Improvement of Phasor Measurement Unit Performance

Abstract

Fast measurements of the instantaneous amplitude and phase angle of the fundamental components and frequency in three-phase power systems may be investigated with high accuracy through the use of modern power instruments such as Phasor Measurement Unit (PMU). However, this accuracy may be affected by several encountering power disturbances, such as abrupt frequency deviation, fast and slow dc offsets decaying due to sudden current changes, inter-harmonics, etc. To avoid these effects for improving the quality of measurements, this work presents a new method of real-time filtering for removing the unwanted DC offset and hence improving SDFT algorithm. To validate the proposed method, the performances of PMU are tested using the data generated by Simulink/MATLAB simulator. The obtained results are very encouraging