The detail specification and relevant solutions as follows:

This solution is applicable in the products that can directly use the high voltage rectifying way to supply the power. Inserting in the rectifier bridge and filter capacitance, this circuit only consists of one low frequency choke.

The working principle is very simple, the inductance of the low-frequency choke and the rectifier capacitance as well as the distributed capacitance of the low-frequency choke consists of one low frequency harmonic current filter.

The circuit parameters is rather small for 50Hz base wave attenuation component, the harmonic component attenuation is very large for more than three times, especially the third time harmonic wave（150Hz）attenuation is very large.

Low frequency harmonic current suppression filter will achieve the harmonic current suppression purpose by inserting the current circuit after or before rectifying power supply.

It can also solve the harmonic current problems of the product with less than 300W. And it doesn’t need any change of the circuit parameters, and neither decreases the other property of the original power supply. Its defect is that it has big volume; the weight is about 100-200 gram.