Hybrid damping for active front end converter

Breakthroughs in power electronics devices enabled the utilization of the IGBT as the main power switch in AFE converters and enabled the emergence of the fully controlled Active Front End, “AFE”, and low input harmonic solution. This solution employs voltage and current control loops and switching with relatively high switching frequencies of greater than 2 KHz in most applications. The AFE converter is usually connected to the grid through an LCL filter. In this paper, a hybrid technique is introduced to damp the resonance condition that may result due to the existence of the LCL filter. This technique relies on the concept of hybrid damping which combines the advantages of both active and passive damping previously introduced in literature. It will also be shown that the introduced technique overcomes previous limitations which renders this technique more practical and highly applicable to reliable industrial products.