PMSG based Standalone Wind Energy Conversion System with Power Quality Enhancement

paper discusses a novel power quality improvement method for standalone permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS). The standalone systems are more susceptible to variations in parameters like voltage, frequency, harmonics, etc. These power quality issues can be addressed using an active power filter (APF) integrated at the point of common coupling (PCC). The traditional APF employs Phase-locked loop (PLL), which estimates the angular frequency, and provides limited performance under these variations. The paper proposes a new technique of reference current generation for active power filter (APF) based on the implementation of self-tuning filter (STF). The inclusion of STF instead of conventional low power filter LPF and high-power filter HPF allows direct extraction of the fundamental component in the & alpha;-& beta; axis from a distorted electrical signal. This approach achieves simplicity and improved robustness by dispensing with the need for a Phase-locked loop (PLL) in the system. An adaptive hysteresis band current controller (AHBCC) is implemented to generate the switching pattern for regulating the APF by modulating the hysteresis band with system parameters thus maintaining the modulation frequency nearly constant. Mathematical analysis along with MATLAB based simulation results verifies the effectiveness of the proposed topology.