Power quality improvement of DSTATCOM using fast hybrid-PLL-based control method for wind energy applications

In self-excited induction generator (SEIG)-based wind energy systems, voltage and frequency fluctuate with variations in wind speed and load, reducing power quality and efficiency. A distribution static synchronous compensator (DSTATCOM) is an effective solution to mitigate these fluctuations but requires real-time and accurate control, including precise estimation of voltage and current parameters. This paper proposes a fast hybrid-phase locked loop (FH-PLL)-based DSTATCOM control algorithm, offering superior filtering capabilities and enhanced sensitivity in detecting amplitude, frequency, and phase angle variations. The proposed method significantly improves the performance of DSTATCOM-assisted SEIG energy systems. Unlike conventional alternatives, which often suffer from either low estimation accuracy or high computational complexity, the proposed approach achieves an optimal balance between computational efficiency and estimation precision, making it a superior alternative to existing control algorithms. Comprehensive comparative performance evaluations under various challenging conditions such as non-linear loads, unbalanced loads, open-circuit faults, and measurement offsets, demonstrate that the proposed method achieves the lowest total harmonic distortion (THD) and total demand distortion (TDD) compared to state-of-the-art techniques, including the enhanced phase locked loop (EPLL), second-order generalized integrator (SOGI), and conventional synchronous reference frame PLL (SRF-PLL), while remaining compliant with the relevant IEEE 519-2014 standards.