Fundamental frequency sequence amplitude estimator for power and energy applications

A grid-synchronization-based fundamental frequency positive-sequence (FFPS) and negative-sequence (FFNS) amplitudes estimation technique is proposed for unbalanced and distorted grid. In this technique, the sequence amplitudes are extracted by extracting the phase-angle of the FFPS and FFNS components. The extracted phase-angles have DC and double frequency AC components. The AC component is filtered out by using a Moving Average Filter (MAF) of appropriate window length. From the extracted phase-angle, the unknown frequency can be estimated by using a suitable controller. A frequency-fixed equidistant samples-based pre-loop filter is also applied to eliminate the effect of measurement offset. The proposed technique has a very simple structure and is easy to tune. Small-signal modeling-based stability analysis and gain tuning procedure are also provided. The proposed technique strikes a good balance between fast convergence and disturbance rejection capability. Comparative numerical simulation and experimental results with similar other techniques demonstrate the suitability and performance enhancement by the proposed technique.

• fundamental frequency estimation
• grid synchronization
• unbalanced grid conditions
• distorted grids
• moving average filter
• frequency estimation
• small-signal stability
• controller gain tuning
• power quality
• energy applications

• 7 — Énergie propre et d’un coût abordable

• Power Quality and Harmonics
• Microgrid Control and Optimization
• Advanced Electrical Measurement Techniques
• fundamental frequency estimation
• grid synchronization
• unbalanced grid conditions
• distorted grids
• moving average filter
• frequency estimation
• small-signal stability
• controller gain tuning
• Electrical and Electronic Engineering
• Control and Systems Engineering
• Engineering