Three-level (NPC) Shunt Active Power Filter Performances based on Fuzzy Controller for Harmonic Currents Compensation under Non-Ideal Voltage Conditions.

This paper presents three-level (NPC) shunt active power filter the performances based on fuzzy control techniques to compensate harmonic currents generated by non-linear loads operating under non ideal voltage conditions. Shunt APF is the best solution to eliminate harmonics drawn from nonlinear load especially for low power system, the most inverter used is the two-level voltage source inverter. Multilevel inverters are being investigated and recently used for APF topologies. Today Three-level inverter is one of the most used converters in the majority of industrial applications, such as machine drives and power active filters. The control strategy used is based on the synchronous reference frame detection method that gives a good performance particularly if the source voltage is unbalanced or distorted. The new control scheme proposed in this work is based on fuzzy techniques and it is designed to improve APF compensation capability by adjusting the current error based on fuzzy rule. To improve the output three-level voltage inverter and avoid an unbalanced AC voltage waveform a neutral-point potential voltage compensator based on proportional controller is used with a proportional integral controller required to maintain dc voltage constant. The results of simulation study obtained using Matlab-Simulink and SimPowerSystem Toolbox are found quite satisfactory to eliminate harmonics and reactive power components from utility current. [ABSTRACT FROM AUTHOR]