Distributed generation (DG) units alter the power flow in distribution networks, which results in changing line losses. When converter-connected DG units are used, not only the fundamental losses will alter, but also the harmonic losses, caused by the effect of the applied converters on the power quality. When damping converters, which are designed to improve the power quality, are used, the harmonic losses are diminished. This paper deals with the influence of damping converter-connected DG units on the harmonic line losses and makes a comparison between the commonly used converters and the damping converter.