一种谐波电流超标问题的分析与解决

Analysis and solution of harmonic current over-criterion phenomenon

带有桥式整流滤波电路的设备在电磁兼容性试验中普遍存在谐波电流检测超标现象,通过对这些超标现象进行分析,找出其谐波电流产生的原因,提出无源功率因数校正和有源功率因数校正两种解决方案,并对两种方法的优缺点进行了分析。通过实验证明,采用无源功率因数校正法,谐波电流整体下降了约10dB,采用有源功率功率因数校正法,谐波电流整体下降了约20dB,两种方法都能使原超标设备满足标准要求,验证了上述两种方法的有效性。

In electromagnetic compatibility experiments,harmonic current over-criterion phenomenon often exists in the equipments with bridge rectifier filtering circuit.The causes of harmonic current were found out by analyzing this over-criterion phenomenon.Two solutions which are passive power factor correction and active power factor correction are proposed.The advantages and disadvantages of the two methods are analyzed.The experiments proves that the passive power factor correction method can reduce the harmonic current of about 10 dB,and the active power factor correction method can reduce the harmonic current of about 20dB.The two methods can make the original over-criterion equipment to meet the standard requirements.The availability of the two methods was verified.