A Fast Recursive Algorithm For Spectrum Tracking in Power Grid Systems

Area of Science:

• Electrical Engineering
• Power Systems Analysis
• Signal Processing

Background:

• Wide area measurement systems require precise real-time tracking of power system phase, frequency, and Power Factor (PF).
• Non-linear loads in distribution systems introduce harmonics, sub-harmonics, and inter-harmonics, distorting signal estimation and hindering accurate monitoring.
• Existing methods struggle to effectively track dynamic frequency variations in the presence of complex harmonic distortions.

Purpose of the Study:

• To develop a robust approach for identifying and tracking harmonic, sub-harmonic, and inter-harmonic components in power systems.
• To accurately monitor real-time voltage, current, and frequency variations despite signal distortions.
• To assess the impact of these harmonic components on overall power system behavior.

Main Methods:

• A two-stage processing approach is proposed, beginning with a subspace-based estimation method.
• The first stage detects and identifies all harmonic components within the power system signals.
• The second stage employs a low-complexity fast tracking algorithm for real-time frequency variation monitoring.

Main Results:

• The proposed approach successfully detects and identifies harmonic, sub-harmonic, and inter-harmonic components.
• Simulation results demonstrate highly reliable estimation of these components.
• The algorithm provides fast and accurate tracking of frequency variations, even with time-varying signals.

Conclusions:

• The developed two-stage method offers a reliable solution for monitoring power systems with harmonic distortions.
• It enables accurate real-time tracking of phase and frequency, crucial for wide area measurement systems.
• This approach effectively mitigates the impact of time variance and harmonic interference on signal analysis.