开关电源系统中谐波的抑制

Study on the harmonics of switching power supply

为了提高开关电源电能质量和高功率因素,分析了开关电源中整流变换和逆变器两部分,开关电源运行中会产生谐波成分,整流和逆变过程中都含有3次、5次、7次、9次等以上的奇次谐波和偶次谐波,通过测试可知,3次、5次、7次、9次奇次谐波成分最大,其余高次谐波虽然存在但其能量很低,对系统正常工作的干扰不大,在抑制时可以忽略。基于此,设计出一种新型带通无源滤波器,该滤波器能抑制3次以上的谐波,与传统的滤波器相比具有很好的优越性。试验验证可知,该滤波器能改善电压波形,谐波总量低于我国制定的5%标准。

In order to improve power quality and high power factor in switching power supply,This paper analyzed rectifier and inverter transforms two parts in the switching power supply,theoretical analysis,switching power supply running will produce a harmonic component,rectifier and inverter process contains 3,5th,7th,nine more than second-class odd harmonics and even harmonics,the experiment shows that three times,five times,seven times,nine times the maximum odd harmonic components,and the remaining high-order harmonic although there are,but its energy is low,the interference of the system is not working properly,the suppression can be ignored.Based on this,a new design of a passive band-pass filter,which can suppress harmonics more than 3 times,and the conventional filter has a good advantage.In the end of experimental verification shows that the filter can improve the voltage waveform,the total harmonic formulation of 5％ below our standard.