Diagnosis and compensation of line Current Measurements for Grid Side Converter in PV Application

This paper proposes a fast and easy fault detection and isolation (FDI) technique for line currents measurement of Grid side converter used in PV system. The considered measurement error is offset and scaling errors. Their consequences cause undesirable periodic undulations and DC components, which lead to system performance degradation. The proposed compensation method based on analytical analysis of line currents in (d,q) synchronous reference frame. It is investigated to compute the average value of the undesired periodic undulations in grid frequency (ω)) and (2ω
_g
) through a simple band-pass filter. This method does not need an additional hardware. Simulation results are presented to demonstrate the effectiveness of the proposed FDI and error compensation algorithm.