Efficient Control Scheme for Five-level (NPC) Shunt Active Power Filters Based on Fuzzy Control Approaches

Abstract

This paper present simple fuzzy control approaches for shunt active power filter based on five-level (NPC) inverter which can mitigate current harmonics generated by nonlinear loads and compensate reactive power. Today, five-level inverter is strongly used in the medium and high voltage applications; these advantages are low harmonic distortions, low switching losses, low electromagnetic interference and low acoustic noise. Second, fuzzy logic techniques have been successfully employed in several power electronic applications. To benefit from these advantages a novel control scheme based on fuzzy current controller is adopted; it is designed to improve compensation capability by adjusting the current error using a fuzzy rule. The reference current signals required to compensate harmonic currents use the synchronous current detection method, this technique is easy to implement and achieves good results. To maintain the dc voltage across capacitor constant and reduce inverter losses, a proportional integral voltage controller is used. The simulation of global system control and power circuits is performed using Matlab-Simulink and SimPowerSystem toolbox. The results obtained in transient and steady states under various operating conditions show the effectiveness of the proposed shunt active filter based on five-level (NPC) inverter using fuzzy control.