Robust frequency-estimation method for distorted and imbalanced three-phase systems using discrete filters

The continuous monitoring of voltage characteristics in electric power systems, such as in microgrids, is required for power quality assessment, grid control, and protection purposes. Due to the presence of disturbances in the grid voltage, such as harmonics, imbalances, noise, and offsets introduce...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on power electronics 2011-04, Vol.26 (4), p.1089-1101
Main Authors: Roncero-Sanchez, Pedro, del Toro Garcia, Xavier, Torres, Alfonso Parreno, Feliu, Vicente
Format: Article
Language:English
Subjects:
Accuracy
Algorithms
Discrete-time filters
distributed generation (DG)
Disturbances
Electric potential
Electric power
Electric power generation
Electric power systems
Electrical equipment
Electronics
Estimating techniques
Filtering
Frequency control
Frequency estimation
harmonics
microgrid
monitoring
Power quality
Robust control
Robustness
Simulation
Voltage
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The continuous monitoring of voltage characteristics in electric power systems, such as in microgrids, is required for power quality assessment, grid control, and protection purposes. Due to the presence of disturbances in the grid voltage, such as harmonics, imbalances, noise, and offsets introduced by the instrumentation, among others, the frequency-estimation process has to be robust against all these disturbances to obtain an accurate estimation of the frequency value. This paper presents a fast and accurate method to estimate the fundamental frequency of an electric power system. The estimation method works properly in balanced and imbalanced three-phase systems, and even in single-phase systems. The proposed solution is based on an algebraic method, which is able to calculate the frequency of a pure sinusoidal signal using three samples. A filtering stage is used to increase the robustness of the algorithm against disturbances in a wide frequency range. Simulation and experimental results show the good performance of the method for single- and three-phase systems with a high level of harmonic distortion, even in the presence of amplitude, phase, and frequency changes.
ISSN:0885-8993
1941-0107
DOI:10.1109/TPEL.2011.2107580