开关变换器电磁干扰的混沌抑制技术研究

摘要

针对工作在高频状态下的开关变换器产生的瞬态脉冲含有高频谐波从而形成电磁干扰,电磁干扰通过传导和辐射的途径传播,不但对电网造成污染,而且直接影响到周围其他用电电器的正常工作这一现象.提出了开关变换器电磁干扰EMI的混沌抑制技术的分析和研究,主要以DC-DC Boost变换器为研究对象,介绍了Boost变换器的电路结构及工作原理,建立了状态方程,进行Pspice模拟仿真.证明从Boost变换器中固有的混沌现象出发,在不附加任何外围电路的情况下,通过变换参考电流的方法来使开关变换器的输入电流由普通周期状态变为混沌状态,使周期信号能量集中的频率谱线变为连续平滑频谱,降低高幅值的谱线,从而降低开关变换器的电磁干扰水平.%To solve this problem that switching converter is working in a high frequency state, which can produce a transient pulse containing high frequency harmonics that can emit electromagnetic interference, while electromagnetic interference can cause pollution to the network and direct impact to other electrical appliances to work by conduction and radiation, this paper puts forward analysis and research on Chaos Suppression of EMI in switching converters. Taking boost converter for the study and introduced the circuit structure and the principle of work, established the equation of state, carried on the Pspice simulation, it is proofed that start from boost converter inherent chaos phenomena, no additional any peripheral circuit. Through the method of transform reference current to make the input current of the switch converter from cycle state into chaos state,and make the frequency spectrum of periodic signal energy concentrated into continuous smooth spectrum, and lower high amplitude spectrum line, so that reducing switch converter electromagnetic interference level.