Boundary Conditions of Subharmonic Oscillations in Fixed-Switching-Frequency DC-DC Converters
Advanced Analog Technology（先进模拟科技公司）
Chung-Chieh Fang
备注：
Title changed. Submitted to a journal on 2/24/11, and resubmitted to IJCTA on 8/10/11. Added: S-plot to determine the required ramp slope, V2 control, a counterexample (Example 5) of the ripple index hypothesis. The key results traced back from my 1997 PhD thesis, available: http://www.lib.umd.edu/drum/. My five IJCTA papers in arXiv have two common reviewers
发表信息：
Nonlinear Dynamics, 77(1-2), pp. 185-208, Jul. 2014
Design-oriented boundary conditions for subharmonic oscillations are of great interest recently. Based on a subharmonic oscillation boundary condition reported in a PhD thesis more than a decade ago, extended new boundary conditions are derived in closed forms for general switching DC-DC converters. Sampled-data and harmonic balance analyses are applied and generate equivalent results. It is shown that equivalent series resistance causes the boundary conditions for voltage/current mode control to have similar forms. Some recently reported boundary conditions become special cases in view of the general boundary conditions derived. New Nyquist-like design-oriented plots are proposed to predict or prevent the occurrence of the subharmonic oscillation. The relation between the crossover frequency and the subharmonic oscillation is also analyzed.
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