Wavelet-Based Monitor for Grid Impedance Estimation of Three-Phase Networks

This article proposes a wavelet-based monitor (WBM) for grid impedance estimation, which combines transient detection scheme (WB-TDS) and estimator (WB-GIE). The WB-TDS employs the analysis of wavelet coefficients energy detecting changing, whereas WB-GIE estimates by using real-time stationary discrete packet transform associated with signal injection scheme. During triggers injecting an interharmonic into power to estimate its current impedance. method mitigates total harmonic distortion generated continuous employed in existing techniques. identifies phase resistance reactance accurately balanced or unbalanced conditions. Due inherent characteristics, WBM is suitable be inserted adaptive flow control distributed generation systems. Experimental results obtained from grid-connected photovoltaic laboratory setup validates proposed demonstrates effectiveness.