Interphase L-C Resonance and Stability Analysis of Series-Capacitor Buck Converters

Ping Wang, Daniel Zhou, Haoran Li, David M. Giuliano, Gregory Szczeszynski, Stephen Allen, Minjie Chen

Research output: Contribution to journalArticlepeer-review


Hybrid switched capacitor power converters, such as the series-capacitor buck (SCB) converter, have intrinsic L-C resonant dynamics that might influence its control stability and transient response. This letter presents a systematic approach to analyzing this intrinsic resonant behavior, which can be classified into output <inline-formula><tex-math notation="LaTeX">$L$</tex-math></inline-formula>-<inline-formula><tex-math notation="LaTeX">$C_{o}$</tex-math></inline-formula> resonance and interphase <inline-formula><tex-math notation="LaTeX">$L$</tex-math></inline-formula>-<inline-formula><tex-math notation="LaTeX">$C_{B}$</tex-math></inline-formula> resonance based on common-mode and differential-mode decomposition. The impacts of coupled inductors on the resonant amplitude, frequency, and settling time during a step line transient are analyzed. The influence of intrinsic resonance on control stability is clarified, providing guidance for controller design. A two-phase SCB prototype was built and tested with discrete and coupled inductors under different operating conditions. All analysis is verified by simulation or experimental results.

Original languageEnglish (US)
Pages (from-to)1-7
Number of pages7
JournalIEEE Transactions on Power Electronics
StateAccepted/In press - 2023

All Science Journal Classification (ASJC) codes

  • Electrical and Electronic Engineering


  • averaged model
  • Capacitors
  • control
  • coupled inductor
  • Inductors
  • Integrated circuit modeling
  • L-C resonance
  • multiphase converter
  • Perturbation methods
  • series-capacitor buck
  • Transfer functions
  • Transient analysis
  • Voltage

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