Closed-Form Critical Conditions of Subharmonic Oscillations for Buck Converters
Closed-Form Critical Conditions of Subharmonic Oscillations for Buck Converters
复制标题
降压转换器分谐波振荡的闭式临界条件
DOI：
10.1109/tcsi.2012.2230498
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
C. Fang
中科院分区：
文献类型：
--
作者：
C. Fang
在给出了与回路增益有关的次谐波振荡的一般临界条件的基础上，导出了与变换器参数有关的各种控制方案的许多闭式临界条件。一些已知的临界条件在广义框架中成为特殊情况。对于任意控制方案，提出了一个系统的程序来推导该控制方案的临界条件。不同的控制方案具有相似的临界条件形式。例如，V2控制和比例电压模式控制具有相同形式的临界条件。推导出的临界条件可以解释平均电流模式控制中在极窗值处发生次谐波振荡的特殊现象。过去的研究中提出的预测次谐波振荡的纹波幅度指数的应用有限，并且对于与开关频率相当的大极的变换器是无效的。
Based on a general critical condition of subharmonic oscillation in terms of the loop gain, many closed-form critical conditions for various control schemes in terms of converter parameters are derived. Some previously known critical conditions become special cases in the generalized framework. Given an arbitrary control scheme, a systematic procedure is proposed to derive the critical condition for that control scheme. Different control schemes share similar forms of critical conditions. For example, both V2 control and proportional voltage mode control have the same form of critical condition. A peculiar phenomenon in average current mode control where subharmonic oscillation occurs in a window value of pole can be explained by the derived critical condition. A ripple amplitude index to predict subharmonic oscillation proposed in the past research has limited application and is shown invalid for a converter with a large pole comparable to the switching frequency.