An active trap filter for high-power voltage source converters

This paper proposes a power electronic based device to actively trap the switching current ripples for high-power converters. Control principle and system design of the active trap filter are discussed first. Comparisons of the active trap filter with LCL and LLCL filters are then carried out in time-domain simulations and experimental tests. The results demonstrate that the active trap filter not only provides more controllability and flexibility than the passive filters, but also mitigates the adverse effects of parameter shifts on harmonic filtering performance of passive filters.