Enhanced IpD2FT-based Synchrophasor Estimation through Narrowband Interferers Compensation

Smart grid monitoring requires increasingly accurate and fast Phasor Measurement Units (PMUs). Usually, the most challenging testing conditions are those involving low-order harmonics and out-of-band inter-harmonics. This paper presents an algorithm that strongly mitigates the detrimental effects of such disturbances over two-cycle-long observation intervals. Firstly, the frequency values of both the fundamental and the narrowband components safely exceeding the noise floor are computed through the estimation of signal parameters via the rotational invariance technique (ESPRIT), which is particularly effective over short observation intervals. Then, the vectors of spectral samples are processed by the Dynamic Discrete Fourier Transform (IpD2FT) algorithm whose arrays are augmented by including the terms related to the detected narrowband components. The results obtained in the most critical steady-state testing conditions defined in the IEEE/IEC 60255-118-1:2018 Standard are better than those achieved with the original IpD2FT algorithm.