Adaptive control of an active power filter for harmonic suppression and power factor correction

Harmonic suppression and Power Factor Correction with a Voltage Source Converter used as an Active Power Filter is investigated in this paper. The design of an adaptive-based control is considered to improve control performance in the presence of system uncertainty. The proposed adaptive method has a two-loop structure. The adaptive inner loop current control accounts for parametric uncertainty in the current dynamics of the converter. With a novel change of state coordinates, the DC voltage dynamics is linearized. Accordingly, an outer loop Proportional Integral control is designed to regulate the DC voltage. Simulation and experimental results demonstrate the outstanding performance of the proposed multi-loop control method.