Shunt Active Power Filter Based on Savitzky-Golay Filter: Pragmatic Modelling and Performance Validation

This article introduces a novel reference current generation technique based on the Savitzky–Golay filter (SGF) for shunt active power filter (SAPF). Although the existing and conventional SAPF can mitigate harmonics under grid disturbances and nonlinear load environments, they have numerous performance deficiencies including computational complexity, average filtration ability, and slow dynamic response. The proposed SAPF based on SGF can generate a harmonic-free fundamental reference current that can eventually improve the overall harmonic profile and performance compared to existing SAPFs. In addition, an SGF-based phase-locked loop (PLL) is introduced to generate reference phases directly from the distorted grid voltages by retaining the fundamental information of the signal. Thus, it does not induce any phase delay or distortions in the output, unlike the conventional PLLs utilized in the SAPFs. Comparative analysis of performance evaluation is carried out with other SAPFs, and the findings represent the principal achievements of this article. This includes a substantial improvement in performance and harmonic profile under transient conditions. The results are further validated through simulation analysis and hardware implementation.