Adaptive Phasor Estimation for Smart Electric Grid Monitoring Applications

Abstract

The smart electric grid with enhanced renewable energy (RE) integration is facing the inherent RE uncertainty and intermittency. As one of the widely deployed intelligence electronic devices in the power grid, the Phasor Measurement Units (PMUs) support the requirements of closely monitoring dynamic signals and possibly help with automated control. However, Discrete Fourier Transform (DFT) for estimating phasor for a common fundamental frequency (50/60 Hz) in PMUs is not applicable for capturing dynamic disturbance under non-nominal frequency conditions of the smart grids. The operating conditions of the smart grid are more dynamic than the traditional power grid, and the attenuated phasors can also be produced if it operates at an undesired frequency during oscillations or dynamic events. This paper presents a novel adaptive phasor estimation algorithm based on Wavelet Transform (WT), which utilizes Energy Theory to dynamically switch between the best options to enhance the performance of PMU based applications. The proposed method is validated and tested using Simulink model, and the results indicates that the proposed method has high accuracy and robustness in phasor estimation and industrial applications.