A DC noise error compensator of single-phase grid-connected converter in D-Q synchronous reference frame

This paper proposes a dc error compensation algorithm using d-q synchronous coordinate transform phase-locked-loop in single-phase grid-connected converters. The DC errors are caused by the process of analog to digital conversion and the distorted grid voltage. The DC error can be remove by controlled the synchronous d-axis voltage using integral operation and digital infinite impulse response filter. In this paper, integral compensator and digital infinite impulse response filter are applied in order to remove the DC errors which cause the periodic ripples with grid frequency in D-Q synchronous coordinate transform phase-locked-loop.