-constant for valley voltage-mode controlled ewline buck-boost converter

Shu-Han Zhou(周述晗), Guo-Hua Zhou(周国华), Shao-Huan Zeng(曾绍桓), Min-Rui Leng(冷敏瑞), Shun-Gang Xu(徐顺刚)   

  1. Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle of Ministry of Education, School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031, China
  • Received:2017-04-30 Revised:2017-07-24 Online:2017-11-05 Published:2017-11-05
  • Contact: Guo-Hua Zhou E-mail:ghzhou-swjtu@163.com
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61371033 and 51407054), the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 201442), and the Fundamental Research Funds for the Central Universities of China (Grant No. 2682016CX035).

摘要:

By analyzing the output voltage ripple of a buck-boost converter with large equivalent series resistance (ESR) of output capacitor, one valley voltage-mode controller for buck-boost converter is proposed. Considering the fact that the increasing and decreasing slopes of the inductor current are assumed to be constant during each switching cycle, an especial sampled-data model of valley voltage-mode controlled buck-boost converter is established. Based on this model, the dynamical effect of an output-capacitor time-constant on the valley voltage-mode controlled buck-boost converter is revealed and analyzed via the bifurcation diagrams, the movements of eigenvalues, the Lyapunov exponent spectra, the boundary equations, and the operating-state regions. It is found that with gradual reduction of output-capacitor time-constant, the buck-boost converter in continuous conduction mode (CCM) shows the evolutive dynamic behavior from period-1 to period-2, period-4, period-8, chaos, and invalid state. The stability boundary and the invalidated boundary are derived theoretically by stability analysis, where the stable state of valley voltage-mode controlled buck-boost converter can enter into an unstable state, and the converter can shift from the operation region to a forbidden region. These results verified by time-domain waveforms and phase portraits of both simulation and experiment indicate that the sampled-data model is correct and the time constant of the output capacitor is a critical factor for valley voltage-mode controlled buck-boost converter, which has a significant effect on the dynamics as well as control stability.

关键词: buck-boost converter, valley voltage-mode control, sampled-data modeling, dynamics

Abstract:

By analyzing the output voltage ripple of a buck-boost converter with large equivalent series resistance (ESR) of output capacitor, one valley voltage-mode controller for buck-boost converter is proposed. Considering the fact that the increasing and decreasing slopes of the inductor current are assumed to be constant during each switching cycle, an especial sampled-data model of valley voltage-mode controlled buck-boost converter is established. Based on this model, the dynamical effect of an output-capacitor time-constant on the valley voltage-mode controlled buck-boost converter is revealed and analyzed via the bifurcation diagrams, the movements of eigenvalues, the Lyapunov exponent spectra, the boundary equations, and the operating-state regions. It is found that with gradual reduction of output-capacitor time-constant, the buck-boost converter in continuous conduction mode (CCM) shows the evolutive dynamic behavior from period-1 to period-2, period-4, period-8, chaos, and invalid state. The stability boundary and the invalidated boundary are derived theoretically by stability analysis, where the stable state of valley voltage-mode controlled buck-boost converter can enter into an unstable state, and the converter can shift from the operation region to a forbidden region. These results verified by time-domain waveforms and phase portraits of both simulation and experiment indicate that the sampled-data model is correct and the time constant of the output capacitor is a critical factor for valley voltage-mode controlled buck-boost converter, which has a significant effect on the dynamics as well as control stability.

Key words: buck-boost converter, valley voltage-mode control, sampled-data modeling, dynamics

中图分类号:  (Nonlinear dynamics and chaos)

  • 05.45.-a
84.30.Jc (Power electronics; power supply circuits)