Evaluation of windowed ESPRIT virtual instrument for estimating Power Quality Indices

The use of subspace and Matrix Algebra (MA) methods for estimating Power Quality Indices (PQIs) as defined by IEEE Std 1459-2010 is relatively new. For this reason there is room for further research about these methods and their efficiency applied to estimating PQIs. This document presents the design of a Virtual Instrument (VI) based on modern subspace, MA and Least Square (LS) techniques with a Kalman Filter (KF) for estimating PQIs. Further we claim that the efficiency of the subspace method is comparable to the Fourier based methods in typical power system analysis. Simulation and experiments are conducted to further compare the performance of this VI with other VI's which do not use the KF. We also compare this VI with VI's that use the classical Fast Fourier Transform (FFT) based method of estimation.

► Designed two virtual instruments for measuring Power Quality Indices. ► The virtual instruments use subspace, matrix algebra and Kalman filtering. ► Power Quality Indices estimated are as given in IEEE Std 1459-2010. ► Real time measurements show accurate estimates for Power Quality Indices. ► Compared the new instruments with instruments based on the Welch technique.