A Comparative Analysis of L and LCL Filters in Grid-Connected Converters Regarding Volume and Losses

This study compares the volume and losses of L and LCL filters in grid-connected converters. Optimized filter designs are analyzed for different switching frequency (15 kHz to 100 kHz) and power ratings (500 W to 10 kW). The objective is to identify the points where each filter topology is the best in terms of volume and losses. While the prevailing literature commonly suggests that the LCL filter is expected to outperform the L filter, particularly in terms of volume, the findings of the present study challenge this notion. This was possible because of the consideration of the technological limitations of the materials used in the construction of the inductors. It is shown that for some switching frequencies and power levels, the L filter presents better performance than the LCL filter, both in terms of volume and losses.