【摘要】 混沌扩频技术应用于高频开关电源,能把集中在开关频率及其谐波上的电磁干扰(EMI)扩散在连续的频谱上,有效改善开关电源的电磁兼容(EMC)特性。但研究表明,采用混沌扩频技术后,会对高频开关电源输出电压的纹波产生影响。从理论上对这一现象进行分析,利用输出电压的功率谱密度函数和转移函数,提出了开关电源输出电压纹波随混沌调制系数变化的计算方法。理论分析表明,高频开关电源输出电压的纹波会随混沌调制系数的增大而有所增加,从理论上验证了已有的研究成果。提出了抑制混沌开关电源输出电压纹波的方法,可使输出电压的纹波降低到未采用混沌扩频技术前的水准。更多还原

【Abstract】 Chaotic spectrum-spread technology is used in high frequency power converter to disperse the EMI(ElectroMagnetic Interference),which is concentrated on the switching frequency and its harmonics,over the continuous spectrum to improve its EMC(ElectroMagnetic Compatibility). Research shows that,the chaotic spectrum-spread technology affects the output voltage ripple of power converter.Theoretical analysis is carried out and the method of calculating the output voltage ripple according to chaotic modulation coefficient by using the PSD function and transfer function of output voltage is presented.Theoretical research shows that,the output voltage ripple increases with the increase of chaotic modulation coefficient,which is in accordance with the known experimental results.Two methods for suppressing output voltage ripple caused by chaotic spectrum-spread technology are given.更多还原