电流模式控制开关功率变换器中的呼吸现象

BREATHING IN CURRENT-MODE CONTROLLED SWITCHING CONVERTER

从电路耦合滤波的角度考虑,以Boost变换器为例揭示了在电流模式控制开关变换器中,由于存在耦合电路引起的传导和辐射干扰,使得有可能产生呼吸现象,这在功率变换电路中是一种非正常的工作状态.可以通过建立具有固定初相位的模拟干扰信号,并使其频率与变换器的开关频率相同,以便将呼吸现象(时间分叉)转换为参数分叉,分析结果与数值仿真是完全一致的,并在电路实验中得到了印证.

With the consideration of coupling filter,breathing possibly exists in a current-mode controlled Boost converter due to the conducted or radiated EMI from inner or outer coupling circuits.It exhibits as a time bifurcation undergoing regular period-1,subharmonics and chaos orderly and repeatedly for a long period.The breathing,as an improper operation state,should be avoided in power converters.By constructing an interference signal with the same frequency as the Boost converter and constant initial phase,time bifurcation (breathing) is mapped into parameter bifurcation.In this way,simulation gains the same results as those from experiment and those from analysis as well.