Novel reference current generation technique for shunt active power filter under unbalanced and distorted grid

Abstract

The prevalence of nonlinear loads has increased significantly due to technological advancements. As a consequence, harmonics are introduced into the current supplied by the grid. This leads to distortion in the voltage at the point of common coupling (PCC), an increase in transmission line losses, and a deterioration of the power factor. To address these issues, a Shunt Active Power Filter (SAPF) is integrated into the power system at the PCC to supply the harmonic, reactive, and neutral currents required by the load. This paper introduces a novel method that utilizes a Linear Kalman Filter (LKF) to generate a reference current for the SAPF, even in the presence of an unbalanced and distorted voltage at PCC. To keep the DC-link capacitor voltage constant, Proportional and Integral (PI) control is used. Notably, this method eliminates the need for a Phase-Locked Loop (PLL), reducing the computational burden on the controller. The proposed approach is robust and exhibits a favorable dynamic response. The MATLAB/Simulink environment is employed to verify the outcomes of the proposed control technique across various voltage and load scenarios.