The conventional passive LRC filter has been used widely due to its simple and reliable features in the aspects of suppressing the output voltage dv/dt and harmonic component of the power electronic converter. Since the inductance of conventional LRC output filter is in general of single-pole distribution and the filtering characteristic of the output positive and negative pole of converter is asymmetrical

which lead to distortion in the output voltage. To this issue

in this paper

the distorted output voltage of a conventional filter is analyzed and a kind of improved LRC filter is proposed. The symmetry of filtering characteristic is achieved by way of even sharing positive and negative pole of filtering inductance

which eliminates effectively the output voltage distortion of conventional LRC filter. And the efficiency of the improved filter is verified by the simulation.